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Implement THIS_MODULE equivalent #15

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Implement THIS_MODULE equivalent #15

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@ojeda ojeda commented Sep 20, 2020

Not sure what is the best/cleanest interface to give users -- currently they need to pass others THIS_MODULE.0, which does not look that good. Perhaps giving them a get_this_module() that returns that is better. Also we could consider having a struct ThisModule. Anyway, this gives us access to the address.

@@ -38,7 +38,7 @@ impl Builder {
self
}

pub fn build(self) -> KernelResult<Registration> {
pub fn build(self, this_module: *mut bindings::module) -> KernelResult<Registration> {
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We need a safer wrapper around this, otherwise passing the raw ptr makes this interface unsafe.

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Passing the address is not unsafe on its own. I agree that it could look better (e.g. a struct ThisModule as I mentioned in the message above).

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Because this will deref the ptr, and creating a raw ptr is safe, the impact is that this is unsound :-)

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Yeah, it is definitely unsound, but the interface isn't unsafe due to the pointer passing on its own -- i.e. if we could check the pointer (somehow), then the function wouldn't need to be unsafe to be sound.

Related: at some point we will have to establish some guidelines in the docs (before Rust code starts growing quickly with people calling kernel APIs directly etc.) on "how much soundness-correct" we want to be (see similar discussions in e.g. cxx).

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Sure, but there's no way to check if the pointer is correct :-)

In general, safe interfaces can't really take raw pointers for this reason.

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I know, that is why I said "somehow" :-)

I think in my first reply you understood I was disagreeing about the function needing to be marked unsafe or having a proper abstraction -- I was only (pedantically) pointing out that it is not the passing but what we do with the pointer that makes the function unsafe.

Signed-off-by: Miguel Ojeda <[email protected]>
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ojeda commented Oct 4, 2020

A quick commit to try the CI

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kloenk commented Oct 10, 2020

This would fix #10, right?

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alex commented Oct 10, 2020

Yup

@alex alex linked an issue Oct 10, 2020 that may be closed by this pull request
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alex commented Oct 11, 2020 via email

ojeda pushed a commit that referenced this pull request Nov 28, 2020
…s metrics" test

Linux 5.9 introduced perf test case "Parse and process metrics" and
on s390 this test case always dumps core:

  [root@t35lp67 perf]# ./perf test -vvvv -F 67
  67: Parse and process metrics                             :
  --- start ---
  metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC
  parsing metric: inst_retired.any / cpu_clk_unhalted.thread
  Segmentation fault (core dumped)
  [root@t35lp67 perf]#

I debugged this core dump and gdb shows this call chain:

  (gdb) where
   #0  0x000003ffabc3192a in __strnlen_c_1 () from /lib64/libc.so.6
   #1  0x000003ffabc293de in strcasestr () from /lib64/libc.so.6
   #2  0x0000000001102ba2 in match_metric(list=0x1e6ea20 "inst_retired.any",
            n=<optimized out>)
       at util/metricgroup.c:368
   #3  find_metric (map=<optimized out>, map=<optimized out>,
           metric=0x1e6ea20 "inst_retired.any")
      at util/metricgroup.c:765
   #4  __resolve_metric (ids=0x0, map=<optimized out>, metric_list=0x0,
           metric_no_group=<optimized out>, m=<optimized out>)
      at util/metricgroup.c:844
   #5  resolve_metric (ids=0x0, map=0x0, metric_list=0x0,
          metric_no_group=<optimized out>)
      at util/metricgroup.c:881
   #6  metricgroup__add_metric (metric=<optimized out>,
        metric_no_group=metric_no_group@entry=false, events=<optimized out>,
        events@entry=0x3ffd84fb878, metric_list=0x0,
        metric_list@entry=0x3ffd84fb868, map=0x0)
      at util/metricgroup.c:943
   #7  0x00000000011034ae in metricgroup__add_metric_list (map=0x13f9828 <map>,
        metric_list=0x3ffd84fb868, events=0x3ffd84fb878,
        metric_no_group=<optimized out>, list=<optimized out>)
      at util/metricgroup.c:988
   #8  parse_groups (perf_evlist=perf_evlist@entry=0x1e70260,
          str=str@entry=0x12f34b2 "IPC", metric_no_group=<optimized out>,
          metric_no_merge=<optimized out>,
          fake_pmu=fake_pmu@entry=0x1462f18 <perf_pmu.fake>,
          metric_events=0x3ffd84fba58, map=0x1)
      at util/metricgroup.c:1040
   #9  0x0000000001103eb2 in metricgroup__parse_groups_test(
  	evlist=evlist@entry=0x1e70260, map=map@entry=0x13f9828 <map>,
  	str=str@entry=0x12f34b2 "IPC",
  	metric_no_group=metric_no_group@entry=false,
  	metric_no_merge=metric_no_merge@entry=false,
  	metric_events=0x3ffd84fba58)
      at util/metricgroup.c:1082
   #10 0x00000000010c84d8 in __compute_metric (ratio2=0x0, name2=0x0,
          ratio1=<synthetic pointer>, name1=0x12f34b2 "IPC",
  	vals=0x3ffd84fbad8, name=0x12f34b2 "IPC")
      at tests/parse-metric.c:159
   #11 compute_metric (ratio=<synthetic pointer>, vals=0x3ffd84fbad8,
  	name=0x12f34b2 "IPC")
      at tests/parse-metric.c:189
   #12 test_ipc () at tests/parse-metric.c:208
.....
..... omitted many more lines

This test case was added with
commit 218ca91 ("perf tests: Add parse metric test for frontend metric").

When I compile with make DEBUG=y it works fine and I do not get a core dump.

It turned out that the above listed function call chain worked on a struct
pmu_event array which requires a trailing element with zeroes which was
missing. The marco map_for_each_event() loops over that array tests for members
metric_expr/metric_name/metric_group being non-NULL. Adding this element fixes
the issue.

Output after:

  [root@t35lp46 perf]# ./perf test 67
  67: Parse and process metrics                             : Ok
  [root@t35lp46 perf]#

Committer notes:

As Ian remarks, this is not s390 specific:

<quote Ian>
  This also shows up with address sanitizer on all architectures
  (perhaps change the patch title) and perhaps add a "Fixes: <commit>"
  tag.

  =================================================================
  ==4718==ERROR: AddressSanitizer: global-buffer-overflow on address
  0x55c93b4d59e8 at pc 0x55c93a1541e2 bp 0x7ffd24327c60 sp
  0x7ffd24327c58
  READ of size 8 at 0x55c93b4d59e8 thread T0
      #0 0x55c93a1541e1 in find_metric tools/perf/util/metricgroup.c:764:2
      #1 0x55c93a153e6c in __resolve_metric tools/perf/util/metricgroup.c:844:9
      #2 0x55c93a152f18 in resolve_metric tools/perf/util/metricgroup.c:881:9
      #3 0x55c93a1528db in metricgroup__add_metric
  tools/perf/util/metricgroup.c:943:9
      #4 0x55c93a151996 in metricgroup__add_metric_list
  tools/perf/util/metricgroup.c:988:9
      #5 0x55c93a1511b9 in parse_groups tools/perf/util/metricgroup.c:1040:8
      #6 0x55c93a1513e1 in metricgroup__parse_groups_test
  tools/perf/util/metricgroup.c:1082:9
      #7 0x55c93a0108ae in __compute_metric tools/perf/tests/parse-metric.c:159:8
      #8 0x55c93a010744 in compute_metric tools/perf/tests/parse-metric.c:189:9
      #9 0x55c93a00f5ee in test_ipc tools/perf/tests/parse-metric.c:208:2
      #10 0x55c93a00f1e8 in test__parse_metric
  tools/perf/tests/parse-metric.c:345:2
      #11 0x55c939fd7202 in run_test tools/perf/tests/builtin-test.c:410:9
      #12 0x55c939fd6736 in test_and_print tools/perf/tests/builtin-test.c:440:9
      #13 0x55c939fd58c3 in __cmd_test tools/perf/tests/builtin-test.c:661:4
      #14 0x55c939fd4e02 in cmd_test tools/perf/tests/builtin-test.c:807:9
      #15 0x55c939e4763d in run_builtin tools/perf/perf.c:313:11
      #16 0x55c939e46475 in handle_internal_command tools/perf/perf.c:365:8
      #17 0x55c939e4737e in run_argv tools/perf/perf.c:409:2
      #18 0x55c939e45f7e in main tools/perf/perf.c:539:3

  0x55c93b4d59e8 is located 0 bytes to the right of global variable
  'pme_test' defined in 'tools/perf/tests/parse-metric.c:17:25'
  (0x55c93b4d54a0) of size 1352
  SUMMARY: AddressSanitizer: global-buffer-overflow
  tools/perf/util/metricgroup.c:764:2 in find_metric
  Shadow bytes around the buggy address:
    0x0ab9a7692ae0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692af0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  =>0x0ab9a7692b30: 00 00 00 00 00 00 00 00 00 00 00 00 00[f9]f9 f9
    0x0ab9a7692b40: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
    0x0ab9a7692b50: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
    0x0ab9a7692b60: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 00 00 00 00
    0x0ab9a7692b70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
  Shadow byte legend (one shadow byte represents 8 application bytes):
    Addressable:           00
    Partially addressable: 01 02 03 04 05 06 07
    Heap left redzone:	   fa
    Freed heap region:	   fd
    Stack left redzone:	   f1
    Stack mid redzone:	   f2
    Stack right redzone:     f3
    Stack after return:	   f5
    Stack use after scope:   f8
    Global redzone:          f9
    Global init order:	   f6
    Poisoned by user:        f7
    Container overflow:	   fc
    Array cookie:            ac
    Intra object redzone:    bb
    ASan internal:           fe
    Left alloca redzone:     ca
    Right alloca redzone:    cb
    Shadow gap:              cc
</quote>

I'm also adding the missing "Fixes" tag and setting just .name to NULL,
as doing it that way is more compact (the compiler will zero out
everything else) and the table iterators look for .name being NULL as
the sentinel marking the end of the table.

Fixes: 0a507af ("perf tests: Add parse metric test for ipc metric")
Signed-off-by: Thomas Richter <[email protected]>
Reviewed-by: Sumanth Korikkar <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
ojeda pushed a commit that referenced this pull request Nov 28, 2020
The evsel->unit borrows a pointer of pmu event or alias instead of
owns a string.  But tool event (duration_time) passes a result of
strdup() caused a leak.

It was found by ASAN during metric test:

  Direct leak of 210 byte(s) in 70 object(s) allocated from:
    #0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
    #1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414
    #2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414
    #3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
    #4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
    #5 0x559fbbcc95da in __parse_events util/parse-events.c:2141
    #6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406
    #7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393
    #8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415
    #9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498
    #10 0x559fbbc0109b in run_test tests/builtin-test.c:410
    #11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
    #12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
    #13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
    #14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: f0fbb11 ("perf stat: Implement duration_time as a proper event")
Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
ojeda pushed a commit that referenced this pull request Nov 28, 2020
The test_generic_metric() missed to release entries in the pctx.  Asan
reported following leak (and more):

  Direct leak of 128 byte(s) in 1 object(s) allocated from:
    #0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
    #1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14)
    #2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497)
    #3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111
    #4 0x55f7e7341667 in expr__add_ref util/expr.c:120
    #5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783
    #6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858
    #7 0x55f7e712390b in compute_single tests/parse-metric.c:128
    #8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180
    #9 0x55f7e712446d in compute_metric tests/parse-metric.c:196
    #10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295
    #11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355
    #12 0x55f7e70be09b in run_test tests/builtin-test.c:410
    #13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
    #14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
    #15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
    #16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: 6d432c4 ("perf tools: Add test_generic_metric function")
Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
ojeda pushed a commit that referenced this pull request Nov 28, 2020
The metricgroup__add_metric() can find multiple match for a metric group
and it's possible to fail.  Also it can fail in the middle like in
resolve_metric() even for single metric.

In those cases, the intermediate list and ids will be leaked like:

  Direct leak of 3 byte(s) in 1 object(s) allocated from:
    #0 0x7f4c938f40b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
    #1 0x55f7e71c1bef in __add_metric util/metricgroup.c:683
    #2 0x55f7e71c31d0 in add_metric util/metricgroup.c:906
    #3 0x55f7e71c3844 in metricgroup__add_metric util/metricgroup.c:940
    #4 0x55f7e71c488d in metricgroup__add_metric_list util/metricgroup.c:993
    #5 0x55f7e71c488d in parse_groups util/metricgroup.c:1045
    #6 0x55f7e71c60a4 in metricgroup__parse_groups_test util/metricgroup.c:1087
    #7 0x55f7e71235ae in __compute_metric tests/parse-metric.c:164
    #8 0x55f7e7124650 in compute_metric tests/parse-metric.c:196
    #9 0x55f7e7124650 in test_recursion_fail tests/parse-metric.c:318
    #10 0x55f7e7124650 in test__parse_metric tests/parse-metric.c:356
    #11 0x55f7e70be09b in run_test tests/builtin-test.c:410
    #12 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
    #13 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
    #14 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
    #15 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #16 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #17 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #18 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #19 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: 83de0b7 ("perf metric: Collect referenced metrics in struct metric_ref_node")
Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
@ojeda ojeda added required • lib Related to the `rust/` library. labels Nov 28, 2020
alex added a commit that referenced this pull request Jan 22, 2021
alex added a commit that referenced this pull request Jan 22, 2021
@alex alex mentioned this pull request Jan 22, 2021
alex added a commit that referenced this pull request Jan 22, 2021
alex added a commit that referenced this pull request Jan 22, 2021
alex added a commit that referenced this pull request Jan 22, 2021
alex added a commit that referenced this pull request Jan 22, 2021
alex added a commit that referenced this pull request Jan 23, 2021
alex added a commit that referenced this pull request Jan 23, 2021
@alex alex closed this in #81 Jan 23, 2021
@ojeda ojeda deleted the this-module branch January 23, 2021 19:46
ojeda pushed a commit that referenced this pull request Mar 15, 2021
The evlist and the cpu/thread maps should be released together.
Otherwise following error was reported by Asan.

Note that this test still has memory leaks in DSOs so it still fails
even after this change.  I'll take a look at that too.

  # perf test -v 26
  26: Object code reading                        :
  --- start ---
  test child forked, pid 154184
  Looking at the vmlinux_path (8 entries long)
  symsrc__init: build id mismatch for vmlinux.
  symsrc__init: cannot get elf header.
  Using /proc/kcore for kernel data
  Using /proc/kallsyms for symbols
  Parsing event 'cycles'
  mmap size 528384B
  ...
  =================================================================
  ==154184==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 439 byte(s) in 1 object(s) allocated from:
    #0 0x7fcb66e77037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x55ad9b7e821e in dso__new_id util/dso.c:1256
    #2 0x55ad9b8cfd4a in __machine__addnew_vdso util/vdso.c:132
    #3 0x55ad9b8cfd4a in machine__findnew_vdso util/vdso.c:347
    #4 0x55ad9b845b7e in map__new util/map.c:176
    #5 0x55ad9b8415a2 in machine__process_mmap2_event util/machine.c:1787
    #6 0x55ad9b8fab16 in perf_tool__process_synth_event util/synthetic-events.c:64
    #7 0x55ad9b8fab16 in perf_event__synthesize_mmap_events util/synthetic-events.c:499
    #8 0x55ad9b8fbfdf in __event__synthesize_thread util/synthetic-events.c:741
    #9 0x55ad9b8ff3e3 in perf_event__synthesize_thread_map util/synthetic-events.c:833
    #10 0x55ad9b738585 in do_test_code_reading tests/code-reading.c:608
    #11 0x55ad9b73b25d in test__code_reading tests/code-reading.c:722
    #12 0x55ad9b6f28fb in run_test tests/builtin-test.c:428
    #13 0x55ad9b6f28fb in test_and_print tests/builtin-test.c:458
    #14 0x55ad9b6f4a53 in __cmd_test tests/builtin-test.c:679
    #15 0x55ad9b6f4a53 in cmd_test tests/builtin-test.c:825
    #16 0x55ad9b760cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #17 0x55ad9b5eaa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #18 0x55ad9b5eaa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #19 0x55ad9b5eaa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #20 0x7fcb669acd09 in __libc_start_main ../csu/libc-start.c:308

    ...
  SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Object code reading: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
JoseTeuttli pushed a commit to JoseTeuttli/linux that referenced this pull request Jun 14, 2021
Paul E.  McKenney reported [1] that commit 1f0723a ("mm, slub: enable
slub_debug static key when creating cache with explicit debug flags")
results in the lockdep complaint:

 ======================================================
 WARNING: possible circular locking dependency detected
 5.12.0+ Rust-for-Linux#15 Not tainted
 ------------------------------------------------------
 rcu_torture_sta/109 is trying to acquire lock:
 ffffffff96063cd0 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0x9/0x20

 but task is already holding lock:
 ffffffff96173c28 (slab_mutex){+.+.}-{3:3}, at: kmem_cache_create_usercopy+0x2d/0x250

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (slab_mutex){+.+.}-{3:3}:
        lock_acquire+0xb9/0x3a0
        __mutex_lock+0x8d/0x920
        slub_cpu_dead+0x15/0xf0
        cpuhp_invoke_callback+0x17a/0x7c0
        cpuhp_invoke_callback_range+0x3b/0x80
        _cpu_down+0xdf/0x2a0
        cpu_down+0x2c/0x50
        device_offline+0x82/0xb0
        remove_cpu+0x1a/0x30
        torture_offline+0x80/0x140
        torture_onoff+0x147/0x260
        kthread+0x10a/0x140
        ret_from_fork+0x22/0x30

 -> #0 (cpu_hotplug_lock){++++}-{0:0}:
        check_prev_add+0x8f/0xbf0
        __lock_acquire+0x13f0/0x1d80
        lock_acquire+0xb9/0x3a0
        cpus_read_lock+0x21/0xa0
        static_key_enable+0x9/0x20
        __kmem_cache_create+0x38d/0x430
        kmem_cache_create_usercopy+0x146/0x250
        kmem_cache_create+0xd/0x10
        rcu_torture_stats+0x79/0x280
        kthread+0x10a/0x140
        ret_from_fork+0x22/0x30

 other info that might help us debug this:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(slab_mutex);
                                lock(cpu_hotplug_lock);
                                lock(slab_mutex);
   lock(cpu_hotplug_lock);

  *** DEADLOCK ***

 1 lock held by rcu_torture_sta/109:
  #0: ffffffff96173c28 (slab_mutex){+.+.}-{3:3}, at: kmem_cache_create_usercopy+0x2d/0x250

 stack backtrace:
 CPU: 3 PID: 109 Comm: rcu_torture_sta Not tainted 5.12.0+ Rust-for-Linux#15
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
 Call Trace:
  dump_stack+0x6d/0x89
  check_noncircular+0xfe/0x110
  ? lock_is_held_type+0x98/0x110
  check_prev_add+0x8f/0xbf0
  __lock_acquire+0x13f0/0x1d80
  lock_acquire+0xb9/0x3a0
  ? static_key_enable+0x9/0x20
  ? mark_held_locks+0x49/0x70
  cpus_read_lock+0x21/0xa0
  ? static_key_enable+0x9/0x20
  static_key_enable+0x9/0x20
  __kmem_cache_create+0x38d/0x430
  kmem_cache_create_usercopy+0x146/0x250
  ? rcu_torture_stats_print+0xd0/0xd0
  kmem_cache_create+0xd/0x10
  rcu_torture_stats+0x79/0x280
  ? rcu_torture_stats_print+0xd0/0xd0
  kthread+0x10a/0x140
  ? kthread_park+0x80/0x80
  ret_from_fork+0x22/0x30

This is because there's one order of locking from the hotplug callbacks:

lock(cpu_hotplug_lock); // from hotplug machinery itself
lock(slab_mutex); // in e.g. slab_mem_going_offline_callback()

And commit 1f0723a made the reverse sequence possible:
lock(slab_mutex); // in kmem_cache_create_usercopy()
lock(cpu_hotplug_lock); // kmem_cache_open() -> static_key_enable()

The simplest fix is to move static_key_enable() to a place before slab_mutex is
taken. That means kmem_cache_create_usercopy() in mm/slab_common.c which is not
ideal for SLUB-specific code, but the #ifdef CONFIG_SLUB_DEBUG makes it
at least self-contained and obvious.

[1] https://lore.kernel.org/lkml/20210502171827.GA3670492@paulmck-ThinkPad-P17-Gen-1/

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 1f0723a ("mm, slub: enable slub_debug static key when creating cache with explicit debug flags")
Signed-off-by: Vlastimil Babka <[email protected]>
Reported-by: Paul E. McKenney <[email protected]>
Tested-by: Paul E. McKenney <[email protected]>
Acked-by: David Rientjes <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
AltF02 pushed a commit to AltF02/linux that referenced this pull request Oct 5, 2021
It's later supposed to be either a correct address or NULL. Without the
initialization, it may contain an undefined value which results in the
following segmentation fault:

  # perf top --sort comm -g --ignore-callees=do_idle

terminates with:

  #0  0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6
  Rust-for-Linux#1  0x00007ffff55e3802 in strdup () from /lib64/libc.so.6
  Rust-for-Linux#2  0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489
  Rust-for-Linux#3  hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564
  Rust-for-Linux#4  0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420,
      sample_self=sample_self@entry=true) at util/hist.c:657
  Rust-for-Linux#5  0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0,
      sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288
  Rust-for-Linux#6  0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38)
      at util/hist.c:1056
  Rust-for-Linux#7  iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056
  Rust-for-Linux#8  0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0)
      at util/hist.c:1231
  Rust-for-Linux#9  0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0)
      at builtin-top.c:842
  Rust-for-Linux#10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202
  Rust-for-Linux#11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244
  Rust-for-Linux#12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323
  Rust-for-Linux#13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339
  Rust-for-Linux#14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341
  Rust-for-Linux#15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339
  Rust-for-Linux#16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114
  Rust-for-Linux#17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0
  Rust-for-Linux#18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6

If you look at the frame Rust-for-Linux#2, the code is:

488	 if (he->srcline) {
489          he->srcline = strdup(he->srcline);
490          if (he->srcline == NULL)
491              goto err_rawdata;
492	 }

If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish),
it gets strdupped and strdupping a rubbish random string causes the problem.

Also, if you look at the commit 1fb7d06, it adds the srcline property
into the struct, but not initializing it everywhere needed.

Committer notes:

Now I see, when using --ignore-callees=do_idle we end up here at line
2189 in add_callchain_ip():

2181         if (al.sym != NULL) {
2182                 if (perf_hpp_list.parent && !*parent &&
2183                     symbol__match_regex(al.sym, &parent_regex))
2184                         *parent = al.sym;
2185                 else if (have_ignore_callees && root_al &&
2186                   symbol__match_regex(al.sym, &ignore_callees_regex)) {
2187                         /* Treat this symbol as the root,
2188                            forgetting its callees. */
2189                         *root_al = al;
2190                         callchain_cursor_reset(cursor);
2191                 }
2192         }

And the al that doesn't have the ->srcline field initialized will be
copied to the root_al, so then, back to:

1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
1212                          int max_stack_depth, void *arg)
1213 {
1214         int err, err2;
1215         struct map *alm = NULL;
1216
1217         if (al)
1218                 alm = map__get(al->map);
1219
1220         err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent,
1221                                         iter->evsel, al, max_stack_depth);
1222         if (err) {
1223                 map__put(alm);
1224                 return err;
1225         }
1226
1227         err = iter->ops->prepare_entry(iter, al);
1228         if (err)
1229                 goto out;
1230
1231         err = iter->ops->add_single_entry(iter, al);
1232         if (err)
1233                 goto out;
1234

That al at line 1221 is what hist_entry_iter__add() (called from
sample__resolve_callchain()) saw as 'root_al', and then:

        iter->ops->add_single_entry(iter, al);

will go on with al->srcline with a bogus value, I'll add the above
sequence to the cset and apply, thanks!

Signed-off-by: Michael Petlan <[email protected]>
CC: Milian Wolff <[email protected]>
Cc: Jiri Olsa <[email protected]>
Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries")
Link: https //lore.kernel.org/r/[email protected]
Reported-by: Juri Lelli <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
ojeda pushed a commit that referenced this pull request Oct 26, 2021
This reverts commit aae74ff,
since it prevents my AMD Milan system from booting, with:

[   27.189558] BUG: kernel NULL pointer dereference, address: 0000000000000000
[   27.197506] #PF: supervisor write access in kernel mode
[   27.203333] #PF: error_code(0x0002) - not-present page
[   27.209064] PGD 0 P4D 0
[   27.211885] Oops: 0002 [#1] PREEMPT SMP NOPTI
[   27.216744] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.0-rc6+ #15
[   27.223928] Hardware name: AMD Corporation ETHANOL_X/ETHANOL_X, BIOS RXM1006B 08/20/2021
[   27.232955] RIP: 0010:run_timer_softirq+0x38b/0x4a0
[   27.238397] Code: 4c 89 f7 e8 37 27 ac 00 49 c7 46 08 00 00 00 00 49 8b 04 24 48 85 c0 74 71 4d 8b 3c 24 4d 89 7e 08 66 90 49 8b 07 49 8b 57 08 <48> 89 02 48 85 c0 74 04 48 89 50 08 49 8b 77 18 41 f6 47 22 20 4c
[   27.259350] RSP: 0018:ffffc42d00003ee8 EFLAGS: 00010086
[   27.265176] RAX: dead000000000122 RBX: 0000000000000000 RCX: 0000000000000101
[   27.273134] RDX: 0000000000000000 RSI: 0000000000000087 RDI: 0000000000000001
[   27.281084] RBP: ffffc42d00003f70 R08: 0000000000000000 R09: 00000000000003eb
[   27.289043] R10: ffffa0860cb300d0 R11: ffffa0c44de290b0 R12: ffffc42d00003ef8
[   27.297002] R13: 00000000fffef200 R14: ffffa0c44de18dc0 R15: ffffa0867a882350
[   27.304961] FS:  0000000000000000(0000) GS:ffffa0c44de00000(0000) knlGS:0000000000000000
[   27.313988] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   27.320396] CR2: 0000000000000000 CR3: 000000014569c001 CR4: 0000000000770ef0
[   27.328346] PKRU: 55555554
[   27.331359] Call Trace:
[   27.334073]  <IRQ>
[   27.336314]  ? __queue_work+0x420/0x420
[   27.340589]  ? lapic_next_event+0x21/0x30
[   27.345060]  ? clockevents_program_event+0x8f/0xe0
[   27.350402]  __do_softirq+0xfb/0x2db
[   27.354388]  irq_exit_rcu+0x98/0xd0
[   27.358275]  sysvec_apic_timer_interrupt+0xac/0xd0
[   27.363620]  </IRQ>
[   27.365955]  asm_sysvec_apic_timer_interrupt+0x12/0x20
[   27.371685] RIP: 0010:cpuidle_enter_state+0xcc/0x390
[   27.377292] Code: 3d 01 79 0a 50 e8 44 ed 77 ff 49 89 c6 0f 1f 44 00 00 31 ff e8 f5 f8 77 ff 80 7d d7 00 0f 85 e6 01 00 00 fb 66 0f 1f 44 00 00 <45> 85 ff 0f 88 17 01 00 00 49 63 c7 4c 2b 75 c8 48 8d 14 40 48 8d
[   27.398243] RSP: 0018:ffffffffb0e03dc8 EFLAGS: 00000246
[   27.404069] RAX: ffffa0c44de00000 RBX: 0000000000000001 RCX: 000000000000001f
[   27.412028] RDX: 0000000000000000 RSI: ffffffffb0bafc1f RDI: ffffffffb0bbdb81
[   27.419986] RBP: ffffffffb0e03e00 R08: 00000006549f8f3f R09: ffffffffb1065200
[   27.427935] R10: ffffa0c44de27ae4 R11: ffffa0c44de27ac4 R12: ffffa0c5634cb000
[   27.435894] R13: ffffffffb1065200 R14: 00000006549f8f3f R15: 0000000000000001
[   27.443854]  ? cpuidle_enter_state+0xbb/0x390
[   27.448712]  cpuidle_enter+0x2e/0x40
[   27.452695]  call_cpuidle+0x23/0x40
[   27.456584]  do_idle+0x1f0/0x270
[   27.460181]  cpu_startup_entry+0x20/0x30
[   27.464553]  rest_init+0xd4/0xe0
[   27.468149]  arch_call_rest_init+0xe/0x1b
[   27.472619]  start_kernel+0x6bc/0x6e2
[   27.476764]  x86_64_start_reservations+0x24/0x26
[   27.481912]  x86_64_start_kernel+0x75/0x79
[   27.486477]  secondary_startup_64_no_verify+0xb0/0xbb
[   27.492111] Modules linked in: kvm_amd(+) kvm ipmi_si(+) ipmi_devintf rapl wmi_bmof ipmi_msghandler input_leds ccp k10temp mac_hid sch_fq_codel msr ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear ast i2c_algo_bit drm_vram_helper drm_ttm_helper ttm drm_kms_helper crct10dif_pclmul crc32_pclmul ghash_clmulni_intel syscopyarea aesni_intel sysfillrect crypto_simd sysimgblt fb_sys_fops cryptd hid_generic cec nvme ahci usbhid drm e1000e nvme_core hid libahci i2c_piix4 wmi
[   27.551789] CR2: 0000000000000000
[   27.555482] ---[ end trace 897987dfe93dccc6 ]---
[   27.560630] RIP: 0010:run_timer_softirq+0x38b/0x4a0
[   27.566069] Code: 4c 89 f7 e8 37 27 ac 00 49 c7 46 08 00 00 00 00 49 8b 04 24 48 85 c0 74 71 4d 8b 3c 24 4d 89 7e 08 66 90 49 8b 07 49 8b 57 08 <48> 89 02 48 85 c0 74 04 48 89 50 08 49 8b 77 18 41 f6 47 22 20 4c
[   27.587021] RSP: 0018:ffffc42d00003ee8 EFLAGS: 00010086
[   27.592848] RAX: dead000000000122 RBX: 0000000000000000 RCX: 0000000000000101
[   27.600808] RDX: 0000000000000000 RSI: 0000000000000087 RDI: 0000000000000001
[   27.608765] RBP: ffffc42d00003f70 R08: 0000000000000000 R09: 00000000000003eb
[   27.616716] R10: ffffa0860cb300d0 R11: ffffa0c44de290b0 R12: ffffc42d00003ef8
[   27.624673] R13: 00000000fffef200 R14: ffffa0c44de18dc0 R15: ffffa0867a882350
[   27.632624] FS:  0000000000000000(0000) GS:ffffa0c44de00000(0000) knlGS:0000000000000000
[   27.641650] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   27.648159] CR2: 0000000000000000 CR3: 000000014569c001 CR4: 0000000000770ef0
[   27.656119] PKRU: 55555554
[   27.659133] Kernel panic - not syncing: Fatal exception in interrupt
[   29.030411] Shutting down cpus with NMI
[   29.034699] Kernel Offset: 0x2e600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[   29.046790] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Since unreliable, found by bisecting for KASAN's use-after-free in
enqueue_timer+0x4f/0x1e0, where the timer callback is called.

Reported-by: Kim Phillips <[email protected]>
Signed-off-by: Kim Phillips <[email protected]>
Fixes: aae74ff ("drm/ast: Add detect function support")
Link: https://lore.kernel.org/lkml/[email protected]/
Cc: Ainux <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: David Airlie <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Chuck Lever III <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Jon Grimm <[email protected]>
Cc: dri-devel <[email protected]>
Cc: linux-kernel <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
ojeda pushed a commit that referenced this pull request Nov 29, 2021
…elect()

In resp_mode_select() sanity check the block descriptor len to avoid UAF.

BUG: KASAN: use-after-free in resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509
Read of size 1 at addr ffff888026670f50 by task scsicmd/15032

CPU: 1 PID: 15032 Comm: scsicmd Not tainted 5.15.0-01d0625 #15
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
Call Trace:
 <TASK>
 dump_stack_lvl+0x89/0xb5 lib/dump_stack.c:107
 print_address_description.constprop.9+0x28/0x160 mm/kasan/report.c:257
 kasan_report.cold.14+0x7d/0x117 mm/kasan/report.c:443
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509
 schedule_resp+0x4af/0x1a10 drivers/scsi/scsi_debug.c:5483
 scsi_debug_queuecommand+0x8c9/0x1e70 drivers/scsi/scsi_debug.c:7537
 scsi_queue_rq+0x16b4/0x2d10 drivers/scsi/scsi_lib.c:1521
 blk_mq_dispatch_rq_list+0xb9b/0x2700 block/blk-mq.c:1640
 __blk_mq_sched_dispatch_requests+0x28f/0x590 block/blk-mq-sched.c:325
 blk_mq_sched_dispatch_requests+0x105/0x190 block/blk-mq-sched.c:358
 __blk_mq_run_hw_queue+0xe5/0x150 block/blk-mq.c:1762
 __blk_mq_delay_run_hw_queue+0x4f8/0x5c0 block/blk-mq.c:1839
 blk_mq_run_hw_queue+0x18d/0x350 block/blk-mq.c:1891
 blk_mq_sched_insert_request+0x3db/0x4e0 block/blk-mq-sched.c:474
 blk_execute_rq_nowait+0x16b/0x1c0 block/blk-exec.c:63
 sg_common_write.isra.18+0xeb3/0x2000 drivers/scsi/sg.c:837
 sg_new_write.isra.19+0x570/0x8c0 drivers/scsi/sg.c:775
 sg_ioctl_common+0x14d6/0x2710 drivers/scsi/sg.c:941
 sg_ioctl+0xa2/0x180 drivers/scsi/sg.c:1166
 __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:52
 do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:50
 entry_SYSCALL_64_after_hwframe+0x44/0xae arch/x86/entry/entry_64.S:113

Link: https://lore.kernel.org/r/[email protected]
Reported-by: syzkaller <[email protected]>
Acked-by: Douglas Gilbert <[email protected]>
Signed-off-by: George Kennedy <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
m-falkowski1 pushed a commit to m-falkowski1/linux that referenced this pull request Nov 30, 2021
The exit function fixes a memory leak with the src field as detected by
leak sanitizer. An example of which is:

Indirect leak of 25133184 byte(s) in 207 object(s) allocated from:
    #0 0x7f199ecfe987 in __interceptor_calloc libsanitizer/asan/asan_malloc_linux.cpp:154
    Rust-for-Linux#1 0x55defe638224 in annotated_source__alloc_histograms util/annotate.c:803
    Rust-for-Linux#2 0x55defe6397e4 in symbol__hists util/annotate.c:952
    Rust-for-Linux#3 0x55defe639908 in symbol__inc_addr_samples util/annotate.c:968
    Rust-for-Linux#4 0x55defe63aa29 in hist_entry__inc_addr_samples util/annotate.c:1119
    Rust-for-Linux#5 0x55defe499a79 in hist_iter__report_callback tools/perf/builtin-report.c:182
    Rust-for-Linux#6 0x55defe7a859d in hist_entry_iter__add util/hist.c:1236
    Rust-for-Linux#7 0x55defe49aa63 in process_sample_event tools/perf/builtin-report.c:315
    Rust-for-Linux#8 0x55defe731bc8 in evlist__deliver_sample util/session.c:1473
    Rust-for-Linux#9 0x55defe731e38 in machines__deliver_event util/session.c:1510
    Rust-for-Linux#10 0x55defe732a23 in perf_session__deliver_event util/session.c:1590
    Rust-for-Linux#11 0x55defe72951e in ordered_events__deliver_event util/session.c:183
    Rust-for-Linux#12 0x55defe740082 in do_flush util/ordered-events.c:244
    Rust-for-Linux#13 0x55defe7407cb in __ordered_events__flush util/ordered-events.c:323
    Rust-for-Linux#14 0x55defe740a61 in ordered_events__flush util/ordered-events.c:341
    Rust-for-Linux#15 0x55defe73837f in __perf_session__process_events util/session.c:2390
    Rust-for-Linux#16 0x55defe7385ff in perf_session__process_events util/session.c:2420
    ...

Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Martin Liška <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
ojeda pushed a commit that referenced this pull request Dec 20, 2021
Per HiFive Unmatched schematics, the card detect signal of the
micro SD card is connected to gpio pin #15, which should be
reflected in the DT via the <gpios> property, as described in
Documentation/devicetree/bindings/mmc/mmc-spi-slot.txt.

[1] https://sifive.cdn.prismic.io/sifive/6a06d6c0-6e66-49b5-8e9e-e68ce76f4192_hifive-unmatched-schematics-v3.pdf

Signed-off-by: Bin Meng <[email protected]>
Fixes: d573b55 ("riscv: dts: add initial board data for the SiFive HiFive Unmatched")
Cc: [email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>
ojeda pushed a commit that referenced this pull request Jan 30, 2022
arm32 uses software to simulate the instruction replaced
by kprobe. some instructions may be simulated by constructing
assembly functions. therefore, before executing instruction
simulation, it is necessary to construct assembly function
execution environment in C language through binding registers.
after kasan is enabled, the register binding relationship will
be destroyed, resulting in instruction simulation errors and
causing kernel panic.

the kprobe emulate instruction function is distributed in three
files: actions-common.c actions-arm.c actions-thumb.c, so disable
KASAN when compiling these files.

for example, use kprobe insert on cap_capable+20 after kasan
enabled, the cap_capable assembly code is as follows:
<cap_capable>:
e92d47f0	push	{r4, r5, r6, r7, r8, r9, sl, lr}
e1a05000	mov	r5, r0
e280006c	add	r0, r0, #108    ; 0x6c
e1a04001	mov	r4, r1
e1a06002	mov	r6, r2
e59fa090	ldr	sl, [pc, #144]  ;
ebfc7bf8	bl	c03aa4b4 <__asan_load4>
e595706c	ldr	r7, [r5, #108]  ; 0x6c
e2859014	add	r9, r5, #20
......
The emulate_ldr assembly code after enabling kasan is as follows:
c06f1384 <emulate_ldr>:
e92d47f0	push	{r4, r5, r6, r7, r8, r9, sl, lr}
e282803c	add	r8, r2, #60     ; 0x3c
e1a05000	mov	r5, r0
e7e37855	ubfx	r7, r5, #16, #4
e1a00008	mov	r0, r8
e1a09001	mov	r9, r1
e1a04002	mov	r4, r2
ebf35462	bl	c03c6530 <__asan_load4>
e357000f	cmp	r7, #15
e7e36655	ubfx	r6, r5, #12, #4
e205a00f	and	sl, r5, #15
0a000001	beq	c06f13bc <emulate_ldr+0x38>
e0840107	add	r0, r4, r7, lsl #2
ebf3545c	bl	c03c6530 <__asan_load4>
e084010a	add	r0, r4, sl, lsl #2
ebf3545a	bl	c03c6530 <__asan_load4>
e2890010	add	r0, r9, #16
ebf35458	bl	c03c6530 <__asan_load4>
e5990010	ldr	r0, [r9, #16]
e12fff30	blx	r0
e356000f	cm	r6, #15
1a000014	bne	c06f1430 <emulate_ldr+0xac>
e1a06000	mov	r6, r0
e2840040	add	r0, r4, #64     ; 0x40
......

when running in emulate_ldr to simulate the ldr instruction, panic
occurred, and the log is as follows:
Unable to handle kernel NULL pointer dereference at virtual address
00000090
pgd = ecb46400
[00000090] *pgd=2e0fa003, *pmd=00000000
Internal error: Oops: 206 [#1] SMP ARM
PC is at cap_capable+0x14/0xb0
LR is at emulate_ldr+0x50/0xc0
psr: 600d0293 sp : ecd63af8  ip : 00000004  fp : c0a7c30c
r10: 00000000  r9 : c30897f4  r8 : ecd63cd4
r7 : 0000000f  r6 : 0000000a  r5 : e59fa090  r4 : ecd63c98
r3 : c06ae294  r2 : 00000000  r1 : b7611300  r0 : bf4ec008
Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 32c5387d  Table: 2d546400  DAC: 55555555
Process bash (pid: 1643, stack limit = 0xecd60190)
(cap_capable) from (kprobe_handler+0x218/0x340)
(kprobe_handler) from (kprobe_trap_handler+0x24/0x48)
(kprobe_trap_handler) from (do_undefinstr+0x13c/0x364)
(do_undefinstr) from (__und_svc_finish+0x0/0x30)
(__und_svc_finish) from (cap_capable+0x18/0xb0)
(cap_capable) from (cap_vm_enough_memory+0x38/0x48)
(cap_vm_enough_memory) from
(security_vm_enough_memory_mm+0x48/0x6c)
(security_vm_enough_memory_mm) from
(copy_process.constprop.5+0x16b4/0x25c8)
(copy_process.constprop.5) from (_do_fork+0xe8/0x55c)
(_do_fork) from (SyS_clone+0x1c/0x24)
(SyS_clone) from (__sys_trace_return+0x0/0x10)
Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7)

Fixes: 35aa1df ("ARM kprobes: instruction single-stepping support")
Fixes: 4210157 ("ARM: 9017/2: Enable KASan for ARM")
Signed-off-by: huangshaobo <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>
ojeda pushed a commit that referenced this pull request Feb 28, 2022
As explained in commits:
74b6d7d ("net: dsa: realtek: register the MDIO bus under devres")
5135e96 ("net: dsa: don't allocate the slave_mii_bus using devres")

mdiobus_free() will panic when called from devm_mdiobus_free() <-
devres_release_all() <- __device_release_driver(), and that mdiobus was
not previously unregistered.

The mv88e6xxx is an MDIO device, so the initial set of constraints that
I thought would cause this (I2C or SPI buses which call ->remove on
->shutdown) do not apply. But there is one more which applies here.

If the DSA master itself is on a bus that calls ->remove from ->shutdown
(like dpaa2-eth, which is on the fsl-mc bus), there is a device link
between the switch and the DSA master, and device_links_unbind_consumers()
will unbind the Marvell switch driver on shutdown.

systemd-shutdown[1]: Powering off.
mv88e6085 0x0000000008b96000:00 sw_gl0: Link is Down
fsl-mc dpbp.9: Removing from iommu group 7
fsl-mc dpbp.8: Removing from iommu group 7
------------[ cut here ]------------
kernel BUG at drivers/net/phy/mdio_bus.c:677!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 5.16.5-00040-gdc05f73788e5 #15
pc : mdiobus_free+0x44/0x50
lr : devm_mdiobus_free+0x10/0x20
Call trace:
 mdiobus_free+0x44/0x50
 devm_mdiobus_free+0x10/0x20
 devres_release_all+0xa0/0x100
 __device_release_driver+0x190/0x220
 device_release_driver_internal+0xac/0xb0
 device_links_unbind_consumers+0xd4/0x100
 __device_release_driver+0x4c/0x220
 device_release_driver_internal+0xac/0xb0
 device_links_unbind_consumers+0xd4/0x100
 __device_release_driver+0x94/0x220
 device_release_driver+0x28/0x40
 bus_remove_device+0x118/0x124
 device_del+0x174/0x420
 fsl_mc_device_remove+0x24/0x40
 __fsl_mc_device_remove+0xc/0x20
 device_for_each_child+0x58/0xa0
 dprc_remove+0x90/0xb0
 fsl_mc_driver_remove+0x20/0x5c
 __device_release_driver+0x21c/0x220
 device_release_driver+0x28/0x40
 bus_remove_device+0x118/0x124
 device_del+0x174/0x420
 fsl_mc_bus_remove+0x80/0x100
 fsl_mc_bus_shutdown+0xc/0x1c
 platform_shutdown+0x20/0x30
 device_shutdown+0x154/0x330
 kernel_power_off+0x34/0x6c
 __do_sys_reboot+0x15c/0x250
 __arm64_sys_reboot+0x20/0x30
 invoke_syscall.constprop.0+0x4c/0xe0
 do_el0_svc+0x4c/0x150
 el0_svc+0x24/0xb0
 el0t_64_sync_handler+0xa8/0xb0
 el0t_64_sync+0x178/0x17c

So the same treatment must be applied to all DSA switch drivers, which
is: either use devres for both the mdiobus allocation and registration,
or don't use devres at all.

The Marvell driver already has a good structure for mdiobus removal, so
just plug in mdiobus_free and get rid of devres.

Fixes: ac3a68d ("net: phy: don't abuse devres in devm_mdiobus_register()")
Reported-by: Rafael Richter <[email protected]>
Signed-off-by: Vladimir Oltean <[email protected]>
Tested-by: Daniel Klauer <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
ojeda pushed a commit that referenced this pull request Feb 28, 2022
When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
ojeda pushed a commit that referenced this pull request Jul 11, 2022
commit 0622cab ("bonding: fix 802.3ad aggregator reselection"),
resolve case, when there is several aggregation groups in the same bond.
bond_3ad_unbind_slave will invalidate (clear) aggregator when
__agg_active_ports return zero. So, ad_clear_agg can be executed even, when
num_of_ports!=0. Than bond_3ad_unbind_slave can be executed again for,
previously cleared aggregator. NOTE: at this time bond_3ad_unbind_slave
will not update slave ports list, because lag_ports==NULL. So, here we
got slave ports, pointing to freed aggregator memory.

Fix with checking actual number of ports in group (as was before
commit 0622cab ("bonding: fix 802.3ad aggregator reselection") ),
before ad_clear_agg().

The KASAN logs are as follows:

[  767.617392] ==================================================================
[  767.630776] BUG: KASAN: use-after-free in bond_3ad_state_machine_handler+0x13dc/0x1470
[  767.638764] Read of size 2 at addr ffff00011ba9d430 by task kworker/u8:7/767
[  767.647361] CPU: 3 PID: 767 Comm: kworker/u8:7 Tainted: G           O 5.15.11 #15
[  767.655329] Hardware name: DNI AmazonGo1 A7040 board (DT)
[  767.660760] Workqueue: lacp_1 bond_3ad_state_machine_handler
[  767.666468] Call trace:
[  767.668930]  dump_backtrace+0x0/0x2d0
[  767.672625]  show_stack+0x24/0x30
[  767.675965]  dump_stack_lvl+0x68/0x84
[  767.679659]  print_address_description.constprop.0+0x74/0x2b8
[  767.685451]  kasan_report+0x1f0/0x260
[  767.689148]  __asan_load2+0x94/0xd0
[  767.692667]  bond_3ad_state_machine_handler+0x13dc/0x1470

Fixes: 0622cab ("bonding: fix 802.3ad aggregator reselection")
Co-developed-by: Maksym Glubokiy <[email protected]>
Signed-off-by: Maksym Glubokiy <[email protected]>
Signed-off-by: Yevhen Orlov <[email protected]>
Acked-by: Jay Vosburgh <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
ojeda pushed a commit that referenced this pull request Jan 16, 2023
If asked to drop a packet via TC_ACT_SHOT it is unsafe to assume that
res.class contains a valid pointer

Sample splat reported by Kyle Zeng

[    5.405624] 0: reclassify loop, rule prio 0, protocol 800
[    5.406326] ==================================================================
[    5.407240] BUG: KASAN: slab-out-of-bounds in cbq_enqueue+0x54b/0xea0
[    5.407987] Read of size 1 at addr ffff88800e3122aa by task poc/299
[    5.408731]
[    5.408897] CPU: 0 PID: 299 Comm: poc Not tainted 5.10.155+ #15
[    5.409516] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.15.0-1 04/01/2014
[    5.410439] Call Trace:
[    5.410764]  dump_stack+0x87/0xcd
[    5.411153]  print_address_description+0x7a/0x6b0
[    5.411687]  ? vprintk_func+0xb9/0xc0
[    5.411905]  ? printk+0x76/0x96
[    5.412110]  ? cbq_enqueue+0x54b/0xea0
[    5.412323]  kasan_report+0x17d/0x220
[    5.412591]  ? cbq_enqueue+0x54b/0xea0
[    5.412803]  __asan_report_load1_noabort+0x10/0x20
[    5.413119]  cbq_enqueue+0x54b/0xea0
[    5.413400]  ? __kasan_check_write+0x10/0x20
[    5.413679]  __dev_queue_xmit+0x9c0/0x1db0
[    5.413922]  dev_queue_xmit+0xc/0x10
[    5.414136]  ip_finish_output2+0x8bc/0xcd0
[    5.414436]  __ip_finish_output+0x472/0x7a0
[    5.414692]  ip_finish_output+0x5c/0x190
[    5.414940]  ip_output+0x2d8/0x3c0
[    5.415150]  ? ip_mc_finish_output+0x320/0x320
[    5.415429]  __ip_queue_xmit+0x753/0x1760
[    5.415664]  ip_queue_xmit+0x47/0x60
[    5.415874]  __tcp_transmit_skb+0x1ef9/0x34c0
[    5.416129]  tcp_connect+0x1f5e/0x4cb0
[    5.416347]  tcp_v4_connect+0xc8d/0x18c0
[    5.416577]  __inet_stream_connect+0x1ae/0xb40
[    5.416836]  ? local_bh_enable+0x11/0x20
[    5.417066]  ? lock_sock_nested+0x175/0x1d0
[    5.417309]  inet_stream_connect+0x5d/0x90
[    5.417548]  ? __inet_stream_connect+0xb40/0xb40
[    5.417817]  __sys_connect+0x260/0x2b0
[    5.418037]  __x64_sys_connect+0x76/0x80
[    5.418267]  do_syscall_64+0x31/0x50
[    5.418477]  entry_SYSCALL_64_after_hwframe+0x61/0xc6
[    5.418770] RIP: 0033:0x473bb7
[    5.418952] Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00
00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00
00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34
24 89
[    5.420046] RSP: 002b:00007fffd20eb0f8 EFLAGS: 00000246 ORIG_RAX:
000000000000002a
[    5.420472] RAX: ffffffffffffffda RBX: 00007fffd20eb578 RCX: 0000000000473bb7
[    5.420872] RDX: 0000000000000010 RSI: 00007fffd20eb110 RDI: 0000000000000007
[    5.421271] RBP: 00007fffd20eb150 R08: 0000000000000001 R09: 0000000000000004
[    5.421671] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
[    5.422071] R13: 00007fffd20eb568 R14: 00000000004fc740 R15: 0000000000000002
[    5.422471]
[    5.422562] Allocated by task 299:
[    5.422782]  __kasan_kmalloc+0x12d/0x160
[    5.423007]  kasan_kmalloc+0x5/0x10
[    5.423208]  kmem_cache_alloc_trace+0x201/0x2e0
[    5.423492]  tcf_proto_create+0x65/0x290
[    5.423721]  tc_new_tfilter+0x137e/0x1830
[    5.423957]  rtnetlink_rcv_msg+0x730/0x9f0
[    5.424197]  netlink_rcv_skb+0x166/0x300
[    5.424428]  rtnetlink_rcv+0x11/0x20
[    5.424639]  netlink_unicast+0x673/0x860
[    5.424870]  netlink_sendmsg+0x6af/0x9f0
[    5.425100]  __sys_sendto+0x58d/0x5a0
[    5.425315]  __x64_sys_sendto+0xda/0xf0
[    5.425539]  do_syscall_64+0x31/0x50
[    5.425764]  entry_SYSCALL_64_after_hwframe+0x61/0xc6
[    5.426065]
[    5.426157] The buggy address belongs to the object at ffff88800e312200
[    5.426157]  which belongs to the cache kmalloc-128 of size 128
[    5.426955] The buggy address is located 42 bytes to the right of
[    5.426955]  128-byte region [ffff88800e312200, ffff88800e312280)
[    5.427688] The buggy address belongs to the page:
[    5.427992] page:000000009875fabc refcount:1 mapcount:0
mapping:0000000000000000 index:0x0 pfn:0xe312
[    5.428562] flags: 0x100000000000200(slab)
[    5.428812] raw: 0100000000000200 dead000000000100 dead000000000122
ffff888007843680
[    5.429325] raw: 0000000000000000 0000000000100010 00000001ffffffff
ffff88800e312401
[    5.429875] page dumped because: kasan: bad access detected
[    5.430214] page->mem_cgroup:ffff88800e312401
[    5.430471]
[    5.430564] Memory state around the buggy address:
[    5.430846]  ffff88800e312180: fc fc fc fc fc fc fc fc fc fc fc fc
fc fc fc fc
[    5.431267]  ffff88800e312200: 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 fc
[    5.431705] >ffff88800e312280: fc fc fc fc fc fc fc fc fc fc fc fc
fc fc fc fc
[    5.432123]                                   ^
[    5.432391]  ffff88800e312300: 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 fc
[    5.432810]  ffff88800e312380: fc fc fc fc fc fc fc fc fc fc fc fc
fc fc fc fc
[    5.433229] ==================================================================
[    5.433648] Disabling lock debugging due to kernel taint

Fixes: 1da177e ("Linux-2.6.12-rc2")
Reported-by: Kyle Zeng <[email protected]>
Signed-off-by: Jamal Hadi Salim <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
ojeda pushed a commit that referenced this pull request Jan 16, 2023
When gvt debug fs is destroyed, need to have a sane check if drm
minor's debugfs root is still available or not, otherwise in case like
device remove through unbinding, drm minor's debugfs directory has
already been removed, then intel_gvt_debugfs_clean() would act upon
dangling pointer like below oops.

i915 0000:00:02.0: Direct firmware load for i915/gvt/vid_0x8086_did_0x1926_rid_0x0a.golden_hw_state failed with error -2
i915 0000:00:02.0: MDEV: Registered
Console: switching to colour dummy device 80x25
i915 0000:00:02.0: MDEV: Unregistering
BUG: kernel NULL pointer dereference, address: 00000000000000a0
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 2 PID: 2486 Comm: gfx-unbind.sh Tainted: G          I        6.1.0-rc8+ #15
Hardware name: Dell Inc. XPS 13 9350/0JXC1H, BIOS 1.13.0 02/10/2020
RIP: 0010:down_write+0x1f/0x90
Code: 1d ff ff 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 53 48 89 fb e8 62 c0 ff ff bf 01 00 00 00 e8 28 5e 31 ff 31 c0 ba 01 00 00 00 <f0> 48 0f b1 13 75 33 65 48 8b 04 25 c0 bd 01 00 48 89 43 08 bf 01
RSP: 0018:ffff9eb3036ffcc8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000000000a0 RCX: ffffff8100000000
RDX: 0000000000000001 RSI: 0000000000000064 RDI: ffffffffa48787a8
RBP: ffff9eb3036ffd30 R08: ffffeb1fc45a0608 R09: ffffeb1fc45a05c0
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: ffff91acc33fa328 R14: ffff91acc033f080 R15: ffff91acced533e0
FS:  00007f6947bba740(0000) GS:ffff91ae36d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a0 CR3: 00000001133a2002 CR4: 00000000003706e0
Call Trace:
 <TASK>
 simple_recursive_removal+0x9f/0x2a0
 ? start_creating.part.0+0x120/0x120
 ? _raw_spin_lock+0x13/0x40
 debugfs_remove+0x40/0x60
 intel_gvt_debugfs_clean+0x15/0x30 [kvmgt]
 intel_gvt_clean_device+0x49/0xe0 [kvmgt]
 intel_gvt_driver_remove+0x2f/0xb0
 i915_driver_remove+0xa4/0xf0
 i915_pci_remove+0x1a/0x30
 pci_device_remove+0x33/0xa0
 device_release_driver_internal+0x1b2/0x230
 unbind_store+0xe0/0x110
 kernfs_fop_write_iter+0x11b/0x1f0
 vfs_write+0x203/0x3d0
 ksys_write+0x63/0xe0
 do_syscall_64+0x37/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f6947cb5190
Code: 40 00 48 8b 15 71 9c 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d 51 24 0e 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89
RSP: 002b:00007ffcbac45a28 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007f6947cb5190
RDX: 000000000000000d RSI: 0000555e35c866a0 RDI: 0000000000000001
RBP: 0000555e35c866a0 R08: 0000000000000002 R09: 0000555e358cb97c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000001
R13: 000000000000000d R14: 0000000000000000 R15: 0000555e358cb8e0
 </TASK>
Modules linked in: kvmgt
CR2: 00000000000000a0
---[ end trace 0000000000000000 ]---

Cc: Wang, Zhi <[email protected]>
Cc: He, Yu <[email protected]>
Cc: [email protected]
Reviewed-by: Zhi Wang <[email protected]>
Fixes: bc7b0be ("drm/i915/gvt: Add basic debugfs infrastructure")
Signed-off-by: Zhenyu Wang <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
ojeda pushed a commit that referenced this pull request Apr 6, 2023
When a system with E810 with existing VFs gets rebooted the following
hang may be observed.

 Pid 1 is hung in iavf_remove(), part of a network driver:
 PID: 1        TASK: ffff965400e5a340  CPU: 24   COMMAND: "systemd-shutdow"
  #0 [ffffaad04005fa50] __schedule at ffffffff8b3239cb
  #1 [ffffaad04005fae8] schedule at ffffffff8b323e2d
  #2 [ffffaad04005fb00] schedule_hrtimeout_range_clock at ffffffff8b32cebc
  #3 [ffffaad04005fb80] usleep_range_state at ffffffff8b32c930
  #4 [ffffaad04005fbb0] iavf_remove at ffffffffc12b9b4c [iavf]
  #5 [ffffaad04005fbf0] pci_device_remove at ffffffff8add7513
  #6 [ffffaad04005fc10] device_release_driver_internal at ffffffff8af08baa
  #7 [ffffaad04005fc40] pci_stop_bus_device at ffffffff8adcc5fc
  #8 [ffffaad04005fc60] pci_stop_and_remove_bus_device at ffffffff8adcc81e
  #9 [ffffaad04005fc70] pci_iov_remove_virtfn at ffffffff8adf9429
 #10 [ffffaad04005fca8] sriov_disable at ffffffff8adf98e4
 #11 [ffffaad04005fcc8] ice_free_vfs at ffffffffc04bb2c8 [ice]
 #12 [ffffaad04005fd10] ice_remove at ffffffffc04778fe [ice]
 #13 [ffffaad04005fd38] ice_shutdown at ffffffffc0477946 [ice]
 #14 [ffffaad04005fd50] pci_device_shutdown at ffffffff8add58f1
 #15 [ffffaad04005fd70] device_shutdown at ffffffff8af05386
 #16 [ffffaad04005fd98] kernel_restart at ffffffff8a92a870
 #17 [ffffaad04005fda8] __do_sys_reboot at ffffffff8a92abd6
 #18 [ffffaad04005fee0] do_syscall_64 at ffffffff8b317159
 #19 [ffffaad04005ff08] __context_tracking_enter at ffffffff8b31b6fc
 #20 [ffffaad04005ff18] syscall_exit_to_user_mode at ffffffff8b31b50d
 #21 [ffffaad04005ff28] do_syscall_64 at ffffffff8b317169
 #22 [ffffaad04005ff50] entry_SYSCALL_64_after_hwframe at ffffffff8b40009b
     RIP: 00007f1baa5c13d7  RSP: 00007fffbcc55a98  RFLAGS: 00000202
     RAX: ffffffffffffffda  RBX: 0000000000000000  RCX: 00007f1baa5c13d7
     RDX: 0000000001234567  RSI: 0000000028121969  RDI: 00000000fee1dead
     RBP: 00007fffbcc55ca0   R8: 0000000000000000   R9: 00007fffbcc54e90
     R10: 00007fffbcc55050  R11: 0000000000000202  R12: 0000000000000005
     R13: 0000000000000000  R14: 00007fffbcc55af0  R15: 0000000000000000
     ORIG_RAX: 00000000000000a9  CS: 0033  SS: 002b

During reboot all drivers PM shutdown callbacks are invoked.
In iavf_shutdown() the adapter state is changed to __IAVF_REMOVE.
In ice_shutdown() the call chain above is executed, which at some point
calls iavf_remove(). However iavf_remove() expects the VF to be in one
of the states __IAVF_RUNNING, __IAVF_DOWN or __IAVF_INIT_FAILED. If
that's not the case it sleeps forever.
So if iavf_shutdown() gets invoked before iavf_remove() the system will
hang indefinitely because the adapter is already in state __IAVF_REMOVE.

Fix this by returning from iavf_remove() if the state is __IAVF_REMOVE,
as we already went through iavf_shutdown().

Fixes: 9745780 ("iavf: Add waiting so the port is initialized in remove")
Fixes: a841733 ("iavf: Fix race condition between iavf_shutdown and iavf_remove")
Reported-by: Marius Cornea <[email protected]>
Signed-off-by: Stefan Assmann <[email protected]>
Reviewed-by: Michal Kubiak <[email protected]>
Tested-by: Rafal Romanowski <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
ojeda pushed a commit that referenced this pull request Jul 31, 2023
When ring_buffer_swap_cpu was called during resize process,
the cpu buffer was swapped in the middle, resulting in incorrect state.
Continuing to run in the wrong state will result in oops.

This issue can be easily reproduced using the following two scripts:
/tmp # cat test1.sh
//#! /bin/sh
for i in `seq 0 100000`
do
         echo 2000 > /sys/kernel/debug/tracing/buffer_size_kb
         sleep 0.5
         echo 5000 > /sys/kernel/debug/tracing/buffer_size_kb
         sleep 0.5
done
/tmp # cat test2.sh
//#! /bin/sh
for i in `seq 0 100000`
do
        echo irqsoff > /sys/kernel/debug/tracing/current_tracer
        sleep 1
        echo nop > /sys/kernel/debug/tracing/current_tracer
        sleep 1
done
/tmp # ./test1.sh &
/tmp # ./test2.sh &

A typical oops log is as follows, sometimes with other different oops logs.

[  231.711293] WARNING: CPU: 0 PID: 9 at kernel/trace/ring_buffer.c:2026 rb_update_pages+0x378/0x3f8
[  231.713375] Modules linked in:
[  231.714735] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G        W          6.5.0-rc1-00276-g20edcec23f92 #15
[  231.716750] Hardware name: linux,dummy-virt (DT)
[  231.718152] Workqueue: events update_pages_handler
[  231.719714] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  231.721171] pc : rb_update_pages+0x378/0x3f8
[  231.722212] lr : rb_update_pages+0x25c/0x3f8
[  231.723248] sp : ffff800082b9bd50
[  231.724169] x29: ffff800082b9bd50 x28: ffff8000825f7000 x27: 0000000000000000
[  231.726102] x26: 0000000000000001 x25: fffffffffffff010 x24: 0000000000000ff0
[  231.728122] x23: ffff0000c3a0b600 x22: ffff0000c3a0b5c0 x21: fffffffffffffe0a
[  231.730203] x20: ffff0000c3a0b600 x19: ffff0000c0102400 x18: 0000000000000000
[  231.732329] x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffffe7aa8510
[  231.734212] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000002
[  231.736291] x11: ffff8000826998a8 x10: ffff800082b9baf0 x9 : ffff800081137558
[  231.738195] x8 : fffffc00030e82c8 x7 : 0000000000000000 x6 : 0000000000000001
[  231.740192] x5 : ffff0000ffbafe00 x4 : 0000000000000000 x3 : 0000000000000000
[  231.742118] x2 : 00000000000006aa x1 : 0000000000000001 x0 : ffff0000c0007208
[  231.744196] Call trace:
[  231.744892]  rb_update_pages+0x378/0x3f8
[  231.745893]  update_pages_handler+0x1c/0x38
[  231.746893]  process_one_work+0x1f0/0x468
[  231.747852]  worker_thread+0x54/0x410
[  231.748737]  kthread+0x124/0x138
[  231.749549]  ret_from_fork+0x10/0x20
[  231.750434] ---[ end trace 0000000000000000 ]---
[  233.720486] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[  233.721696] Mem abort info:
[  233.721935]   ESR = 0x0000000096000004
[  233.722283]   EC = 0x25: DABT (current EL), IL = 32 bits
[  233.722596]   SET = 0, FnV = 0
[  233.722805]   EA = 0, S1PTW = 0
[  233.723026]   FSC = 0x04: level 0 translation fault
[  233.723458] Data abort info:
[  233.723734]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[  233.724176]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[  233.724589]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[  233.725075] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000104943000
[  233.725592] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
[  233.726231] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[  233.726720] Modules linked in:
[  233.727007] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G        W          6.5.0-rc1-00276-g20edcec23f92 #15
[  233.727777] Hardware name: linux,dummy-virt (DT)
[  233.728225] Workqueue: events update_pages_handler
[  233.728655] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  233.729054] pc : rb_update_pages+0x1a8/0x3f8
[  233.729334] lr : rb_update_pages+0x154/0x3f8
[  233.729592] sp : ffff800082b9bd50
[  233.729792] x29: ffff800082b9bd50 x28: ffff8000825f7000 x27: 0000000000000000
[  233.730220] x26: 0000000000000000 x25: ffff800082a8b840 x24: ffff0000c0102418
[  233.730653] x23: 0000000000000000 x22: fffffc000304c880 x21: 0000000000000003
[  233.731105] x20: 00000000000001f4 x19: ffff0000c0102400 x18: ffff800082fcbc58
[  233.731727] x17: 0000000000000000 x16: 0000000000000001 x15: 0000000000000001
[  233.732282] x14: ffff8000825fe0c8 x13: 0000000000000001 x12: 0000000000000000
[  233.732709] x11: ffff8000826998a8 x10: 0000000000000ae0 x9 : ffff8000801b760c
[  233.733148] x8 : fefefefefefefeff x7 : 0000000000000018 x6 : ffff0000c03298c0
[  233.733553] x5 : 0000000000000002 x4 : 0000000000000000 x3 : 0000000000000000
[  233.733972] x2 : ffff0000c3a0b600 x1 : 0000000000000000 x0 : 0000000000000000
[  233.734418] Call trace:
[  233.734593]  rb_update_pages+0x1a8/0x3f8
[  233.734853]  update_pages_handler+0x1c/0x38
[  233.735148]  process_one_work+0x1f0/0x468
[  233.735525]  worker_thread+0x54/0x410
[  233.735852]  kthread+0x124/0x138
[  233.736064]  ret_from_fork+0x10/0x20
[  233.736387] Code: 92400000 910006b5 aa000021 aa0303f7 (f9400060)
[  233.736959] ---[ end trace 0000000000000000 ]---

After analysis, the seq of the error is as follows [1-5]:

int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
			int cpu_id)
{
	for_each_buffer_cpu(buffer, cpu) {
		cpu_buffer = buffer->buffers[cpu];
		//1. get cpu_buffer, aka cpu_buffer(A)
		...
		...
		schedule_work_on(cpu,
		 &cpu_buffer->update_pages_work);
		//2. 'update_pages_work' is queue on 'cpu', cpu_buffer(A) is passed to
		// update_pages_handler, do the update process, set 'update_done' in
		// complete(&cpu_buffer->update_done) and to wakeup resize process.
	//---->
		//3. Just at this moment, ring_buffer_swap_cpu is triggered,
		//cpu_buffer(A) be swaped to cpu_buffer(B), the max_buffer.
		//ring_buffer_swap_cpu is called as the 'Call trace' below.

		Call trace:
		 dump_backtrace+0x0/0x2f8
		 show_stack+0x18/0x28
		 dump_stack+0x12c/0x188
		 ring_buffer_swap_cpu+0x2f8/0x328
		 update_max_tr_single+0x180/0x210
		 check_critical_timing+0x2b4/0x2c8
		 tracer_hardirqs_on+0x1c0/0x200
		 trace_hardirqs_on+0xec/0x378
		 el0_svc_common+0x64/0x260
		 do_el0_svc+0x90/0xf8
		 el0_svc+0x20/0x30
		 el0_sync_handler+0xb0/0xb8
		 el0_sync+0x180/0x1c0
	//<----

	/* wait for all the updates to complete */
	for_each_buffer_cpu(buffer, cpu) {
		cpu_buffer = buffer->buffers[cpu];
		//4. get cpu_buffer, cpu_buffer(B) is used in the following process,
		//the state of cpu_buffer(A) and cpu_buffer(B) is totally wrong.
		//for example, cpu_buffer(A)->update_done will leave be set 1, and will
		//not 'wait_for_completion' at the next resize round.
		  if (!cpu_buffer->nr_pages_to_update)
			continue;

		if (cpu_online(cpu))
			wait_for_completion(&cpu_buffer->update_done);
		cpu_buffer->nr_pages_to_update = 0;
	}
	...
}
	//5. the state of cpu_buffer(A) and cpu_buffer(B) is totally wrong,
	//Continuing to run in the wrong state, then oops occurs.

Link: https://lore.kernel.org/linux-trace-kernel/[email protected]

Signed-off-by: Chen Lin <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
ojeda pushed a commit that referenced this pull request Aug 7, 2023
The cited commit holds encap tbl lock unconditionally when setting
up dests. But it may cause the following deadlock:

 PID: 1063722  TASK: ffffa062ca5d0000  CPU: 13   COMMAND: "handler8"
  #0 [ffffb14de05b7368] __schedule at ffffffffa1d5aa91
  #1 [ffffb14de05b7410] schedule at ffffffffa1d5afdb
  #2 [ffffb14de05b7430] schedule_preempt_disabled at ffffffffa1d5b528
  #3 [ffffb14de05b7440] __mutex_lock at ffffffffa1d5d6cb
  #4 [ffffb14de05b74e8] mutex_lock_nested at ffffffffa1d5ddeb
  #5 [ffffb14de05b74f8] mlx5e_tc_tun_encap_dests_set at ffffffffc12f2096 [mlx5_core]
  #6 [ffffb14de05b7568] post_process_attr at ffffffffc12d9fc5 [mlx5_core]
  #7 [ffffb14de05b75a0] mlx5e_tc_add_fdb_flow at ffffffffc12de877 [mlx5_core]
  #8 [ffffb14de05b75f0] __mlx5e_add_fdb_flow at ffffffffc12e0eef [mlx5_core]
  #9 [ffffb14de05b7660] mlx5e_tc_add_flow at ffffffffc12e12f7 [mlx5_core]
 #10 [ffffb14de05b76b8] mlx5e_configure_flower at ffffffffc12e1686 [mlx5_core]
 #11 [ffffb14de05b7720] mlx5e_rep_indr_offload at ffffffffc12e3817 [mlx5_core]
 #12 [ffffb14de05b7730] mlx5e_rep_indr_setup_tc_cb at ffffffffc12e388a [mlx5_core]
 #13 [ffffb14de05b7740] tc_setup_cb_add at ffffffffa1ab2ba8
 #14 [ffffb14de05b77a0] fl_hw_replace_filter at ffffffffc0bdec2f [cls_flower]
 #15 [ffffb14de05b7868] fl_change at ffffffffc0be6caa [cls_flower]
 #16 [ffffb14de05b7908] tc_new_tfilter at ffffffffa1ab71f0

[1031218.028143]  wait_for_completion+0x24/0x30
[1031218.028589]  mlx5e_update_route_decap_flows+0x9a/0x1e0 [mlx5_core]
[1031218.029256]  mlx5e_tc_fib_event_work+0x1ad/0x300 [mlx5_core]
[1031218.029885]  process_one_work+0x24e/0x510

Actually no need to hold encap tbl lock if there is no encap action.
Fix it by checking if encap action exists or not before holding
encap tbl lock.

Fixes: 37c3b9f ("net/mlx5e: Prevent encap offload when neigh update is running")
Signed-off-by: Chris Mi <[email protected]>
Reviewed-by: Vlad Buslov <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>
ojeda pushed a commit that referenced this pull request Aug 7, 2023
For IP tunnel encapsulation in ECMP (Equal-Cost Multipath) mode, as
the flow is duplicated to the peer eswitch, the related neighbour
information on the peer uplink representor is created as well.

In the cited commit, eswitch devcom unpair is moved to uplink unload
API, specifically the profile->cleanup_tx. If there is a encap rule
offloaded in ECMP mode, when one eswitch does unpair (because of
unloading the driver, for instance), and the peer rule from the peer
eswitch is going to be deleted, the use-after-free error is triggered
while accessing neigh info, as it is already cleaned up in uplink's
profile->disable, which is before its profile->cleanup_tx.

To fix this issue, move the neigh cleanup to profile's cleanup_tx
callback, and after mlx5e_cleanup_uplink_rep_tx is called. The neigh
init is moved to init_tx for symmeter.

[ 2453.376299] BUG: KASAN: slab-use-after-free in mlx5e_rep_neigh_entry_release+0x109/0x3a0 [mlx5_core]
[ 2453.379125] Read of size 4 at addr ffff888127af9008 by task modprobe/2496

[ 2453.381542] CPU: 7 PID: 2496 Comm: modprobe Tainted: G    B              6.4.0-rc7+ #15
[ 2453.383386] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[ 2453.384335] Call Trace:
[ 2453.384625]  <TASK>
[ 2453.384891]  dump_stack_lvl+0x33/0x50
[ 2453.385285]  print_report+0xc2/0x610
[ 2453.385667]  ? __virt_addr_valid+0xb1/0x130
[ 2453.386091]  ? mlx5e_rep_neigh_entry_release+0x109/0x3a0 [mlx5_core]
[ 2453.386757]  kasan_report+0xae/0xe0
[ 2453.387123]  ? mlx5e_rep_neigh_entry_release+0x109/0x3a0 [mlx5_core]
[ 2453.387798]  mlx5e_rep_neigh_entry_release+0x109/0x3a0 [mlx5_core]
[ 2453.388465]  mlx5e_rep_encap_entry_detach+0xa6/0xe0 [mlx5_core]
[ 2453.389111]  mlx5e_encap_dealloc+0xa7/0x100 [mlx5_core]
[ 2453.389706]  mlx5e_tc_tun_encap_dests_unset+0x61/0xb0 [mlx5_core]
[ 2453.390361]  mlx5_free_flow_attr_actions+0x11e/0x340 [mlx5_core]
[ 2453.391015]  ? complete_all+0x43/0xd0
[ 2453.391398]  ? free_flow_post_acts+0x38/0x120 [mlx5_core]
[ 2453.392004]  mlx5e_tc_del_fdb_flow+0x4ae/0x690 [mlx5_core]
[ 2453.392618]  mlx5e_tc_del_fdb_peers_flow+0x308/0x370 [mlx5_core]
[ 2453.393276]  mlx5e_tc_clean_fdb_peer_flows+0xf5/0x140 [mlx5_core]
[ 2453.393925]  mlx5_esw_offloads_unpair+0x86/0x540 [mlx5_core]
[ 2453.394546]  ? mlx5_esw_offloads_set_ns_peer.isra.0+0x180/0x180 [mlx5_core]
[ 2453.395268]  ? down_write+0xaa/0x100
[ 2453.395652]  mlx5_esw_offloads_devcom_event+0x203/0x530 [mlx5_core]
[ 2453.396317]  mlx5_devcom_send_event+0xbb/0x190 [mlx5_core]
[ 2453.396917]  mlx5_esw_offloads_devcom_cleanup+0xb0/0xd0 [mlx5_core]
[ 2453.397582]  mlx5e_tc_esw_cleanup+0x42/0x120 [mlx5_core]
[ 2453.398182]  mlx5e_rep_tc_cleanup+0x15/0x30 [mlx5_core]
[ 2453.398768]  mlx5e_cleanup_rep_tx+0x6c/0x80 [mlx5_core]
[ 2453.399367]  mlx5e_detach_netdev+0xee/0x120 [mlx5_core]
[ 2453.399957]  mlx5e_netdev_change_profile+0x84/0x170 [mlx5_core]
[ 2453.400598]  mlx5e_vport_rep_unload+0xe0/0xf0 [mlx5_core]
[ 2453.403781]  mlx5_eswitch_unregister_vport_reps+0x15e/0x190 [mlx5_core]
[ 2453.404479]  ? mlx5_eswitch_register_vport_reps+0x200/0x200 [mlx5_core]
[ 2453.405170]  ? up_write+0x39/0x60
[ 2453.405529]  ? kernfs_remove_by_name_ns+0xb7/0xe0
[ 2453.405985]  auxiliary_bus_remove+0x2e/0x40
[ 2453.406405]  device_release_driver_internal+0x243/0x2d0
[ 2453.406900]  ? kobject_put+0x42/0x2d0
[ 2453.407284]  bus_remove_device+0x128/0x1d0
[ 2453.407687]  device_del+0x240/0x550
[ 2453.408053]  ? waiting_for_supplier_show+0xe0/0xe0
[ 2453.408511]  ? kobject_put+0xfa/0x2d0
[ 2453.408889]  ? __kmem_cache_free+0x14d/0x280
[ 2453.409310]  mlx5_rescan_drivers_locked.part.0+0xcd/0x2b0 [mlx5_core]
[ 2453.409973]  mlx5_unregister_device+0x40/0x50 [mlx5_core]
[ 2453.410561]  mlx5_uninit_one+0x3d/0x110 [mlx5_core]
[ 2453.411111]  remove_one+0x89/0x130 [mlx5_core]
[ 2453.411628]  pci_device_remove+0x59/0xf0
[ 2453.412026]  device_release_driver_internal+0x243/0x2d0
[ 2453.412511]  ? parse_option_str+0x14/0x90
[ 2453.412915]  driver_detach+0x7b/0xf0
[ 2453.413289]  bus_remove_driver+0xb5/0x160
[ 2453.413685]  pci_unregister_driver+0x3f/0xf0
[ 2453.414104]  mlx5_cleanup+0xc/0x20 [mlx5_core]

Fixes: 2be5bd4 ("net/mlx5: Handle pairing of E-switch via uplink un/load APIs")
Signed-off-by: Jianbo Liu <[email protected]>
Reviewed-by: Vlad Buslov <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>
ojeda pushed a commit that referenced this pull request Aug 7, 2023
…attrs()

Running kunit test for 6.5-rc1 hits one bug:

        ok 10 damon_test_update_monitoring_result
    general protection fault, probably for non-canonical address 0x1bffa5c419cfb81: 0000 [#1] PREEMPT SMP NOPTI
    CPU: 1 PID: 110 Comm: kunit_try_catch Tainted: G                 N 6.5.0-rc2 #15
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
    RIP: 0010:damon_set_attrs+0xb9/0x120
    Code: f8 00 00 00 4c 8d 58 e0 48 39 c3 74 ba 41 ba 59 17 b7 d1 49 8b 43 10 4d
    8d 4b 10 48 8d 70 e0 49 39 c1 74 50 49 8b 40 08 31 d2 <69> 4e 18 10 27 00 00
    49 f7 30 31 d2 48 89 c5 89 c8 f7 f5 31 d2 89
    RSP: 0000:ffffc900005bfd40 EFLAGS: 00010246
    RAX: ffffffff81159fc0 RBX: ffffc900005bfeb8 RCX: 0000000000000000
    RDX: 0000000000000000 RSI: 01bffa5c419cfb69 RDI: ffffc900005bfd70
    RBP: ffffc90000013c10 R08: ffffc900005bfdc0 R09: ffffffff81ff10ed
    R10: 00000000d1b71759 R11: ffffffff81ff10dd R12: ffffc90000013a78
    R13: ffff88810eb78180 R14: ffffffff818297c0 R15: ffffc90000013c28
    FS:  0000000000000000(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000000000 CR3: 0000000002a1c001 CR4: 0000000000370ee0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     <TASK>
     damon_test_set_attrs+0x63/0x1f0
     kunit_generic_run_threadfn_adapter+0x17/0x30
     kthread+0xfd/0x130

The problem seems to be related with the damon_ctx was used without
being initialized. Fix it by adding the initialization.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: aa13779 ("mm/damon/core-test: add a test for damon_set_attrs()")
Signed-off-by: Feng Tang <[email protected]>
Reviewed-by: SeongJae Park <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
ojeda pushed a commit that referenced this pull request Sep 12, 2023
Currently, for double invoke call_rcu(), will dump rcu_head objects memory
info, if the objects is not allocated from the slab allocator, the
vmalloc_dump_obj() will be invoke and the vmap_area_lock spinlock need to
be held, since the call_rcu() can be invoked in interrupt context,
therefore, there is a possibility of spinlock deadlock scenarios.

And in Preempt-RT kernel, the rcutorture test also trigger the following
lockdep warning:

BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 1, expected: 0
RCU nest depth: 1, expected: 1
3 locks held by swapper/0/1:
 #0: ffffffffb534ee80 (fullstop_mutex){+.+.}-{4:4}, at: torture_init_begin+0x24/0xa0
 #1: ffffffffb5307940 (rcu_read_lock){....}-{1:3}, at: rcu_torture_init+0x1ec7/0x2370
 #2: ffffffffb536af40 (vmap_area_lock){+.+.}-{3:3}, at: find_vmap_area+0x1f/0x70
irq event stamp: 565512
hardirqs last  enabled at (565511): [<ffffffffb379b138>] __call_rcu_common+0x218/0x940
hardirqs last disabled at (565512): [<ffffffffb5804262>] rcu_torture_init+0x20b2/0x2370
softirqs last  enabled at (399112): [<ffffffffb36b2586>] __local_bh_enable_ip+0x126/0x170
softirqs last disabled at (399106): [<ffffffffb43fef59>] inet_register_protosw+0x9/0x1d0
Preemption disabled at:
[<ffffffffb58040c3>] rcu_torture_init+0x1f13/0x2370
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.5.0-rc4-rt2-yocto-preempt-rt+ #15
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x68/0xb0
 dump_stack+0x14/0x20
 __might_resched+0x1aa/0x280
 ? __pfx_rcu_torture_err_cb+0x10/0x10
 rt_spin_lock+0x53/0x130
 ? find_vmap_area+0x1f/0x70
 find_vmap_area+0x1f/0x70
 vmalloc_dump_obj+0x20/0x60
 mem_dump_obj+0x22/0x90
 __call_rcu_common+0x5bf/0x940
 ? debug_smp_processor_id+0x1b/0x30
 call_rcu_hurry+0x14/0x20
 rcu_torture_init+0x1f82/0x2370
 ? __pfx_rcu_torture_leak_cb+0x10/0x10
 ? __pfx_rcu_torture_leak_cb+0x10/0x10
 ? __pfx_rcu_torture_init+0x10/0x10
 do_one_initcall+0x6c/0x300
 ? debug_smp_processor_id+0x1b/0x30
 kernel_init_freeable+0x2b9/0x540
 ? __pfx_kernel_init+0x10/0x10
 kernel_init+0x1f/0x150
 ret_from_fork+0x40/0x50
 ? __pfx_kernel_init+0x10/0x10
 ret_from_fork_asm+0x1b/0x30
 </TASK>

The previous patch fixes this by using the deadlock-safe best-effort
version of find_vm_area.  However, in case of failure print the fact that
the pointer was a vmalloc pointer so that we print at least something.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 98f1808 ("mm: Make mem_dump_obj() handle vmalloc() memory")
Signed-off-by: Zqiang <[email protected]>
Signed-off-by: Joel Fernandes (Google) <[email protected]>
Reported-by: Zhen Lei <[email protected]>
Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Uladzislau Rezki (Sony) <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
fbq pushed a commit that referenced this pull request Sep 25, 2023
The following processes run into a deadlock. CPU 41 was waiting for CPU 29
to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29
was hung by that spinlock with IRQs disabled.

  PID: 17360    TASK: ffff95c1090c5c40  CPU: 41  COMMAND: "mrdiagd"
  !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0
  !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0
  !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0
   # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0
   # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0
   # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0
   # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0
   # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0
   # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0
   # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0
   #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0
   #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0
   #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0
   #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0
   #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0
   #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0
   #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0
   #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0
   #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0
   #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

  PID: 17355    TASK: ffff95c1090c3d80  CPU: 29  COMMAND: "mrdiagd"
  !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0
  !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0
   # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0
   # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0
   # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0
   # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0
   # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0
   # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0
   # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0
   # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0
   #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0
   #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0
   #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0
   #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0
   #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0
   #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0
   #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0
   #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0

The lock is used to synchronize different sysfs operations, it doesn't
protect any resource that will be touched by an interrupt. Consequently
it's not required to disable IRQs. Replace the spinlock with a mutex to fix
the deadlock.

Signed-off-by: Junxiao Bi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Cc: [email protected]
Signed-off-by: Martin K. Petersen <[email protected]>
ojeda pushed a commit that referenced this pull request Oct 5, 2023
…roy()

After the commit in Fixes:, if a module that created a slab cache does not
release all of its allocated objects before destroying the cache (at rmmod
time), we might end up releasing the kmem_cache object without removing it
from the slab_caches list thus corrupting the list as kmem_cache_destroy()
ignores the return value from shutdown_cache(), which in turn never removes
the kmem_cache object from slabs_list in case __kmem_cache_shutdown() fails
to release all of the cache's slabs.

This is easily observable on a kernel built with CONFIG_DEBUG_LIST=y
as after that ill release the system will immediately trip on list_add,
or list_del, assertions similar to the one shown below as soon as another
kmem_cache gets created, or destroyed:

  [ 1041.213632] list_del corruption. next->prev should be ffff89f596fb5768, but was 52f1e5016aeee75d. (next=ffff89f595a1b268)
  [ 1041.219165] ------------[ cut here ]------------
  [ 1041.221517] kernel BUG at lib/list_debug.c:62!
  [ 1041.223452] invalid opcode: 0000 [#1] PREEMPT SMP PTI
  [ 1041.225408] CPU: 2 PID: 1852 Comm: rmmod Kdump: loaded Tainted: G    B   W  OE      6.5.0 #15
  [ 1041.228244] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20230524-3.fc37 05/24/2023
  [ 1041.231212] RIP: 0010:__list_del_entry_valid+0xae/0xb0

Another quick way to trigger this issue, in a kernel with CONFIG_SLUB=y,
is to set slub_debug to poison the released objects and then just run
cat /proc/slabinfo after removing the module that leaks slab objects,
in which case the kernel will panic:

  [   50.954843] general protection fault, probably for non-canonical address 0xa56b6b6b6b6b6b8b: 0000 [#1] PREEMPT SMP PTI
  [   50.961545] CPU: 2 PID: 1495 Comm: cat Kdump: loaded Tainted: G    B   W  OE      6.5.0 #15
  [   50.966808] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20230524-3.fc37 05/24/2023
  [   50.972663] RIP: 0010:get_slabinfo+0x42/0xf0

This patch fixes this issue by properly checking shutdown_cache()'s
return value before taking the kmem_cache_release() branch.

Fixes: 0495e33 ("mm/slab_common: Deleting kobject in kmem_cache_destroy() without holding slab_mutex/cpu_hotplug_lock")
Signed-off-by: Rafael Aquini <[email protected]>
Cc: [email protected]
Reviewed-by: Waiman Long <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>
ojeda pushed a commit that referenced this pull request Oct 5, 2023
Fix an error detected by memory sanitizer:
```
==4033==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6
    #1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2
    #2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9
    #3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32
    #4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6
    #5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8
    #6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8
    #7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9
    #8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8
    #9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15
    #10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9
    #11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8
    #12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5
    #13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9
    #14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11
    #15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8
    #16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2
    #17 0x55fb0f941dab in main tools/perf/perf.c:535:3
```

Fixes: 7b723db ("perf pmu: Be lazy about loading event info files from sysfs")
Signed-off-by: Ian Rogers <[email protected]>
Cc: James Clark <[email protected]>
Cc: Kan Liang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
ojeda pushed a commit that referenced this pull request Dec 13, 2023
When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/[email protected]
Suggested-by: "Ismail, Mustafa" <[email protected]>
Signed-off-by: Shifeng Li <[email protected]>
Reviewed-by: Shiraz Saleem <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
fbq pushed a commit that referenced this pull request Dec 28, 2023
Petr Machata says:

====================
mlxsw: Support CFF flood mode

The registers to configure to initialize a flood table differ between the
controlled and CFF flood modes. In therefore needs to be an op. Add it,
hook up the current init to the existing families, and invoke the op.

PGT is an in-HW table that maps addresses to sets of ports. Then when some
HW process needs a set of ports as an argument, instead of embedding the
actual set in the dynamic configuration, what gets configured is the
address referencing the set. The HW then works with the appropriate PGT
entry.

Among other allocations, the PGT currently contains two large blocks for
bridge flooding: one for 802.1q and one for 802.1d. Within each of these
blocks are three tables, for unknown-unicast, multicast and broadcast
flooding:

      . . . |    802.1q    |    802.1d    | . . .
            | UC | MC | BC | UC | MC | BC |
             \______ _____/ \_____ ______/
                    v             v
                   FID flood vectors

Thus each FID (which corresponds to an 802.1d bridge or one VLAN in an
802.1q bridge) uses three flood vectors spread across a fairly large region
of PGT.

This way of organizing the flood table (called "controlled") is not very
flexible. E.g. to decrease a bridge scale and store more IP MC vectors, one
would need to completely rewrite the bridge PGT blocks, or resort to hacks
such as storing individual MC flood vectors into unused part of the bridge
table.

In order to address these shortcomings, Spectrum-2 and above support what
is called CFF flood mode, for Compressed FID Flooding. In CFF flood mode,
each FID has a little table of its own, with three entries adjacent to each
other, one for unknown-UC, one for MC, one for BC. This allows for a much
more fine-grained approach to PGT management, where bits of it are
allocated on demand.

      . . . | FID | FID | FID | FID | FID | . . .
            |U|M|B|U|M|B|U|M|B|U|M|B|U|M|B|
             \_____________ _____________/
                           v
                   FID flood vectors

Besides the FID table organization, the CFF flood mode also impacts Router
Subport (RSP) table. This table contains flood vectors for rFIDs, which are
FIDs that reference front panel ports or LAGs. The RSP table contains two
entries per front panel port and LAG, one for unknown-UC traffic, and one
for everything else. Currently, the FW allocates and manages the table in
its own part of PGT. rFIDs are marked with flood_rsp bit and managed
specially. In CFF mode, rFIDs are managed as all other FIDs. The driver
therefore has to allocate and maintain the flood vectors. Like with bridge
FIDs, this is more work, but increases flexibility of the system.

The FW currently supports both the controlled and CFF flood modes. To shed
complexity, in the future it should only support CFF flood mode. Hence this
patchset, which adds CFF flood mode support to mlxsw.

Since mlxsw needs to maintain both the controlled mode as well as CFF mode
support, we will keep the layout as compatible as possible. The bridge
tables will stay in the same overall shape, just their inner organization
will change from flood mode -> FID to FID -> flood mode. Likewise will RSP
be kept as a contiguous block of PGT memory, as was the case when the FW
maintained it.

- The way FIDs get configured under the CFF flood mode differs from the
  currently used controlled mode. The simple approach of having several
  globally visible arrays for spectrum.c to statically choose from no
  longer works.

  Patch #1 thus privatizes all FID initialization and finalization logic,
  and exposes it as ops instead.

- Patch #2 renames the ops that are specific to the controlled mode, to
  make room in the namespace for the CFF variants.

  Patch #3 extracts a helper to compute flood table base out of
  mlxsw_sp_fid_flood_table_mid().

- The op fid_setup configured fid_offset, i.e. the number of this FID
  within its family. For rFIDs in CFF mode, to determine this number, the
  driver will need to do fallible queries.

  Thus in patch #4, make the FID setup operation fallible as well.

- Flood mode initialization routine differs between the controlled and CFF
  flood modes. The controlled mode needs to configure flood table layout,
  which the CFF mode does not need to do.

  In patch #5, move mlxsw_sp_fid_flood_table_init() up so that the
  following patch can make use of it.

  In patch #6, add an op to be invoked per table (if defined).

- The current way of determining PGT allocation size depends on the number
  of FIDs and number of flood tables. RFIDs however have PGT footprint
  depending not on number of FIDs, but on number of ports and LAGs, because
  which ports an rFID should flood to does not depend on the FID itself,
  but on the port or LAG that it references.

  Therefore in patch #7, add FID family ops for determining PGT allocation
  size.

- As elaborated above, layout of PGT will differ between controlled and CFF
  flood modes. In CFF mode, it will further differ between rFIDs and other
  FIDs (as described at previous patch). The way to pack the SFMR register
  to configure a FID will likewise differ from controlled to CFF.

  Thus in patches #8 and #9 add FID family ops to determine PGT base
  address for a FID and to pack SFMR.

- Patches #10 and #11 add more bits for RSP support. In patch #10, add a
  new traffic type enumerator, for non-UC traffic. This is a combination of
  BC and MC traffic, but the way that mlxsw maps these mnemonic names to
  actual traffic type configurations requires that we have a new name to
  describe this class of traffic.

  Patch #11 then adds hooks necessary for RSP table maintenance. As ports
  come and go, and join and leave LAGs, it is necessary to update flood
  vectors that the rFIDs use. These new hooks will make that possible.

- Patches #12, #13 and #14 introduce flood profiles. These have been
  implicit so far, but the way that CFF flood mode works with profile IDs
  requires that we make them explicit.

  Thus in patch #12, introduce flood profile objects as a set of flood
  tables that FID families then refer to. The FID code currently only
  uses a single flood profile.

  In patch #13, add a flood profile ID to flood profile objects.

  In patch #14, when in CFF mode, configure SFFP according to the existing
  flood profiles (or the one that exists as of that point).

- Patches #15 and #16 add code to implement, respectively, bridge FIDs and
  RSP FIDs in CFF mode.

- In patch #17, toggle flood_mode_prefer_cff on Spectrum-2 and above, which
  makes the newly-added code live.
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
fbq pushed a commit that referenced this pull request Dec 28, 2023
…s_del_by_dev()

I got the below warning trace:

WARNING: CPU: 4 PID: 4056 at net/core/dev.c:11066 unregister_netdevice_many_notify
CPU: 4 PID: 4056 Comm: ip Not tainted 6.7.0-rc4+ #15
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:unregister_netdevice_many_notify+0x9a4/0x9b0
Call Trace:
 rtnl_dellink
 rtnetlink_rcv_msg
 netlink_rcv_skb
 netlink_unicast
 netlink_sendmsg
 __sock_sendmsg
 ____sys_sendmsg
 ___sys_sendmsg
 __sys_sendmsg
 do_syscall_64
 entry_SYSCALL_64_after_hwframe

It can be repoduced via:

    ip netns add ns1
    ip netns exec ns1 ip link add bond0 type bond mode 0
    ip netns exec ns1 ip link add bond_slave_1 type veth peer veth2
    ip netns exec ns1 ip link set bond_slave_1 master bond0
[1] ip netns exec ns1 ethtool -K bond0 rx-vlan-filter off
[2] ip netns exec ns1 ip link add link bond_slave_1 name bond_slave_1.0 type vlan id 0
[3] ip netns exec ns1 ip link add link bond0 name bond0.0 type vlan id 0
[4] ip netns exec ns1 ip link set bond_slave_1 nomaster
[5] ip netns exec ns1 ip link del veth2
    ip netns del ns1

This is all caused by command [1] turning off the rx-vlan-filter function
of bond0. The reason is the same as commit 01f4fd2 ("bonding: Fix
incorrect deletion of ETH_P_8021AD protocol vid from slaves"). Commands
[2] [3] add the same vid to slave and master respectively, causing
command [4] to empty slave->vlan_info. The following command [5] triggers
this problem.

To fix this problem, we should add VLAN_FILTER feature checks in
vlan_vids_add_by_dev() and vlan_vids_del_by_dev() to prevent incorrect
addition or deletion of vlan_vid information.

Fixes: 348a144 ("vlan: introduce functions to do mass addition/deletion of vids by another device")
Signed-off-by: Liu Jian <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>
ojeda pushed a commit that referenced this pull request Apr 29, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <[email protected]>
Reviewed-by: Willem de Bruijn <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
ojeda pushed a commit that referenced this pull request Jun 11, 2024
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: [email protected] # 6.1+
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Signed-off-by: David Sterba <[email protected]>
ojeda pushed a commit that referenced this pull request Jul 8, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Darksonn pushed a commit to Darksonn/linux that referenced this pull request Sep 23, 2024
A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  Rust-for-Linux#8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  Rust-for-Linux#9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 Rust-for-Linux#10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 Rust-for-Linux#11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 Rust-for-Linux#12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 Rust-for-Linux#13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 Rust-for-Linux#14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 Rust-for-Linux#15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 Rust-for-Linux#16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 Rust-for-Linux#17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <[email protected]>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>
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Implement THIS_MODULE
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