[feature request] kmem -S: list full slab objects even usr tracking (SLAB_STORE_USER) is not enabled.

[changbindu]

On full slab is tracked if SLAB_STORE_USER is not enabled. So cann't get full slabs via the node 'full' list. And by now crash just print '(not tracked)' for those full slabs.

But, checking full slab objects sometimes is usefull. And we can still find them by looking up all pages with PG_slab set and the page::slab_cache matches current slab cache. Then just print all objects in them.

[crash-utility]

It is done that way by design, primarily due to time concerns to walk through the vmemmap array, especially on increasingly common systems with huge amounts of memory. It might be worth it if only one slab cache is specified, or by using another option letter in conjunction with -S. If you have a proposed patch, please post it on the crash-utility mailing list at:

https://www.redhat.com/mailman/listinfo/crash-utility

I don't accept merge requests via github.

Thanks,
Dave

[changbindu]

I don't have the patch yet. When I get a time to do that I will send it to you via maillist. Thanks.

[changbindu]

Another short solution is printing slab name for each slab page for cmd " kmem -p". Then we can check those pages manually.

I have done this work. I you agree this I will send the patch.