[ARM64] failed to parse ramdump with crash 8.0.5

[byron-wang]

~/temp/0827-2$ ./crash SYS_COREDUMP vmlinux

crash 8.0.5
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crash: invalid kernel virtual address: ffffffda1ba01cc0 type: "kernel_config_data"
WARNING: cannot read kernel_config_data
crash: invalid kernel virtual address: ffffffda1c98aeb0 type: "possible"
WARNING: cannot read cpu_possible_map
crash: invalid kernel virtual address: ffffffda1c98aea8 type: "present"
WARNING: cannot read cpu_present_map
crash: invalid kernel virtual address: ffffffda1c98aea0 type: "online"
WARNING: cannot read cpu_online_map
crash: invalid kernel virtual address: ffffffda1c98aeb8 type: "active"
WARNING: cannot read cpu_active_map
crash: invalid kernel virtual address: ffffffda1cb9aa48 type: "shadow_timekeeper xtime_sec"
crash: invalid kernel virtual address: ffffffda1cb13ea0 type: "init_uts_ns"
WARNING: invalid linux_banner pointer: ffffffda1bbd3328
crash: vmlinux and SYS_COREDUMP do not match!

then, tried to modify arm64.c as below, and it worked normally. please help check it.

static int
arm64_set_va_bits_by_tcr(void)
{
	ulong value;

	if (arm64_get_vmcoreinfo(&value, "NUMBER(TCR_EL1_T1SZ)", NUM_DEC) ||     // from NUM_HEX to NUM_DEC
		arm64_get_vmcoreinfo(&value, "NUMBER(tcr_el1_t1sz)", NUM_DEC)) {     // from NUM_HEX to NUM_DEC

Thanks.

[kylee0215]

Hi,
In kernel-v6.11-rc6, the kernel uses TCR_EL1_T1SZ as hex in the following function[1].

void arch_crash_save_vmcoreinfo(void)
{
	VMCOREINFO_NUMBER(VA_BITS);
	/* Please note VMCOREINFO_NUMBER() uses "%d", not "%x" */
	vmcoreinfo_append_str("NUMBER(MODULES_VADDR)=0x%lx\n", MODULES_VADDR);
	vmcoreinfo_append_str("NUMBER(MODULES_END)=0x%lx\n", MODULES_END);
	vmcoreinfo_append_str("NUMBER(VMALLOC_END)=0x%lx\n", VMALLOC_END);
	vmcoreinfo_append_str("NUMBER(VMEMMAP_START)=0x%lx\n", VMEMMAP_START);
	vmcoreinfo_append_str("NUMBER(VMEMMAP_END)=0x%lx\n", VMEMMAP_END);
	vmcoreinfo_append_str("NUMBER(kimage_voffset)=0x%llx\n",
                    	kimage_voffset);
	vmcoreinfo_append_str("NUMBER(PHYS_OFFSET)=0x%llx\n",
                    	PHYS_OFFSET);
	vmcoreinfo_append_str("NUMBER(TCR_EL1_T1SZ)=0x%llx\n",
                    	get_tcr_el1_t1sz());

You can refer to this discussion[2] as well.

[1] https://elixir.bootlin.com/linux/v6.11-rc6/source/arch/arm64/kernel/vmcore_info.c#L33
[2] https://lists.crash-utility.osci.io/archives/list/[email protected]/thread/LUCYZ5JBGEH2R422JFPJC5IUPMDRGCRS/

[byron-wang]

Hi,

Thanks for your reply.

retrieve the vmcoreinfo from ramdump, and list the snippets as below,

NUMBER(VA_BITS)=39
NUMBER(PHYS_OFFSET)=0x40000000
NUMBER(TCR_EL1_T1SZ)=25
NUMBER(KERNELPACMASK)=0x0

the "25" has no a prefix "0x", so could it be taken as decimal during parsing， or ought to be written as hexadecimal with hex prefix here?

Thanks.