4.18rc3 TX2 boot failure with "ACPICA: AML parser: attempt to continue loading table after error"

[jeremy.linton@arm.com (Jeremy Linton)]

Hi,

On 07/02/2018 04:52 PM, Rafael J. Wysocki wrote:
> On Mon, Jul 2, 2018 at 11:41 PM, Jeremy Linton <jeremy.linton@arm.com> wrote:
>> Hi,
>>
>> I'm experiencing two problems with commit 5088814a6e931 which is "ACPICA:
>> AML parser: attempt to continue loading table after error"
>>
>> The first is this boot failure on a thunderX2:
>>
>> [   10.770098] ACPI Error: Ignore error and continue table load
>> (20180531/psobject-604)
>>      [   10.777926] Unable to handle kernel NULL pointer dereference at
>>      [   10.950199] Call trace:
>>      [   10.952663]  acpi_ps_peek_opcode+0x1c/0x40
>>      [   10.956797]  acpi_ps_create_op+0x54/0x278
>>      [   10.960842]  acpi_ps_parse_loop+0x1b4/0x6c8
>>      [   10.965063]  acpi_ps_parse_aml+0xe0/0x2b4
>>      [   10.969108]  acpi_ps_execute_table+0xa0/0x104
>>      [   10.973505]  acpi_ns_execute_table+0x120/0x194
>>      [   10.977989]  acpi_ns_parse_table+0x34/0x68
>>      [   10.982122]  acpi_ns_load_table+0x4c/0xbc
>>      [   10.986169]  acpi_tb_load_namespace+0x1d4/0x240
>>      [   10.990744]  acpi_load_tables+0x50/0xbc
>>      [   10.994614]  acpi_init+0xb8/0x374
>>      [   10.997959]  do_one_initcall+0x54/0x208
>>      [   11.001829]  kernel_init_freeable+0x224/0x300
>>      [   11.006229]  kernel_init+0x18/0x118
>>      [   11.009747]  ret_from_fork+0x10/0x18
>>      [   11.013354] Code: aa0003f3 aa1e03e0 d503201f f9400661 (39400020)
>>      [   11.019535] ---[ end trace 2bd8068593cf8acc ]---
>>      [   11.024195] Kernel panic - not syncing: Fatal exception
>>      [   11.029488] SMP: stopping secondary CPUs
>>      [   11.033480] ---[ end Kernel panic - not syncing: Fatal exception ]---
>>
>> Which does appear to be the result of some bad data in the table, but it was
>> working with 4.17, and reverting this commit solves the problem.
> 
> But this commit fixes another regression which was more widespread.
> 
> Apparently, we can't work around all of the errors in the tables out
> there at the same time. :-/

NP, Let me see if I can come up with a way to harden the 
parse_loop/create_op code enough that it doesn't crash the machine.

> 
>> Also the messages now newly being prefixed with '\n' are slightly corrupted
>> like:
>>
>> "3ACPI BIOS Error (bug):"
>>
>> because the KERN_XXX macro is being encoded after the CR which keeps it from
>> being processed correctly.
> 
> Yes, that's a known issue which should be fixed in -rc4.

Oh.. Yes I see that now, thanks.