Re: [PATCH v2] arm64: mm: print hexadecimal EC value in mem_abort_decode()

From: Anshuman Khandual
Date: Thu Aug 08 2019 - 02:21:54 EST




On 08/08/2019 11:31 AM, Miles Chen wrote:
> On Thu, 2019-08-08 at 11:19 +0530, Anshuman Khandual wrote:
>>
>> On 08/07/2019 06:03 AM, Miles Chen wrote:
>>> This change prints the hexadecimal EC value in mem_abort_decode(),
>>> which makes it easier to lookup the corresponding EC in
>>> the ARM Architecture Reference Manual.
>>>
>>> The commit 1f9b8936f36f ("arm64: Decode information from ESR upon mem
>>> faults") prints useful information when memory abort occurs. It would
>>> be easier to lookup "0x25" instead of "DABT" in the document. Then we
>>> can check the corresponding ISS.
>>>
>>> For example:
>>> Current info Document
>>> EC Exception class
>>> "CP15 MCR/MRC" 0x3 "MCR or MRC access to CP15a..."
>>> "ASIMD" 0x7 "Access to SIMD or floating-point..."
>>> "DABT (current EL)" 0x25 "Data Abort taken without..."
>>> ...
>>>
>>> Before:
>>> Unable to handle kernel paging request at virtual address 000000000000c000
>>> Mem abort info:
>>> ESR = 0x96000046
>>> Exception class = DABT (current EL), IL = 32 bits
>>> SET = 0, FnV = 0
>>> EA = 0, S1PTW = 0
>>> Data abort info:
>>> ISV = 0, ISS = 0x00000046
>>> CM = 0, WnR = 1
>>>
>>> After:
>>> Unable to handle kernel paging request at virtual address 000000000000c000
>>> Mem abort info:
>>> ESR = 0x96000046
>>> EC = 0x25: DABT (current EL), IL = 32 bits
>>> SET = 0, FnV = 0
>>> EA = 0, S1PTW = 0
>>> Data abort info:
>>> ISV = 0, ISS = 0x00000046
>>> CM = 0, WnR = 1
>>>
>>> Change since v1:
>>> print "EC" instead of "Exception class"
>>> print EC in fixwidth
>>>
>>> Cc: Mark Rutland <Mark.rutland@xxxxxxx>
>>> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
>>> Cc: James Morse <james.morse@xxxxxxx>
>>> Signed-off-by: Miles Chen <miles.chen@xxxxxxxxxxxx>
>>
>> This version implements the suggestion, hence it should have
>> also contained acked-by tag from Mark from earlier version.
>>
>
> No problem. Sorry for not including the tag.
> I was not sure if I should add the acked-by tag from Mark in patch v2.

Yeah because V2 has now implemented the suggestion as required for
getting the tag per Mark in V1.

>
>> Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
>
> If I send patch v3, I should include acked-by tag from Mark and
> Reviewed-by tag from you, right?

Right.