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

From: Miles Chen
Date: Thu Aug 08 2019 - 02:58:50 EST


On Thu, 2019-08-08 at 11:51 +0530, Anshuman Khandual wrote:
>
> 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.
>

Understood. thanks for the explanation


> >
> >> 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.