linux-kernel - Re: [PATCH 03/31] Add debugger entry points for AVR32

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Thu, 28 Jan 2016 13:20:35 -0700
From:	Jeffrey Merkey <jeffmerkey@...il.com>
To:	Hans-Christian Noren Egtvedt <egtvedt@...fundet.no>
Cc:	linux-kernel@...r.kernel.org, hskinnemoen@...il.com,
	linux.mdb@...il.com
Subject: Re: [PATCH 03/31] Add debugger entry points for AVR32

On 1/28/16, Hans-Christian Noren Egtvedt <egtvedt@...fundet.no> wrote:
> Around Thu 28 Jan 2016 12:46:17 -0700 or thereabout, Jeffrey Merkey wrote:
>> This patch series adds an export which can be set by system debuggers to
>> direct the hard lockup and soft lockup detector to trigger a breakpoint
>> exception and enter a debugger if one is active.  It is assumed that if
>> someone sets this variable, then an breakpoint handler of some sort will
>> be actively loaded or registered via the notify die handler chain.
>>
>> This addition is extremely useful for debugging hard and soft lockups
>> real time and quickly from a console debugger.
>>
>> Signed-off-by: Jeffrey Merkey <jeffmerkey@...il.com>
>
> Acked-by: Hans-Christian Egtvedt <egtvedt@...fundet.no>
>
>> ---
>>  arch/avr32/include/asm/kdebug.h | 4 ++++
>>  1 file changed, 4 insertions(+)
>>
>> diff --git a/arch/avr32/include/asm/kdebug.h
>> b/arch/avr32/include/asm/kdebug.h
>> index f930ce2..f67caf0 100644
>> --- a/arch/avr32/include/asm/kdebug.h
>> +++ b/arch/avr32/include/asm/kdebug.h
>> @@ -1,6 +1,10 @@
>>  #ifndef __ASM_AVR32_KDEBUG_H
>>  #define __ASM_AVR32_KDEBUG_H
>>
>> +static inline void arch_breakpoint(void)
>> +{
>> +}
>
> Will not this just be optimized away? Are you expecting other developers to
> add a no-op assembler instruction into this function body?
>
> <snipp>
> --
> Best regards, Hans-Christian Egtvedt
>

Yes, I am hoping the maintainers of each arch to make a decision about
how they wish to implement this and/or change it.  Totally up to you
guys.  I need it stubbed in all the arches so it passes test robot
builds for watchdog.c.

Jeff