Re: [PATCH v2 0/3] locking/rwsem/x86: Add stack frame dependency for some inline asm

From	Josh Poimboeuf <jpoimboe@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2 0/3] locking/rwsem/x86: Add stack frame dependency for some inline asm
Date	2017-09-07 01:10 +0200
Message-ID	<umRCh-8qR-3@gated-at.bofh.it> (permalink)
References	<umB4t-5b7-3@gated-at.bofh.it> <umRiV-85i-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Wed, Sep 06, 2017 at 05:44:58PM -0500, Miguel Bernal Marin wrote:
> Some warning were showed by objtool using gcc 7.2.0
> 
> kernel/locking/rwsem.o: warning: objtool: up_read()+0x11: call without frame pointer save/setup
> kernel/locking/rwsem.o: warning: objtool: up_write()+0x17: call without frame pointer save/setup
> kernel/locking/rwsem.o: warning: objtool: downgrade_write()+0x22: call without frame pointer save/setup
> 
> which means gcc placed an inline asm function and its call instruction before
> the frame pointer setup.
>  
> This series forces a stack frame to be created before the call instruction
> by listing the stack pointer as an output operand in the inline asm statement.
> 
> Changes in v2:
>   - Update first parameter from _ASM_ADD to '%3' at __downgrade_write()
> 
> Miguel Bernal Marin (3):
>   locking/rwsem/x86: Add stack frame dependency for __up_read()
>   locking/rwsem/x86: Add stack frame dependency for __up_write()
>   locking/rwsem/x86: Add stack frame dependency for __downgrade_write()
> 
>  arch/x86/include/asm/rwsem.h | 18 ++++++++++++------
>  1 file changed, 12 insertions(+), 6 deletions(-)

For the series:

Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>

-- 
Josh

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[PATCH 0/3] locking/rwsem/x86: Add stack frame dependency for some inline asm Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com> - 2017-09-06 07:30 +0200
  [PATCH v2 0/3] locking/rwsem/x86: Add stack frame dependency for some inline asm Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com> - 2017-09-07 00:50 +0200
    [PATCH v2 1/3] locking/rwsem/x86: Add stack frame dependency for __up_read() Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com> - 2017-09-07 00:50 +0200
      Re: [PATCH v2 1/3] locking/rwsem/x86: Add stack frame dependency for  __up_read() Ingo Molnar <mingo@kernel.org> - 2017-09-07 09:20 +0200
    [PATCH v2 3/3] locking/rwsem/x86: Add stack frame dependency for __downgrade_write() Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com> - 2017-09-07 00:50 +0200
    [PATCH v2 2/3] locking/rwsem/x86: Add stack frame dependency for __up_write() Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com> - 2017-09-07 00:50 +0200
    Re: [PATCH v2 0/3] locking/rwsem/x86: Add stack frame dependency for  some inline asm Josh Poimboeuf <jpoimboe@redhat.com> - 2017-09-07 01:10 +0200

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