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