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Subject[PATCH v3 0/6] locking/rwsem/x86: Add stack frame dependency for some inline asm
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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.

Also to be easy to maintain and understand the operands from the extended
assembler instructions were converted to named operands.

Changes in v3:
- Convert to named operands

Changes in v2:
- Update first parameter from _ASM_ADD to '%3' at __downgrade_write()


Miguel Bernal Marin (6):
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()
x86, asm/rwsem: Use named operands in __up_read()
x86, asm/rwsem: Use named operands in __up_write()
x86, asm/rwsem: Use named operands in __downgrade_write()

arch/x86/include/asm/rwsem.h | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)

--
2.14.1

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