Re: [PATCH 3/3] locking/rwsem/x86: Add stack frame dependency for __downgrade_write()

2017-09-07 Thread Peter Zijlstra
On Wed, Sep 06, 2017 at 04:33:02PM -0500, Josh Poimboeuf wrote: > On Wed, Sep 06, 2017 at 12:26:13AM -0500, Miguel Bernal Marin wrote: > > kernel/locking/rwsem.o: warning: objtool: downgrade_write()+0x22: call > > without frame pointer save/setup > > > > The warning means gcc 7.2.0 placed the __d

Re: [PATCH 3/3] locking/rwsem/x86: Add stack frame dependency for __downgrade_write()

2017-09-06 Thread Miguel Bernal Marin
On Wed, Sep 06, 2017 at 04:33:02PM -0500, Josh Poimboeuf wrote: > On Wed, Sep 06, 2017 at 12:26:13AM -0500, Miguel Bernal Marin wrote: > > kernel/locking/rwsem.o: warning: objtool: downgrade_write()+0x22: call > > without frame pointer save/setup > > > > The warning means gcc 7.2.0 placed the __d

Re: [PATCH 3/3] locking/rwsem/x86: Add stack frame dependency for __downgrade_write()

2017-09-06 Thread Josh Poimboeuf
On Wed, Sep 06, 2017 at 12:26:13AM -0500, Miguel Bernal Marin wrote: > kernel/locking/rwsem.o: warning: objtool: downgrade_write()+0x22: call > without frame pointer save/setup > > The warning means gcc 7.2.0 placed the __downgrade_write() inline asm (and > its call instruction) before the frame

[PATCH 3/3] locking/rwsem/x86: Add stack frame dependency for __downgrade_write()

2017-09-05 Thread Miguel Bernal Marin
kernel/locking/rwsem.o: warning: objtool: downgrade_write()+0x22: call without frame pointer save/setup The warning means gcc 7.2.0 placed the __downgrade_write() inline asm (and its call instruction) before the frame pointer setup in downgrade_write(), which breaks frame pointer convention and c