[PATCH] Add more prevent_tail_call()
Those also break userland regs like following. 00000000 <sys_chown16>: 0: 0f b7 44 24 0c movzwl 0xc(%esp),%eax 5: 83 ca ff or $0xffffffff,%edx 8: 0f b7 4c 24 08 movzwl 0x8(%esp),%ecx d: 66 83 f8 ff cmp $0xffffffff,%ax 11: 0f 44 c2 cmove %edx,%eax 14: 66 83 f9 ff cmp $0xffffffff,%cx 18: 0f 45 d1 cmovne %ecx,%edx 1b: 89 44 24 0c mov %eax,0xc(%esp) 1f: 89 54 24 08 mov %edx,0x8(%esp) 23: e9 fc ff ff ff jmp 24 <sys_chown16+0x24> where the tailcall at the end overwrites the incoming stack-frame. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> [ I would _really_ like to have a way to tell gcc about calling conventions. The "prevent_tail_call()" macro is pretty ugly ] Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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