From e4481000ac689119ed042caf499bd86b69f14642 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 7 Jun 2022 17:00:53 +0200 Subject: [PATCH] x86: drop bogus "cc" clobber from __try_cmpxchg_user_asm() commit 1df931d95f4dc1c11db1123e85d4e08156e46ef9 upstream. As noted (and fixed) a couple of times in the past, "=@cc" outputs and clobbering of "cc" don't work well together. The compiler appears to mean to reject such, but doesn't - in its upstream form - quite manage to yet for "cc". Furthermore two similar macros don't clobber "cc", and clobbering "cc" is pointless in asm()-s for x86 anyway - the compiler always assumes status flags to be clobbered there. Fixes: 989b5db215a2 ("x86/uaccess: Implement macros for CMPXCHG on user addresses") Signed-off-by: Jan Beulich Message-Id: <485c0c0b-a3a7-0b7c-5264-7d00c01de032@suse.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/uaccess.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 2f4c9c1..ab5e577 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -471,7 +471,7 @@ do { \ [ptr] "+m" (*_ptr), \ [old] "+a" (__old) \ : [new] ltype (__new) \ - : "memory", "cc"); \ + : "memory"); \ if (unlikely(__err)) \ goto label; \ if (unlikely(!success)) \ -- 2.7.4