[PATCH] vmx: Fix register constraint in launch code
authorHerbert Xu <herbert@gondor.apana.org.au>
Tue, 23 Jan 2007 03:10:00 +0000 (14:10 +1100)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Tue, 23 Jan 2007 03:27:02 +0000 (19:27 -0800)
Both "=r" and "=g" breaks my build on i386:

  $ make
    CC [M]  drivers/kvm/vmx.o
  {standard input}: Assembler messages:
  {standard input}:3318: Error: bad register name `%sil'
  make[1]: *** [drivers/kvm/vmx.o] Error 1
  make: *** [_module_drivers/kvm] Error 2

The reason is that setbe requires an 8-bit register but "=r" does not
constrain the target register to be one that has an 8-bit version on
i386.

According to

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10153

the correct constraint is "=q".

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/kvm/vmx.c

index ce219e3f557fecfbe64aadf71bc6cad1ca17cb1f..0aa2659f6ae573353c013bc83bca985d26e3c9c3 100644 (file)
@@ -1824,7 +1824,7 @@ again:
 #endif
                "setbe %0 \n\t"
                "popf \n\t"
-             : "=g" (fail)
+             : "=q" (fail)
              : "r"(vcpu->launched), "d"((unsigned long)HOST_RSP),
                "c"(vcpu),
                [rax]"i"(offsetof(struct kvm_vcpu, regs[VCPU_REGS_RAX])),