On Tue, Sep 10, 2013 at 01:05:21PM +0200, Paolo Bonzini wrote: > Il 04/09/2013 18:44, Paul Gortmaker ha scritto: > > Hi Greg, > > > > The 3.4.44+ cherry pick: > > > > ---------------- > > commit 5b5b30580218eae22609989546bac6e44d0eda6e > > Author: Gleb Natapov <gleb@xxxxxxxxxx> > > Date: Wed Apr 24 13:38:36 2013 +0300 > > > > KVM: X86 emulator: fix source operand decoding for 8bit mov[zs]x instructions > > > > commit 660696d1d16a71e15549ce1bf74953be1592bcd3 upstream. > > > > Source operand for one byte mov[zs]x is decoded incorrectly if it is in > > high byte register. Fix that. > > > > Signed-off-by: Gleb Natapov <gleb@xxxxxxxxxx> > > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > ---------------- > > > > introduces the following: > > > > arch/x86/kvm/emulate.c: In function ‘decode_operand’: > > arch/x86/kvm/emulate.c:3974:4: warning: passing argument 1 of ‘decode_register’ makes integer from pointer without a cast [enabled by default] > > arch/x86/kvm/emulate.c:789:14: note: expected ‘u8’ but argument is of type ‘struct x86_emulate_ctxt *’ > > arch/x86/kvm/emulate.c:3974:4: warning: passing argument 2 of ‘decode_register’ makes pointer from integer without a cast [enabled by default] > > arch/x86/kvm/emulate.c:789:14: note: expected ‘long unsigned int *’ but argument is of type ‘u8’ > > > > Based on the severity of the warnings above, I'm reasonably sure there will > > be some kind of runtime regressions due to this, but I stopped to investigate > > the warnings as soon as I saw them, before any run time testing. > > > > It happens because mainline v3.7-rc1~113^2~40 (dd856efafe60) does this: > > > > -static void *decode_register(u8 modrm_reg, unsigned long *regs, > > +static void *decode_register(struct x86_emulate_ctxt *ctxt, u8 modrm_reg, > > > > Since 660696d1d16a71e1 was only applied to stable 3.4, 3.8, and 3.9 -- and > > the prerequisite above is in 3.7+, the issue should be limited to 3.4.44+ > > Right, the fix is not important to have for 3.4 kernels. Thanks for letting me know, I've now reverted it. greg k-h -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
