| Message ID | e974660207b99b822309c09365bf953080131791.1507131424.git.jpoimboe@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/10/2017 17:39, Josh Poimboeuf wrote: > When compiling the kernel with the '-frecord-gcc-switches' flag, objtool > complains: > > arch/x86/kvm/emulate.o: warning: objtool: .GCC.command.line+0x0: special: can't find new instruction > > And also the kernel fails to link. > > The problem is that the 'kvm_fastop_exception' code gets placed into the > throwaway '.GCC.command.line' section instead of '.text'. > > Exception fixup code is conventionally placed in the '.fixup' section, > so put it there where it belongs. > > Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> > Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> > --- > arch/x86/kvm/emulate.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > index a36254cbf776..d90cdc77e077 100644 > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -425,8 +425,10 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); > #op " %al \n\t" \ > FOP_RET > > -asm(".global kvm_fastop_exception \n" > - "kvm_fastop_exception: xor %esi, %esi; ret"); > +asm(".pushsection .fixup, \"ax\"\n" > + ".global kvm_fastop_exception \n" > + "kvm_fastop_exception: xor %esi, %esi; ret\n" > + ".popsection"); > > FOP_START(setcc) > FOP_SETCC(seto) > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a36254cbf776..d90cdc77e077 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -425,8 +425,10 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)); #op " %al \n\t" \ FOP_RET -asm(".global kvm_fastop_exception \n" - "kvm_fastop_exception: xor %esi, %esi; ret"); +asm(".pushsection .fixup, \"ax\"\n" + ".global kvm_fastop_exception \n" + "kvm_fastop_exception: xor %esi, %esi; ret\n" + ".popsection"); FOP_START(setcc) FOP_SETCC(seto)
When compiling the kernel with the '-frecord-gcc-switches' flag, objtool complains: arch/x86/kvm/emulate.o: warning: objtool: .GCC.command.line+0x0: special: can't find new instruction And also the kernel fails to link. The problem is that the 'kvm_fastop_exception' code gets placed into the throwaway '.GCC.command.line' section instead of '.text'. Exception fixup code is conventionally placed in the '.fixup' section, so put it there where it belongs. Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> --- arch/x86/kvm/emulate.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)