| Message ID | 5800C37F02000078001174F3@prv-mh.provo.novell.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 14/10/16 10:37, Jan Beulich wrote: > The high halves of all GPRs are undefined in 32-bit and compat modes, > and the dependency is being obfuscated by our structure field names not > matching architectural register names (it was actually while putting > together a patch to correct this when I noticed the issue here). > > For consistency also use the architecturally correct names on the > output side. > > Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
> -----Original Message----- > From: Jan Beulich [mailto:JBeulich@suse.com] > Sent: 14 October 2016 05:38 > To: xen-devel <xen-devel@lists.xenproject.org> > Cc: Paul Durrant <Paul.Durrant@citrix.com> > Subject: [PATCH] x86/Viridian: don't depend on undefined register state > > The high halves of all GPRs are undefined in 32-bit and compat modes, > and the dependency is being obfuscated by our structure field names not > matching architectural register names (it was actually while putting > together a patch to correct this when I noticed the issue here). > > For consistency also use the architecturally correct names on the > output side. > > Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> > > --- a/xen/arch/x86/hvm/viridian.c > +++ b/xen/arch/x86/hvm/viridian.c > @@ -667,9 +667,9 @@ int viridian_hypercall(struct cpu_user_r > output_params_gpa = regs->r8; > break; > case 4: > - input.raw = ((uint64_t)regs->edx << 32) | regs->eax; > - input_params_gpa = ((uint64_t)regs->ebx << 32) | regs->ecx; > - output_params_gpa = ((uint64_t)regs->edi << 32) | regs->esi; > + input.raw = (regs->rdx << 32) | regs->_eax; > + input_params_gpa = (regs->rbx << 32) | regs->_ecx; > + output_params_gpa = (regs->rdi << 32) | regs->_esi; > break; > default: > goto out; > @@ -770,8 +770,8 @@ out: > regs->rax = output.raw; > break; > default: > - regs->edx = output.raw >> 32; > - regs->eax = output.raw; > + regs->rdx = output.raw >> 32; > + regs->rax = (uint32_t)output.raw; > break; > } > > >
--- a/xen/arch/x86/hvm/viridian.c +++ b/xen/arch/x86/hvm/viridian.c @@ -667,9 +667,9 @@ int viridian_hypercall(struct cpu_user_r output_params_gpa = regs->r8; break; case 4: - input.raw = ((uint64_t)regs->edx << 32) | regs->eax; - input_params_gpa = ((uint64_t)regs->ebx << 32) | regs->ecx; - output_params_gpa = ((uint64_t)regs->edi << 32) | regs->esi; + input.raw = (regs->rdx << 32) | regs->_eax; + input_params_gpa = (regs->rbx << 32) | regs->_ecx; + output_params_gpa = (regs->rdi << 32) | regs->_esi; break; default: goto out; @@ -770,8 +770,8 @@ out: regs->rax = output.raw; break; default: - regs->edx = output.raw >> 32; - regs->eax = output.raw; + regs->rdx = output.raw >> 32; + regs->rax = (uint32_t)output.raw; break; }