Jan Beulich
2013-Nov-13 17:09 UTC
[PATCH] x86/HVM: 32-bit IN result must be zero-extended to 64 bits (part 2)
Just spotted a counterpart of what commit 9d89100b (same title) dealt
with.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- 2013-10-16.orig/xen/arch/x86/hvm/io.c 2013-11-13 17:45:16.000000000 +0100
+++ 2013-10-16/xen/arch/x86/hvm/io.c 2013-11-13 17:47:47.000000000 +0100
@@ -290,8 +290,10 @@ void hvm_io_assist(void)
(void)handle_mmio();
break;
case HVMIO_handle_pio_awaiting_completion:
- memcpy(&guest_cpu_user_regs()->eax,
- &p->data, vio->io_size);
+ if ( vio->io_size == 4 ) /* Needs zero extension. */
+ guest_cpu_user_regs()->rax = (uint32_t)p->data;
+ else
+ memcpy(&guest_cpu_user_regs()->rax, &p->data,
vio->io_size);
break;
default:
break;
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Andrew Cooper
2013-Nov-13 17:12 UTC
Re: [PATCH] x86/HVM: 32-bit IN result must be zero-extended to 64 bits (part 2)
On 13/11/13 17:09, Jan Beulich wrote:> Just spotted a counterpart of what commit 9d89100b (same title) dealt > with. > > Signed-off-by: Jan Beulich <jbeulich@suse.com>Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>> > --- 2013-10-16.orig/xen/arch/x86/hvm/io.c 2013-11-13 17:45:16.000000000 +0100 > +++ 2013-10-16/xen/arch/x86/hvm/io.c 2013-11-13 17:47:47.000000000 +0100 > @@ -290,8 +290,10 @@ void hvm_io_assist(void) > (void)handle_mmio(); > break; > case HVMIO_handle_pio_awaiting_completion: > - memcpy(&guest_cpu_user_regs()->eax, > - &p->data, vio->io_size); > + if ( vio->io_size == 4 ) /* Needs zero extension. */ > + guest_cpu_user_regs()->rax = (uint32_t)p->data; > + else > + memcpy(&guest_cpu_user_regs()->rax, &p->data, vio->io_size); > break; > default: > break; > > > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Keir Fraser
2013-Nov-13 18:09 UTC
Re: [PATCH] x86/HVM: 32-bit IN result must be zero-extended to 64 bits (part 2)
On 13/11/2013 17:09, "Jan Beulich" <JBeulich@suse.com> wrote:> Just spotted a counterpart of what commit 9d89100b (same title) dealt > with. > > Signed-off-by: Jan Beulich <jbeulich@suse.com>Acked-by: Keir Fraser <keir@xen.org>> --- 2013-10-16.orig/xen/arch/x86/hvm/io.c 2013-11-13 17:45:16.000000000 +0100 > +++ 2013-10-16/xen/arch/x86/hvm/io.c 2013-11-13 17:47:47.000000000 +0100 > @@ -290,8 +290,10 @@ void hvm_io_assist(void) > (void)handle_mmio(); > break; > case HVMIO_handle_pio_awaiting_completion: > - memcpy(&guest_cpu_user_regs()->eax, > - &p->data, vio->io_size); > + if ( vio->io_size == 4 ) /* Needs zero extension. */ > + guest_cpu_user_regs()->rax = (uint32_t)p->data; > + else > + memcpy(&guest_cpu_user_regs()->rax, &p->data, vio->io_size); > break; > default: > break; > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel