* [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios
@ 2007-01-31 15:00 Avi Kivity
2007-01-31 15:02 ` Avi Kivity
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Avi Kivity @ 2007-01-31 15:00 UTC (permalink / raw)
To: kvm-devel; +Cc: linux-kernel, akpm, mingo
Intel hosts, without long mode, and with nx support disabled in the bios
have an efer that is readable but not writable. This causes a lockup on
switch to guest mode (even though it should exit with reason 34 according to
the documentation).
Signed-off-by: Avi Kivity <avi@qumranet.com>
Index: linux-2.6/drivers/kvm/vmx.c
===================================================================
--- linux-2.6.orig/drivers/kvm/vmx.c
+++ linux-2.6/drivers/kvm/vmx.c
@@ -1128,6 +1128,8 @@ static int vmx_vcpu_setup(struct kvm_vcp
if (rdmsr_safe(index, &data_low, &data_high) < 0)
continue;
+ if (wrmsr_safe(index, data_low, data_high) < 0)
+ continue;
data = data_low | ((u64)data_high << 32);
vcpu->host_msrs[j].index = index;
vcpu->host_msrs[j].reserved = 0;
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios
2007-01-31 15:00 [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios Avi Kivity
@ 2007-01-31 15:02 ` Avi Kivity
2007-02-01 2:52 ` [kvm-devel] " Jeff Chua
2007-02-01 7:55 ` Ingo Molnar
2 siblings, 0 replies; 4+ messages in thread
From: Avi Kivity @ 2007-01-31 15:02 UTC (permalink / raw)
To: akpm; +Cc: kvm-devel, linux-kernel, mingo
Avi Kivity wrote:
> Intel hosts, without long mode, and with nx support disabled in the bios
> have an efer that is readable but not writable. This causes a lockup on
> switch to guest mode (even though it should exit with reason 34 according to
> the documentation).
>
>
Andrew, I believe this is 2.6.20 material.
> Signed-off-by: Avi Kivity <avi@qumranet.com>
>
> Index: linux-2.6/drivers/kvm/vmx.c
> ===================================================================
> --- linux-2.6.orig/drivers/kvm/vmx.c
> +++ linux-2.6/drivers/kvm/vmx.c
> @@ -1128,6 +1128,8 @@ static int vmx_vcpu_setup(struct kvm_vcp
>
> if (rdmsr_safe(index, &data_low, &data_high) < 0)
> continue;
> + if (wrmsr_safe(index, data_low, data_high) < 0)
> + continue;
> data = data_low | ((u64)data_high << 32);
> vcpu->host_msrs[j].index = index;
> vcpu->host_msrs[j].reserved = 0;
>
--
error compiling committee.c: too many arguments to function
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [kvm-devel] [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios
2007-01-31 15:00 [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios Avi Kivity
2007-01-31 15:02 ` Avi Kivity
@ 2007-02-01 2:52 ` Jeff Chua
2007-02-01 7:55 ` Ingo Molnar
2 siblings, 0 replies; 4+ messages in thread
From: Jeff Chua @ 2007-02-01 2:52 UTC (permalink / raw)
To: Avi Kivity; +Cc: kvm-devel, akpm, linux-kernel
On 1/31/07, Avi Kivity <avi@qumranet.com> wrote:
> Intel hosts, without long mode, and with nx support disabled in the bios
> have an efer that is readable but not writable. This causes a lockup on
> switch to guest mode (even though it should exit with reason 34 according to
> the documentation).
Avi, thank you for the patch. I can confirm that this patch works on
my IBM X60s notebook. Without it, the whole PC locks up upon starting
qemu.
Thanks,
Jeff.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios
2007-01-31 15:00 [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios Avi Kivity
2007-01-31 15:02 ` Avi Kivity
2007-02-01 2:52 ` [kvm-devel] " Jeff Chua
@ 2007-02-01 7:55 ` Ingo Molnar
2 siblings, 0 replies; 4+ messages in thread
From: Ingo Molnar @ 2007-02-01 7:55 UTC (permalink / raw)
To: Avi Kivity; +Cc: kvm-devel, linux-kernel, akpm
* Avi Kivity <avi@qumranet.com> wrote:
> Intel hosts, without long mode, and with nx support disabled in the
> bios have an efer that is readable but not writable. This causes a
> lockup on switch to guest mode (even though it should exit with reason
> 34 according to the documentation).
>
> Signed-off-by: Avi Kivity <avi@qumranet.com>
i think this is for v2.6.20. I have tested this ontop of -rc7.
Acked-by: Ingo Molnar <mingo@elte.hu>
Ingo
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2007-02-01 7:56 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2007-01-31 15:00 [PATCH] KVM: Fix lockup on 32-bit intel hosts with nx disabled in the bios Avi Kivity
2007-01-31 15:02 ` Avi Kivity
2007-02-01 2:52 ` [kvm-devel] " Jeff Chua
2007-02-01 7:55 ` Ingo Molnar
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox