[PATCH hci-8.1 1/1] target/i386/kvm: fix latched INIT lost in kvm_put_vcpu_events() #VSTOR-153069

[PATCH hci-8.1 1/1] target/i386/kvm: fix latched INIT lost in kvm_put_vcpu_events() #VSTOR-153069

[Denis V. Lunev]

From: Denis V. Lunev <den@openvz.org>

CPU_INTERRUPT_INIT is 0x0400, while kvm_vcpu_events.smi.latched_init
is a __u8. The assignment truncates the masked value to 0, so every
KVM_SET_VCPU_EVENTS tells KVM to clear an INIT it has latched for a
vCPU in SMM. smi.pending survives only because CPU_INTERRUPT_SMI is
0x0040; normalize both with !! like the neighbouring fields.

Fixes: fc12d72e1082 ("target-i386: add support for SMBASE MSR and SMIs")
Cc: qemu-stable@nongnu.org
Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 target/i386/kvm/kvm.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 8dc0f134990..6efe0e6b308 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -5124,8 +5124,9 @@ static int kvm_put_vcpu_events(X86CPU *cpu, int level)
             /* As soon as these are moved to the kernel, remove them
              * from cs->interrupt_request.
              */
-            events.smi.pending = cs->interrupt_request & CPU_INTERRUPT_SMI;
-            events.smi.latched_init = cs->interrupt_request & CPU_INTERRUPT_INIT;
+            events.smi.pending = !!(cs->interrupt_request & CPU_INTERRUPT_SMI);
+            events.smi.latched_init =
+                !!(cs->interrupt_request & CPU_INTERRUPT_INIT);
             cs->interrupt_request &= ~(CPU_INTERRUPT_INIT | CPU_INTERRUPT_SMI);
         } else {
             /* Keep these in cs->interrupt_request.  */
-- 
2.53.0

Re: [PATCH hci-8.1 1/1] target/i386/kvm: fix latched INIT lost in kvm_put_vcpu_events() #VSTOR-153069

[no-reply]

> From: Denis V. Lunev <den@openvz.org>
> 
> CPU_INTERRUPT_INIT is 0x0400, while kvm_vcpu_events.smi.latched_init
> is a __u8. The assignment truncates the masked value to 0, so every
> KVM_SET_VCPU_EVENTS tells KVM to clear an INIT it has latched for a
> vCPU in SMM. smi.pending survives only because CPU_INTERRUPT_SMI is
> 0x0040; normalize both with !! like the neighbouring fields.
> 
> Fixes: fc12d72e1082 ("target-i386: add support for SMBASE MSR and SMIs")
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Denis V. Lunev <den@openvz.org>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.vzint.dev/#/patchset/20261103181817.834166-1-den@openvz.org?part=1

Re: [PATCH hci-8.1 1/1] target/i386/kvm: fix latched INIT lost in kvm_put_vcpu_events() #VSTOR-153069

[Denis V. Lunev]

On 11/3/26 19:18, Denis V. Lunev wrote:
> From: Denis V. Lunev <den@openvz.org>
>
> CPU_INTERRUPT_INIT is 0x0400, while kvm_vcpu_events.smi.latched_init
> is a __u8. The assignment truncates the masked value to 0, so every
> KVM_SET_VCPU_EVENTS tells KVM to clear an INIT it has latched for a
> vCPU in SMM. smi.pending survives only because CPU_INTERRUPT_SMI is
> 0x0040; normalize both with !! like the neighbouring fields.
>
> Fixes: fc12d72e1082 ("target-i386: add support for SMBASE MSR and SMIs")
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> ---
>  target/i386/kvm/kvm.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
> index 8dc0f134990..6efe0e6b308 100644
> --- a/target/i386/kvm/kvm.c
> +++ b/target/i386/kvm/kvm.c
> @@ -5124,8 +5124,9 @@ static int kvm_put_vcpu_events(X86CPU *cpu, int level)
>              /* As soon as these are moved to the kernel, remove them
>               * from cs->interrupt_request.
>               */
> -            events.smi.pending = cs->interrupt_request & CPU_INTERRUPT_SMI;
> -            events.smi.latched_init = cs->interrupt_request & CPU_INTERRUPT_INIT;
> +            events.smi.pending = !!(cs->interrupt_request & CPU_INTERRUPT_SMI);
> +            events.smi.latched_init =
> +                !!(cs->interrupt_request & CPU_INTERRUPT_INIT);
>              cs->interrupt_request &= ~(CPU_INTERRUPT_INIT | CPU_INTERRUPT_SMI);
>          } else {
>              /* Keep these in cs->interrupt_request.  */
queued mainstream by Paolo

Re: [PATCH hci-8.1 1/1] target/i386/kvm: fix latched INIT lost in kvm_put_vcpu_events() #VSTOR-153069

[Andrey Drobyshev]

On 11/3/26 8:18 PM, Denis V. Lunev wrote:
> From: Denis V. Lunev <den@openvz.org>
> 
> CPU_INTERRUPT_INIT is 0x0400, while kvm_vcpu_events.smi.latched_init
> is a __u8. The assignment truncates the masked value to 0, so every
> KVM_SET_VCPU_EVENTS tells KVM to clear an INIT it has latched for a
> vCPU in SMM. smi.pending survives only because CPU_INTERRUPT_SMI is
> 0x0040; normalize both with !! like the neighbouring fields.
> 
> Fixes: fc12d72e1082 ("target-i386: add support for SMBASE MSR and SMIs")
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> ---
>  target/i386/kvm/kvm.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
> index 8dc0f134990..6efe0e6b308 100644
> --- a/target/i386/kvm/kvm.c
> +++ b/target/i386/kvm/kvm.c
> @@ -5124,8 +5124,9 @@ static int kvm_put_vcpu_events(X86CPU *cpu, int level)
>              /* As soon as these are moved to the kernel, remove them
>               * from cs->interrupt_request.
>               */
> -            events.smi.pending = cs->interrupt_request & CPU_INTERRUPT_SMI;
> -            events.smi.latched_init = cs->interrupt_request & CPU_INTERRUPT_INIT;
> +            events.smi.pending = !!(cs->interrupt_request & CPU_INTERRUPT_SMI);
> +            events.smi.latched_init =
> +                !!(cs->interrupt_request & CPU_INTERRUPT_INIT);
>              cs->interrupt_request &= ~(CPU_INTERRUPT_INIT | CPU_INTERRUPT_SMI);
>          } else {
>              /* Keep these in cs->interrupt_request.  */

Ack
Applied to hci-dev