Re: [Xen-devel] [PATCH for-4.13 v3 2/2] x86/vmx: always sync PIR to IRR before vmentry

[Joe Jin <joe.jin@xxxxxxxxxx>]

On 11/26/19 5:26 AM, Roger Pau Monne wrote:
> When using posted interrupts on Intel hardware it's possible that the
> vCPU resumes execution with a stale local APIC IRR register because
> depending on the interrupts to be injected vlapic_has_pending_irq
> might not be called, and thus PIR won't be synced into IRR.
> 
> Fix this by making sure PIR is always synced to IRR in
> hvm_vcpu_has_pending_irq regardless of what interrupts are pending.
> 
> While there also simplify the code in __vmx_deliver_posted_interrupt:
> only raise a softirq if the vCPU is the one currently running and
> __vmx_deliver_posted_interrupt is called from interrupt context. The
> softirq is raised to make sure vmx_intr_assist is retried if the
> interrupt happens to arrive after vmx_intr_assist but before
> interrupts are disabled in vmx_do_vmentry. Also simplify the logic for
> IPIing other pCPUs, there's no need to check v->processor since the
> IPI should be sent as long as the vCPU is not the current one and it's
> running.
> 
> Reported-by: Joe Jin <joe.jin@xxxxxxxxxx>
> Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> ---
> Cc: Juergen Gross <jgross@xxxxxxxx>

Patch works for me.
Tested-by: Joe Jin <joe.jin@xxxxxxxxxx>

Thanks,
Joe

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel