lkml.org 
[lkml]   [2020]   [May]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 16/28] KVM: nSVM: restore clobbered INT_CTL fields after clearing VINTR
Date
Restore the INT_CTL value from the guest's VMCB once we've stopped using
it, so that virtual interrupts can be injected as requested by L1.
V_TPR is up-to-date however, and it can change if the guest writes to CR8,
so keep it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/svm/svm.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 77d3f441cd87..c213011a82e3 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1365,9 +1365,17 @@ static void svm_set_vintr(struct vcpu_svm *svm)

static void svm_clear_vintr(struct vcpu_svm *svm)
{
+ const u32 mask = V_TPR_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK | V_INTR_MASKING_MASK;
clr_intercept(svm, INTERCEPT_VINTR);

- svm->vmcb->control.int_ctl &= ~V_IRQ_MASK;
+ /* Drop int_ctl fields related to VINTR injection. */
+ svm->vmcb->control.int_ctl &= mask;
+ if (is_guest_mode(&svm->vcpu)) {
+ WARN_ON((svm->vmcb->control.int_ctl & V_TPR_MASK) !=
+ (svm->nested.ctl.int_ctl & V_TPR_MASK));
+ svm->vmcb->control.int_ctl |= svm->nested.ctl.int_ctl & ~mask;
+ }
+
mark_dirty(svm->vmcb, VMCB_INTR);
}

--
2.26.2

\
 
 \ /
  Last update: 2020-05-26 19:24    [W:0.141 / U:1.468 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site