diff options
authorVitaly Kuznetsov <>2020-09-08 15:53:50 +0200
committerPaolo Bonzini <>2020-09-12 02:22:21 -0400
commitcc17b22559d9b9c8b7540810df172f3d7af901ce (patch)
parent244081f9073fe934adbcb2db6496b91b8fc51655 (diff)
x86/kvm: don't forget to ACK async PF IRQ
Merge commit 26d05b368a5c0 ("Merge branch 'kvm-async-pf-int' into HEAD") tried to adapt the new interrupt based async PF mechanism to the newly introduced IDTENTRY magic but unfortunately it missed the fact that DEFINE_IDTENTRY_SYSVEC() doesn't call ack_APIC_irq() on its own and all DEFINE_IDTENTRY_SYSVEC() users have to call it manually. As the result all multi-CPU KVM guest hang on boot when KVM_FEATURE_ASYNC_PF_INT is present. The breakage went unnoticed because no KVM userspace (e.g. QEMU) currently set it (and thus async PF mechanism is currently disabled) but we're about to change that. Fixes: 26d05b368a5c0 ("Merge branch 'kvm-async-pf-int' into HEAD") Signed-off-by: Vitaly Kuznetsov <> Message-Id: <> Tested-by: Ingo Molnar <> Signed-off-by: Paolo Bonzini <>
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 02d15485ff1d..1b51b727b140 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -271,6 +271,8 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_kvm_asyncpf_interrupt)
struct pt_regs *old_regs = set_irq_regs(regs);
u32 token;
+ ack_APIC_irq();
if (__this_cpu_read(apf_reason.enabled)) {