[PATCH] kvm: vmx: Fix entry nubmer check for add_atomic_switch_msr()

From: Xiaoyao Li
Date: Wed Feb 13 2019 - 23:12:03 EST


Commit ca83b4a7f2d068da79a0 ("x86/KVM/VMX: Add find_msr() helper function")
introduces the helper function find_msr(), which returns -ENOENT when
not find the msr in vmx->msr_autoload.guest/host. Correct checking contion
of no more available entry in vmx->msr_autoload.

Fixes: ca83b4a7f2d0 ("x86/KVM/VMX: Add find_msr() helper function")
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxxxxxxxx>
---
arch/x86/kvm/vmx/vmx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 95d618045001..1aaef2d536bd 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -863,7 +863,8 @@ static void add_atomic_switch_msr(struct vcpu_vmx *vmx, unsigned msr,
if (!entry_only)
j = find_msr(&m->host, msr);

- if (i == NR_AUTOLOAD_MSRS || j == NR_AUTOLOAD_MSRS) {
+ if ((i < 0 && m->guest.nr == NR_AUTOLOAD_MSRS) ||
+ (j < 0 && m->host.nr == NR_AUTOLOAD_MSRS)) {
printk_once(KERN_WARNING "Not enough msr switch entries. "
"Can't add msr %x\n", msr);
return;
--
2.19.1