summaryrefslogtreecommitdiff
path: root/arch/x86/kvm/x86.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e0aa4dd53c7f..0cf1082455df 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -890,7 +890,8 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
!load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu)))
return 1;
- if (!(cr0 & X86_CR0_PG) && kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE))
+ if (!(cr0 & X86_CR0_PG) &&
+ (is_64_bit_mode(vcpu) || kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE)))
return 1;
static_call(kvm_x86_set_cr0)(vcpu, cr0);
@@ -7121,7 +7122,13 @@ static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
unsigned short port, void *val, unsigned int count)
{
if (vcpu->arch.pio.count) {
- /* Complete previous iteration. */
+ /*
+ * Complete a previous iteration that required userspace I/O.
+ * Note, @count isn't guaranteed to match pio.count as userspace
+ * can modify ECX before rerunning the vCPU. Ignore any such
+ * shenanigans as KVM doesn't support modifying the rep count,
+ * and the emulator ensures @count doesn't overflow the buffer.
+ */
} else {
int r = __emulator_pio_in(vcpu, size, port, count);
if (!r)
@@ -7130,7 +7137,6 @@ static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
/* Results already available, fall through. */
}
- WARN_ON(count != vcpu->arch.pio.count);
complete_emulator_pio_in(vcpu, val);
return 1;
}