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Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
-rw-r--r--arch/x86/kvm/vmx/vmx.c47
1 files changed, 38 insertions, 9 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 4ac676066d60..aca3ae2a02f3 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1487,11 +1487,12 @@ static int vmx_rtit_ctl_check(struct kvm_vcpu *vcpu, u64 data)
return 0;
}
-static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, void *insn, int insn_len)
+static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
+ void *insn, int insn_len)
{
/*
* Emulation of instructions in SGX enclaves is impossible as RIP does
- * not point tthe failing instruction, and even if it did, the code
+ * not point at the failing instruction, and even if it did, the code
* stream is inaccessible. Inject #UD instead of exiting to userspace
* so that guest userspace can't DoS the guest simply by triggering
* emulation (enclaves are CPL3 only).
@@ -2603,7 +2604,6 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
return -EIO;
vmcs_conf->size = vmx_msr_high & 0x1fff;
- vmcs_conf->order = get_order(vmcs_conf->size);
vmcs_conf->basic_cap = vmx_msr_high & ~0x1fff;
vmcs_conf->revision_id = vmx_msr_low;
@@ -2628,7 +2628,7 @@ struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags)
struct page *pages;
struct vmcs *vmcs;
- pages = __alloc_pages_node(node, flags, vmcs_config.order);
+ pages = __alloc_pages_node(node, flags, 0);
if (!pages)
return NULL;
vmcs = page_address(pages);
@@ -2647,7 +2647,7 @@ struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags)
void free_vmcs(struct vmcs *vmcs)
{
- free_pages((unsigned long)vmcs, vmcs_config.order);
+ free_page((unsigned long)vmcs);
}
/*
@@ -4094,10 +4094,14 @@ void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
vmcs_write32(HOST_IA32_SYSENTER_CS, low32);
/*
- * If 32-bit syscall is enabled, vmx_vcpu_load_vcms rewrites
- * HOST_IA32_SYSENTER_ESP.
+ * SYSENTER is used for 32-bit system calls on either 32-bit or
+ * 64-bit kernels. It is always zero If neither is allowed, otherwise
+ * vmx_vcpu_load_vmcs loads it with the per-CPU entry stack (and may
+ * have already done so!).
*/
- vmcs_writel(HOST_IA32_SYSENTER_ESP, 0);
+ if (!IS_ENABLED(CONFIG_IA32_EMULATION) && !IS_ENABLED(CONFIG_X86_32))
+ vmcs_writel(HOST_IA32_SYSENTER_ESP, 0);
+
rdmsrl(MSR_IA32_SYSENTER_EIP, tmpl);
vmcs_writel(HOST_IA32_SYSENTER_EIP, tmpl); /* 22.2.3 */
@@ -4901,8 +4905,33 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
dr6 = vmx_get_exit_qual(vcpu);
if (!(vcpu->guest_debug &
(KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))) {
+ /*
+ * If the #DB was due to ICEBP, a.k.a. INT1, skip the
+ * instruction. ICEBP generates a trap-like #DB, but
+ * despite its interception control being tied to #DB,
+ * is an instruction intercept, i.e. the VM-Exit occurs
+ * on the ICEBP itself. Note, skipping ICEBP also
+ * clears STI and MOVSS blocking.
+ *
+ * For all other #DBs, set vmcs.PENDING_DBG_EXCEPTIONS.BS
+ * if single-step is enabled in RFLAGS and STI or MOVSS
+ * blocking is active, as the CPU doesn't set the bit
+ * on VM-Exit due to #DB interception. VM-Entry has a
+ * consistency check that a single-step #DB is pending
+ * in this scenario as the previous instruction cannot
+ * have toggled RFLAGS.TF 0=>1 (because STI and POP/MOV
+ * don't modify RFLAGS), therefore the one instruction
+ * delay when activating single-step breakpoints must
+ * have already expired. Note, the CPU sets/clears BS
+ * as appropriate for all other VM-Exits types.
+ */
if (is_icebp(intr_info))
WARN_ON(!skip_emulated_instruction(vcpu));
+ else if ((vmx_get_rflags(vcpu) & X86_EFLAGS_TF) &&
+ (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
+ (GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS)))
+ vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS,
+ vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS) | DR6_BS);
kvm_queue_exception_p(vcpu, DB_VECTOR, dr6);
return 1;
@@ -5397,7 +5426,7 @@ static int handle_ept_misconfig(struct kvm_vcpu *vcpu)
{
gpa_t gpa;
- if (!vmx_can_emulate_instruction(vcpu, NULL, 0))
+ if (!vmx_can_emulate_instruction(vcpu, EMULTYPE_PF, NULL, 0))
return 1;
/*