Commit 9893deb0 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

Merge tag 'kvm-x86-fixes-6.12-rcN' of https://github.com/kvm-x86/linux into HEAD 

KVM x86 and selftests fixes for 6.12:

 - Increase the timeout for the memslot performance selftest to avoid false
   failures on arm64 and nested x86 platforms.

 - Fix a goof in the guest_memfd selftest where a for-loop initialized a
   bit mask to zero instead of BIT(0).

 - Disable strict aliasing when building KVM selftests to prevent the
   compiler from treating things like "u64 *" to "uint64_t *" cases as
   undefined behavior, which can lead to nasty, hard to debug failures.

 - Force -march=x86-64-v2 for KVM x86 selftests if and only if the uarch
   is supported by the compiler.

 - When emulating a guest TLB flush for a nested guest, flush vpid01, not
   vpid02, if L2 is active but VPID is disabled in vmcs12, i.e. if L2 and
   L1 are sharing VPID '0' (from L1's perspective).

 - Fix a bug in the SNP initialization flow where KVM would return '0' to
   userspace instead of -errno on failure.
parents 59b723cd e5d253c6

arch/x86/kvm/svm/sev.c

+5 −2
Original line number Diff line number Diff line
@@ -450,8 +450,11 @@ static int __sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp, 
		goto e_free;



	/* This needs to happen after SEV/SNP firmware initialization. */

	if (vm_type == KVM_X86_SNP_VM && snp_guest_req_init(kvm))

	if (vm_type == KVM_X86_SNP_VM) {

		ret = snp_guest_req_init(kvm);

		if (ret)

			goto e_free;

	}



	INIT_LIST_HEAD(&sev->regions_list);

	INIT_LIST_HEAD(&sev->mirror_vms);

arch/x86/kvm/vmx/nested.c

+25 −5
Original line number Diff line number Diff line
@@ -1197,11 +1197,14 @@ static void nested_vmx_transition_tlb_flush(struct kvm_vcpu *vcpu, 
	kvm_hv_nested_transtion_tlb_flush(vcpu, enable_ept);



	/*

	 * If vmcs12 doesn't use VPID, L1 expects linear and combined mappings

	 * for *all* contexts to be flushed on VM-Enter/VM-Exit, i.e. it's a

	 * full TLB flush from the guest's perspective.  This is required even

	 * if VPID is disabled in the host as KVM may need to synchronize the

	 * MMU in response to the guest TLB flush.

	 * If VPID is disabled, then guest TLB accesses use VPID=0, i.e. the

	 * same VPID as the host, and so architecturally, linear and combined

	 * mappings for VPID=0 must be flushed at VM-Enter and VM-Exit.  KVM

	 * emulates L2 sharing L1's VPID=0 by using vpid01 while running L2,

	 * and so KVM must also emulate TLB flush of VPID=0, i.e. vpid01.  This

	 * is required if VPID is disabled in KVM, as a TLB flush (there are no

	 * VPIDs) still occurs from L1's perspective, and KVM may need to

	 * synchronize the MMU in response to the guest TLB flush.

	 *

	 * Note, using TLB_FLUSH_GUEST is correct even if nested EPT is in use.

	 * EPT is a special snowflake, as guest-physical mappings aren't
@@ -2315,6 +2318,17 @@ static void prepare_vmcs02_early_rare(struct vcpu_vmx *vmx, 


	vmcs_write64(VMCS_LINK_POINTER, INVALID_GPA);



	/*

	 * If VPID is disabled, then guest TLB accesses use VPID=0, i.e. the

	 * same VPID as the host.  Emulate this behavior by using vpid01 for L2

	 * if VPID is disabled in vmcs12.  Note, if VPID is disabled, VM-Enter

	 * and VM-Exit are architecturally required to flush VPID=0, but *only*

	 * VPID=0.  I.e. using vpid02 would be ok (so long as KVM emulates the

	 * required flushes), but doing so would cause KVM to over-flush.  E.g.

	 * if L1 runs L2 X with VPID12=1, then runs L2 Y with VPID12 disabled,

	 * and then runs L2 X again, then KVM can and should retain TLB entries

	 * for VPID12=1.

	 */

	if (enable_vpid) {

		if (nested_cpu_has_vpid(vmcs12) && vmx->nested.vpid02)

			vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->nested.vpid02);
@@ -5950,6 +5964,12 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) 
		return nested_vmx_fail(vcpu,

			VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);



	/*

	 * Always flush the effective vpid02, i.e. never flush the current VPID

	 * and never explicitly flush vpid01.  INVVPID targets a VPID, not a

	 * VMCS, and so whether or not the current vmcs12 has VPID enabled is

	 * irrelevant (and there may not be a loaded vmcs12).

	 */

	vpid02 = nested_get_vpid02(vcpu);

	switch (type) {

	case VMX_VPID_EXTENT_INDIVIDUAL_ADDR:

arch/x86/kvm/vmx/vmx.c

+1 −1
Original line number Diff line number Diff line
@@ -3216,7 +3216,7 @@ void vmx_flush_tlb_all(struct kvm_vcpu *vcpu) 


static inline int vmx_get_current_vpid(struct kvm_vcpu *vcpu)

{

	if (is_guest_mode(vcpu))

	if (is_guest_mode(vcpu) && nested_cpu_has_vpid(get_vmcs12(vcpu)))

		return nested_get_vpid02(vcpu);

	return to_vmx(vcpu)->vpid;

}

tools/testing/selftests/kvm/Makefile

+6 −4
Original line number Diff line number Diff line
@@ -241,16 +241,18 @@ CFLAGS += -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99 \ 
	-Wno-gnu-variable-sized-type-not-at-end -MD -MP -DCONFIG_64BIT \

	-fno-builtin-memcmp -fno-builtin-memcpy \

	-fno-builtin-memset -fno-builtin-strnlen \

	-fno-stack-protector -fno-PIE -I$(LINUX_TOOL_INCLUDE) \

	-I$(LINUX_TOOL_ARCH_INCLUDE) -I$(LINUX_HDR_PATH) -Iinclude \

	-I$(<D) -Iinclude/$(ARCH_DIR) -I ../rseq -I.. $(EXTRA_CFLAGS) \

	$(KHDR_INCLUDES)

	-fno-stack-protector -fno-PIE -fno-strict-aliasing \

	-I$(LINUX_TOOL_INCLUDE) -I$(LINUX_TOOL_ARCH_INCLUDE) \

	-I$(LINUX_HDR_PATH) -Iinclude -I$(<D) -Iinclude/$(ARCH_DIR) \

	-I ../rseq -I.. $(EXTRA_CFLAGS) $(KHDR_INCLUDES)

ifeq ($(ARCH),s390)

	CFLAGS += -march=z10

endif

ifeq ($(ARCH),x86)

ifeq ($(shell echo "void foo(void) { }" | $(CC) -march=x86-64-v2 -x c - -c -o /dev/null 2>/dev/null; echo "$$?"),0)

	CFLAGS += -march=x86-64-v2

endif

endif

ifeq ($(ARCH),arm64)

tools_dir := $(top_srcdir)/tools

arm64_tools_dir := $(tools_dir)/arch/arm64/tools/

tools/testing/selftests/kvm/guest_memfd_test.c

+1 −1
Original line number Diff line number Diff line
@@ -134,7 +134,7 @@ static void test_create_guest_memfd_invalid(struct kvm_vm *vm) 
			    size);

	}



	for (flag = 0; flag; flag <<= 1) {

	for (flag = BIT(0); flag; flag <<= 1) {

		fd = __vm_create_guest_memfd(vm, page_size, flag);

		TEST_ASSERT(fd == -1 && errno == EINVAL,

			    "guest_memfd() with flag '0x%lx' should fail with EINVAL",