Commit 0499add8 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

Merge tag 'kvm-x86-fixes-6.19-rc1' of https://github.com/kvm-x86/linux into HEAD 

KVM fixes for 6.19-rc1

 - Add a missing "break" to fix param parsing in the rseq selftest.

 - Apply runtime updates to the _current_ CPUID when userspace is setting
   CPUID, e.g. as part of vCPU hotplug, to fix a false positive and to avoid
   dropping the pending update.

 - Disallow toggling KVM_MEM_GUEST_MEMFD on an existing memslot, as it's not
   supported by KVM and leads to a use-after-free due to KVM failing to unbind
   the memslot from the previously-associated guest_memfd instance.

 - Harden against similar KVM_MEM_GUEST_MEMFD goofs, and prepare for supporting
   flags-only changes on KVM_MEM_GUEST_MEMFD memlslots, e.g. for dirty logging.

 - Set exit_code[63:32] to -1 (all 0xffs) when synthesizing a nested
   SVM_EXIT_ERR (a.k.a. VMEXIT_INVALID) #VMEXIT, as VMEXIT_INVALID is defined
   as -1ull (a 64-bit value).

 - Update SVI when activating APICv to fix a bug where a post-activation EOI
   for an in-service IRQ would effective be lost due to SVI being stale.

 - Immediately refresh APICv controls (if necessary) on a nested VM-Exit
   instead of deferring the update via KVM_REQ_APICV_UPDATE, as the request is
   effectively ignored because KVM thinks the vCPU already has the correct
   APICv settings.
parents ea1013c1 29763138

arch/x86/kvm/cpuid.c

+9 −2
Original line number Diff line number Diff line
@@ -509,11 +509,18 @@ static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2, 
	u32 vcpu_caps[NR_KVM_CPU_CAPS];

	int r;



	/*

	 * Apply pending runtime CPUID updates to the current CPUID entries to

	 * avoid false positives due to mismatches on KVM-owned feature flags.

	 */

	if (vcpu->arch.cpuid_dynamic_bits_dirty)

		kvm_update_cpuid_runtime(vcpu);



	/*

	 * Swap the existing (old) entries with the incoming (new) entries in

	 * order to massage the new entries, e.g. to account for dynamic bits

	 * that KVM controls, without clobbering the current guest CPUID, which

	 * KVM needs to preserve in order to unwind on failure.

	 * that KVM controls, without losing the current guest CPUID, which KVM

	 * needs to preserve in order to unwind on failure.

	 *

	 * Similarly, save the vCPU's current cpu_caps so that the capabilities

	 * can be updated alongside the CPUID entries when performing runtime

arch/x86/kvm/svm/nested.c

+2 −2
Original line number Diff line number Diff line
@@ -985,7 +985,7 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu) 
	if (!nested_vmcb_check_save(vcpu) ||

	    !nested_vmcb_check_controls(vcpu)) {

		vmcb12->control.exit_code    = SVM_EXIT_ERR;

		vmcb12->control.exit_code_hi = 0;

		vmcb12->control.exit_code_hi = -1u;

		vmcb12->control.exit_info_1  = 0;

		vmcb12->control.exit_info_2  = 0;

		goto out;
@@ -1018,7 +1018,7 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu) 
	svm->soft_int_injected = false;



	svm->vmcb->control.exit_code    = SVM_EXIT_ERR;

	svm->vmcb->control.exit_code_hi = 0;

	svm->vmcb->control.exit_code_hi = -1u;

	svm->vmcb->control.exit_info_1  = 0;

	svm->vmcb->control.exit_info_2  = 0;

arch/x86/kvm/svm/svm.c

+2 −0
Original line number Diff line number Diff line
@@ -2443,6 +2443,7 @@ static bool check_selective_cr0_intercepted(struct kvm_vcpu *vcpu, 


	if (cr0 ^ val) {

		svm->vmcb->control.exit_code = SVM_EXIT_CR0_SEL_WRITE;

		svm->vmcb->control.exit_code_hi = 0;

		ret = (nested_svm_exit_handled(svm) == NESTED_EXIT_DONE);

	}
@@ -4617,6 +4618,7 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu, 
	if (static_cpu_has(X86_FEATURE_NRIPS))

		vmcb->control.next_rip  = info->next_rip;

	vmcb->control.exit_code = icpt_info.exit_code;

	vmcb->control.exit_code_hi = 0;

	vmexit = nested_svm_exit_handled(svm);



	ret = (vmexit == NESTED_EXIT_DONE) ? X86EMUL_INTERCEPTED

arch/x86/kvm/svm/svm.h

+4 −3
Original line number Diff line number Diff line
@@ -762,6 +762,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm); 
static inline int nested_svm_simple_vmexit(struct vcpu_svm *svm, u32 exit_code)

{

	svm->vmcb->control.exit_code	= exit_code;

	svm->vmcb->control.exit_code_hi	= 0;

	svm->vmcb->control.exit_info_1	= 0;

	svm->vmcb->control.exit_info_2	= 0;

	return nested_svm_vmexit(svm);

arch/x86/kvm/vmx/nested.c

+2 −1
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include "trace.h"

#include "vmx.h"

#include "smm.h"

#include "x86_ops.h"



static bool __read_mostly enable_shadow_vmcs = 1;

module_param_named(enable_shadow_vmcs, enable_shadow_vmcs, bool, S_IRUGO);
@@ -5165,7 +5166,7 @@ void __nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 vm_exit_reason, 


	if (vmx->nested.update_vmcs01_apicv_status) {

		vmx->nested.update_vmcs01_apicv_status = false;

		kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);

		vmx_refresh_apicv_exec_ctrl(vcpu);

	}



	if (vmx->nested.update_vmcs01_hwapic_isr) {