This is a note to let you know that I've just added the patch titled KVM: VMX: Convert launched argument to flags to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kvm-vmx-convert-launched-argument-to-flags.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Wed Oct 5 12:28:43 PM CEST 2022 From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx> Date: Mon, 3 Oct 2022 10:10:28 -0300 Subject: KVM: VMX: Convert launched argument to flags To: stable@xxxxxxxxxxxxxxx Cc: x86@xxxxxxxxxx, kvm@xxxxxxxxxxxxxxx, bp@xxxxxxxxx, pbonzini@xxxxxxxxxx, peterz@xxxxxxxxxxxxx, jpoimboe@xxxxxxxxxx Message-ID: <20221003131038.12645-28-cascardo@xxxxxxxxxxxxx> From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx> commit bb06650634d3552c0f8557e9d16aa1a408040e28 upstream. Convert __vmx_vcpu_run()'s 'launched' argument to 'flags', in preparation for doing SPEC_CTRL handling immediately after vmexit, which will need another flag. This is much easier than adding a fourth argument, because this code supports both 32-bit and 64-bit, and the fourth argument on 32-bit would have to be pushed on the stack. Note that __vmx_vcpu_run_flags() is called outside of the noinstr critical section because it will soon start calling potentially traceable functions. Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kvm/vmx/nested.c | 2 +- arch/x86/kvm/vmx/run_flags.h | 7 +++++++ arch/x86/kvm/vmx/vmenter.S | 9 +++++---- arch/x86/kvm/vmx/vmx.c | 12 +++++++++++- arch/x86/kvm/vmx/vmx.h | 5 ++++- 5 files changed, 28 insertions(+), 7 deletions(-) create mode 100644 arch/x86/kvm/vmx/run_flags.h --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -2865,7 +2865,7 @@ static int nested_vmx_check_vmentry_hw(s } vm_fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs, - vmx->loaded_vmcs->launched); + __vmx_vcpu_run_flags(vmx)); if (vmx->msr_autoload.host.nr) vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr); --- /dev/null +++ b/arch/x86/kvm/vmx/run_flags.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __KVM_X86_VMX_RUN_FLAGS_H +#define __KVM_X86_VMX_RUN_FLAGS_H + +#define VMX_RUN_VMRESUME (1 << 0) + +#endif /* __KVM_X86_VMX_RUN_FLAGS_H */ --- a/arch/x86/kvm/vmx/vmenter.S +++ b/arch/x86/kvm/vmx/vmenter.S @@ -4,6 +4,7 @@ #include <asm/bitsperlong.h> #include <asm/kvm_vcpu_regs.h> #include <asm/nospec-branch.h> +#include "run_flags.h" #define WORD_SIZE (BITS_PER_LONG / 8) @@ -33,7 +34,7 @@ * __vmx_vcpu_run - Run a vCPU via a transition to VMX guest mode * @vmx: struct vcpu_vmx * (forwarded to vmx_update_host_rsp) * @regs: unsigned long * (to guest registers) - * @launched: %true if the VMCS has been launched + * @flags: VMX_RUN_VMRESUME: use VMRESUME instead of VMLAUNCH * * Returns: * 0 on VM-Exit, 1 on VM-Fail @@ -58,7 +59,7 @@ ENTRY(__vmx_vcpu_run) */ push %_ASM_ARG2 - /* Copy @launched to BL, _ASM_ARG3 is volatile. */ + /* Copy @flags to BL, _ASM_ARG3 is volatile. */ mov %_ASM_ARG3B, %bl lea (%_ASM_SP), %_ASM_ARG2 @@ -68,7 +69,7 @@ ENTRY(__vmx_vcpu_run) mov (%_ASM_SP), %_ASM_AX /* Check if vmlaunch or vmresume is needed */ - testb %bl, %bl + testb $VMX_RUN_VMRESUME, %bl /* Load guest registers. Don't clobber flags. */ mov VCPU_RBX(%_ASM_AX), %_ASM_BX @@ -91,7 +92,7 @@ ENTRY(__vmx_vcpu_run) mov VCPU_RAX(%_ASM_AX), %_ASM_AX /* Check EFLAGS.ZF from 'testb' above */ - je .Lvmlaunch + jz .Lvmlaunch /* * If VMRESUME/VMLAUNCH and corresponding vmexit succeed, execution resumes at --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -863,6 +863,16 @@ static bool msr_write_intercepted(struct return true; } +unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx) +{ + unsigned int flags = 0; + + if (vmx->loaded_vmcs->launched) + flags |= VMX_RUN_VMRESUME; + + return flags; +} + static void clear_atomic_switch_msr_special(struct vcpu_vmx *vmx, unsigned long entry, unsigned long exit) { @@ -6627,7 +6637,7 @@ static void vmx_vcpu_run(struct kvm_vcpu write_cr2(vcpu->arch.cr2); vmx->fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs, - vmx->loaded_vmcs->launched); + __vmx_vcpu_run_flags(vmx)); vcpu->arch.cr2 = read_cr2(); --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -10,6 +10,7 @@ #include "capabilities.h" #include "ops.h" #include "vmcs.h" +#include "run_flags.h" extern const u32 vmx_msr_index[]; extern u64 host_efer; @@ -336,7 +337,9 @@ void vmx_set_virtual_apic_mode(struct kv struct shared_msr_entry *find_msr_entry(struct vcpu_vmx *vmx, u32 msr); void pt_update_intercept_for_msr(struct vcpu_vmx *vmx); void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp); -bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched); +unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx); +bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, + unsigned int flags); #define POSTED_INTR_ON 0 #define POSTED_INTR_SN 1 Patches currently in stable-queue which might be from cascardo@xxxxxxxxxxxxx are queue-5.4/x86-speculation-disable-rrsba-behavior.patch queue-5.4/kvm-vmx-flatten-__vmx_vcpu_run.patch queue-5.4/x86-kvm-vmx-make-noinstr-clean.patch queue-5.4/revert-x86-speculation-add-rsb-vm-exit-protections.patch queue-5.4/kvm-vmx-fix-ibrs-handling-after-vmexit.patch queue-5.4/kvm-vmx-prevent-guest-rsb-poisoning-attacks-with-eibrs.patch queue-5.4/kvm-nvmx-use-__vmx_vcpu_run-in-nested_vmx_check_vmentry_hw.patch queue-5.4/x86-bugs-keep-a-per-cpu-ia32_spec_ctrl-value.patch queue-5.4/x86-cpu-amd-enumerate-btc_no.patch queue-5.4/x86-speculation-fix-firmware-entry-spec_ctrl-handling.patch queue-5.4/x86-speculation-add-spectre_v2-ibrs-option-to-support-kernel-ibrs.patch queue-5.4/x86-cpu-add-consistent-cpu-match-macros.patch queue-5.4/x86-speculation-remove-x86_spec_ctrl_mask.patch queue-5.4/x86-bugs-add-cannon-lake-to-retbleed-affected-cpu-list.patch queue-5.4/x86-bugs-warn-when-ibrs-mitigation-is-selected-on-enhanced-ibrs-parts.patch queue-5.4/x86-speculation-fill-rsb-on-vmexit-for-ibrs.patch queue-5.4/x86-cpu-add-a-steppings-field-to-struct-x86_cpu_id.patch queue-5.4/kvm-vmx-convert-launched-argument-to-flags.patch queue-5.4/x86-common-stamp-out-the-stepping-madness.patch queue-5.4/x86-bugs-split-spectre_v2_select_mitigation-and-spectre_v2_user_select_mitigation.patch queue-5.4/x86-bugs-report-intel-retbleed-vulnerability.patch queue-5.4/x86-speculation-change-fill_return_buffer-to-work-with-objtool.patch queue-5.4/x86-cpufeatures-move-retpoline-flags-to-word-11.patch queue-5.4/x86-speculation-fix-spec_ctrl-write-on-smt-state-change.patch queue-5.4/kvm-vmx-use-test-reg-reg-instead-of-cmp-0-reg-in-vmenter.s.patch queue-5.4/x86-bugs-optimize-spec_ctrl-msr-writes.patch queue-5.4/x86-bugs-report-amd-retbleed-vulnerability.patch queue-5.4/x86-speculation-fix-rsb-filling-with-config_retpoline-n.patch queue-5.4/intel_idle-disable-ibrs-during-long-idle.patch queue-5.4/x86-speculation-use-declare_per_cpu-for-x86_spec_ctrl_current.patch queue-5.4/x86-entry-remove-skip_r11rcx.patch queue-5.4/x86-speculation-use-cached-host-spec_ctrl-value-for-guest-entry-exit.patch queue-5.4/x86-devicetable-move-x86-specific-macro-out-of-generic-code.patch queue-5.4/x86-bugs-add-amd-retbleed-boot-parameter.patch queue-5.4/x86-entry-add-kernel-ibrs-implementation.patch queue-5.4/revert-x86-cpu-add-a-steppings-field-to-struct-x86_cpu_id.patch queue-5.4/x86-speculation-add-rsb-vm-exit-protections.patch