From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Chao Gao <chao.gao@intel.com>, Borislav Petkov <bp@alien8.de>,
Xin Li <xin@zytor.com>, Dapeng Mi <dapeng1.mi@linux.intel.com>,
Francesco Lavra <francescolavra.fl@gmail.com>,
Manali Shukla <Manali.Shukla@amd.com>
Subject: [PATCH v2 07/32] KVM: x86: Use non-atomic bit ops to manipulate "shadow" MSR intercepts
Date: Tue, 10 Jun 2025 15:57:12 -0700 [thread overview]
Message-ID: <20250610225737.156318-8-seanjc@google.com> (raw)
In-Reply-To: <20250610225737.156318-1-seanjc@google.com>
Manipulate the MSR bitmaps using non-atomic bit ops APIs (two underscores),
as the bitmaps are per-vCPU and are only ever accessed while vcpu->mutex is
held.
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/svm/svm.c | 12 ++++++------
arch/x86/kvm/vmx/vmx.c | 8 ++++----
2 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 7e39b9df61f1..ec97ea1d7b38 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -789,14 +789,14 @@ static void set_shadow_msr_intercept(struct kvm_vcpu *vcpu, u32 msr, int read,
/* Set the shadow bitmaps to the desired intercept states */
if (read)
- set_bit(slot, svm->shadow_msr_intercept.read);
+ __set_bit(slot, svm->shadow_msr_intercept.read);
else
- clear_bit(slot, svm->shadow_msr_intercept.read);
+ __clear_bit(slot, svm->shadow_msr_intercept.read);
if (write)
- set_bit(slot, svm->shadow_msr_intercept.write);
+ __set_bit(slot, svm->shadow_msr_intercept.write);
else
- clear_bit(slot, svm->shadow_msr_intercept.write);
+ __clear_bit(slot, svm->shadow_msr_intercept.write);
}
static bool valid_msr_intercept(u32 index)
@@ -862,8 +862,8 @@ static void set_msr_interception_bitmap(struct kvm_vcpu *vcpu, u32 *msrpm,
bit_write = 2 * (msr & 0x0f) + 1;
tmp = msrpm[offset];
- read ? clear_bit(bit_read, &tmp) : set_bit(bit_read, &tmp);
- write ? clear_bit(bit_write, &tmp) : set_bit(bit_write, &tmp);
+ read ? __clear_bit(bit_read, &tmp) : __set_bit(bit_read, &tmp);
+ write ? __clear_bit(bit_write, &tmp) : __set_bit(bit_write, &tmp);
msrpm[offset] = tmp;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 9ff00ae9f05a..8f7fe04a1998 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4029,9 +4029,9 @@ void vmx_disable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type)
idx = vmx_get_passthrough_msr_slot(msr);
if (idx >= 0) {
if (type & MSR_TYPE_R)
- clear_bit(idx, vmx->shadow_msr_intercept.read);
+ __clear_bit(idx, vmx->shadow_msr_intercept.read);
if (type & MSR_TYPE_W)
- clear_bit(idx, vmx->shadow_msr_intercept.write);
+ __clear_bit(idx, vmx->shadow_msr_intercept.write);
}
if ((type & MSR_TYPE_R) &&
@@ -4071,9 +4071,9 @@ void vmx_enable_intercept_for_msr(struct kvm_vcpu *vcpu, u32 msr, int type)
idx = vmx_get_passthrough_msr_slot(msr);
if (idx >= 0) {
if (type & MSR_TYPE_R)
- set_bit(idx, vmx->shadow_msr_intercept.read);
+ __set_bit(idx, vmx->shadow_msr_intercept.read);
if (type & MSR_TYPE_W)
- set_bit(idx, vmx->shadow_msr_intercept.write);
+ __set_bit(idx, vmx->shadow_msr_intercept.write);
}
if (type & MSR_TYPE_R)
--
2.50.0.rc0.642.g800a2b2222-goog
next prev parent reply other threads:[~2025-06-10 22:57 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-10 22:57 [PATCH v2 00/32] KVM: x86: Clean up MSR interception code Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 01/32] KVM: SVM: Disable interception of SPEC_CTRL iff the MSR exists for the guest Sean Christopherson
2025-06-11 4:38 ` Binbin Wu
2025-06-11 7:14 ` Binbin Wu
2025-06-10 22:57 ` [PATCH v2 02/32] KVM: SVM: Allocate IOPM pages after initial setup in svm_hardware_setup() Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 03/32] KVM: SVM: Don't BUG if setting up the MSR intercept bitmaps fails Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 04/32] KVM: SVM: Tag MSR bitmap initialization helpers with __init Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 05/32] KVM: SVM: Use ARRAY_SIZE() to iterate over direct_access_msrs Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 06/32] KVM: SVM: Kill the VM instead of the host if MSR interception is buggy Sean Christopherson
2025-06-11 2:16 ` Mi, Dapeng
2025-06-10 22:57 ` Sean Christopherson [this message]
2025-06-11 6:38 ` [PATCH v2 07/32] KVM: x86: Use non-atomic bit ops to manipulate "shadow" MSR intercepts Binbin Wu
2025-06-10 22:57 ` [PATCH v2 08/32] KVM: SVM: Massage name and param of helper that merges vmcb01 and vmcb12 MSRPMs Sean Christopherson
2025-06-11 2:22 ` Mi, Dapeng
2025-06-10 22:57 ` [PATCH v2 09/32] KVM: SVM: Clean up macros related to architectural MSRPM definitions Sean Christopherson
2025-06-11 6:09 ` Binbin Wu
2025-06-10 22:57 ` [PATCH v2 10/32] KVM: nSVM: Use dedicated array of MSRPM offsets to merge L0 and L1 bitmaps Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 11/32] KVM: nSVM: Omit SEV-ES specific passthrough MSRs from L0+L1 bitmap merge Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 12/32] KVM: nSVM: Don't initialize vmcb02 MSRPM with vmcb01's "always passthrough" Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 13/32] KVM: SVM: Add helpers for accessing MSR bitmap that don't rely on offsets Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 14/32] KVM: SVM: Implement and adopt VMX style MSR intercepts APIs Sean Christopherson
2025-06-11 7:31 ` Binbin Wu
2025-06-10 22:57 ` [PATCH v2 15/32] KVM: SVM: Pass through GHCB MSR if and only if VM is an SEV-ES guest Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 16/32] KVM: SVM: Drop "always" flag from list of possible passthrough MSRs Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 17/32] KVM: x86: Move definition of X2APIC_MSR() to lapic.h Sean Christopherson
2025-06-11 2:29 ` Mi, Dapeng
2025-06-10 22:57 ` [PATCH v2 18/32] KVM: VMX: Manually recalc all MSR intercepts on userspace MSR filter change Sean Christopherson
2025-06-11 6:52 ` Binbin Wu
2025-06-10 22:57 ` [PATCH v2 19/32] KVM: SVM: " Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 20/32] KVM: x86: Rename msr_filter_changed() => recalc_msr_intercepts() Sean Christopherson
2025-06-11 7:09 ` Binbin Wu
2025-06-10 22:57 ` [PATCH v2 21/32] KVM: SVM: Rename init_vmcb_after_set_cpuid() to make it intercepts specific Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 22/32] KVM: SVM: Fold svm_vcpu_init_msrpm() into its sole caller Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 23/32] KVM: SVM: Merge "after set CPUID" intercept recalc helpers Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 24/32] KVM: SVM: Drop explicit check on MSRPM offset when emulating SEV-ES accesses Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 25/32] KVM: SVM: Move svm_msrpm_offset() to nested.c Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 26/32] KVM: SVM: Store MSRPM pointer as "void *" instead of "u32 *" Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 27/32] KVM: nSVM: Access MSRPM in 4-byte chunks only for merging L0 and L1 bitmaps Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 28/32] KVM: SVM: Return -EINVAL instead of MSR_INVALID to signal out-of-range MSR Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 29/32] KVM: nSVM: Merge MSRPM in 64-bit chunks on 64-bit kernels Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 30/32] KVM: SVM: Add a helper to allocate and initialize permissions bitmaps Sean Christopherson
2025-06-10 22:57 ` [PATCH v2 31/32] KVM: x86: Simplify userspace filter logic when disabling MSR interception Sean Christopherson
2025-06-11 2:35 ` Mi, Dapeng
2025-06-10 22:57 ` [PATCH v2 32/32] KVM: selftests: Verify KVM disable interception (for userspace) on filter change Sean Christopherson
2025-06-24 19:38 ` [PATCH v2 00/32] KVM: x86: Clean up MSR interception code Sean Christopherson
2025-06-25 12:03 ` Manali Shukla
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