On 6/11/2025 6:57 AM, Sean Christopherson wrote:
> 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>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.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)