* [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates
@ 2023-04-19 2:18 Reiji Watanabe
2023-04-19 2:18 ` [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() Reiji Watanabe
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: Reiji Watanabe @ 2023-04-19 2:18 UTC (permalink / raw)
To: Marc Zyngier, Oliver Upton, kvmarm
Cc: kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu,
Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang,
Raghavendra Rao Anata, Will Deacon, Reiji Watanabe
This series adds fixes that were missing in the patch [1].
The patch [1] added the mp_state_lock to serialize writes to
kvm_vcpu_arch::{mp_state, reset_state}, and promoted all
accessors of mp_state to {READ,WRITE}_ONCE() as readers do not
acquire the mp_state_lock.
Since the patch [1] didn't fix all the relevant code, fix the
code that weren't addressed yet.
This series is based on v6.3-rc7 with the series [2] applied.
[1] https://lore.kernel.org/all/20230327164747.2466958-2-oliver.upton@linux.dev/
[2] https://lore.kernel.org/all/20230327164747.2466958-1-oliver.upton@linux.dev/
Reiji Watanabe (2):
KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init()
KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update
mp_state
arch/arm64/kvm/arm.c | 5 ++++-
arch/arm64/kvm/psci.c | 2 +-
2 files changed, 5 insertions(+), 2 deletions(-)
--
2.40.0.396.gfff15efe05-goog
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^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() 2023-04-19 2:18 [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Reiji Watanabe @ 2023-04-19 2:18 ` Reiji Watanabe 2023-04-19 7:12 ` Marc Zyngier 2023-04-19 2:18 ` [PATCH v1 2/2] KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state Reiji Watanabe 2023-04-20 8:08 ` [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Marc Zyngier 2 siblings, 1 reply; 8+ messages in thread From: Reiji Watanabe @ 2023-04-19 2:18 UTC (permalink / raw) To: Marc Zyngier, Oliver Upton, kvmarm Cc: kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu, Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang, Raghavendra Rao Anata, Will Deacon, Reiji Watanabe kvm_arch_vcpu_ioctl_vcpu_init() doesn't acquire mp_state_lock when setting the mp_state to KVM_MP_STATE_RUNNABLE. Fix the code to acquire the lock. Signed-off-by: Reiji Watanabe <reijiw@google.com> --- arch/arm64/kvm/arm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index fbafcbbcc463..388aa4f18f21 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1244,8 +1244,11 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, */ if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) kvm_arm_vcpu_power_off(vcpu); - else + else { + spin_lock(&vcpu->arch.mp_state_lock); WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); + spin_unlock(&vcpu->arch.mp_state_lock); + } return 0; } -- 2.40.0.396.gfff15efe05-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() 2023-04-19 2:18 ` [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() Reiji Watanabe @ 2023-04-19 7:12 ` Marc Zyngier 2023-04-20 2:13 ` Reiji Watanabe 0 siblings, 1 reply; 8+ messages in thread From: Marc Zyngier @ 2023-04-19 7:12 UTC (permalink / raw) To: Reiji Watanabe Cc: Oliver Upton, kvmarm, kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu, Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang, Raghavendra Rao Anata, Will Deacon On Wed, 19 Apr 2023 03:18:51 +0100, Reiji Watanabe <reijiw@google.com> wrote: > > kvm_arch_vcpu_ioctl_vcpu_init() doesn't acquire mp_state_lock > when setting the mp_state to KVM_MP_STATE_RUNNABLE. Fix the > code to acquire the lock. > > Signed-off-by: Reiji Watanabe <reijiw@google.com> > --- > arch/arm64/kvm/arm.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index fbafcbbcc463..388aa4f18f21 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -1244,8 +1244,11 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > */ > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > kvm_arm_vcpu_power_off(vcpu); > - else > + else { > + spin_lock(&vcpu->arch.mp_state_lock); > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > + spin_unlock(&vcpu->arch.mp_state_lock); > + } > > return 0; > } I'm not entirely convinced that this fixes anything. What does the lock hazard against given that the write is atomic? But maybe a slightly more readable of this would be to expand the critical section this way: diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 4ec888fdd4f7..bb21d0c25de7 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1246,11 +1246,15 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, /* * Handle the "start in power-off" case. */ + spin_lock(&vcpu->arch.mp_state_lock); + if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) - kvm_arm_vcpu_power_off(vcpu); + __kvm_arm_vcpu_power_off(vcpu); else WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); + spin_unlock(&vcpu->arch.mp_state_lock); + return 0; } Thoughts? M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() 2023-04-19 7:12 ` Marc Zyngier @ 2023-04-20 2:13 ` Reiji Watanabe 2023-04-20 8:16 ` Marc Zyngier 0 siblings, 1 reply; 8+ messages in thread From: Reiji Watanabe @ 2023-04-20 2:13 UTC (permalink / raw) To: Marc Zyngier Cc: Oliver Upton, kvmarm, kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu, Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang, Raghavendra Rao Anata, Will Deacon Hi Marc, On Wed, Apr 19, 2023 at 08:12:45AM +0100, Marc Zyngier wrote: > On Wed, 19 Apr 2023 03:18:51 +0100, > Reiji Watanabe <reijiw@google.com> wrote: > > kvm_arch_vcpu_ioctl_vcpu_init() doesn't acquire mp_state_lock > > when setting the mp_state to KVM_MP_STATE_RUNNABLE. Fix the > > code to acquire the lock. > > > > Signed-off-by: Reiji Watanabe <reijiw@google.com> > > --- > > arch/arm64/kvm/arm.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > > index fbafcbbcc463..388aa4f18f21 100644 > > --- a/arch/arm64/kvm/arm.c > > +++ b/arch/arm64/kvm/arm.c > > @@ -1244,8 +1244,11 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > > */ > > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > > kvm_arm_vcpu_power_off(vcpu); > > - else > > + else { > > + spin_lock(&vcpu->arch.mp_state_lock); > > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > > + spin_unlock(&vcpu->arch.mp_state_lock); > > + } > > > > return 0; > > } > > I'm not entirely convinced that this fixes anything. What does the > lock hazard against given that the write is atomic? But maybe a It appears that kvm_psci_vcpu_on() expects the vCPU's mp_state to not be changed by holding the lock. Although I don't think this code practically causes any real issues now, I am a little concerned about leaving one instance that updates mpstate without acquiring the lock, in terms of future maintenance, as holding the lock won't prevent mp_state from being updated. What do you think ? > slightly more readable of this would be to expand the critical section > this way: > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 4ec888fdd4f7..bb21d0c25de7 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -1246,11 +1246,15 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > /* > * Handle the "start in power-off" case. > */ > + spin_lock(&vcpu->arch.mp_state_lock); > + > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > - kvm_arm_vcpu_power_off(vcpu); > + __kvm_arm_vcpu_power_off(vcpu); > else > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > > + spin_unlock(&vcpu->arch.mp_state_lock); > + > return 0; > } > > Thoughts? Yes, it looks better! Thank you, Reiji _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() 2023-04-20 2:13 ` Reiji Watanabe @ 2023-04-20 8:16 ` Marc Zyngier 2023-04-21 3:27 ` Reiji Watanabe 0 siblings, 1 reply; 8+ messages in thread From: Marc Zyngier @ 2023-04-20 8:16 UTC (permalink / raw) To: Reiji Watanabe Cc: Oliver Upton, kvmarm, kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu, Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang, Raghavendra Rao Anata, Will Deacon On Thu, 20 Apr 2023 03:13:02 +0100, Reiji Watanabe <reijiw@google.com> wrote: > > Hi Marc, > > On Wed, Apr 19, 2023 at 08:12:45AM +0100, Marc Zyngier wrote: > > On Wed, 19 Apr 2023 03:18:51 +0100, > > Reiji Watanabe <reijiw@google.com> wrote: > > > kvm_arch_vcpu_ioctl_vcpu_init() doesn't acquire mp_state_lock > > > when setting the mp_state to KVM_MP_STATE_RUNNABLE. Fix the > > > code to acquire the lock. > > > > > > Signed-off-by: Reiji Watanabe <reijiw@google.com> > > > --- > > > arch/arm64/kvm/arm.c | 5 ++++- > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > > > index fbafcbbcc463..388aa4f18f21 100644 > > > --- a/arch/arm64/kvm/arm.c > > > +++ b/arch/arm64/kvm/arm.c > > > @@ -1244,8 +1244,11 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > > > */ > > > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > > > kvm_arm_vcpu_power_off(vcpu); > > > - else > > > + else { > > > + spin_lock(&vcpu->arch.mp_state_lock); > > > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > > > + spin_unlock(&vcpu->arch.mp_state_lock); > > > + } > > > > > > return 0; > > > } > > > > I'm not entirely convinced that this fixes anything. What does the > > lock hazard against given that the write is atomic? But maybe a > > It appears that kvm_psci_vcpu_on() expects the vCPU's mp_state > to not be changed by holding the lock. Although I don't think this > code practically causes any real issues now, I am a little concerned > about leaving one instance that updates mpstate without acquiring the > lock, in terms of future maintenance, as holding the lock won't prevent > mp_state from being updated. > > What do you think ? Right, fair enough. It is probably better to take the lock and not have to think of this sort of things... I'm becoming more lazy by the minute! > > > slightly more readable of this would be to expand the critical section > > this way: > > > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > > index 4ec888fdd4f7..bb21d0c25de7 100644 > > --- a/arch/arm64/kvm/arm.c > > +++ b/arch/arm64/kvm/arm.c > > @@ -1246,11 +1246,15 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > > /* > > * Handle the "start in power-off" case. > > */ > > + spin_lock(&vcpu->arch.mp_state_lock); > > + > > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > > - kvm_arm_vcpu_power_off(vcpu); > > + __kvm_arm_vcpu_power_off(vcpu); > > else > > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > > > > + spin_unlock(&vcpu->arch.mp_state_lock); > > + > > return 0; > > } > > > > Thoughts? > > Yes, it looks better! Cool. I've applied this change to your patch, applied the series to the lock inversion branch, and remerged the branch in -next. We're getting there! ;-) M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() 2023-04-20 8:16 ` Marc Zyngier @ 2023-04-21 3:27 ` Reiji Watanabe 0 siblings, 0 replies; 8+ messages in thread From: Reiji Watanabe @ 2023-04-21 3:27 UTC (permalink / raw) To: Marc Zyngier Cc: Oliver Upton, kvmarm, kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu, Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang, Raghavendra Rao Anata, Will Deacon On Thu, Apr 20, 2023 at 1:16 AM Marc Zyngier <maz@kernel.org> wrote: > > On Thu, 20 Apr 2023 03:13:02 +0100, > Reiji Watanabe <reijiw@google.com> wrote: > > > > Hi Marc, > > > > On Wed, Apr 19, 2023 at 08:12:45AM +0100, Marc Zyngier wrote: > > > On Wed, 19 Apr 2023 03:18:51 +0100, > > > Reiji Watanabe <reijiw@google.com> wrote: > > > > kvm_arch_vcpu_ioctl_vcpu_init() doesn't acquire mp_state_lock > > > > when setting the mp_state to KVM_MP_STATE_RUNNABLE. Fix the > > > > code to acquire the lock. > > > > > > > > Signed-off-by: Reiji Watanabe <reijiw@google.com> > > > > --- > > > > arch/arm64/kvm/arm.c | 5 ++++- > > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > > > > index fbafcbbcc463..388aa4f18f21 100644 > > > > --- a/arch/arm64/kvm/arm.c > > > > +++ b/arch/arm64/kvm/arm.c > > > > @@ -1244,8 +1244,11 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > > > > */ > > > > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > > > > kvm_arm_vcpu_power_off(vcpu); > > > > - else > > > > + else { > > > > + spin_lock(&vcpu->arch.mp_state_lock); > > > > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > > > > + spin_unlock(&vcpu->arch.mp_state_lock); > > > > + } > > > > > > > > return 0; > > > > } > > > > > > I'm not entirely convinced that this fixes anything. What does the > > > lock hazard against given that the write is atomic? But maybe a > > > > It appears that kvm_psci_vcpu_on() expects the vCPU's mp_state > > to not be changed by holding the lock. Although I don't think this > > code practically causes any real issues now, I am a little concerned > > about leaving one instance that updates mpstate without acquiring the > > lock, in terms of future maintenance, as holding the lock won't prevent > > mp_state from being updated. > > > > What do you think ? > > Right, fair enough. It is probably better to take the lock and not > have to think of this sort of things... I'm becoming more lazy by the > minute! > > > > > > slightly more readable of this would be to expand the critical section > > > this way: > > > > > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > > > index 4ec888fdd4f7..bb21d0c25de7 100644 > > > --- a/arch/arm64/kvm/arm.c > > > +++ b/arch/arm64/kvm/arm.c > > > @@ -1246,11 +1246,15 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > > > /* > > > * Handle the "start in power-off" case. > > > */ > > > + spin_lock(&vcpu->arch.mp_state_lock); > > > + > > > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > > > - kvm_arm_vcpu_power_off(vcpu); > > > + __kvm_arm_vcpu_power_off(vcpu); > > > else > > > WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); > > > > > > + spin_unlock(&vcpu->arch.mp_state_lock); > > > + > > > return 0; > > > } > > > > > > Thoughts? > > > > Yes, it looks better! > > Cool. I've applied this change to your patch, applied the series to > the lock inversion branch, and remerged the branch in -next. > > We're getting there! ;-) Thank you, Marc! Reiji _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v1 2/2] KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state 2023-04-19 2:18 [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Reiji Watanabe 2023-04-19 2:18 ` [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() Reiji Watanabe @ 2023-04-19 2:18 ` Reiji Watanabe 2023-04-20 8:08 ` [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Marc Zyngier 2 siblings, 0 replies; 8+ messages in thread From: Reiji Watanabe @ 2023-04-19 2:18 UTC (permalink / raw) To: Marc Zyngier, Oliver Upton, kvmarm Cc: kvm, linux-arm-kernel, James Morse, Alexandru Elisei, Zenghui Yu, Suzuki K Poulose, Paolo Bonzini, Ricardo Koller, Jing Zhang, Raghavendra Rao Anata, Will Deacon, Reiji Watanabe All accessors of kvm_vcpu_arch::mp_state should be {READ,WRITE}_ONCE(), since readers of the mp_state don't acquire the mp_state_lock. Nonetheless, kvm_psci_vcpu_on() updates the mp_state without using WRITE_ONCE(). So, fix the code to update the mp_state using WRITE_ONCE. Signed-off-by: Reiji Watanabe <reijiw@google.com> --- arch/arm64/kvm/psci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index 5767e6baa61a..d046e82e3723 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -110,7 +110,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) */ smp_wmb(); - vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; + WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); kvm_vcpu_wake_up(vcpu); out_unlock: -- 2.40.0.396.gfff15efe05-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates 2023-04-19 2:18 [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Reiji Watanabe 2023-04-19 2:18 ` [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() Reiji Watanabe 2023-04-19 2:18 ` [PATCH v1 2/2] KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state Reiji Watanabe @ 2023-04-20 8:08 ` Marc Zyngier 2 siblings, 0 replies; 8+ messages in thread From: Marc Zyngier @ 2023-04-20 8:08 UTC (permalink / raw) To: kvmarm, Reiji Watanabe, Oliver Upton Cc: Suzuki K Poulose, Raghavendra Rao Anata, James Morse, Paolo Bonzini, linux-arm-kernel, Zenghui Yu, Will Deacon, Ricardo Koller, Alexandru Elisei, Jing Zhang, kvm On Tue, 18 Apr 2023 19:18:50 -0700, Reiji Watanabe wrote: > This series adds fixes that were missing in the patch [1]. > > The patch [1] added the mp_state_lock to serialize writes to > kvm_vcpu_arch::{mp_state, reset_state}, and promoted all > accessors of mp_state to {READ,WRITE}_ONCE() as readers do not > acquire the mp_state_lock. > > [...] Applied to next, thanks! [1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() commit: 4ff910be01c0ca28c2ea8b354dd47a3a17524489 [2/2] KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state commit: a189884bdc9238aeba941c50f02e25eb584fafed Cheers, M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2023-04-21 3:28 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2023-04-19 2:18 [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Reiji Watanabe 2023-04-19 2:18 ` [PATCH v1 1/2] KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init() Reiji Watanabe 2023-04-19 7:12 ` Marc Zyngier 2023-04-20 2:13 ` Reiji Watanabe 2023-04-20 8:16 ` Marc Zyngier 2023-04-21 3:27 ` Reiji Watanabe 2023-04-19 2:18 ` [PATCH v1 2/2] KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state Reiji Watanabe 2023-04-20 8:08 ` [PATCH v1 0/2] KVM: arm64: Fix bugs related to mp_state updates Marc Zyngier
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