From: Sean Christopherson <seanjc@google.com>
To: Marc Zyngier <maz@kernel.org>, Oliver Upton <oupton@kernel.org>,
Tianrui Zhao <zhaotianrui@loongson.cn>,
Bibo Mao <maobibo@loongson.cn>,
Huacai Chen <chenhuacai@kernel.org>,
Madhavan Srinivasan <maddy@linux.ibm.com>,
Anup Patel <anup@brainfault.org>, Paul Walmsley <pjw@kernel.org>,
Palmer Dabbelt <palmer@dabbelt.com>,
Albert Ou <aou@eecs.berkeley.edu>,
Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: Fuad Tabba <fuad.tabba@linux.dev>,
Joey Gouly <joey.gouly@arm.com>,
Steffen Eiden <seiden@linux.ibm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Zenghui Yu <yuzenghui@huawei.com>,
Nicholas Piggin <npiggin@gmail.com>,
Atish Patra <atish.patra@linux.dev>,
Alexandre Ghiti <alex@ghiti.fr>,
linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
kvm@vger.kernel.org, loongarch@lists.linux.dev,
linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org,
linux-kernel@vger.kernel.org,
Stefan Teodorescu <fane@google.com>
Subject: [PATCH 6/7] KVM: Plumb the full request into __kvm_vcpu_kick()
Date: Wed, 28 Oct 2026 12:02:58 -0700 [thread overview]
Message-ID: <20261028190259.1819571-7-seanjc@google.com> (raw)
In-Reply-To: <20261028190259.1819571-1-seanjc@google.com>
Plumb the full request instead of just a "wait" boolean into
__kvm_vcpu_kick() so that it can use kvm_request_needs_ipi() instead of
the flawed kvm_vcpu_should_kick().
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/powerpc/include/asm/kvm_ppc.h | 2 +-
include/linux/kvm_host.h | 6 +++---
virt/kvm/kvm_main.c | 17 +++++++++--------
3 files changed, 13 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index bbe7378ad0ef..011dc422af78 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -38,7 +38,7 @@
*/
static inline void kvmppc_vcpu_kick(struct kvm_vcpu *vcpu)
{
- __kvm_vcpu_kick(vcpu, false, true);
+ __kvm_vcpu_kick(vcpu, 0, true);
}
/*
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 9db42f58c561..035b1bdd8c09 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1570,11 +1570,11 @@ void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu);
bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu);
#ifndef CONFIG_S390
-void __kvm_vcpu_kick(struct kvm_vcpu *vcpu, bool wait, bool force);
+void __kvm_vcpu_kick(struct kvm_vcpu *vcpu, int request, bool force);
static inline void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
{
- __kvm_vcpu_kick(vcpu, false, false);
+ __kvm_vcpu_kick(vcpu, 0, false);
}
#endif
@@ -2314,7 +2314,7 @@ static __always_inline void kvm_make_request(int req, struct kvm_vcpu *vcpu)
static inline void kvm_make_request_and_kick(int req, struct kvm_vcpu *vcpu)
{
kvm_make_request(req, vcpu);
- __kvm_vcpu_kick(vcpu, req & KVM_REQUEST_WAIT, false);
+ __kvm_vcpu_kick(vcpu, req, false);
}
#endif
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e1a9da8b43d7..f1792256576b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3913,7 +3913,7 @@ EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_vcpu_wake_up);
/*
* Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
*/
-void __kvm_vcpu_kick(struct kvm_vcpu *vcpu, bool wait, bool force)
+void __kvm_vcpu_kick(struct kvm_vcpu *vcpu, int req, bool force)
{
int me, cpu;
@@ -3948,14 +3948,15 @@ void __kvm_vcpu_kick(struct kvm_vcpu *vcpu, bool wait, bool force)
cpu = READ_ONCE(vcpu->cpu);
if (cpu != me && (unsigned int)cpu < nr_cpu_ids && cpu_online(cpu)) {
/*
- * Use a reschedule IPI to kick the vCPU if the caller
- * doesn't need to wait for a response, as KVM allows
- * kicking vCPUs while IRQs are disabled, but using the
- * SMP function call framework with IRQs disabled can
- * deadlock due to taking cross-CPU locks.
+ * Use a reschedule IPI to kick the vCPU if the request
+ * doesn't need to wait for a response (or there is no
+ * request), as KVM allows kicking vCPUs while IRQs are
+ * disabled, but using the SMP function call framework
+ * with IRQs disabled can deadlock due to taking cross-
+ * CPU locks.
*/
- if (wait)
- smp_call_function_single(cpu, ack_kick, NULL, wait);
+ if (req & KVM_REQUEST_WAIT)
+ smp_call_function_single(cpu, ack_kick, NULL, true);
else
smp_send_reschedule(cpu);
}
--
2.56.0.313.g2479322e68-goog
next prev parent reply other threads:[~2026-10-28 19:03 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-28 19:02 [PATCH 0/7] KVM: Ensure WAIT requests actually wait Sean Christopherson
2026-10-28 19:02 ` [PATCH 1/7] KVM: s390: Drop unused and unreachable kvm_arch_vcpu_should_kick() Sean Christopherson
2026-10-28 19:02 ` [PATCH 2/7] KVM: Add a @force param to __kvm_vcpu_kick() for PPC backwards compatibility Sean Christopherson
2026-10-28 19:02 ` [PATCH 3/7] KVM: PPC: Explicitly force IPIs when directly kicking vCPUs Sean Christopherson
2026-10-28 19:02 ` [PATCH 4/7] KVM: MIPS: Rework kvm_arch_vcpu_should_kick() to use standard implementation Sean Christopherson
2026-10-28 19:02 ` [PATCH 5/7] KVM: Move kvm_arch_vcpu_should_kick() to common code as kvm_vcpu_should_kick() Sean Christopherson
2026-10-28 19:02 ` Sean Christopherson [this message]
2026-10-28 19:02 ` [PATCH 7/7] KVM: Drop kvm_vcpu_should_kick() and use kvm_request_needs_ipi() Sean Christopherson
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