stuartl/linux-stable
1
0
Fork 0
mirror of https://kernel.googlesource.com/pub/scm/linux/kernel/git/stable/linux-stable.git synced 2025-10-16 00:03:34 +10:00
Code Issues Releases Wiki Activity

KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass producer

Browse Source 
Take irqfds.lock when adding/deleting an IRQ bypass producer to ensure
irqfd->producer isn't modified while kvm_irq_routing_update() is running.
The only lock held when a producer is added/removed is irqbypass's mutex.

Fixes: 8727688006 ("KVM: x86: select IRQ_BYPASS_MANAGER")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250404193923.1413163-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2025-04-04 12:38:19 -07:00 committed by Paolo Bonzini
parent bcda70c56f
commit f1fb088d9c
1 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
arch/x86/kvm/x86.c
View File

@ -13561,15 +13561,22 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
{
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
struct kvm *kvm = irqfd->kvm;
int ret;
irqfd->producer = prod;
kvm_arch_start_assignment(irqfd->kvm);
spin_lock_irq(&kvm->irqfds.lock);
irqfd->producer = prod;
ret = kvm_x86_call(pi_update_irte)(irqfd->kvm,
prod->irq, irqfd->gsi, 1);
if (ret)
kvm_arch_end_assignment(irqfd->kvm);
spin_unlock_irq(&kvm->irqfds.lock);
return ret;
}
@ -13579,9 +13586,9 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
int ret;
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
struct kvm *kvm = irqfd->kvm;
WARN_ON(irqfd->producer != prod);
irqfd->producer = NULL;
/*
* When producer of consumer is unregistered, we change back to
@ -13589,12 +13596,18 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
* when the irq is masked/disabled or the consumer side (KVM
* int this case doesn't want to receive the interrupts.
*/
spin_lock_irq(&kvm->irqfds.lock);
irqfd->producer = NULL;
ret = kvm_x86_call(pi_update_irte)(irqfd->kvm,
prod->irq, irqfd->gsi, 0);
if (ret)
printk(KERN_INFO "irq bypass consumer (token %p) unregistration"
" fails: %d\n", irqfd->consumer.token, ret);
spin_unlock_irq(&kvm->irqfds.lock);
kvm_arch_end_assignment(irqfd->kvm);
}