archives/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-03-08 01:04:41 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

mshv: clear eventfd counter on irqfd shutdown

Browse source 
While unhooking from the irqfd waitqueue, clear the internal eventfd
counter by using eventfd_ctx_remove_wait_queue() instead of
remove_wait_queue(), preventing potential spurious interrupts. This
removes the need to store a pointer into the workqueue, as the eventfd
already keeps track of it.

This mimicks what other similar subsystems do on their equivalent paths
with their irqfds (KVM, Xen, ACRN support, etc).

Signed-off-by: Carlos López <clopez@suse.de>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
This commit is contained in:
Carlos López 2026-01-22 12:41:31 +01:00 • committed by Wei Liu
parent 5ed8cbcacc
commit 2b4246153e
2 changed files with 2 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

5
drivers/hv/mshv_eventfd.c
View file

@ -247,12 +247,13 @@ static void mshv_irqfd_shutdown(struct work_struct *work)
{
struct mshv_irqfd *irqfd =
container_of(work, struct mshv_irqfd, irqfd_shutdown);
u64 cnt;
/*
* Synchronize with the wait-queue and unhook ourselves to prevent
* further events.
*/
remove_wait_queue(irqfd->irqfd_wqh, &irqfd->irqfd_wait);
eventfd_ctx_remove_wait_queue(irqfd->irqfd_eventfd_ctx, &irqfd->irqfd_wait, &cnt);
if (irqfd->irqfd_resampler) {
mshv_irqfd_resampler_shutdown(irqfd);
@ -371,8 +372,6 @@ static void mshv_irqfd_queue_proc(struct file *file, wait_queue_head_t *wqh,
struct mshv_irqfd *irqfd =
container_of(polltbl, struct mshv_irqfd, irqfd_polltbl);
irqfd->irqfd_wqh = wqh;
/*
* TODO: Ensure there isn't already an exclusive, priority waiter, e.g.
* that the irqfd isn't already bound to another partition. Only the

1
drivers/hv/mshv_eventfd.h
View file

@ -32,7 +32,6 @@ struct mshv_irqfd {
struct mshv_lapic_irq irqfd_lapic_irq;
struct hlist_node irqfd_hnode;
poll_table irqfd_polltbl;
wait_queue_head_t *irqfd_wqh;
wait_queue_entry_t irqfd_wait;
struct work_struct irqfd_shutdown;
struct mshv_irqfd_resampler *irqfd_resampler;