Commit 2e7577cd authored by Li RongQing's avatar Li RongQing Committed by Wei Liu
Browse files

mshv: fix SRCU protection in irqfd resampler ack handler 



Replace hlist_for_each_entry_rcu() with hlist_for_each_entry_srcu()
in mshv_irqfd_resampler_ack() to correctly handle SRCU-protected
linked list traversal.

The function uses SRCU (sleepable RCU) synchronization via
partition->pt_irq_srcu, but was incorrectly using the RCU variant
for list iteration. This could lead to race conditions when the
list is modified concurrently.

Also add srcu_read_lock_held() assertion as required by
hlist_for_each_entry_srcu() to ensure we're in the proper
read-side critical section.

Fixes: 621191d7 ("Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMs")
Signed-off-by: default avatarLi RongQing <lirongqing@baidu.com>
Reviewed-by: default avatarAnirudh Rayabharam (Microsoft) <anirudh@anirudhrb.com>
Acked-by: default avatarStanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
parent 51515bfc

drivers/hv/mshv_eventfd.c

+3 −2
Original line number Diff line number Diff line
@@ -87,8 +87,9 @@ static void mshv_irqfd_resampler_ack(struct mshv_irq_ack_notifier *mian) 


	idx = srcu_read_lock(&partition->pt_irq_srcu);



	hlist_for_each_entry_rcu(irqfd, &resampler->rsmplr_irqfd_list,

				 irqfd_resampler_hnode) {

	hlist_for_each_entry_srcu(irqfd, &resampler->rsmplr_irqfd_list,

				 irqfd_resampler_hnode,

				 srcu_read_lock_held(&partition->pt_irq_srcu)) {

		if (hv_should_clear_interrupt(irqfd->irqfd_lapic_irq.lapic_control.interrupt_type))

			hv_call_clear_virtual_interrupt(partition->pt_id);