iommu/amd: Do not call sleep while holding spinlock

Smatch static checker warns:
	drivers/iommu/amd/iommu_v2.c:133 free_device_state()
	warn: sleeping in atomic context

Fixes by storing the list of struct device_state in a temporary
list, and then free the memory after releasing the spinlock.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 9f968fc70d ("iommu/amd: Improve amd_iommu_v2_exit()")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20220314024321.37411-1-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Suravee Suthikulpanit 2022-03-13 21:43:21 -05:00 committed by Joerg Roedel
parent af2d861d4c
commit 5edde870d3

View File

@ -956,6 +956,7 @@ static void __exit amd_iommu_v2_exit(void)
{
struct device_state *dev_state, *next;
unsigned long flags;
LIST_HEAD(freelist);
if (!amd_iommu_v2_supported())
return;
@ -975,11 +976,20 @@ static void __exit amd_iommu_v2_exit(void)
put_device_state(dev_state);
list_del(&dev_state->list);
free_device_state(dev_state);
list_add_tail(&dev_state->list, &freelist);
}
spin_unlock_irqrestore(&state_lock, flags);
/*
* Since free_device_state waits on the count to be zero,
* we need to free dev_state outside the spinlock.
*/
list_for_each_entry_safe(dev_state, next, &freelist, list) {
list_del(&dev_state->list);
free_device_state(dev_state);
}
destroy_workqueue(iommu_wq);
}