From: Suravee Suthikulpanit suravee.suthikulpanit@amd.com
[ Upstream commit 5edde870d3283edeaa27ab62ac4fac5ee8cae35a ]
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: 9f968fc70d85 ("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.c... Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/amd/iommu_v2.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/iommu_v2.c b/drivers/iommu/amd/iommu_v2.c index e56b137ceabd..afb3efd565b7 100644 --- a/drivers/iommu/amd/iommu_v2.c +++ b/drivers/iommu/amd/iommu_v2.c @@ -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); }