Daniel Marcovitch 13ed255248 iommu/amd/iommu_v2: Fix pasid_state refcount dec hit 0 warning on pasid unbind ... [ Upstream commit 534103bcd5 ] When unbinding pasid - a race condition exists vs outstanding page faults. To prevent this, the pasid_state object contains a refcount. * set to 1 on pasid bind * incremented on each ppr notification start * decremented on each ppr notification done * decremented on pasid unbind Since refcount_dec assumes that refcount will never reach 0: the current implementation causes the following to be invoked on pasid unbind: REFCOUNT_WARN("decrement hit 0; leaking memory") Fix this issue by changing refcount_dec to refcount_dec_and_test to explicitly handle refcount=1. Fixes: 8bc54824da ("iommu/amd: Convert from atomic_t to refcount_t on pasid_state->count") Signed-off-by: Daniel Marcovitch <dmarcovitch@nvidia.com> Signed-off-by: Vasant Hegde <vasant.hegde@amd.com> Link: https://lore.kernel.org/r/20230609105146.7773-2-vasant.hegde@amd.com Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-09-13 09:42:50 +02:00
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Kconfig	…
Makefile	…
amd_iommu.h	…
amd_iommu_types.h	iommu/amd: Introduce Disable IRTE Caching Support	2023-08-23 17:52:21 +02:00
debugfs.c	…
init.c	iommu/amd: Introduce Disable IRTE Caching Support	2023-08-23 17:52:21 +02:00
io_pgtable.c	…
io_pgtable_v2.c	…
iommu.c	…
iommu_v2.c	iommu/amd/iommu_v2: Fix pasid_state refcount dec hit 0 warning on pasid unbind	2023-09-13 09:42:50 +02:00
quirks.c	…