Levi Yun 8c1b4fea8d dma-debug: fix a possible deadlock on radix_lock ... [ Upstream commit 7543c3e3b9 ] radix_lock() shouldn't be held while holding dma_hash_entry[idx].lock otherwise, there's a possible deadlock scenario when dma debug API is called holding rq_lock(): CPU0 CPU1 CPU2 dma_free_attrs() check_unmap() add_dma_entry() __schedule() //out (A) rq_lock() get_hash_bucket() (A) dma_entry_hash check_sync() (A) radix_lock() (W) dma_entry_hash dma_entry_free() (W) radix_lock() // CPU2's one (W) rq_lock() CPU1 situation can happen when it extending radix tree and it tries to wake up kswapd via wake_all_kswapd(). CPU2 situation can happen while perf_event_task_sched_out() (i.e. dma sync operation is called while deleting perf_event using etm and etr tmc which are Arm Coresight hwtracing driver backends). To remove this possible situation, call dma_entry_free() after put_hash_bucket() in check_unmap(). Reported-by: Denis Nikitin <denik@chromium.org> Closes: https://lists.linaro.org/archives/list/coresight@lists.linaro.org/thread/2WMS7BBSF5OZYB63VT44U5YWLFP5HL6U/#RWM6MLQX5ANBTEQ2PRM7OXCBGCE6NPWU Signed-off-by: Levi Yun <yeoreum.yun@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>		2024-12-14 19:54:43 +01:00
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coherent.c	dma-mapping: clear dev->dma_mem to NULL after freeing it	2024-01-25 15:27:28 -08:00
contiguous.c	cma: factor out minimum alignment requirement	2022-03-22 15:57:05 -07:00
debug.c	dma-debug: fix a possible deadlock on radix_lock	2024-12-14 19:54:43 +01:00
debug.h	dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC	2021-10-18 12:46:45 +02:00
direct.c	dma-direct: Leak pages on dma_set_decrypted() failure	2024-04-13 13:04:59 +02:00
direct.h	dma-direct: support PCI P2PDMA pages in dma-direct map_sg	2022-07-26 07:27:47 -04:00
dummy.c	dma-mapping: return error code from dma_dummy_map_sg()	2021-08-09 17:13:06 +02:00
Kconfig	dma-mapping: remove CONFIG_DMA_REMAP	2022-03-03 14:00:57 +03:00
Makefile	dma-mapping: remove CONFIG_DMA_REMAP	2022-03-03 14:00:57 +03:00
map_benchmark.c	dma-mapping: benchmark: Don't starve others when doing the test	2024-09-12 11:10:23 +02:00
mapping.c	dma: fix call order in dmam_free_coherent	2024-08-03 08:49:49 +02:00
ops_helpers.c	dma-mapping: handle vmalloc addresses in dma_common_{mmap,get_sgtable}	2021-07-16 11:30:26 +02:00
pool.c	dma/pool: create dma atomic pool only if dma zone has managed pages	2022-01-15 16:30:29 +02:00
remap.c	dma-remap: use kvmalloc_array/kvfree for larger dma memory remap	2023-08-23 17:52:21 +02:00
swiotlb.c	swiotlb: Fix alignment checks when both allocation and DMA masks are present	2024-04-03 15:19:44 +02:00