linux-stable.git/kernel/dma/coherent.c, branch v4.19.321 Linux kernel stable tree dma-mapping: clear dev->dma_mem to NULL after freeing it 2024-01-25T22:33:34+00:00 Joakim Zhang joakim.zhang@cixtech.com 2023-12-14T08:25:26+00:00 5ef6f81c326a1c0c7799a823a5510b74f958ac32 [ Upstream commit b07bc2347672cc8c7293c64499f1488278c5ca3d ] Reproduced with below sequence: dma_declare_coherent_memory()->dma_release_coherent_memory() ->dma_declare_coherent_memory()->"return -EBUSY" error It will return -EBUSY from the dma_assign_coherent_memory() in dma_declare_coherent_memory(), the reason is that dev->dma_mem pointer has not been set to NULL after it's freed. Fixes: cf65a0f6f6ff ("dma-mapping: move all DMA mapping code to kernel/dma") Signed-off-by: Joakim Zhang <joakim.zhang@cixtech.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit b07bc2347672cc8c7293c64499f1488278c5ca3d ]

Reproduced with below sequence:
dma_declare_coherent_memory()->dma_release_coherent_memory()
->dma_declare_coherent_memory()->"return -EBUSY" error

It will return -EBUSY from the dma_assign_coherent_memory()
in dma_declare_coherent_memory(), the reason is that dev->dma_mem
pointer has not been set to NULL after it's freed.

Fixes: cf65a0f6f6ff ("dma-mapping: move all DMA mapping code to kernel/dma")
Signed-off-by: Joakim Zhang <joakim.zhang@cixtech.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dma-mapping: move all DMA mapping code to kernel/dma 2018-06-14T06:50:37+00:00 Christoph Hellwig hch@lst.de 2018-06-12T17:01:45+00:00 cf65a0f6f6ff7631ba0ac0513a14ca5b65320d80 Currently the code is split over various files with dma- prefixes in the lib/ and drives/base directories, and the number of files keeps growing. Move them into a single directory to keep the code together and remove the file name prefixes. To match the irq infrastructure this directory is placed under the kernel/ directory. Signed-off-by: Christoph Hellwig <hch@lst.de> 
Currently the code is split over various files with dma- prefixes in the
lib/ and drives/base directories, and the number of files keeps growing.
Move them into a single directory to keep the code together and remove
the file name prefixes.  To match the irq infrastructure this directory
is placed under the kernel/ directory.

Signed-off-by: Christoph Hellwig <hch@lst.de>