dma-mapping: clear dev->dma_mem to NULL after freeing it

[ 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: cf65a0f6f6 ("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>
This commit is contained in:
Joakim Zhang 2023-12-14 16:25:26 +08:00 committed by Greg Kroah-Hartman
parent 542da27eac
commit aaf0fc13be
1 changed files with 3 additions and 1 deletions

View File

@ -132,8 +132,10 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
void dma_release_coherent_memory(struct device *dev)
{
if (dev)
if (dev) {
_dma_release_coherent_memory(dev->dma_mem);
dev->dma_mem = NULL;
}
}
static void *__dma_alloc_from_coherent(struct device *dev,