mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-07 13:57:54 -04:00
Code Issues Packages Projects Releases Wiki Activity

dmaengine: imx-sdma: fix cyclic buffer race condition

Browse Source 
Assign buffer ownership to SDMA after invoking descriptor callback to
make sure that SDMA does not write to the buffer before it is read by
the CPU.

Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220117091955.1038937-2-tomasz.mon@camlingroup.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Tomasz Moń
2022-01-17 10:19:55 +01:00
committed by Vinod Koul
parent 5b215c28b9
commit 177360e04b
1 changed files with 3 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/dma/imx-sdma.c
View File

@@ -847,7 +847,6 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
*/
desc->chn_real_count = bd->mode.count;
bd->mode.status |= BD_DONE;
bd->mode.count = desc->period_len;
desc->buf_ptail = desc->buf_tail;
desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd;
@@ -862,6 +861,9 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
dmaengine_desc_get_callback_invoke(&desc->vd.tx, NULL);
spin_lock(&sdmac->vc.lock);
/* Assign buffer ownership to SDMA */
bd->mode.status |= BD_DONE;
if (error)
sdmac->status = old_status;
}