Requests the vchan lock before using xdma->stop_request.
Fixes: 6a40fb824596 ("dmaengine: xilinx: xdma: Fix synchronization issue")
Cc: [email protected]
Signed-off-by: Louis Chauvet <[email protected]>
---
Changes in v2:
- Apply comments from Markus
- Link to v1: https://lore.kernel.org/r/[email protected]
---
drivers/dma/xilinx/xdma.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/xilinx/xdma.c b/drivers/dma/xilinx/xdma.c
index e143a7330816..718842fdaf98 100644
--- a/drivers/dma/xilinx/xdma.c
+++ b/drivers/dma/xilinx/xdma.c
@@ -885,11 +885,11 @@ static irqreturn_t xdma_channel_isr(int irq, void *dev_id)
u32 st;
bool repeat_tx;
+ spin_lock(&xchan->vchan.lock);
+
if (xchan->stop_requested)
complete(&xchan->last_interrupt);
- spin_lock(&xchan->vchan.lock);
-
/* get submitted request */
vd = vchan_next_desc(&xchan->vchan);
if (!vd)
---
base-commit: 1613e604df0cd359cf2a7fbd9be7a0bcfacfabd0
change-id: 20240527-xdma-fixes-74bbe2dcbeb8
Best regards,
--
Louis Chauvet <[email protected]>
> Requests the vchan lock before using xdma->stop_request.
Better wording alternative?:
A data synchronisation construct was missing in this function implementation.
Thus apply the vchan lock before checking the data structure
member “xchan->stop_requested”.
> ---
> drivers/dma/xilinx/xdma.c | 4 ++--
How do think about to avoid a duplicate marker line?
…
> +++ b/drivers/dma/xilinx/xdma.c
> @@ -885,11 +885,11 @@ static irqreturn_t xdma_channel_isr(int irq, void *dev_id)
> u32 st;
> bool repeat_tx;
>
> + spin_lock(&xchan->vchan.lock);
> +
> if (xchan->stop_requested)
> complete(&xchan->last_interrupt);
>
> - spin_lock(&xchan->vchan.lock);
> -
> /* get submitted request */
…
Under which circumstances will development interests grow for the usage of
a statement like “guard(raw_spinlock)(&xchan->vchan.lock);”?
https://elixir.bootlin.com/linux/v6.10-rc2/source/include/linux/cleanup.h#L124
Regards,
Markus
…
> +++ b/drivers/dma/xilinx/xdma.c
> @@ -885,11 +885,11 @@ static irqreturn_t xdma_channel_isr(int irq, void *dev_id)
> u32 st;
> bool repeat_tx;
>
> + spin_lock(&xchan->vchan.lock);
> +
> if (xchan->stop_requested)
> complete(&xchan->last_interrupt);
…
Can any lock scope adjustments matter also for another variable definition?
https://elixir.bootlin.com/linux/v6.10-rc2/source/drivers/dma/xilinx/xdma.c#L873
struct xdma_device *xdev = xchan->xdev_hdl;
Regards,
Markus
On Fri, 07 Jun 2024 10:34:38 +0200, Louis Chauvet wrote:
> Requests the vchan lock before using xdma->stop_request.
>
>
Applied, thanks!
[1/1] dmaengine: xilinx: xdma: Fix data synchronisation in xdma_channel_isr()
commit: 462237d2d93fc9e9221d1cf9f773954d27da83c0
Best regards,
--
Vinod Koul <[email protected]>