This is a note to let you know that I've just added the patch titled
spi: atmel: fixed spin_lock usage inside atmel_spi_remove
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
spi-atmel-fixed-spin_lock-usage-inside-atmel_spi_remove.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Wed Feb 28 16:19:30 CET 2018
From: Radu Pirea <radu.pirea@xxxxxxxxxxxxx>
Date: Fri, 15 Dec 2017 17:40:17 +0200
Subject: spi: atmel: fixed spin_lock usage inside atmel_spi_remove
From: Radu Pirea <radu.pirea@xxxxxxxxxxxxx>
[ Upstream commit 66e900a3d225575c8b48b59ae1fe74bb6e5a65cc ]
The only part of atmel_spi_remove which needs to be atomic is hardware
reset.
atmel_spi_stop_dma calls dma_terminate_all and this needs interrupts
enabled.
atmel_spi_release_dma calls dma_release_channel and dma_release_channel
locks a mutex inside of spin_lock.
So the call of these functions can't be inside a spin_lock.
Reported-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
Signed-off-by: Radu Pirea <radu.pirea@xxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/spi/spi-atmel.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1669,12 +1669,12 @@ static int atmel_spi_remove(struct platf
pm_runtime_get_sync(&pdev->dev);
/* reset the hardware and block queue progress */
- spin_lock_irq(&as->lock);
if (as->use_dma) {
atmel_spi_stop_dma(as);
atmel_spi_release_dma(as);
}
+ spin_lock_irq(&as->lock);
spi_writel(as, CR, SPI_BIT(SWRST));
spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
spi_readl(as, SR);
Patches currently in stable-queue which might be from radu.pirea@xxxxxxxxxxxxx are
queue-4.4/spi-atmel-fixed-spin_lock-usage-inside-atmel_spi_remove.patch