From: Patrice Chotard <[email protected]>
Some device driver need to communicate to qspi device during the remove
process, qspi controller must be functional when spi_unregister_master()
is called.
To ensure this, replace devm_spi_register_master() by spi_register_master()
and spi_unregister_master() is called directly in .remove callback before
stopping the qspi controller.
This issue was put in evidence using kernel v5.11 and later
with a spi-nor which supports the software reset feature introduced
by commit d73ee7534cc5 ("mtd: spi-nor: core: perform a Soft Reset on
shutdown")
Fixes: c530cd1d9d5e ("spi: spi-mem: add stm32 qspi controller")
Signed-off-by: Patrice Chotard <[email protected]>
Cc: <[email protected]> # 5.8.x
---
v2:
_ update commit message
_ make usage of devm_spi_alloc_master() instead of spi_alloc_master()
drivers/spi/spi-stm32-qspi.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
index 514337c86d2c..09839a3dbb26 100644
--- a/drivers/spi/spi-stm32-qspi.c
+++ b/drivers/spi/spi-stm32-qspi.c
@@ -688,7 +688,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
struct resource *res;
int ret, irq;
- ctrl = spi_alloc_master(dev, sizeof(*qspi));
+ ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
if (!ctrl)
return -ENOMEM;
@@ -784,7 +784,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
pm_runtime_enable(dev);
pm_runtime_get_noresume(dev);
- ret = devm_spi_register_master(dev, ctrl);
+ ret = spi_register_master(ctrl);
if (ret)
goto err_pm_runtime_free;
@@ -817,6 +817,7 @@ static int stm32_qspi_remove(struct platform_device *pdev)
struct stm32_qspi *qspi = platform_get_drvdata(pdev);
pm_runtime_get_sync(qspi->dev);
+ spi_unregister_master(qspi->ctrl);
/* disable qspi */
writel_relaxed(0, qspi->io_base + QSPI_CR);
stm32_qspi_dma_free(qspi);
--
2.17.1
On Wed, Jan 12, 2022 at 03:44:24PM +0100, [email protected] wrote:
> diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
> index 514337c86d2c..09839a3dbb26 100644
> --- a/drivers/spi/spi-stm32-qspi.c
> +++ b/drivers/spi/spi-stm32-qspi.c
> @@ -688,7 +688,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
> struct resource *res;
> int ret, irq;
>
> - ctrl = spi_alloc_master(dev, sizeof(*qspi));
> + ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
> if (!ctrl)
> return -ENOMEM;
>
> @@ -784,7 +784,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
> pm_runtime_enable(dev);
> pm_runtime_get_noresume(dev);
>
> - ret = devm_spi_register_master(dev, ctrl);
> + ret = spi_register_master(ctrl);
> if (ret)
> goto err_pm_runtime_free;
>
Unfortunately this patch is still not correct: It introduces a
double free in the probe error path.
You need to remove this...
err_master_put:
spi_master_put(qspi->ctrl);
...and replace all the gotos in stm32_qspi_probe() which jump
to the err_master_put label with a return statement.
Thanks,
Lukas
Hi Lukas
On 1/16/22 1:52 PM, Lukas Wunner wrote:
> On Wed, Jan 12, 2022 at 03:44:24PM +0100, [email protected] wrote:
>> diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
>> index 514337c86d2c..09839a3dbb26 100644
>> --- a/drivers/spi/spi-stm32-qspi.c
>> +++ b/drivers/spi/spi-stm32-qspi.c
>> @@ -688,7 +688,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
>> struct resource *res;
>> int ret, irq;
>>
>> - ctrl = spi_alloc_master(dev, sizeof(*qspi));
>> + ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
>> if (!ctrl)
>> return -ENOMEM;
>>
>> @@ -784,7 +784,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
>> pm_runtime_enable(dev);
>> pm_runtime_get_noresume(dev);
>>
>> - ret = devm_spi_register_master(dev, ctrl);
>> + ret = spi_register_master(ctrl);
>> if (ret)
>> goto err_pm_runtime_free;
>>
>
> Unfortunately this patch is still not correct: It introduces a
> double free in the probe error path.
Argh yes, my bad.
>
> You need to remove this...
>
> err_master_put:
> spi_master_put(qspi->ctrl);
>
> ...and replace all the gotos in stm32_qspi_probe() which jump
> to the err_master_put label with a return statement.
>
> Thanks,
>
> Lukas
>
Thanks
Patrice