diff mbox series

[v2,1/1] mmc: host: meson-gx-mmc: fix possible deadlock condition for preempt_rt

Message ID 20200927025418.12382-2-bjharper@gmail.com
State New
Headers show
Series mmc: host: meson-gx-mmc: fix possible deadlock condition for preempt_rt | expand

Commit Message

Brad Harper Sept. 27, 2020, 2:54 a.m. UTC
---
 drivers/mmc/host/meson-gx-mmc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Sebastian Andrzej Siewior Sept. 28, 2020, 4:41 p.m. UTC | #1
On 2020-09-26 22:54:18 [-0400], Brad Harper wrote:
> ---

What happens if you boot this on a non-RT kernel with the `threadirqs'
command line option?

Sebastian
Brad Harper Sept. 29, 2020, 8:32 a.m. UTC | #2
Hi Kevin,

     I think you are right,  I don't have a good enough understanding to 
make this work so please disregard the patch.  I will take on 
Sebastian's advice and do some testing with 'threadirqs' parameter 
enabled in standard kernel to see if I can reproduce my original issue 
there.  I'm hoping Jerome might also be able to help with some time to 
find proper solution.

Many Thanks,

Brad.

On 29/09/2020 10:35 am, Kevin Hilman wrote:
> Brad Harper <bjharper@gmail.com> writes:
>
>> ---
>>   drivers/mmc/host/meson-gx-mmc.c | 4 +++-
>>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> This patch still needs changelog summarizing the problem and what is
> being fixed by the patch.  Most of what's in the cover letter belongs
> here.
>
> The cover letter can be used to describe the history/background that you
> don't want in the patch itself.  Alternatviely, you could include that
> information in the a single patch email also because everything after
> the "---" line does not end up in git history.
>
>> diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
>> index 08a3b1c05..3ba8f988d 100644
>> --- a/drivers/mmc/host/meson-gx-mmc.c
>> +++ b/drivers/mmc/host/meson-gx-mmc.c
>> @@ -146,6 +146,7 @@ struct sd_emmc_desc {
>>   };
>>   
>>   struct meson_host {
>> +	spinlock_t		lock;
>>   	struct	device		*dev;
>>   	struct	meson_mmc_data *data;
>>   	struct	mmc_host	*mmc;
>> @@ -1051,6 +1052,7 @@ static int meson_mmc_probe(struct platform_device *pdev)
>>   	host->mmc = mmc;
>>   	host->dev = &pdev->dev;
>>   	dev_set_drvdata(&pdev->dev, host);
>> +	spin_lock_init(&host->lock);
> I'm confused about what this lock is intended to do.  You init it here,
> but it's never used anywhere.
>
>>   	/* The G12A SDIO Controller needs an SRAM bounce buffer */
>>   	host->dram_access_quirk = device_property_read_bool(&pdev->dev,
>> @@ -1139,7 +1141,7 @@ static int meson_mmc_probe(struct platform_device *pdev)
>>   	       host->regs + SD_EMMC_IRQ_EN);
>>   
>>   	ret = request_threaded_irq(host->irq, meson_mmc_irq,
>> -				   meson_mmc_irq_thread, IRQF_ONESHOT,
>> +				   meson_mmc_irq_thread, 0,
>>   				   dev_name(&pdev->dev), host);
>>   	if (ret)
>>   		goto err_init_clk;
> Kevin
diff mbox series

Patch

diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index 08a3b1c05..3ba8f988d 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -146,6 +146,7 @@  struct sd_emmc_desc {
 };
 
 struct meson_host {
+	spinlock_t		lock;
 	struct	device		*dev;
 	struct	meson_mmc_data *data;
 	struct	mmc_host	*mmc;
@@ -1051,6 +1052,7 @@  static int meson_mmc_probe(struct platform_device *pdev)
 	host->mmc = mmc;
 	host->dev = &pdev->dev;
 	dev_set_drvdata(&pdev->dev, host);
+	spin_lock_init(&host->lock);
 
 	/* The G12A SDIO Controller needs an SRAM bounce buffer */
 	host->dram_access_quirk = device_property_read_bool(&pdev->dev,
@@ -1139,7 +1141,7 @@  static int meson_mmc_probe(struct platform_device *pdev)
 	       host->regs + SD_EMMC_IRQ_EN);
 
 	ret = request_threaded_irq(host->irq, meson_mmc_irq,
-				   meson_mmc_irq_thread, IRQF_ONESHOT,
+				   meson_mmc_irq_thread, 0,
 				   dev_name(&pdev->dev), host);
 	if (ret)
 		goto err_init_clk;