Re: [PATCH 2/2] coresight: trbe: Allocate platform data per device

From: Anshuman Khandual
Date: Thu Aug 17 2023 - 02:37:58 EST


Hi Suzuki,

Seems like this patch is going to conflict with the below proposed change

https://lore.kernel.org/all/20230817055405.249630-4-anshuman.khandual@xxxxxxx/

Please let me know how should we resolve this conflict.

On 8/16/23 19:40, Suzuki K Poulose wrote:
> Coresight TRBE driver shares a single platform data (which is empty btw).
> However, with the commit 4e8fe7e5c3a5
> ("coresight: Store pointers to connections rather than an array of them")
> the coresight core would free up the pdata, resulting in multiple attempts
> to free the same pdata for TRBE instances. Fix this by allocating a pdata per
> coresight_device.
>
> Fixes: 3fbf7f011f24 ("coresight: sink: Add TRBE driver")

The above mentioned commit i.e 4e8fe7e5c3a5 seems to be a more recent one which
has triggered this problem. But would the problem be still there without that ?
Else 'Fixes:' tag would need changing.

> Link: https://lore.kernel.org/r/20230814093813.19152-3-hejunhao3@xxxxxxxxxx
> Reported-by: Junhao He <hejunhao3@xxxxxxxxxx>
> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> ---
> drivers/hwtracing/coresight/coresight-trbe.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
> index 025f70adee47..d3d34a833f01 100644
> --- a/drivers/hwtracing/coresight/coresight-trbe.c
> +++ b/drivers/hwtracing/coresight/coresight-trbe.c
> @@ -1255,10 +1255,13 @@ static void arm_trbe_register_coresight_cpu(struct trbe_drvdata *drvdata, int cp
> if (!desc.name)
> goto cpu_clear;
>
> + desc.pdata = coresight_get_platform_data(dev);
> + if (IS_ERR(desc.pdata))
> + goto cpu_clear;
> +
> desc.type = CORESIGHT_DEV_TYPE_SINK;
> desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_PERCPU_SYSMEM;
> desc.ops = &arm_trbe_cs_ops;
> - desc.pdata = dev_get_platdata(dev);
> desc.groups = arm_trbe_groups;
> desc.dev = dev;
> trbe_csdev = coresight_register(&desc);
> @@ -1482,7 +1485,6 @@ static void arm_trbe_remove_irq(struct trbe_drvdata *drvdata)
>
> static int arm_trbe_device_probe(struct platform_device *pdev)
> {
> - struct coresight_platform_data *pdata;
> struct trbe_drvdata *drvdata;
> struct device *dev = &pdev->dev;
> int ret;
> @@ -1497,12 +1499,7 @@ static int arm_trbe_device_probe(struct platform_device *pdev)
> if (!drvdata)
> return -ENOMEM;
>
> - pdata = coresight_get_platform_data(dev);
> - if (IS_ERR(pdata))
> - return PTR_ERR(pdata);
> -
> dev_set_drvdata(dev, drvdata);
> - dev->platform_data = pdata;
> drvdata->pdev = pdev;
> ret = arm_trbe_probe_irq(pdev, drvdata);
> if (ret)