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Message-ID: <5b555935-5657-3f38-8a55-906dd32ad052@samsung.com>
Date:   Fri, 24 Mar 2023 14:28:57 +0100
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Subject: Re: [PATCH] mmc: core: remove unnecessary (void*) conversions
Content-Language: en-US
To:     Yu Zhe <yuzhe@nfschina.com>, ulf.hansson@linaro.org
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org, liqiong@nfschina.com
From:   Marek Szyprowski <m.szyprowski@samsung.com>
In-Reply-To: <20230317064729.24407-1-yuzhe@nfschina.com>
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References: <20230317064729.24407-1-yuzhe@nfschina.com>
        <CGME20230324132858eucas1p25cdd6af81a14bf40474f58fa16d087f5@eucas1p2.samsung.com>
Precedence: bulk

On 17.03.2023 07:47, Yu Zhe wrote:
> Pointer variables of void * type do not require type cast.
>
> Signed-off-by: Yu Zhe <yuzhe@nfschina.com>
> ---
>   drivers/mmc/core/debugfs.c  | 2 +-
>   drivers/mmc/core/host.c     | 2 +-
>   drivers/mmc/core/mmc_test.c | 6 +++---
>   3 files changed, 5 insertions(+), 5 deletions(-)
...
> diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
> index 096093f7be00..76900f67c782 100644
> --- a/drivers/mmc/core/host.c
> +++ b/drivers/mmc/core/host.c
> @@ -590,7 +590,7 @@ EXPORT_SYMBOL(mmc_alloc_host);
>   
>   static void devm_mmc_host_release(struct device *dev, void *res)
>   {
> -	mmc_free_host(*(struct mmc_host **)res);
> +	mmc_free_host(res);

The above chunk is wrong and causes following regression on today's 
Linux next-20230324:

Unable to handle kernel paging request at virtual address 0000000000001020
Mem abort info:
meson-gx-mmc ffe07000.mmc: allocated mmc-pwrseq
...
[0000000000001020] user address but active_mm is swapper
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 3 PID: 10 Comm: kworker/u12:0 Not tainted 6.3.0-rc3-next-20230324+ 
#13452
Hardware name: Khadas VIM3 (DT)
Workqueue: events_unbound async_run_entry_fn
pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : mmc_pwrseq_free+0x1c/0x38
lr : devm_mmc_host_release+0x1c/0x34
...
Call trace:
  mmc_pwrseq_free+0x1c/0x38
  devm_mmc_host_release+0x1c/0x34
  release_nodes+0x5c/0x90
  devres_release_all+0x8c/0xdc
  device_unbind_cleanup+0x18/0x68
  really_probe+0x11c/0x2b4
  __driver_probe_device+0x78/0xe0
  driver_probe_device+0xd8/0x160
  __device_attach_driver+0xb8/0x138
  bus_for_each_drv+0x84/0xe0
  __device_attach_async_helper+0xb0/0xd4
  async_run_entry_fn+0x34/0xe0
  process_one_work+0x288/0x5c0
  worker_thread+0x74/0x450
  kthread+0x124/0x128
  ret_from_fork+0x10/0x20
Code: f9000bf3 aa0003f3 f9424c00 b4000080 (f9401000)
---[ end trace 0000000000000000 ]---

Ulf: do You want me to send a partial revert or will you handle it by 
dropping this patch?

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland