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From: Krzysztof Kozlowski <krzk@kernel.org>
To: Johan Hovold <johan@kernel.org>,
	Guangshuo Li <lgs201920130244@gmail.com>
Cc: Vinod Koul <vkoul@kernel.org>, Frank Li <Frank.Li@kernel.org>,
	Russell King <rmk+kernel@arm.linux.org.uk>,
	Ulf Hansson <ulfh@kernel.org>,
	dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Subject: Re: [PATCH] dmaengine: pl330: fix autosuspend cleanup during removal
Date: Tue, 18 Aug 2026 10:42:40 +0200	[thread overview]
Message-ID: <8a4dd0ef-79ec-4295-9f01-24239edf99cf@kernel.org> (raw)
In-Reply-To: <aoQZX1h-9vobiHev@hovoldconsulting.com>

On 18/08/2026 10:35, Johan Hovold wrote:
> On Sat, Aug 08, 2026 at 05:44:52PM +0800, Guangshuo Li wrote:
>> pl330_probe() calls pm_runtime_use_autosuspend(), but pl330_remove()
>> does not call the matching pm_runtime_dont_use_autosuspend() when
>> removing the device.
>>
>> If the autosuspend delay is set to a negative value while autosuspend
>> is enabled, the runtime PM core increments usage_count to prevent
>> runtime suspend. Without calling pm_runtime_dont_use_autosuspend()
>> during teardown, this reference is not dropped and usage_count remains
>> unbalanced.
> 
> As I've explained elsewhere, this is just misleading. There is no usage
> count leak here as the count is balanced whenever the user re-enables
> autosuspend through sysfs (by writing a non-negative timeout).
> 
> Drivers should clean up after themselves and disable autosuspend, but
> this is more of a clean up than a fix and should not be backported.
> 
> You've sent upwards of 60 of these in the matter of a just a few days,
> some which have even been picked up. Please send follow-ups (replies or
> v2s) as soon as possible to prevent further of these from getting
> merged.
> 
>> Add the missing pm_runtime_dont_use_autosuspend() call before restoring
>> the runtime PM usage reference in the remove path.
>>
>> This issue was found by manual code inspection.
>>
>> Fixes: ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>


So EVERY patch was sent separately, even when targeting the same subsystem:
https://lore.kernel.org/all/?q=f%3Algs201920130244%40gmail.com

making it IMPOSSIBLE to respond in efficient way. This is just unacceptable.

Best regards,
Krzysztof

      reply	other threads:[~2026-08-18  8:43 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-08  9:44 [PATCH] dmaengine: pl330: fix autosuspend cleanup during removal Guangshuo Li
2026-08-08 10:03 ` sashiko-bot
2026-08-18  8:35 ` Johan Hovold
2026-08-18  8:42   ` Krzysztof Kozlowski [this message]

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