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Date: Wed, 26 Nov 2025 10:40:34 -0800
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Subject: Re: [PATCH 1/2] PM: runtime: Fix I/O hang due to race between resume
 and runtime disable
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: YangYang <yang.yang@vivo.com>, Jens Axboe <axboe@kernel.dk>,
 Pavel Machek <pavel@kernel.org>, Len Brown <lenb@kernel.org>,
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From: Bart Van Assche <bvanassche@acm.org>
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On 11/26/25 7:41 AM, Rafael J. Wysocki wrote:
> As it stands, you have a basic problem with respect to system
> suspend/hibernation.  As I said before, the PM workqueue is frozen
> during system suspend/hibernation transitions, so waiting for an async
> resume request to complete then is pointless.

Agreed. I noticed that any attempt to call request_firmware() from
driver system resume callback functions causes a deadlock if these
calls happen before the block device has been resumed.

Thanks,

Bart.