Re: [PATCH v5 2/9] ALSA: virtio: add virtio sound driver
From: Takashi Iwai
Date: Thu Feb 25 2021 - 07:08:53 EST
On 2021年2月25日 12:51:36 +0100,
Anton Yakovlev wrote:
>
>
> Now I'm wondering whether it's safe to do that from this place.
>
> Basically device_reprobe() unbinds the device that releases the full
>
> resources once including the devm_* stuff. And this work itself is in
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> a part of devm allocated resource, so it'll be released there. That
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> said, we might hit use-after-free... This needs to be verified.
>
>
It's safe. Suicide kernel workers are funny but possible things. Since
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the kernel itself (AFAIU) assumes such a situation and does not access
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the worker structure after the callback function call.
Indeed, process_one_work() in workqueue.c assures no access to the
work object after the callback. Then this must be fine. Good to
know!
thanks,
Takashi