Re: [PATCH] devcoredump: Send uevent once devcd is ready

From: Johannes Berg
Date: Mon Nov 06 2023 - 14:39:20 EST


On Mon, 2023-11-06 at 20:36 +0100, Greg KH wrote:
> On Mon, Nov 06, 2023 at 07:55:35PM +0530, Mukesh Ojha wrote:
> > dev_coredumpm() creates a devcoredump device and adds it
> > to the core kernel framework which eventually end up
> > sending uevent to the user space and later creates a
> > symbolic link to the failed device. An application
> > running in userspace may be interested in this symbolic
> > link to get the name of the failed device.
> >
> > In a issue scenario, once uevent sent to the user space
> > it start reading '/sys/class/devcoredump/devcdX/failing_device'
> > to get the actual name of the device which might not been
> > created and it is in its path of creation.
> >
> > To fix this, suppress sending uevent till the failing device
> > symbolic link gets created and send uevent once symbolic
> > link is created successfully.
> >
> > Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
>
> What commit id does this fix? 
>

I guess the original introduction.

> What in-kernel driver does this affect
> that is using devcoredump?
>

All of them really, it's really about how fast userspace is to access it
after the event.

Looks fine to me, FWIW, but a Fixes tag wouldn't hurt.

johannes