Re: [PATCH] common/rc: add default _udev_wait timeout

["Darrick J. Wong" <djwong@kernel.org>]

On Thu, Mar 19, 2026 at 11:51:54AM +1100, David Disseldorp wrote:
> If udevd isn't running then "udevadm wait" loops endlessly. With a
> --timeout parameter provided, udevadm (udev-254.27) prints to stderr:
>   Timed out for waiting devices being initialized.

If you don't have udevd running, then perhaps we should detect that and
directly call "sleep 10"?  Because otherwise...

> The error message causes test failure via golden output mismatch and
> is easier to debug than an infinite loop.
> 
> The timeout parameter is also compatible with existing
> args="--removed <dev>" callers.
> 
> Signed-off-by: David Disseldorp <ddiss@suse.de>
> ---
>  common/rc | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/common/rc b/common/rc
> index fd4ca964..aade0e5b 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -5544,7 +5544,7 @@ _udev_wait()
>  	if [ -z "$UDEV_WAIT_PROG" ]; then
>  		$UDEV_SETTLE_PROG >/dev/null 2>&1
>  	else
> -		$UDEV_WAIT_PROG $args
> +		$UDEV_WAIT_PROG --timeout 10 $args

...a system running udevd that's taking forever to process rules can hit
this 10 second timeout, at which point the test moves on and might just
fail due to unconfigured /dev nodes.

/methinks this could be done like so:

	if [ ! -S /run/udev/control ]; then
		sleep 10
	elif [ -z "$UDEV_WAIT_PROG" ]; then
		...

I don't know if your test setup has prepopulated /dev or if you've a
script that sets up devices, or something else.  10 seconds is just a
copy-paste.

--D

>  	fi
>  }
>  
> -- 
> 2.51.0
> 
>