Re: [PATCH net v4] batman-adv: Fix double-hold of meshif when getting enabled
From: Simon Horman
Date: Mon Apr 14 2025 - 12:55:39 EST
On Thu, Apr 10, 2025 at 08:58:51PM +0200, Sven Eckelmann wrote:
> It was originally meant to replace the dev_hold with netdev_hold. But this
> was missed in batadv_hardif_enable_interface(). As result, there was an
> imbalance and a hang when trying to remove the mesh-interface with
> (previously) active hard-interfaces:
>
> unregister_netdevice: waiting for batadv0 to become free. Usage count = 3
>
> Fixes: 00b35530811f ("batman-adv: adopt netdev_hold() / netdev_put()")
> Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx>
> ---
> This patch is skipping Simon's normal PR submission to get this problem
> fixed faster in Linus' tree. This currently creates quite a lot of wrong
> bisect results for syzkaller and it would be better to have this fixed
> sooner than later.
> ---
> Changes in v4:
> - added Suggested-by: Eric Dumazet <edumazet@xxxxxxxxxx>
> - added Reported-by: of various syzkaller reports which were affected (during
> bisecting) by this problem
FWIIW, I don't see those tags at the bottom of the commit message.
> - resubmission after 24h cooldown time
> - added kernel message during hang to commit message
> - Link to v3: https://lore.kernel.org/r/20250409073524.557189-1-sven@xxxxxxxxxxxxx
> Changes in v3:
> - fix submitter address
> - Link to v2: https://lore.kernel.org/r/20250409073304.556841-1-sw@xxxxxxxxxxxxxxxxxx
> Changes in v2:
> - add missing commit message
> - Link to v1: https://lore.kernel.org/r/20250409073000.556263-1-sven@xxxxxxxxxxxxx
...