netdev - Re: [PATCH net] net: drv: netdevsim: don't napi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aEqVefLEgSz9AzHG@gmail.com>
Date: Thu, 12 Jun 2025 01:53:13 -0700
From: Breno Leitao <leitao@...ian.org>
To: Jakub Kicinski <kuba@...nel.org>
Cc: davem@...emloft.net, netdev@...r.kernel.org, edumazet@...gle.com,
	pabeni@...hat.com, andrew+netdev@...n.ch, horms@...nel.org,
	dw@...idwei.uk
Subject: Re: [PATCH net] net: drv: netdevsim: don't napi_complete() from
 netpoll

Hello Jakub,

On Wed, Jun 11, 2025 at 10:46:43AM -0700, Jakub Kicinski wrote:
> netdevsim supports netpoll. Make sure we don't call napi_complete()
> from it, since it may not be scheduled. Breno reports hitting a
> warning in napi_complete_done():
> 
> WARNING: CPU: 14 PID: 104 at net/core/dev.c:6592 napi_complete_done+0x2cc/0x560
>   __napi_poll+0x2d8/0x3a0
>   handle_softirqs+0x1fe/0x710
> 
> This is presumably after netpoll stole the SCHED bit prematurely.
> 
> Reported-by: Breno Leitao <leitao@...ian.org>
> Fixes: 3762ec05a9fb ("netdevsim: add NAPI support")
> Signed-off-by: Jakub Kicinski <kuba@...nel.org>

Tested-by: Breno Leitao <leitao@...ian.org>

Thanks for the quick fix,
--breno