netdev - Re: [PATCH net v2] net: airoha: Fix schedule while atomic in airoha_ppe

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 for Android: free password hash cracker in your pocket

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

Message-ID: <aWZIGbwN1fdHCgnb@horms.kernel.org>
Date: Tue, 13 Jan 2026 13:26:49 +0000
From: Simon Horman <horms@...nel.org>
To: Lorenzo Bianconi <lorenzo@...nel.org>
Cc: Andrew Lunn <andrew+netdev@...n.ch>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org, netdev@...r.kernel.org
Subject: Re: [PATCH net v2] net: airoha: Fix schedule while atomic in
 airoha_ppe_deinit()

On Fri, Jan 09, 2026 at 10:33:55AM +0100, Lorenzo Bianconi wrote:
> > On Mon, Jan 05, 2026 at 09:43:31AM +0100, Lorenzo Bianconi wrote:
> > > airoha_ppe_deinit() runs airoha_npu_ppe_deinit() in atomic context.
> > > airoha_npu_ppe_deinit routine allocates ppe_data buffer with GFP_KERNEL
> > > flag. Rely on rcu_replace_pointer in airoha_ppe_deinit routine in order
> > > to fix schedule while atomic issue in airoha_npu_ppe_deinit() since we
> > > do not need atomic context there.
> > 
> > Hi Lorenzo,
> 
> Hi Simon,
> 
> > 
> > If I understand things correctly the key problem here is that
> > an allocation with GFP_KERNEL implies GFP_RECLAIM and thus may sleep.
> > But RCU read-side critical sections are not allowed to sleep in non-RT
> > kernels.
> 
> yes, right, RCU section is atomic.
> 
> > 
> > If so, I think it would be clearer to describe the problem along those
> > lines. But maybe it is just me.
> 
> This patch is already in Linus's tree.

Yeah, sorry for missing that.