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Date: Wed, 29 May 2024 16:43:51 +0300
From: Vladimir Oltean <olteanv@gmail.com>
To: Radoslaw Zielonek <radoslaw.zielonek@gmail.com>
Cc: vladimir.oltean@nxp.com, davem@davemloft.net, edumazet@google.com,
	kuba@kernel.org, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, pabeni@redhat.com,
	syzbot+a7d2b1d5d1af83035567@syzkaller.appspotmail.com,
	syzkaller-bugs@googlegroups.com, vinicius.gomes@intel.com,
	willemdebruijn.kernel@gmail.com
Subject: Re: [syzbot] [net?] INFO: rcu detected stall in packet_release
Message-ID: <20240529134351.vtrh4oohb7g274ej@skbuf>
References: <20240528125526.qwskv756uya3zaqb@skbuf>
 <20240528130331.21904-2-radoslaw.zielonek@gmail.com>
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In-Reply-To: <20240528130331.21904-2-radoslaw.zielonek@gmail.com>

On Tue, May 28, 2024 at 03:03:25PM +0200, Radoslaw Zielonek wrote:
> Hello,
> 
> Ah, sorry. I didn't notice that.
> The PoC has been tested by syzbot
> 	[https://syzkaller.appspot.com/bug?extid=c4c6c3dc10cc96bcf723]
> 	
> The full link:
> 	[https://lore.kernel.org/all/00000000000089427c0614c18cf4@google.com/T/]
> 
> Radosław.
> 
> 

The patch, in the form you are presenting, obviously derails the phase
alignment of the new schedule when the core struggles to keep up with
the hrtimer. I am not in favor of adding any logic to taprio that
instructs it to behave out of spec.