From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9120AEC2; Thu, 12 Jun 2025 11:37:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749728271; cv=none; b=hpnjNZtSL+dD+NklP9VWjGpAM57H8odvCMHAigv1FwtGJNhwMry3LdwzL7mz/+V9ohQkV3qjN6VWF1uM+B9j0B+ZIfdWrrM4A0r27lRFrPdrIjZUPG1bH3sB0Ego85Vs5fQ51C7qDJ3Aq/OkKYV3gJu4TQguOdmIm23n1tvoIH8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749728271; c=relaxed/simple; bh=RC6e67q4bD7RzUdBsPC19A7/O1+Ylly3nWUTzq8H6C0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=usGvXV6dmIgCuiYWR78MlC1fV5ADpotvMBAq788jkm6nqOhPoCewFMU/8D5V6vifaz05xJOTulXBnLddjnDCL4v4Bhzr07fZk9a7Pja/h2pWkKetmdQ6MdZfQhCmEBiKmyVzrmu6OwXQMqHXTv8QxQXaHquaiWds7ZK/LfDLrH4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LfKNkqMJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LfKNkqMJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFDB6C4CEEA; Thu, 12 Jun 2025 11:37:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749728271; bh=RC6e67q4bD7RzUdBsPC19A7/O1+Ylly3nWUTzq8H6C0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LfKNkqMJ230N0EmQJ6n6F5hxs2eDHc2gDzUqnaFqxjR2BzP+se/A2VupzCMhrI4gb 9NYBUQi6O74YbTU15kOTP7LtYwDO6nlpekDG4/rRf81shqTxXz5puLtCfFMvrC1Ez8 lC0MdZSRw4aOzUbAy3MWk4X+otN1Bl7AvHQP+2SamIX9i1DphEmtbMo4CBHyTrmcS0 MUdzc/iYg1tYTc5iGlJ+oeZUq/maoaBSzH0FDgLo2Lkc4GZua4eYLruLegRywdBiqV mpLSscXiDGCpK6qASc0UCBqdRsHIBwtAVRWHdD2/UFkcmRUXp26vKsR4TOHPK4TG94 WUZI4sxPL5xPQ== Date: Thu, 12 Jun 2025 13:37:48 +0200 From: Frederic Weisbecker To: Xiongfeng Wang Cc: Joel Fernandes , linux-kernel@vger.kernel.org, "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang , rcu@vger.kernel.org, bpf@vger.kernel.org, xiqi2@huawei.com Subject: Re: [PATCH 2/2] rcu: Fix lockup when RCU reader used while IRQ exiting Message-ID: References: <20250609180125.2988129-1-joelagnelf@nvidia.com> <20250609180125.2988129-2-joelagnelf@nvidia.com> <5568ff6b-6d5c-ea63-3c4a-c0714103aa9d@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <5568ff6b-6d5c-ea63-3c4a-c0714103aa9d@huawei.com> Le Thu, Jun 12, 2025 at 11:06:07AM +0800, Xiongfeng Wang a écrit : > +cc (Qi, my colleague who helps testing the modification) > > On 2025/6/10 20:23, Frederic Weisbecker wrote: > > Le Mon, Jun 09, 2025 at 02:01:24PM -0400, Joel Fernandes a écrit : > >> During rcu_read_unlock_special(), if this happens during irq_exit(), we > > ...skipped... > > We have tested the below modification without the modification written by Joel > using the previous syzkaller benchmark. The kernel still panic. > The dmesg log is attached. Yes, it's a cleanup that doesn't include Joel's change yet. So this is expected. Thanks. -- Frederic Weisbecker SUSE Labs