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Tue, 29 Oct 2024 12:46:02 +0000 (GMT) Message-ID: <22ac5b67-9968-4c53-af90-dd83b0efbd76@linux.ibm.com> Date: Tue, 29 Oct 2024 18:16:01 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/3] Revert "nvme: make keep-alive synchronous operation" To: Ming Lei Cc: linux-nvme@lists.infradead.org, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me, axboe@fb.com, chaitanyak@nvidia.com, dlemoal@kernel.org, gjoyce@linux.ibm.com References: <20241027170209.440776-1-nilay@linux.ibm.com> <20241027170209.440776-2-nilay@linux.ibm.com> Content-Language: en-US From: Nilay Shroff In-Reply-To: Content-Type: text/plain; charset=UTF-8 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: Yy56sXWXrgBQmsqidKuFA1kDXtsUytgR X-Proofpoint-ORIG-GUID: Yy56sXWXrgBQmsqidKuFA1kDXtsUytgR Content-Transfer-Encoding: 8bit X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_01,2024-10-11_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=874 clxscore=1015 adultscore=0 mlxscore=0 priorityscore=1501 spamscore=0 malwarescore=0 impostorscore=0 lowpriorityscore=0 bulkscore=0 phishscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410290097 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241029_054613_009628_E628DD7E X-CRM114-Status: GOOD ( 19.21 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 10/29/24 12:18, Ming Lei wrote: > On Mon, Oct 28, 2024 at 1:03 AM Nilay Shroff wrote: >> >> This reverts commit d06923670b5a5f609603d4a9fee4dec02d38de9c. >> This reverts commit 599d9f3a10eec69ef28a90161763e4bd7c9c02bf. >> >> It was realized that the fix implemented to avoid the race >> condition between keep alive task and the fabric shutdown code >> path in the commit d06923670b5ia ("nvme: make keep-alive >> synchronous operation") is not optimal. > > I saw you have discussed it a while, but it is still better to describe > the reason in the commit log. > Sure, I would enhance the commit message to clarify it further. >> >> We also found that the above race condition is regression caused >> due to the changes implemented in commit a54a93d0e359 ("nvme: move >> stopping keep-alive into nvme_uninit_ctrl()"). So we decided to > > Can you explain a bit why commit a54a93d0e359 is a regression? > And what is the race condition? > > Without providing the context info, it is hard to review the change. > > Thanks, > > OK, the root cause of the race condition and how it could be triggered has been already discussed here[1]. In any case, if you still want me to clarify it further then please let me know. [1]https://lore.kernel.org/all/b03863b2-8816-48cd-aa18-436f1c49ec8c@linux.ibm.com Thanks, --Nilay