From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 51C8FD0E6CD for ; Tue, 25 Nov 2025 12:33:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6H3ZohGhsJTuXJwPtJPtAzAFvIuUq1M/+91P5tuAAAM=; b=M8QS1Utgx+lEjL0S4dCVDcjiv2 P1M1bnuEnNRo64CkWHzfbMQESbgX2TRmlBW+DwGUWAtmCfCLSD8zUSARlK+qK3yZhsIul1rvOp7Jh m8jES5qUPKqlVRlukbMz8JXsWT6ivT41dvtg+xnM3eNkXlvhTTxChnJ53Er0vtdDNygWQp74wKV+W dXsXN2KvyWdIsfoXB3MINepROqGwZTKY/zi11o1V6S0642g9dM8WaWxaSE86vhmc+S/NZO/SkCcGc 7HEsHGQrlwJyyuwHIfEMGc8Y3oezOGlekKQHx9omGPNpavdygpAYxNZu4v5pJyksLy1xoEpKdA96U gnOsK55w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vNsEz-0000000DHql-1MDo; Tue, 25 Nov 2025 12:33:53 +0000 Received: from smtp-out2.suse.de ([195.135.223.131]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vNsEw-0000000DHqC-13lt for linux-nvme@lists.infradead.org; Tue, 25 Nov 2025 12:33:52 +0000 Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 843325BE71; Tue, 25 Nov 2025 12:33:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1764074026; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6H3ZohGhsJTuXJwPtJPtAzAFvIuUq1M/+91P5tuAAAM=; b=uLChw0LO71V8jndqtzmCZ7btu5AMbJbgubtEdv0GIKDaqoHjwVDgBBqkT80YhxrmY41/3A I4NaNNP9hPTA9aNe+m2aMs1ITNji68siNBFjSprR8c9yh5KSLeApJ3dzK7yNnOw6WmJMre sJAj3AD6gk99KhiMA7rWm6GZLKI/2Ug= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1764074026; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6H3ZohGhsJTuXJwPtJPtAzAFvIuUq1M/+91P5tuAAAM=; b=BWJrJ9zBNbn0awaKiCsT2NIXmz/r5xo6ywZ8pzCZ6GPksVfOP9fK57rWvgFjYSJi70Lo8D lsHJmjos8g2rsjDg== Authentication-Results: smtp-out2.suse.de; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=uLChw0LO; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=BWJrJ9zB DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1764074026; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6H3ZohGhsJTuXJwPtJPtAzAFvIuUq1M/+91P5tuAAAM=; b=uLChw0LO71V8jndqtzmCZ7btu5AMbJbgubtEdv0GIKDaqoHjwVDgBBqkT80YhxrmY41/3A I4NaNNP9hPTA9aNe+m2aMs1ITNji68siNBFjSprR8c9yh5KSLeApJ3dzK7yNnOw6WmJMre sJAj3AD6gk99KhiMA7rWm6GZLKI/2Ug= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1764074026; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6H3ZohGhsJTuXJwPtJPtAzAFvIuUq1M/+91P5tuAAAM=; b=BWJrJ9zBNbn0awaKiCsT2NIXmz/r5xo6ywZ8pzCZ6GPksVfOP9fK57rWvgFjYSJi70Lo8D lsHJmjos8g2rsjDg== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 22FA83EA63; Tue, 25 Nov 2025 12:33:45 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id g5PzAymiJWkIdAAAD6G6ig (envelope-from ); Tue, 25 Nov 2025 12:33:45 +0000 Message-ID: <718aae86-a8dd-4b1d-9666-8d3a2bc5bc49@suse.de> Date: Tue, 25 Nov 2025 13:33:44 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC blktests fix PATCH] tcp: use GFP_ATOMIC in tcp_disconnect To: Nilay Shroff , Christoph Hellwig Cc: Chaitanya Kulkarni , Chaitanya Kulkarni , "kbusch@kernel.org" , "sagi@grimberg.me" , "axboe@kernel.dk" , "dlemoal@kernel.org" , "wagi@kernel.org" , "mpatocka@redhat.com" , "yukuai3@huawei.com" , "xni@redhat.com" , "linan122@huawei.com" , "bmarzins@redhat.com" , "john.g.garry@oracle.com" , "edumazet@google.com" , "ncardwell@google.com" , "kuniyu@google.com" , "davem@davemloft.net" , "dsahern@kernel.org" , "kuba@kernel.org" , "pabeni@redhat.com" , "horms@kernel.org" , "netdev@vger.kernel.org" , "linux-nvme@lists.infradead.org" , "linux-block@vger.kernel.org" References: <20251125061142.18094-1-ckulkarnilinux@gmail.com> <0caa9d00-3f69-4ade-b93b-eea307fe6f72@linux.ibm.com> <20251125112111.GA22545@lst.de> <234bab6c-6d31-4c93-8a69-5b3687ba9b85@linux.ibm.com> <20251125113009.GA22874@lst.de> Content-Language: en-US From: Hannes Reinecke In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 843325BE71 X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; URIBL_BLOCKED(0.00)[suse.de:email,suse.de:mid,suse.de:dkim]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FUZZY_RATELIMITED(0.00)[rspamd.com]; ARC_NA(0.00)[]; RCPT_COUNT_TWELVE(0.00)[26]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_TRACE(0.00)[0:+]; TO_DN_EQ_ADDR_SOME(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; FREEMAIL_CC(0.00)[nvidia.com,gmail.com,kernel.org,grimberg.me,kernel.dk,redhat.com,huawei.com,oracle.com,google.com,davemloft.net,vger.kernel.org,lists.infradead.org]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from]; RCVD_VIA_SMTP_AUTH(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; R_RATELIMIT(0.00)[to_ip_from(RLykmtnuwwt3p9ueb9muqcqoc7)]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,suse.de:email,suse.de:mid,suse.de:dkim] X-Rspamd-Action: no action X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251125_043350_601601_458C8905 X-CRM114-Status: GOOD ( 17.89 ) 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 11/25/25 12:54, Nilay Shroff wrote: > > > On 11/25/25 5:00 PM, Christoph Hellwig wrote: >> On Tue, Nov 25, 2025 at 04:58:32PM +0530, Nilay Shroff wrote: >>> >From git history, I see that was added to avoid memory reclaim to avoid >>> possible circular locking dependency. This commit 83e1226b0ee2 ("nvme-tcp: >>> fix possible circular locking when deleting a controller under memory >>> pressure") adds it. >> >> I suspect this was intended to be noio, and we should just switch to >> that. >> > Yeah, I agree that this should be changed to noio. However, it seems that > this alone may not be sufficient to fix the lockdep splat reported here. > Since the real work of fput() might be deferred to another thread, using a noio > scope in this path may not have the intended effect and could end up being > redundant. > > That said, I noticed another fix from Chaitanya [1], where fput() is replaced > with __fput_sync(). With that change in place, combining the noio scope adjustment > with the switch to __fput_sync() should indeed address the lockdep issue. Given > that both problems have very similar lockdep signatures, it might make sense to > merge these two changes into a single fix. > > [1] https://lore.kernel.org/all/20251125005950.41046-1-ckulkarnilinux@gmail.com/ > Yes, we should. Both address similar symptoms, and I wouldn't be surprised both turn out to address the same issue. (Frame #0 from here is basically identical to frame #2 in the referenced issue). So please roll both into one patch. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich