From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C0C45606A31D for ; Wed, 21 Oct 2026 21:01:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=IbBqSCCp; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=IoR+o3ND 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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9xFDwKa9QE4RkXSn8pB3Ype9/9E+5MMs7HrH2FQlI88=; b=IbBqSCCp0BDuBrOpEpUQiYep2s 6yee/tbuGlxbJhpVtsBuY2xaR1biQsffbcDSJ8uZtloCFFU1w78EVEchmXmgwBGlm+X/7ltZgcNss Kgh2bcd0PdhMZT8/Z5G3r4Pry6LOzjK9KorkG44JfgHtUOkZnGX/sFq06xIu1jN7O+HZ/d5lt1LCm Sj+Sjb0ZS5PR29xV/JyidguiOT02UVZDyz7Xgp/jWqEoD+HKLMzAnL2vaRUIMTASvzYzjlHFd1K+q qBC3hgeK4BX1ODPQvCs+m7PwGWzGlKWy8SUasRibQSsSFOKBD1bJaFA4gXL4DYeAxBCBELN8D/Xkm J/JfZblA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xJdQt-0000000Ct05-1yLy; Wed, 21 Oct 2026 21:01:11 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xJdQs-0000000CszN-42EK for linux-nvme@lists.infradead.org; Wed, 21 Oct 2026 21:01:11 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 43BF1602D3; Wed, 21 Oct 2026 21:01:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 629C51F000C1; Wed, 21 Oct 2026 21:01:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792616470; bh=9xFDwKa9QE4RkXSn8pB3Ype9/9E+5MMs7HrH2FQlI88=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=IoR+o3NDBCbVzx84h6KUCMBpq9z9MmhjRp+GwGzx1iOzdg041DTSdBwRmG8vwROCR y8+hHxzBHJddtwOQOETh3Pv/ickuZbLpyg2VoCjaroTQJcTJkv8xVBmmhvZ4MJTF5O 53Q0I1CAENdcAVZbdxuB+MzJccXA8v938TRmBLXtBs5pjtfmN0JM/WF9GbsGMXpLih Yji9iEOGTpsPPGHJJrIN60SuZ9Ifgm6lq3Lv7KYuwo6/tFHmoB7VB2k0ENa8b9xv9q gjMYrF1RCEyY5ltlVzur4riJCoalnifF3QketRB7dkJZuWsvg8MrPyQRBQqQ67366i BcV4K1YukWElQ== Date: Wed, 21 Oct 2026 15:01:08 -0600 From: Keith Busch To: Daniel Wagner Cc: Jens Axboe , Christoph Hellwig , Sagi Grimberg , Ming Lei , Surabhi Gogte , Hannes Reinecke , Nilay Shroff , Frederic Weisbecker , Aaron Tomlin , Maurizio Lombardi , Sebastian Andrzej Siewior , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Daniel Wagner Subject: Re: [PATCH 0/5] nvme-fabrics: fix connects with isolated CPUs and queue mapping bugs Message-ID: References: <20261014-nvme-fabrics-isolcpu-v1-0-355156be27b2@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261014-nvme-fabrics-isolcpu-v1-0-355156be27b2@kernel.org> X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" X-Spam-Status: No, score=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Wed, Oct 14, 2026 at 09:46:38AM +0200, Daniel Wagner wrote: > Connecting a fabrics controller fails when all CPUs of a hardware > context are isolated with isolcpus=domain or an isolated cpuset > partition. Since commit a46c27026da1 ("blk-mq: don't schedule block > kworker on isolated CPUs") the CPU mask of such a hardware context is > empty and blk_mq_alloc_request_hctx() fails the Connect command with > -EXDEV. Patch 2 lets passthrough requests use the software context of a > housekeeping CPU instead. > > Patches 3-5 fix the fabrics queue mapping: > > - Stale io_queues[] entries after a reconnect with fewer queues crash > blk_mq_map_swqueue(). > - A queue type can get more queues than online CPUs, so connecting > fails with -EXDEV. > - Without queues left for polling, the queue claims poll support and > polled I/O ends up on a non-poll queue. > > Patch 1 fixes a regression in nvme-7.4 found while testing: since commit > 61b0ed3be81b ("nvme-tcp: parallelize I/O queue allocation and startup") > nvme_tcp_init_request takes a mutex before it is initialized, which > disables lock debugging on the first connect. It seems the nvme patches (1, 3-5) can be applied independently of the blk-mq patch, so I staged those in nvme-7.4.