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 0A6F6606D802 for ; Tue, 3 Nov 2026 14:47:38 +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=C3fGYMNx; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=RMc4cr4T DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Reply-To:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Date: Content-Transfer-Encoding:Content-Type:References:In-Reply-To:Cc:To:Subject: From:Message-ID:MIME-Version:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=4+bnBfQZju8fpAB/8X14BeZjZQCkdXf0D+qDeon2Ak4=; b=C3fGYMNx17yuujNcKB3biae0eU B3YV1Ka+WgmxnBa8StaHhoOZZW6CzyVepE0wfJVbSFogiKBDygwZu6IiK1j3a/c/q/lpuoV2w4enx 9Bb2r30+2+SA9okAOmvdVorp0L+5wIM2kIQ20oWhXoZfik7tFvW05AjHGIVd4v30XiB9tGH41Fsgo OylyYMFF9Jjj/VfOO0R7IS70pIv/D5jvQfVZZhaWVYPqAcz5dyQwyBQukzneGPBtG43Sxax6Laa3r uihnUmBxqk9O8uWBU6A7UyadL5Xj3gpLnyXnbLihI05tJPhUQkSTTunSGkWiYZr6tNdxhpHXSJkTw rKrg6rpQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOFnV-00000002kcx-2yXj; Tue, 03 Nov 2026 14:47:37 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOFnR-00000002kbd-3KeV for kexec@lists.infradead.org; Tue, 03 Nov 2026 14:47:33 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 8A2A343C3D; Tue, 3 Nov 2026 14:47:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 01E0F1F000C1; Tue, 3 Nov 2026 14:47:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793717253; bh=4+bnBfQZju8fpAB/8X14BeZjZQCkdXf0D+qDeon2Ak4=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=RMc4cr4TMiothzZr1gQV3jJQjTeueKFUXv5zwuxzcbh5/HdxeLC2IglsSlv1VEwFv Ur/LQ/eR3wSsqQbS8ZUk0SCD2Jx4kztRhXfrHkH4Xo77UmXiqjwaE6vDGM+mgmJYHJ tuYlF3IhQZw5QVy6DfHtL2C9tEk+v13TCjTgx+HnNYr8+fPG6IYPcoxzaksDgA2jAp 31qr2fSSwX5A2grnozzQ2Af9r57Tn+8pY9j8ePIL8X9VbUZE1bN2J7wgKWw8Wgp+BQ 6U7CHQuUZsauwLE/6W1MtHqTP42XyAHvVqnScnEzcPB+Ebjn8acd6ZXDg8/h4mKSSS gUZdMs5bhS6lA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RFC 03/38] netfilter: xt_recent: don't remove the proc entries under a spinlock To: "Christian Brauner" Cc: "Linus Torvalds" , "Jann Horn" , "Josef Bacik" , "Chris Mason" , "Jeff Layton" , NeilBrown , "Eric Dumazet" , "Thomas Gleixner" , "Al Viro" , "Jonathan Corbet" , "Christoph Hellwig" , "Greg Kroah-Hartman" , "Joel Granados" , "Kees Cook" , "Jan Kara" , "Jan Kara" , linux-s390@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, linux-m68k@lists.linux-m68k.org, linux-serial@vger.kernel.org, "Takashi Iwai" , linux-ext4@vger.kernel.org, "Chuck Lever" , tytso@mit.edu, "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" In-Reply-To: <20261102-work-procfs-bugfixes-v1-3-59422ed3e465@kernel.org> References: <20261102-work-procfs-bugfixes-v1-0-59422ed3e465@kernel.org> <20261102-work-procfs-bugfixes-v1-3-59422ed3e465@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 03 Nov 2026 14:47:31 +0000 X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "kexec" X-Spam-Status: No, score=-10.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 X-Archived-By: > recent_proc_net_exit() removes the proc entries of all tables with > recent_lock held. remove_proc_entry() waits until nobody calls into the > entry anymore, and reading one of them takes recent_lock in > recent_seq_start() while procfs has the entry pinned. So when a reader > gets there while the network namespace goes away, the exit path sleeps > with a spinlock held and bh disabled, waiting for a reader that spins > on that very lock: >=20 > BUG: sleeping function called from invalid context at kernel/sched/comp= letion.c:116 > in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 12, name: kworke= r/u16:0 > locks held by kworker/u16:0/12: 4, last CPU#2: > #2: (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xbf/0x860 > #3: (recent_lock){+...}-{3:3}, at: recent_net_exit+0x3d/0x170 [xt_rece= nt] > Workqueue: netns cleanup_net > Call Trace: > [ ... ] > with a proc entry pinned takes it. So take recent_mutex instead. >=20 > Fixes: 665e205c16c1 ("netfilter: xt_recent: fix namespace destroy path") > Cc: stable@vger.kernel.org > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261102-work-procf= s-bugfixes-v1-0-59422ed3e465@kernel.org?part=3D3