From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793726001; b=zde80WC7Qz9MGysvRDwqAdgeRRMusTEJ8s/+QBdzkepmIYGWhKCXzPakzi2CKY/qRJqa xqf2p/y4xbvgYAHw6kfbJZCkjcNHXFQz+T5bdrbEjgVlwVV83+qbLNLKYjFM+0r+KgUse VUJxG9Uan9UCcVLPA3PWeG51fXpTa5nsF0wjX7ep/j4vpD1PrdrhQfMV/qSSJ1lf0DUWB RoIa84f4fVloXyuERlBE2QxKx//wNjvw7G9a8bueZsyomsyod56DTomy6QfL+2ipC8MAz seTIrn4//ydAylKcDOX2qD4kVwneKbCTWUba97da5pwJDMGWAEr6hz1K6OBrNPupVgA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793726001; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=XGahh9LKQSxFZ7LuxgMQZ7w7FnBXKhyeqWtawQJw9sA=; b=tjVvvOYa5DgD2N68s5aYULmNxE+xQ3iuNf3zGdQBGT0hT52oefKnGPtOML1ktWKKfHbe 7zt6ZrwoCoSoR5R6Lxv2UxsrIT4yTfxoJS6Xox+Jkejy0Hq8kVkY0Ced2GTXRLomJFybU Z76eZrKRN9R7FfE9ebPgX7A5Nqx4Fi0eTQDH+jnx3D06JjwTIIBcbfR+r/8fSUU0Yl+S1 PFGXlvK6S89fF4EE2tCTZgAV8jKxg0djeMEW66bANC0MRV09rEIRWs2kHHSDExq0qmf/V sZ7LaZUOI/I//u4XScc48P65na55PnnT4aft/o+vTUEjG7NkKIJayyzRfJ47tNc5sYQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=YCDYPwJg; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 29379606EEA0 for ; Tue, 3 Nov 2026 17:13:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=YCDYPwJg Received: by smtp.kernel.org (Postfix) with ESMTPSA id A5FE31F00A16; Tue, 3 Nov 2026 17:13:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793726000; bh=XGahh9LKQSxFZ7LuxgMQZ7w7FnBXKhyeqWtawQJw9sA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=YCDYPwJgnu5S6u+ldRqUeOOKdvp9Ct7R3lmAN2Yklv1r7vMcpR1ixRLo5ISyVSpZ7 RRnuh4+hP1o2f/KvoHv40LqOAwg6Am2io6QZdnQth4PYdX0NKrbvgmhbWcLvLu9cSL SQYEUA0YEKdC/wvqCAxgEaosrL2kTZjAC/SZewDtavSosZXlVRqn7EpiTUoZt/0o7+ VSQfd+4IkDzJDwsZ6VBavvXeAvIgw4NPQZ0iStYUOmzz0/WsmXlbwFjKNwWmxJe6VP D0oNtjKBUljzOPqJGm+57tPYq4KoiZgwuovNc68d+mNvskSbluF/LxEMeNOTxhEE2D wc1Gc+gQA/gzQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH] RDMA/ipoib: cancel the AH reaper work synchronously Reply-To: sashiko-reviews@lists.linux.dev To: "Chengyu Liu" Cc: linux-rdma@vger.kernel.org In-Reply-To: <20261103170703.1600310-1-lui2012qwq@gmail.com> References: <20261103170703.1600310-1-lui2012qwq@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 03 Nov 2026 17:13:20 +0000 X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > ipoib_stop_ah_reaper() uses cancel_delayed_work(), which cannot stop a > callback that is already running. ipoib_reap_ah() re-arms itself after > an unlocked test_bit(IPOIB_STOP_REAPER) check, so a callback that has > passed the check but has not re-armed yet still queues the delayed work > after the "stop": >=20 > CPU0 (reaper) CPU1 (stop/teardown) > test_bit(STOP_REAPER) =3D=3D 0 > set_bit(STOP_REAPER) > cancel_delayed_work() (no-op) > ... destroy_workqueue(priv->wq) > queue_delayed_work(priv->wq, ...) <- delayed work sits on the timer >=20 > destroy_workqueue() cannot see a delayed work that is pending on the > timer wheel, so the re-armed work fires after the workqueue is > [ ... ] > with a small module exercising this exact guard/cancel/free pattern > (no Infiniband hardware available); PoC and splat are below. >=20 > Cc: stable@vger.kernel.org > Signed-off-by: Chengyu Liu Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261103170703.1600= 310-1-lui2012qwq@gmail.com?part=3D1