From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4C8622517B0; Wed, 5 Mar 2025 17:56:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197390; cv=none; b=uk+F/UXOyWCoaZnCZB1W50GwTqQgoatQGagADhPfOaJclyNVR5SHUwR749+lsF6kp+ADbHxdTbXeUeIGbvuCs9BeNS33O8HcCXktTHTUDxQ86T0/WHsyS2bxO8Vd4kE2jv+oOyj6FTWzePNU4yncIHoS3RcDGkHCZaBuaQVk7Mk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197390; c=relaxed/simple; bh=hGMfOxKuezrZUiJVf7DVOJyjyMpwQyTK9eo2BQzDylg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HPxQAFxP+MGPGVQTxGb5s1HyePS+PITBkgFqmJI/+qg6nwWa8CKJOKFHVdXJzrcPKHySvRLwVLFyoMePGmH5Bb4GSIcc6chMU/bYwYcMMz8dp6DS9FyB5+spAOSM+W2r9iAAmr0iQXxyyJLxGdnZbXdEI6TIX7oVmWIEAYUThA8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vzM+sl1d; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="vzM+sl1d" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C838AC4CED1; Wed, 5 Mar 2025 17:56:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741197390; bh=hGMfOxKuezrZUiJVf7DVOJyjyMpwQyTK9eo2BQzDylg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vzM+sl1dbzN8oUvozppNkxv18vhx8h8A7Cv6B4yUI+kSXexYML7bMeUYc9rJEHWku HKcDkHtkxN4iOQeFd8bSO7a3RZTFGEA18a6BqeAVjEctBqFX1wOK/0pcO12w907BSF hTemJoa9unzdQyPHQEze8I54TmcM5rq5QJKs//Dw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Lingfeng , Trond Myklebust , Jeff Layton , Anna Schumaker , Sasha Levin Subject: [PATCH 6.1 108/176] SUNRPC: Prevent looping due to rpc_signal_task() races Date: Wed, 5 Mar 2025 18:47:57 +0100 Message-ID: <20250305174509.802756671@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250305174505.437358097@linuxfoundation.org> References: <20250305174505.437358097@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust [ Upstream commit 5bbd6e863b15a85221e49b9bdb2d5d8f0bb91f3d ] If rpc_signal_task() is called while a task is in an rpc_call_done() callback function, and the latter calls rpc_restart_call(), the task can end up looping due to the RPC_TASK_SIGNALLED flag being set without the tk_rpc_status being set. Removing the redundant mechanism for signalling the task fixes the looping behaviour. Reported-by: Li Lingfeng Fixes: 39494194f93b ("SUNRPC: Fix races with rpc_killall_tasks()") Signed-off-by: Trond Myklebust Reviewed-by: Jeff Layton Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- include/linux/sunrpc/sched.h | 3 +-- include/trace/events/sunrpc.h | 3 +-- net/sunrpc/sched.c | 2 -- 3 files changed, 2 insertions(+), 6 deletions(-) diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h index f80b90aca380a..a220b28904ca5 100644 --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -147,7 +147,6 @@ enum { RPC_TASK_NEED_XMIT, RPC_TASK_NEED_RECV, RPC_TASK_MSG_PIN_WAIT, - RPC_TASK_SIGNALLED, }; #define rpc_test_and_set_running(t) \ @@ -160,7 +159,7 @@ enum { #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate) -#define RPC_SIGNALLED(t) test_bit(RPC_TASK_SIGNALLED, &(t)->tk_runstate) +#define RPC_SIGNALLED(t) (READ_ONCE(task->tk_rpc_status) == -ERESTARTSYS) /* * Task priorities. diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h index ffe2679a13ced..b70f47a57bf6d 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -328,8 +328,7 @@ TRACE_EVENT(rpc_request, { (1UL << RPC_TASK_ACTIVE), "ACTIVE" }, \ { (1UL << RPC_TASK_NEED_XMIT), "NEED_XMIT" }, \ { (1UL << RPC_TASK_NEED_RECV), "NEED_RECV" }, \ - { (1UL << RPC_TASK_MSG_PIN_WAIT), "MSG_PIN_WAIT" }, \ - { (1UL << RPC_TASK_SIGNALLED), "SIGNALLED" }) + { (1UL << RPC_TASK_MSG_PIN_WAIT), "MSG_PIN_WAIT" }) DECLARE_EVENT_CLASS(rpc_task_running, diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index cef623ea15060..9b45fbdc90cab 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -864,8 +864,6 @@ void rpc_signal_task(struct rpc_task *task) if (!rpc_task_set_rpc_status(task, -ERESTARTSYS)) return; trace_rpc_task_signalled(task, task->tk_action); - set_bit(RPC_TASK_SIGNALLED, &task->tk_runstate); - smp_mb__after_atomic(); queue = READ_ONCE(task->tk_waitqueue); if (queue) rpc_wake_up_queued_task(queue, task); -- 2.39.5