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 865C717B505; Wed, 5 Mar 2025 18:06:03 +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=1741197963; cv=none; b=lCRKGa/hMGCik9h/pXW2u+lc8CIPmmo8dEwLQLdcQFGabbAyJhMWn4dUYwWS/Efcj976qaZe/aq+ZK8a8bly6rmVWJyee1Od11ltv6JVwU8dHK6upn0szONqaSucxKPTNZxQCwNLIxp7vFwAW8/M4hcAoyIFKCPglUB7SYm+AxY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197963; c=relaxed/simple; bh=f3yjP8yX2RKwlX2WNTpDq0nbPujXDjjngsa3HfLVsLI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CkTmAmj0ayoGuDteuwb5Zbxx+TgSjqwq5y0j/UUsQWFrcu0ymhtcU4X2RVmeNscu8Ip9inXb4SXIfb0xma/qZamY45b90mVl3ioQeYegE3SRBUFbYBiIKT5dzFDzp0EH98QrS5ClclbIDOhCg0wYWmn15uiDS4sRE2zFe6NE6Qc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=S+65UIlB; 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="S+65UIlB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D9F2C4CED1; Wed, 5 Mar 2025 18:06:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741197963; bh=f3yjP8yX2RKwlX2WNTpDq0nbPujXDjjngsa3HfLVsLI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S+65UIlBaGp0PqO/+j7dmJxVGjqpdGd/DcakSdSXZl+Pua+sTY8mZirI3wgo+EyVE ZEd85wiCq95wi5RnyJNvFCAuILpefqFEHopcJllbLTospLIS3R7LNLs6we0gacA2oK LnToAGoXawKUBR/2Q7C+sBLqoZiuEFSU/+x63i6Y= 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 6.12 018/150] SUNRPC: Prevent looping due to rpc_signal_task() races Date: Wed, 5 Mar 2025 18:47:27 +0100 Message-ID: <20250305174504.541555875@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250305174503.801402104@linuxfoundation.org> References: <20250305174503.801402104@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 6.12-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 fec1e8a1570c3..eac57914dcf32 100644 --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -158,7 +158,6 @@ enum { RPC_TASK_NEED_XMIT, RPC_TASK_NEED_RECV, RPC_TASK_MSG_PIN_WAIT, - RPC_TASK_SIGNALLED, }; #define rpc_test_and_set_running(t) \ @@ -171,7 +170,7 @@ 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 5e84952166895..5fe852bd31abc 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -360,8 +360,7 @@ 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