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 AA69E308F3A; Tue, 17 Mar 2026 16:40:56 +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=1773765656; cv=none; b=AY4cVQrrjIpBT01r5CUNhQ7/UBBcwpMDS17VGLaeXqenkj3CkfwfJHOgx17qTiCQcthGwySGZQRbFYZ8rM0EL7RcBTl7hrZroKxJSDxKWpER7aq7KvgkeFQ9oOAamGxYFJDev+Z9TyDkflb0p2LGpPHAJ8N23UI7N/JL0jJp9RE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773765656; c=relaxed/simple; bh=gris/42CdNSg8xRq0IFXn1gNt5AFOO1FDGLVK5f4DA0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MMuOd7x2f6L0x/xS3kpluFc/aItb2rMioYd0813L9rLgdVd41VH7fteke+wX/9Nx1ROFnBxGl05X9F80NobW8I1/TWfgCn93c4i1H27lDZJXdec/Ia1vBJMHdRoiOhKIoo7qbANueC3NHRfI4BZMOLX3ko2Xq9qD9XU4X7pWB9w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hr3o97tW; 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="hr3o97tW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 344EAC4CEF7; Tue, 17 Mar 2026 16:40:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773765656; bh=gris/42CdNSg8xRq0IFXn1gNt5AFOO1FDGLVK5f4DA0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hr3o97tW0+ahy6kUb+Jw2+cAYGzZgKmIqmB1lj/NIZ8PH9uuGmNEbmdeyC6QeTBE4 kEmC4qM3Z4M1fM+zpdHPTkMwvvVtUhH5tpb6xw9zwzXwFfoOaPDKLIxxvFlKG2Bfw6 /4ci/RPOxArRqBvsGeaDfCvq1VCKUi5g4dwqrutI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Badger , Chuck Lever , Anna Schumaker , Sasha Levin Subject: [PATCH 6.19 029/378] xprtrdma: Decrement re_receiving on the early exit paths Date: Tue, 17 Mar 2026 17:29:46 +0100 Message-ID: <20260317163008.050556929@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317163006.959177102@linuxfoundation.org> References: <20260317163006.959177102@linuxfoundation.org> User-Agent: quilt/0.69 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 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Badger [ Upstream commit 7b6275c80a0c81c5f8943272292dfe67730ce849 ] In the event that rpcrdma_post_recvs() fails to create a work request (due to memory allocation failure, say) or otherwise exits early, we should decrement ep->re_receiving before returning. Otherwise we will hang in rpcrdma_xprt_drain() as re_receiving will never reach zero and the completion will never be triggered. On a system with high memory pressure, this can appear as the following hung task: INFO: task kworker/u385:17:8393 blocked for more than 122 seconds. Tainted: G S E 6.19.0 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u385:17 state:D stack:0 pid:8393 tgid:8393 ppid:2 task_flags:0x4248060 flags:0x00080000 Workqueue: xprtiod xprt_autoclose [sunrpc] Call Trace: __schedule+0x48b/0x18b0 ? ib_post_send_mad+0x247/0xae0 [ib_core] schedule+0x27/0xf0 schedule_timeout+0x104/0x110 __wait_for_common+0x98/0x180 ? __pfx_schedule_timeout+0x10/0x10 wait_for_completion+0x24/0x40 rpcrdma_xprt_disconnect+0x444/0x460 [rpcrdma] xprt_rdma_close+0x12/0x40 [rpcrdma] xprt_autoclose+0x5f/0x120 [sunrpc] process_one_work+0x191/0x3e0 worker_thread+0x2e3/0x420 ? __pfx_worker_thread+0x10/0x10 kthread+0x10d/0x230 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x273/0x2b0 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Fixes: 15788d1d1077 ("xprtrdma: Do not refresh Receive Queue while it is draining") Signed-off-by: Eric Badger Reviewed-by: Chuck Lever Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- net/sunrpc/xprtrdma/verbs.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 63262ef0c2e3a..8abbd9c4045a4 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -1362,7 +1362,7 @@ void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, int needed) needed += RPCRDMA_MAX_RECV_BATCH; if (atomic_inc_return(&ep->re_receiving) > 1) - goto out; + goto out_dec; /* fast path: all needed reps can be found on the free list */ wr = NULL; @@ -1385,7 +1385,7 @@ void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, int needed) ++count; } if (!wr) - goto out; + goto out_dec; rc = ib_post_recv(ep->re_id->qp, wr, (const struct ib_recv_wr **)&bad_wr); @@ -1400,9 +1400,10 @@ void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, int needed) --count; } } + +out_dec: if (atomic_dec_return(&ep->re_receiving) > 0) complete(&ep->re_done); - out: trace_xprtrdma_post_recvs(r_xprt, count); ep->re_receive_count += count; -- 2.51.0