From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-177.mta0.migadu.com (out-177.mta0.migadu.com [91.218.175.177]) (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 057D83624A8 for ; Tue, 28 Jul 2026 03:43:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785210187; cv=none; b=PcvEaeFmmcotXpNFMBs+yxxBZB4o8chYQhUr+AUrb0c9wuTYp0vKnnNXsAbaKH3YJD2FDJiljNND25pUO82dP516rKI4aGs6vzvqWpIi3XOhfArs4d3ljI75HSAZoXYxng0mXHIJKJHqDOS1hpuvNXFyY9qengMm5Mys7KF0GA8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785210187; c=relaxed/simple; bh=fyqvdyUtzbGrcFUiUwdNcNec15TSzu0Bhf7s5ubnQSo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=mL35CsMktcLqfS0Z3oKd9YIU5cpteBCVCJQuq97L6rhFvYM3eNCDmChbdAG0GMTyeK9IH0m9mW14D6W3VMQq9f1R6N7/s3x1hdkLMtsvEt2TBF+yCznzXDEqiZRuhC7wPA3QxfiSYWRntHxsTmofk3KEsrvxeNX1rDZgCAJQFQo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Ryzi+WFq; arc=none smtp.client-ip=91.218.175.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Ryzi+WFq" Message-ID: <95b8e484-c0d1-4973-b752-c93fb4cae1f4@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1785210171; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WFpxFaOxkYFI9NE7mVhHV4GeGovOkSIrDEM/enz8GA8=; b=Ryzi+WFq/tU6M1CX1qsxGTvA5QEDJTuuxniezA+1K+EnnbwXRx8o7jznolP0YJUz++/nM/ GKVP/BGmDz//Amcx9T6X5DpaLapAt01L4elmzvOtnKNW1589fuClYHZchhGG5Bf/xM2vxf hHGQ7oWRl2C37lrme9Y9r147BedBMS8= Date: Mon, 27 Jul 2026 20:42:07 -0700 Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [RFC PATCH 1/2] RDMA/rxe: drive UDP tunnel socket lifetime from the GID table To: Serhat Kumral , "yanjun.zhu@linux.dev" Cc: zyjzyj2000@gmail.com, xiongwm2026@163.com, jgg@ziepe.ca, leon@kernel.org, dsahern@kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+8c9eede336e3a843750e@syzkaller.appspotmail.com References: <20260726140253.26870-1-serhatkumral1@gmail.com> <20260727195521.34907-1-serhatkumral1@gmail.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Zhu Yanjun In-Reply-To: <20260727195521.34907-1-serhatkumral1@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2026/7/27 12:55, Serhat Kumral 写道: > I was pointed at Weimin Xiong's "RDMA/rxe: Hold netdev reference for > transmit skbs" (v3, 20260716055255.157674-1-xiongwm2026@163.com) and > tested with it applied. > > That patch and this series conflict in rxe_notify(). Its hunk carries > "rxe_net_del(&rxe->ib_dev);" as a context line, and this series removes > that call together with the function, so neither order applies with a > plain git apply. I resolved it by keeping both rxe_flush_qps() calls and > dropping the rxe_net_del() line: > > case NETDEV_GOING_DOWN: > /* Start draining TX queues before the netdev disappears. */ > rxe_flush_qps(rxe); > break; > case NETDEV_UNREGISTER: > rxe_flush_qps(rxe); > ib_unregister_device_queued(&rxe->ib_dev); > break; > > If the tree where the crash appears resolves it differently, that > difference is worth seeing. [root@fedora linux]# git log --oneline f2ec6312bf..HEAD c7b5816e800a (HEAD -> master) Merge branch 'master' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux 668b9a3b586c RDMA/rxe: Hold netdev reference for transmit skbs This is the command line " [ 0.000000] Command line: BOOT_IMAGE=(hd0,gpt2)/vmlinuz-7.2.0-rc3-rxe-l2+ root=UUID=511002c6-ecb8-4356-bd0b-7c54cc92384f ro rootflags=subvol=root rhgb quiet crashkernel=2G " Zhu Yanjun > > Four kernels on f2ec6312bf71, same config and toolchain as before, 120 > runs of rxe_rping_between_netns.sh each: > > f2ec6312bf71 120/120 > + this series 120/120 > + the netdev reference patch 120/120 > + the netdev reference patch + series 120/120 > > No KASAN report, GPF, Oops, refcount warning, lockdep splat, hung task or > RCU stall in any of them. The module symbol tables confirm each kernel > carries what it should: rxe_flush_qps only in the two with the netdev > reference patch, rxe_add_gid and rxe_del_gid only in the two with this > series. > > Four kernels reporting nothing made me doubt the setup rather than the > result, so I checked that it reports faults at all: a deliberate NULL > pointer dereference injected into the rxe transmit path, during the same > selftest, gives > > [ 69.131350] Oops: general protection fault, kernel NULL pointer > dereference 0x39: 0000 [#1] SMP KASAN NOPTI > [ 69.141660] Workqueue: rxe_wq do_work [rdma_rxe] > > It reaches the console I capture, my filters count it, and the iteration > is recorded as failed. From userspace the selftest just hangs. > > So it still does not reproduce here. > > thanks, > serhat