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 71CB8384226; Thu, 5 Mar 2026 11:20:06 +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=1772709606; cv=none; b=BggD7Th2vx6fp0REeOptBMOXQvi9XftarQXhcp9JaC+LMujiJplKWDDAUBD8G80gxqX28DChd8I9tU4TYzJ9A3bMzx5AMcRLD8zLVeQxMa3YT2BVEnSenYIxYKhVpeLwcB5Hlz4FLkwMNNsbiuop2mgPa9p9wsDScmwRoXHzAag= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772709606; c=relaxed/simple; bh=elaEEUTv4MbbTzOnb1aluZ6NJgO+oaUQdHPfgS+bsrI=; h=Content-Type:MIME-Version:Subject:From:Message-Id:Date:References: In-Reply-To:To:Cc; b=CPgBzR2JOVD8V9eGqSn+9iyd96fSJigH9/PwG3arP5ZvmvYIeo0dzdavDj2iB7B6YLQeadya/wWnczw/nDJvdaU5pExfEivuFPnE4gYwYGzNjca2AktjjhzoQPrHMVGZW4ZisBdgFH2ZH4zkJCK9nnzsWbaHBi9K0ztRxr4mMio= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=J4armBV4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="J4armBV4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0444AC116C6; Thu, 5 Mar 2026 11:20:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772709606; bh=elaEEUTv4MbbTzOnb1aluZ6NJgO+oaUQdHPfgS+bsrI=; h=Subject:From:Date:References:In-Reply-To:To:Cc:From; b=J4armBV42aMPkC4rjz7LiHT08N90u6/E6ZW/wTSXq2bYgC3YXROya4EoHIXrD3LQ8 LrqLNgFSjeoOCTqOnVfuOwHNsRohTC/cteg7PUjg/4uLhf697D61JzL7zLvR8moB4M /GEmLUxPmOKwl9xl81dHyuQ0qtdr891ARv8KSDO8eZpPxkxt7HPvKFA927VCN0iNBa ZHuCs+7Ig2kCaie3Z6eFMzxgTl6+pSzOEQfwUYytaPcwLTGKKadbWU8YL6IK5riFlj 3xKlIO9fUl9W3rAUmP2PMT9qB0hlw8XfnooeJQxuO1intqzGtEFtRaZTCxZj2gKM3N gg2zFpVvTm42w== Received: from [10.30.226.235] (localhost [IPv6:::1]) by aws-us-west-2-korg-oddjob-rhel9-1.codeaurora.org (Postfix) with ESMTP id 3FE693808200; Thu, 5 Mar 2026 11:20:07 +0000 (UTC) Content-Type: text/plain; charset="utf-8" Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH net] net: Provide a PREEMPT_RT specific check for netdev_queue::_xmit_lock From: patchwork-bot+netdevbpf@kernel.org Message-Id: <177270960605.2657587.18286685206790931125.git-patchwork-notify@kernel.org> Date: Thu, 05 Mar 2026 11:20:06 +0000 References: <20260302162631.uGUyIqDT@linutronix.de> In-Reply-To: <20260302162631.uGUyIqDT@linutronix.de> To: Sebastian Andrzej Siewior Cc: netdev@vger.kernel.org, linux-rt-devel@lists.linux.dev, davem@davemloft.net, andrew+netdev@lunn.ch, spasswolf@web.de, clrkwllms@kernel.org, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, rostedt@goodmis.org Hello: This patch was applied to netdev/net.git (main) by Paolo Abeni : On Mon, 2 Mar 2026 17:26:31 +0100 you wrote: > After acquiring netdev_queue::_xmit_lock the number of the CPU owning > the lock is recorded in netdev_queue::xmit_lock_owner. This works as > long as the BH context is not preemptible. > > On PREEMPT_RT the softirq context is preemptible and without the > softirq-lock it is possible to have multiple user in __dev_queue_xmit() > submitting a skb on the same CPU. This is fine in general but this means > also that the current CPU is recorded as netdev_queue::xmit_lock_owner. > This in turn leads to the recursion alert and the skb is dropped. > > [...] Here is the summary with links: - [net] net: Provide a PREEMPT_RT specific check for netdev_queue::_xmit_lock https://git.kernel.org/netdev/net/c/b824c3e16c19 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html