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 395701474B8; Mon, 5 May 2025 22:54:49 +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=1746485689; cv=none; b=FVibT3rZT1KA+32GSELJOkgb+RrDPMv323EazPXFBEzieXC3tDxWWtvd8uVfcSp6uGzzVQHyeoUbARMN+p5pWoNXnUwA24myWr3DZ32UgXC6dQCjmMBmMVtrkWExODj6+rs5Hb+Q8FIBWD7Wy4l/va+eFlRscQNv83lGUKry/1A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746485689; c=relaxed/simple; bh=VVgmndga1VaSEzVBYDI4b53/Gvrf7qNKSw0GXrRXzHw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=CsFfwWa4o2q3em2csac4GgIwReQeAh4EMSnK2jcm19ypuu8EneLN2KKbBOsbiHCtJv1f7mJgVPwka28nqKzwqAm+suqb6tGdOYGbGXli7JTJ4LzAf2MuBAWRT4E2I8/CUC021UWgbMbSAFV3YJqy/rMr13SWbe/oajoLYeNezbg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t/ThmBnN; 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="t/ThmBnN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B03F1C4CEE4; Mon, 5 May 2025 22:54:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746485689; bh=VVgmndga1VaSEzVBYDI4b53/Gvrf7qNKSw0GXrRXzHw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t/ThmBnNDUPoAHYVD/lJUO+OihvSVYG5+UN7EcP9Pr03i2irSnUNO2r/GRYF5lgPK JQbPJvdeS4K8JvJ4i001Rh/iTItO72aV2a6FSNM/wh04saVqIDG1sN0uUd9ca6URO7 WrnvoDIlIQBGmgpAssBLEPN2TGb3BWP3jTLVA0NWa6o2XS1Epu8OPB4q+nywKU2Xt9 BQibEC6FjovilEvbzs9nAFG4xSgdvDhRId0iYa+PHYHcU4sGa7E9dpZcDzbgHr/zJi 7LTPhMA8/qj6TrWD3BoN9YZWl8ExH/la9DVn/ED5KrvFkgafhpqOtZT650IsKk1HIb 6o0gVekAfpemg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , Jason Xing , Jakub Kicinski , Sasha Levin , davem@davemloft.net, pabeni@redhat.com, kuniyu@amazon.com, sdf@fomichev.me, ahmed.zaki@intel.com, aleksander.lobakin@intel.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 6.12 427/486] net: flush_backlog() small changes Date: Mon, 5 May 2025 18:38:23 -0400 Message-Id: <20250505223922.2682012-427-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505223922.2682012-1-sashal@kernel.org> References: <20250505223922.2682012-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.26 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit cbe08724c18078564abefbf6591078a7c98e5e0f ] Add READ_ONCE() around reads of skb->dev->reg_state, because this field can be changed from other threads/cpus. Instead of calling dev_kfree_skb_irq() and kfree_skb() while interrupts are masked and locks held, use a temporary list and use __skb_queue_purge_reason() Use SKB_DROP_REASON_DEV_READY drop reason to better describe why these skbs are dropped. Signed-off-by: Eric Dumazet Reviewed-by: Jason Xing Link: https://patch.msgid.link/20250204144825.316785-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/dev.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 7b7b36c43c82c..2ba2160dd093a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6034,16 +6034,18 @@ static DEFINE_PER_CPU(struct work_struct, flush_works); static void flush_backlog(struct work_struct *work) { struct sk_buff *skb, *tmp; + struct sk_buff_head list; struct softnet_data *sd; + __skb_queue_head_init(&list); local_bh_disable(); sd = this_cpu_ptr(&softnet_data); backlog_lock_irq_disable(sd); skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { - if (skb->dev->reg_state == NETREG_UNREGISTERING) { + if (READ_ONCE(skb->dev->reg_state) == NETREG_UNREGISTERING) { __skb_unlink(skb, &sd->input_pkt_queue); - dev_kfree_skb_irq(skb); + __skb_queue_tail(&list, skb); rps_input_queue_head_incr(sd); } } @@ -6051,14 +6053,16 @@ static void flush_backlog(struct work_struct *work) local_lock_nested_bh(&softnet_data.process_queue_bh_lock); skb_queue_walk_safe(&sd->process_queue, skb, tmp) { - if (skb->dev->reg_state == NETREG_UNREGISTERING) { + if (READ_ONCE(skb->dev->reg_state) == NETREG_UNREGISTERING) { __skb_unlink(skb, &sd->process_queue); - kfree_skb(skb); + __skb_queue_tail(&list, skb); rps_input_queue_head_incr(sd); } } local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); local_bh_enable(); + + __skb_queue_purge_reason(&list, SKB_DROP_REASON_DEV_READY); } static bool flush_required(int cpu) -- 2.39.5