From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 CF1D03A1B5; Wed, 19 Aug 2026 23:46:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787183174; cv=none; b=Y8oFmWAKUty9RHPA7UeVoN4wYYTCll+AU4MTKcxMT+4bAADgAjlBOolVkrxFilFCY7AzVQYF1VFoa/syFsz1JhxHWIkErna3FKE2UaS0Yam9o9HkmJMbDNDITjV9qqavxKksdZttiSia8QVHfXpmcD1RTF1qd51j/R9+M2zvhr0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787183174; c=relaxed/simple; bh=cTA3PHnOJJeih2mK0UbQNfwDOB3+Skd+oBXosgCJGEY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=tQSrvy88rcTTrPt+8xHYdp4Fk3DzPpkn3WIC4DOZCsi4y5RCPQSxxcboam/7puVKLFi3JR+Y8i85ZhxzpUnjEFtTbq9WwO7U1mgLUt7QODmw0PnkwMqywTq3Eq1Ba+/km7JTV3kpPJP41VtX8507+3oAb/onM7BoSgcTTbUjsHk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=T1+gAsQY; arc=none smtp.client-ip=192.198.163.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="T1+gAsQY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1787183173; x=1818719173; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=cTA3PHnOJJeih2mK0UbQNfwDOB3+Skd+oBXosgCJGEY=; b=T1+gAsQYTwUbFRjjviT1jVhNEIDpRi2PihS/j2uRjPlCmruYRFLHsSqj /z4H2arp8YZDxSYffWAhsBbgthb6NOyZN/HuEGQRKebXI8qa8lBWU6jQm Tj9zJa4wPERRkPxAEHj4oTx5C/66WKqu8I8DnIV9ayy6BgZTrtTNnh3jJ gjo8em+DJZ5IPJzAkCXlKysIgtw8DSU4ZrqQ4Zf77Sig80gIHQvSuB6Cq pZklxIj+n/aNnpv/qO8dkdP6KUn54U7ey/53rEoksRrGhArw7wFdi4IZ3 M1aLWtWKjc43BfSPpMr8S2UfpVyPTJvZ8SK1+0lLxAjGepTykqJGtkUpt A==; X-CSE-ConnectionGUID: YaLn/WUbST6gqz7pFpu9Fg== X-CSE-MsgGUID: 381BPFLdQoa1OpFFFqtDUg== X-IronPort-AV: E=McAfee;i="6800,10657,11880"; a="113252287" X-IronPort-AV: E=Sophos;i="6.25,232,1779174000"; d="scan'208";a="113252287" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2026 16:46:12 -0700 X-CSE-ConnectionGUID: DUqrzO/MSKSy9mM4HunmsA== X-CSE-MsgGUID: VZAEhUhGQ2Omc9ZvTHNbww== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,232,1779174000"; d="scan'208";a="266352334" Received: from aschende-mobl.amr.corp.intel.com (HELO [10.125.108.13]) ([10.125.108.13]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2026 16:46:10 -0700 Message-ID: <6cbd0910-533c-4167-bc30-106d532eb8af@intel.com> Date: Wed, 19 Aug 2026 16:46:09 -0700 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net 3/4] NTB: ntb_transport: Fail TX enqueue when the QP link is down To: Koichiro Den , Jon Mason , Allen Hubbe , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: ntb@lists.linux.dev, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260817053519.4135287-1-den@valinux.co.jp> <20260817053519.4135287-4-den@valinux.co.jp> From: Dave Jiang Content-Language: en-US In-Reply-To: <20260817053519.4135287-4-den@valinux.co.jp> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/16/26 10:35 PM, Koichiro Den wrote: > Commit f195a1a6fe41 ("ntb: Drop packets when qp link is down") meant to > make ntb_transport_tx_enqueue() drop packets submitted while the QP link > is down, but it only returns 0 without consuming the packet. Zero means > success by this function's contract, so ntb_netdev reports NETDEV_TX_OK > and forgets the skb: nothing queued it, nothing frees it, and it leaks, > one skb for every transmit racing a link-down. > > Return -ENOLINK instead, restoring the contract that a non-zero return > leaves the buffer owned by the caller. With the preceding patch, > ntb_netdev frees the skb on non-retryable enqueue failures and returns > NETDEV_TX_OK, so a packet racing with link-down is dropped without leaking > or entering a busy retry loop. > > Fixes: f195a1a6fe41 ("ntb: Drop packets when qp link is down") > Cc: stable@vger.kernel.org > Signed-off-by: Koichiro Den Reviewed-by: Dave Jiang > --- > drivers/ntb/ntb_transport.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c > index e92b96f4afad..4bdd81edcb87 100644 > --- a/drivers/ntb/ntb_transport.c > +++ b/drivers/ntb/ntb_transport.c > @@ -2353,9 +2353,8 @@ int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, > if (!qp || !len) > return -EINVAL; > > - /* If the qp link is down already, just ignore. */ > if (!qp->link_is_up) > - return 0; > + return -ENOLINK; > > entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); > if (!entry) {