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 9B8258615A; Tue, 17 Dec 2024 17:29:48 +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=1734456588; cv=none; b=pPi6jRbPOWLKenXPE6hZFB7y/mCN4zCUiDRbBA1f8jb3CedNkrN4JlP1WSLV6IHpjGJKoukNuEHtHnmmq9ab/h0R4hN38E0ZEDjrdREz9ObO8UDAHsqFddQRjs0dEKip/b5G1hl/UP9/P5PO4CcVm4ZKmo25c0b2/2E1qP/E7qI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734456588; c=relaxed/simple; bh=WCa8DwNU32IAbUQiW41C3U4R7VtOdTRbbAED5HWCYjo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JFikgW86SwiocodXWH5FHT+Mo/sTFVSU504G0OhlcO3rCKRiB9t7HnnCipMl9fJqYAJsJ7Rk9ANd+Z/YtsfzM9etAn2jk+hPEXlsdPRoHPbNUfvJB7orA2GX8RUq1o1tpvdK7h3Qg72+NNhToDpSG4mPDNvFY0kCPuiTiERqWiE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=fahz++xr; 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="fahz++xr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20F67C4CED7; Tue, 17 Dec 2024 17:29:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1734456588; bh=WCa8DwNU32IAbUQiW41C3U4R7VtOdTRbbAED5HWCYjo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fahz++xr3GSlBZV1vJL8cmf+NlHfdsXOoWmXULAvkL1ex64MT/azImk9G+8G6zvAa IBfwudiZNl57MyzRTAWWs2yPGWOmh9EfsUukMiiqAOkyaqjzz2LEImYAhkXumbpDWA RTfwKtntaEdYBH3ZjqIob4AvEmti2P4ZBG8gWgDY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vladimir Oltean , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 105/172] net: mscc: ocelot: ocelot->ts_id_lock and ocelot_port->tx_skbs.lock are IRQ-safe Date: Tue, 17 Dec 2024 18:07:41 +0100 Message-ID: <20241217170550.684764846@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241217170546.209657098@linuxfoundation.org> References: <20241217170546.209657098@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vladimir Oltean [ Upstream commit 0c53cdb95eb4a604062e326636971d96dd9b1b26 ] ocelot_get_txtstamp() is a threaded IRQ handler, requested explicitly as such by both ocelot_ptp_rdy_irq_handler() and vsc9959_irq_handler(). As such, it runs with IRQs enabled, and not in hardirq context. Thus, ocelot_port_add_txtstamp_skb() has no reason to turn off IRQs, it cannot be preempted by ocelot_get_txtstamp(). For the same reason, dev_kfree_skb_any_reason() will always evaluate as kfree_skb_reason() in this calling context, so just simplify the dev_kfree_skb_any() call to kfree_skb(). Also, ocelot_port_txtstamp_request() runs from NET_TX softirq context, not with hardirqs enabled. Thus, ocelot_get_txtstamp() which shares the ocelot_port->tx_skbs.lock lock with it, has no reason to disable hardirqs. This is part of a larger rework of the TX timestamping procedure. A logical subportion of the rework has been split into a separate change. Signed-off-by: Vladimir Oltean Link: https://patch.msgid.link/20241205145519.1236778-4-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski Stable-dep-of: b454abfab525 ("net: mscc: ocelot: be resilient to loss of PTP packets during transmission") Signed-off-by: Sasha Levin --- drivers/net/ethernet/mscc/ocelot_ptp.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/mscc/ocelot_ptp.c b/drivers/net/ethernet/mscc/ocelot_ptp.c index 95a5267bc9ce..d732f99e6391 100644 --- a/drivers/net/ethernet/mscc/ocelot_ptp.c +++ b/drivers/net/ethernet/mscc/ocelot_ptp.c @@ -607,13 +607,12 @@ static int ocelot_port_add_txtstamp_skb(struct ocelot *ocelot, int port, struct sk_buff *clone) { struct ocelot_port *ocelot_port = ocelot->ports[port]; - unsigned long flags; - spin_lock_irqsave(&ocelot->ts_id_lock, flags); + spin_lock(&ocelot->ts_id_lock); if (ocelot_port->ptp_skbs_in_flight == OCELOT_MAX_PTP_ID || ocelot->ptp_skbs_in_flight == OCELOT_PTP_FIFO_SIZE) { - spin_unlock_irqrestore(&ocelot->ts_id_lock, flags); + spin_unlock(&ocelot->ts_id_lock); return -EBUSY; } @@ -630,7 +629,7 @@ static int ocelot_port_add_txtstamp_skb(struct ocelot *ocelot, int port, skb_queue_tail(&ocelot_port->tx_skbs, clone); - spin_unlock_irqrestore(&ocelot->ts_id_lock, flags); + spin_unlock(&ocelot->ts_id_lock); return 0; } @@ -749,7 +748,6 @@ void ocelot_get_txtstamp(struct ocelot *ocelot) u32 val, id, seqid, txport; struct ocelot_port *port; struct timespec64 ts; - unsigned long flags; val = ocelot_read(ocelot, SYS_PTP_STATUS); @@ -773,7 +771,7 @@ void ocelot_get_txtstamp(struct ocelot *ocelot) /* Retrieve its associated skb */ try_again: - spin_lock_irqsave(&port->tx_skbs.lock, flags); + spin_lock(&port->tx_skbs.lock); skb_queue_walk_safe(&port->tx_skbs, skb, skb_tmp) { if (OCELOT_SKB_CB(skb)->ts_id != id) @@ -783,7 +781,7 @@ void ocelot_get_txtstamp(struct ocelot *ocelot) break; } - spin_unlock_irqrestore(&port->tx_skbs.lock, flags); + spin_unlock(&port->tx_skbs.lock); if (WARN_ON(!skb_match)) goto next_ts; @@ -792,7 +790,7 @@ void ocelot_get_txtstamp(struct ocelot *ocelot) dev_err_ratelimited(ocelot->dev, "port %d received stale TX timestamp for seqid %d, discarding\n", txport, seqid); - dev_kfree_skb_any(skb); + kfree_skb(skb); goto try_again; } -- 2.39.5