From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC2BEC4332D for ; Tue, 22 Dec 2020 09:04:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81ACB23139 for ; Tue, 22 Dec 2020 09:04:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726329AbgLVJE1 (ORCPT ); Tue, 22 Dec 2020 04:04:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725852AbgLVJEZ (ORCPT ); Tue, 22 Dec 2020 04:04:25 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 046F7C0613D6; Tue, 22 Dec 2020 01:03:45 -0800 (PST) From: "Ahmed S. Darwish" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1608627823; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nZBSK9mHHNtLwhuezSj8NTtR1rI43yzR6gjfd6ON5EU=; b=cvsr2PwEE902RUmjdHG2i/27Ajjulrr6nL3bXq8WtmQYLFGGOZoJHjeFW5SG4XkyNoiNGX dtTRkZE0Lrt4bg0waFNEXITkTAhl4MZqvItnEuMGkIhxG/9TncwAXVueUgzFjGRtG7WQFi lKXaEOq3WWoLSYgduCm4T/HXACToUP20Nt6qZ0SXEgaKH/YtCDiG5qy38MmzQ/UTE63vjd zz7n3mqUCuYUHeUN2pKqn/tXxfLmjJmVo29x2M9EnzGYc89AvZWMQxE2R92SFlwCB95Jjc 7FmKTtcTq1V4FYLSwmcFMptUzJC7fWX+Qagdn3PdM5WM6h1XIBNpC1WLzn6W2w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1608627823; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nZBSK9mHHNtLwhuezSj8NTtR1rI43yzR6gjfd6ON5EU=; b=AHbfLavfitPM+M9S7BKsplKpkIlnsHkyuZ9tfxyn2QfiYVt/JSYO/upZcahqaKZ5RvScao wonlDffsKpocQZBA== To: Michael Grzeschik , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org Cc: LKML , Thomas Gleixner , "Sebastian A. Siewior" , "Ahmed S. Darwish" Subject: [RFC PATCH 1/1] net: arcnet: Fix RESET flag handling Date: Tue, 22 Dec 2020 10:03:38 +0100 Message-Id: <20201222090338.186503-2-a.darwish@linutronix.de> In-Reply-To: <20201222090338.186503-1-a.darwish@linutronix.de> References: <20201222090338.186503-1-a.darwish@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The main arcnet interrupt handler calls arcnet_close() then arcnet_open(), if the RESET status flag is encountered. This is invalid: 1) In general, interrupt handlers should never call ->ndo_stop() and ->ndo_open() functions. They are usually full of blocking calls and other methods that are expected to be called only from drivers init and exit code paths. 2) arcnet_close() contains a del_timer_sync(). If the irq handler interrupts the to-be-deleted timer, del_timer_sync() will just loop forever. 3) arcnet_close() also calls tasklet_kill(), which has a warning if called from irq context. 4) For device reset, the sequence "arcnet_close(); arcnet_open();" is not complete. Some children arcnet drivers have special init/exit code sequences, which then embed a call to arcnet_open() and arcnet_close() accordingly. Check drivers/net/arcnet/com20020.c. Run the device RESET sequence from a scheduled workqueue instead. Signed-off-by: Ahmed S. Darwish --- drivers/net/arcnet/arc-rimi.c | 4 +- drivers/net/arcnet/arcdevice.h | 6 +++ drivers/net/arcnet/arcnet.c | 69 +++++++++++++++++++++++++++++-- drivers/net/arcnet/com20020-isa.c | 4 +- drivers/net/arcnet/com20020-pci.c | 2 +- drivers/net/arcnet/com20020_cs.c | 2 +- drivers/net/arcnet/com90io.c | 4 +- drivers/net/arcnet/com90xx.c | 4 +- 8 files changed, 81 insertions(+), 14 deletions(-) diff --git a/drivers/net/arcnet/arc-rimi.c b/drivers/net/arcnet/arc-rimi.c index 98df38fe553c..12d085405bd0 100644 --- a/drivers/net/arcnet/arc-rimi.c +++ b/drivers/net/arcnet/arc-rimi.c @@ -332,7 +332,7 @@ static int __init arc_rimi_init(void) dev->irq = 9; if (arcrimi_probe(dev)) { - free_netdev(dev); + free_arcdev(dev); return -EIO; } @@ -349,7 +349,7 @@ static void __exit arc_rimi_exit(void) iounmap(lp->mem_start); release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1); free_irq(dev->irq, dev); - free_netdev(dev); + free_arcdev(dev); } #ifndef MODULE diff --git a/drivers/net/arcnet/arcdevice.h b/drivers/net/arcnet/arcdevice.h index 22a49c6d7ae6..5d4a4c7efbbf 100644 --- a/drivers/net/arcnet/arcdevice.h +++ b/drivers/net/arcnet/arcdevice.h @@ -298,6 +298,10 @@ struct arcnet_local { int excnak_pending; /* We just got an excesive nak interrupt */ + /* RESET flag handling */ + int reset_in_progress; + struct work_struct reset_work; + struct { uint16_t sequence; /* sequence number (incs with each packet) */ __be16 aborted_seq; @@ -350,7 +354,9 @@ void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc) void arcnet_unregister_proto(struct ArcProto *proto); irqreturn_t arcnet_interrupt(int irq, void *dev_id); + struct net_device *alloc_arcdev(const char *name); +void free_arcdev(struct net_device *dev); int arcnet_open(struct net_device *dev); int arcnet_close(struct net_device *dev); diff --git a/drivers/net/arcnet/arcnet.c b/drivers/net/arcnet/arcnet.c index e04efc0a5c97..563c43ae5cce 100644 --- a/drivers/net/arcnet/arcnet.c +++ b/drivers/net/arcnet/arcnet.c @@ -387,10 +387,46 @@ static void arcnet_timer(struct timer_list *t) struct arcnet_local *lp = from_timer(lp, t, timer); struct net_device *dev = lp->dev; - if (!netif_carrier_ok(dev)) { + spin_lock_irq(&lp->lock); + + if (!lp->reset_in_progress && !netif_carrier_ok(dev)) { netif_carrier_on(dev); netdev_info(dev, "link up\n"); } + + spin_unlock_irq(&lp->lock); +} + +static void reset_device_work(struct work_struct *work) +{ + struct arcnet_local *lp; + struct net_device *dev; + + lp = container_of(work, struct arcnet_local, reset_work); + dev = lp->dev; + + /* + * Do not bring the network interface back up if an ifdown + * was already done. + */ + if (!netif_running(dev) || !lp->reset_in_progress) + return; + + rtnl_lock(); + + /* + * Do another check, in case of an ifdown that was triggered in + * the small race window between the exit condition above and + * acquiring RTNL. + */ + if (!netif_running(dev) || !lp->reset_in_progress) + goto out; + + dev_close(dev); + dev_open(dev, NULL); + +out: + rtnl_unlock(); } static void arcnet_reply_tasklet(unsigned long data) @@ -452,12 +488,26 @@ struct net_device *alloc_arcdev(const char *name) lp->dev = dev; spin_lock_init(&lp->lock); timer_setup(&lp->timer, arcnet_timer, 0); + INIT_WORK(&lp->reset_work, reset_device_work); } return dev; } EXPORT_SYMBOL(alloc_arcdev); +void free_arcdev(struct net_device *dev) +{ + struct arcnet_local *lp = netdev_priv(dev); + + /* + * Do not cancel this at ->ndo_close(), as the workqueue itself + * indirectly calls the ifdown path through dev_close(). + */ + cancel_work_sync(&lp->reset_work); + free_netdev(dev); +} +EXPORT_SYMBOL(free_arcdev); + /* Open/initialize the board. This is called sometime after booting when * the 'ifconfig' program is run. * @@ -587,6 +637,10 @@ int arcnet_close(struct net_device *dev) /* shut down the card */ lp->hw.close(dev); + + /* reset counters */ + lp->reset_in_progress = 0; + module_put(lp->hw.owner); return 0; } @@ -820,6 +874,9 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id) spin_lock_irqsave(&lp->lock, flags); + if (lp->reset_in_progress) + goto out; + /* RESET flag was enabled - if device is not running, we must * clear it right away (but nothing else). */ @@ -852,11 +909,14 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id) if (status & RESETflag) { arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n", status); - arcnet_close(dev); - arcnet_open(dev); + + lp->reset_in_progress = 1; + netif_stop_queue(dev); + netif_carrier_off(dev); + schedule_work(&lp->reset_work); /* get out of the interrupt handler! */ - break; + goto out; } /* RX is inhibited - we must have received something. * Prepare to receive into the next buffer. @@ -1052,6 +1112,7 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id) udelay(1); lp->hw.intmask(dev, lp->intmask); +out: spin_unlock_irqrestore(&lp->lock, flags); return retval; } diff --git a/drivers/net/arcnet/com20020-isa.c b/drivers/net/arcnet/com20020-isa.c index f983c4ce6b07..b50d4c33d2a4 100644 --- a/drivers/net/arcnet/com20020-isa.c +++ b/drivers/net/arcnet/com20020-isa.c @@ -169,7 +169,7 @@ static int __init com20020_init(void) dev->irq = 9; if (com20020isa_probe(dev)) { - free_netdev(dev); + free_arcdev(dev); return -EIO; } @@ -182,7 +182,7 @@ static void __exit com20020_exit(void) unregister_netdev(my_dev); free_irq(my_dev->irq, my_dev); release_region(my_dev->base_addr, ARCNET_TOTAL_SIZE); - free_netdev(my_dev); + free_ardev(my_dev); } #ifndef MODULE diff --git a/drivers/net/arcnet/com20020-pci.c b/drivers/net/arcnet/com20020-pci.c index eb7f76753c9c..8bdc44b7e09a 100644 --- a/drivers/net/arcnet/com20020-pci.c +++ b/drivers/net/arcnet/com20020-pci.c @@ -291,7 +291,7 @@ static void com20020pci_remove(struct pci_dev *pdev) unregister_netdev(dev); free_irq(dev->irq, dev); - free_netdev(dev); + free_arcdev(dev); } } diff --git a/drivers/net/arcnet/com20020_cs.c b/drivers/net/arcnet/com20020_cs.c index cf607ffcf358..9cc5eb6a8e90 100644 --- a/drivers/net/arcnet/com20020_cs.c +++ b/drivers/net/arcnet/com20020_cs.c @@ -177,7 +177,7 @@ static void com20020_detach(struct pcmcia_device *link) dev = info->dev; if (dev) { dev_dbg(&link->dev, "kfree...\n"); - free_netdev(dev); + free_arcdev(dev); } dev_dbg(&link->dev, "kfree2...\n"); kfree(info); diff --git a/drivers/net/arcnet/com90io.c b/drivers/net/arcnet/com90io.c index cf214b730671..3856b447d38e 100644 --- a/drivers/net/arcnet/com90io.c +++ b/drivers/net/arcnet/com90io.c @@ -396,7 +396,7 @@ static int __init com90io_init(void) err = com90io_probe(dev); if (err) { - free_netdev(dev); + free_arcdev(dev); return err; } @@ -419,7 +419,7 @@ static void __exit com90io_exit(void) free_irq(dev->irq, dev); release_region(dev->base_addr, ARCNET_TOTAL_SIZE); - free_netdev(dev); + free_arcdev(dev); } module_init(com90io_init) diff --git a/drivers/net/arcnet/com90xx.c b/drivers/net/arcnet/com90xx.c index 3dc3d533cb19..d8dfb9ea0de8 100644 --- a/drivers/net/arcnet/com90xx.c +++ b/drivers/net/arcnet/com90xx.c @@ -554,7 +554,7 @@ static int __init com90xx_found(int ioaddr, int airq, u_long shmem, err_release_mem: release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1); err_free_dev: - free_netdev(dev); + free_arcdev(dev); return -EIO; } @@ -672,7 +672,7 @@ static void __exit com90xx_exit(void) release_region(dev->base_addr, ARCNET_TOTAL_SIZE); release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1); - free_netdev(dev); + free_arcdev(dev); } } -- 2.29.2