4.19-stable review patch. If anyone has any objections, please let me know.
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From: Ahmed S. Darwish a.darwish@linutronix.de
[ Upstream commit 01365633bd1c836240f9bbf86bbeee749795480a ]
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 a.darwish@linutronix.de Signed-off-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Link: https://lore.kernel.org/r/20210128194802.727770-1-a.darwish@linutronix.de Signed-off-by: Jakub Kicinski kuba@kernel.org Stable-dep-of: 6b17a597fc2f ("arcnet: restoring support for multiple Sohard Arcnet cards") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/arcnet/arc-rimi.c | 4 +- drivers/net/arcnet/arcdevice.h | 6 +++ drivers/net/arcnet/arcnet.c | 66 +++++++++++++++++++++++++++++++++++--- 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, 78 insertions(+), 14 deletions(-)
--- 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 --- a/drivers/net/arcnet/arcdevice.h +++ b/drivers/net/arcnet/arcdevice.h @@ -303,6 +303,10 @@ 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; @@ -355,7 +359,9 @@ void arcnet_dump_skb(struct net_device *
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); --- a/drivers/net/arcnet/arcnet.c +++ b/drivers/net/arcnet/arcnet.c @@ -387,10 +387,44 @@ static void arcnet_timer(struct timer_li 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); + +out: + rtnl_unlock(); }
static void arcnet_reply_tasklet(unsigned long data) @@ -452,12 +486,25 @@ struct net_device *alloc_arcdev(const ch 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 +634,10 @@ 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 +871,9 @@ irqreturn_t arcnet_interrupt(int irq, vo
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 +906,14 @@ irqreturn_t arcnet_interrupt(int irq, vo 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 +1109,7 @@ irqreturn_t arcnet_interrupt(int irq, vo udelay(1); lp->hw.intmask(dev, lp->intmask);
+out: spin_unlock_irqrestore(&lp->lock, flags); return retval; } --- 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_arcdev(my_dev); }
#ifndef MODULE --- a/drivers/net/arcnet/com20020-pci.c +++ b/drivers/net/arcnet/com20020-pci.c @@ -294,7 +294,7 @@ static void com20020pci_remove(struct pc
unregister_netdev(dev); free_irq(dev->irq, dev); - free_netdev(dev); + free_arcdev(dev); } }
--- a/drivers/net/arcnet/com20020_cs.c +++ b/drivers/net/arcnet/com20020_cs.c @@ -177,7 +177,7 @@ static void com20020_detach(struct pcmci 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); --- a/drivers/net/arcnet/com90io.c +++ b/drivers/net/arcnet/com90io.c @@ -394,7 +394,7 @@ static int __init com90io_init(void) err = com90io_probe(dev);
if (err) { - free_netdev(dev); + free_arcdev(dev); return err; }
@@ -417,7 +417,7 @@ 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) --- a/drivers/net/arcnet/com90xx.c +++ b/drivers/net/arcnet/com90xx.c @@ -554,7 +554,7 @@ err_free_irq: 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); } }