[PATCH] net: usb: lan78xx: Disable interrupts before calling generic_handle_irq()

lan78xx_status() will run with interrupts enabled due to the change in
ed194d136769 ("usb: core: remove local_irq_save() around ->complete()
handler"). generic_handle_irq() expects to be run with IRQs disabled.

[    4.886203] 000: irq 79 handler irq_default_primary_handler+0x0/0x8 enabled interrupts
[    4.886243] 000: WARNING: CPU: 0 PID: 0 at kernel/irq/handle.c:152 __handle_irq_event_percpu+0x154/0x168
[    4.896294] 000: Modules linked in:
[    4.896301] 000: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.6 #39
[    4.896310] 000: Hardware name: Raspberry Pi 3 Model B+ (DT)
[    4.896315] 000: pstate: 60000005 (nZCv daif -PAN -UAO)
[    4.896321] 000: pc : __handle_irq_event_percpu+0x154/0x168
[    4.896331] 000: lr : __handle_irq_event_percpu+0x154/0x168
[    4.896339] 000: sp : ffff000010003cc0
[    4.896346] 000: x29: ffff000010003cc0 x28: 0000000000000060
[    4.896355] 000: x27: ffff000011021980 x26: ffff00001189c72b
[    4.896364] 000: x25: ffff000011702bc0 x24: ffff800036d6e400
[    4.896373] 000: x23: 000000000000004f x22: ffff000010003d64
[    4.896381] 000: x21: 0000000000000000 x20: 0000000000000002
[    4.896390] 000: x19: ffff8000371c8480 x18: 0000000000000060
[    4.896398] 000: x17: 0000000000000000 x16: 00000000000000eb
[    4.896406] 000: x15: ffff000011712d18 x14: 7265746e69206465
[    4.896414] 000: x13: ffff000010003ba0 x12: ffff000011712df0
[    4.896422] 000: x11: 0000000000000001 x10: ffff000011712e08
[    4.896430] 000: x9 : 0000000000000001 x8 : 000000000003c920
[    4.896437] 000: x7 : ffff0000118cc410 x6 : ffff0000118c7f00
[    4.896445] 000: x5 : 000000000003c920 x4 : 0000000000004510
[    4.896453] 000: x3 : ffff000011712dc8 x2 : 0000000000000000
[    4.896461] 000: x1 : 73a3f67df94c1500 x0 : 0000000000000000
[    4.896466] 000: Call trace:
[    4.896471] 000:  __handle_irq_event_percpu+0x154/0x168
[    4.896481] 000:  handle_irq_event_percpu+0x50/0xb0
[    4.896489] 000:  handle_irq_event+0x40/0x98
[    4.896497] 000:  handle_simple_irq+0xa4/0xf0
[    4.896505] 000:  generic_handle_irq+0x24/0x38
[    4.896513] 000:  intr_complete+0xb0/0xe0
[    4.896525] 000:  __usb_hcd_giveback_urb+0x58/0xd8
[    4.896533] 000:  usb_giveback_urb_bh+0xd0/0x170
[    4.896539] 000:  tasklet_action_common.isra.0+0x9c/0x128
[    4.896549] 000:  tasklet_hi_action+0x24/0x30
[    4.896556] 000:  __do_softirq+0x120/0x23c
[    4.896564] 000:  irq_exit+0xb8/0xd8
[    4.896571] 000:  __handle_domain_irq+0x64/0xb8
[    4.896579] 000:  bcm2836_arm_irqchip_handle_irq+0x60/0xc0
[    4.896586] 000:  el1_irq+0xb8/0x140
[    4.896592] 000:  arch_cpu_idle+0x10/0x18
[    4.896601] 000:  do_idle+0x200/0x280
[    4.896608] 000:  cpu_startup_entry+0x20/0x28
[    4.896615] 000:  rest_init+0xb4/0xc0
[    4.896623] 000:  arch_call_rest_init+0xc/0x14
[    4.896632] 000:  start_kernel+0x454/0x480

Fixes: ed194d136769 ("usb: core: remove local_irq_save() around ->complete() handler")
Cc: Woojung Huh <woojung.huh@microchip.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Stefan Wahren <wahrenst@gmx.net>
Cc: Jisheng Zhang <redacted>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <redacted>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Daniel Wagner <redacted>
---

Hi,

This patch just fixes the warning. There are still problems left (the
unstable NFS report from me) but I suggest to look at this
separately. The initial patch to revert all the irqdomain code might
just hide the problem. At this point I don't know what's going on so I
rather go baby steps. The revert is still possible if nothing else
works.

Thanks,
Daniel

 drivers/net/usb/lan78xx.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 62948098191f..f24a1b0b801f 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c

@@ -1264,8 +1264,11 @@ static void lan78xx_status(struct lan78xx_net *dev, struct urb *urb)
 		netif_dbg(dev, link, dev->net, "PHY INTR: 0x%08x\n", intdata);
 		lan78xx_defer_kevent(dev, EVENT_LINK_RESET);
 
-		if (dev->domain_data.phyirq > 0)
+		if (dev->domain_data.phyirq > 0) {
+			local_irq_disable();
 			generic_handle_irq(dev->domain_data.phyirq);
+			local_irq_enable();
+		}
 	} else
 		netdev_warn(dev->net,
 			    "unexpected interrupt: 0x%08x\n", intdata);

-- 
2.23.0

Hi Daniel,

Am 25.10.19 um 10:04 schrieb Daniel Wagner:

...

Fixes: ed194d136769 ("usb: core: remove local_irq_save() around ->complete() handler")
Cc: Woojung Huh <woojung.huh@microchip.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Stefan Wahren <wahrenst@gmx.net>
Cc: Jisheng Zhang <redacted>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <redacted>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Daniel Wagner <redacted>
---

Hi,

This patch just fixes the warning. There are still problems left (the
unstable NFS report from me) but I suggest to look at this
separately. The initial patch to revert all the irqdomain code might
just hide the problem. At this point I don't know what's going on so I
rather go baby steps. The revert is still possible if nothing else
works.

did you ever see this pseudo lan78xx-irqs fire? I examined
/proc/interrupts on RPi 3B+ and always saw a 0.

FWIW you can have:

Tested-by: Stefan Wahren <wahrenst@gmx.net>

for this patch.

Regards
Stefan

From: Daniel Wagner <redacted>
Date: Fri, 25 Oct 2019 10:04:13 +0200

lan78xx_status() will run with interrupts enabled due to the change in
ed194d136769 ("usb: core: remove local_irq_save() around ->complete()
handler"). generic_handle_irq() expects to be run with IRQs disabled.

 ...

Fixes: ed194d136769 ("usb: core: remove local_irq_save() around ->complete() handler")

 ...

Signed-off-by: Daniel Wagner <redacted>

Applied and queued up for -stable, thanks Daniel.

Hi Stefan,

On Sun, Oct 27, 2019 at 01:14:41PM +0100, Stefan Wahren wrote:

did you ever see this pseudo lan78xx-irqs fire? I examined
/proc/interrupts on RPi 3B+ and always saw a 0.

# cat /proc/interrupts 
           CPU0       CPU1       CPU2       CPU3       
  2:         15         10         20         14  ARMCTRL-level   1 Edge      3f00b880.mailbox
 41:     127709     127690     127596     127783  ARMCTRL-level  41 Edge      3f980000.usb, dwc2_hsotg:usb1
 61:        219        208        183        192  ARMCTRL-level  61 Edge      ttyS1
 65:       1285       1340       2112       1483  ARMCTRL-level  88 Edge      mmc0
 71:         11         15         13         13  ARMCTRL-level  94 Edge      mmc1
147:       2823       2995       3648       3615  bcm2836-timer   1 Edge      arch_timer
148:          0          0          0          0  bcm2836-timer   3 Edge      kvm guest timer
150:          0          1          2          0  lan78xx-irqs  17 Edge      usb-001:004:01
IPI0:     11102      11331      12204      11011       Rescheduling interrupts
IPI1:        34        537        547        523       Function call interrupts
IPI2:         0          0          0          0       CPU stop interrupts
IPI3:         0          0          0          0       CPU stop (for crash dump) interrupts
IPI4:         0          0          0          0       Timer broadcast interrupts
IPI5:         0          0          0          0       IRQ work interrupts
IPI6:         0          0          0          0       CPU wake-up interrupts


Yes, this seems to work now fine with the current version. 

Thanks,
Daniel

On Fri, Oct 25, 2019 at 10:04:13AM +0200, Daniel Wagner wrote:

This patch just fixes the warning. There are still problems left (the
unstable NFS report from me) but I suggest to look at this
separately. The initial patch to revert all the irqdomain code might
just hide the problem. At this point I don't know what's going on so I
rather go baby steps. The revert is still possible if nothing else
works.

I replaced my power supply with the official RPi one and the NFS
timeouts problems are gone. Also a long test session with different
network loads didn't show any problems. I feel so stupid...

Thanks,
Daniel

Hi Daniel,

Am 04.11.19 um 09:57 schrieb Daniel Wagner:

On Fri, Oct 25, 2019 at 10:04:13AM +0200, Daniel Wagner wrote:

quoted

This patch just fixes the warning. There are still problems left (the
unstable NFS report from me) but I suggest to look at this
separately. The initial patch to revert all the irqdomain code might
just hide the problem. At this point I don't know what's going on so I
rather go baby steps. The revert is still possible if nothing else
works.

I replaced my power supply with the official RPi one and the NFS
timeouts problems are gone. Also a long test session with different
network loads didn't show any problems. I feel so stupid...

did you never saw a warning about under voltage from the Raspberry Pi
hwmon driver?

Thanks,
Daniel

did you never saw a warning about under voltage from the Raspberry Pi
hwmon driver?

Guess why I feel so stupid? I just ignored it... /me goes back to
shaming in the corner.