From a349b95d7ca0cea71be4a7dac29830703de7eb62 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Tue, 27 Aug 2019 12:51:50 +0900
Subject: [PATCH] usb: host: ohci: fix a race condition between shutdown and irq
Git-commit: a349b95d7ca0cea71be4a7dac29830703de7eb62
Patch-mainline: v5.3-rc7
References: bsc#1051510
This patch fixes an issue that the following error is
possible to happen when ohci hardware causes an interruption
and the system is shutting down at the same time.
[ 34.851754] usb 2-1: USB disconnect, device number 2
[ 35.166658] irq 156: nobody cared (try booting with the "irqpoll" option)
[ 35.173445] CPU: 0 PID: 22 Comm: kworker/0:1 Not tainted 5.3.0-rc5 #85
[ 35.179964] Hardware name: Renesas Salvator-X 2nd version board based on r8a77965 (DT)
[ 35.187886] Workqueue: usb_hub_wq hub_event
[ 35.192063] Call trace:
[ 35.194509] dump_backtrace+0x0/0x150
[ 35.198165] show_stack+0x14/0x20
[ 35.201475] dump_stack+0xa0/0xc4
[ 35.204785] __report_bad_irq+0x34/0xe8
[ 35.208614] note_interrupt+0x2cc/0x318
[ 35.212446] handle_irq_event_percpu+0x5c/0x88
[ 35.216883] handle_irq_event+0x48/0x78
[ 35.220712] handle_fasteoi_irq+0xb4/0x188
[ 35.224802] generic_handle_irq+0x24/0x38
[ 35.228804] __handle_domain_irq+0x5c/0xb0
[ 35.232893] gic_handle_irq+0x58/0xa8
[ 35.236548] el1_irq+0xb8/0x180
[ 35.239681] __do_softirq+0x94/0x23c
[ 35.243253] irq_exit+0xd0/0xd8
[ 35.246387] __handle_domain_irq+0x60/0xb0
[ 35.250475] gic_handle_irq+0x58/0xa8
[ 35.254130] el1_irq+0xb8/0x180
[ 35.257268] kernfs_find_ns+0x5c/0x120
[ 35.261010] kernfs_find_and_get_ns+0x3c/0x60
[ 35.265361] sysfs_unmerge_group+0x20/0x68
[ 35.269454] dpm_sysfs_remove+0x2c/0x68
[ 35.273284] device_del+0x80/0x370
[ 35.276683] hid_destroy_device+0x28/0x60
[ 35.280686] usbhid_disconnect+0x4c/0x80
[ 35.284602] usb_unbind_interface+0x6c/0x268
[ 35.288867] device_release_driver_internal+0xe4/0x1b0
[ 35.293998] device_release_driver+0x14/0x20
[ 35.298261] bus_remove_device+0x110/0x128
[ 35.302350] device_del+0x148/0x370
[ 35.305832] usb_disable_device+0x8c/0x1d0
[ 35.309921] usb_disconnect+0xc8/0x2d0
[ 35.313663] hub_event+0x6e0/0x1128
[ 35.317146] process_one_work+0x1e0/0x320
[ 35.321148] worker_thread+0x40/0x450
[ 35.324805] kthread+0x124/0x128
[ 35.328027] ret_from_fork+0x10/0x18
[ 35.331594] handlers:
[ 35.333862] [<0000000079300c1d>] usb_hcd_irq
[ 35.338126] [<0000000079300c1d>] usb_hcd_irq
[ 35.342389] Disabling IRQ #156
ohci_shutdown() disables all the interrupt and rh_state is set to
OHCI_RH_HALTED. In other hand, ohci_irq() is possible to enable
OHCI_INTR_SF and OHCI_INTR_MIE on ohci_irq(). Note that OHCI_INTR_SF
is possible to be set by start_ed_unlink() which is called:
ohci_irq()
-> process_done_list()
-> takeback_td()
-> start_ed_unlink()
So, ohci_irq() has the following condition, the issue happens by
&ohci->regs->intrenable = OHCI_INTR_MIE | OHCI_INTR_SF and
ohci->rh_state = OHCI_RH_HALTED:
/* interrupt for some other device? */
if (ints == 0 || unlikely(ohci->rh_state == OHCI_RH_HALTED))
return IRQ_NOTMINE;
To fix the issue, ohci_shutdown() holds the spin lock while disabling
the interruption and changing the rh_state flag to prevent reenable
the OHCI_INTR_MIE unexpectedly. Note that io_watchdog_func() also
calls the ohci_shutdown() and it already held the spin lock, so that
the patch makes a new function as _ohci_shutdown().
This patch is inspired by a Renesas R-Car Gen3 BSP patch
from Tho Vu.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/1566877910-6020-1-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/host/ohci-hcd.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index b457fdaff297..1fe3deec35cf 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -419,8 +419,7 @@ static void ohci_usb_reset (struct ohci_hcd *ohci)
* other cases where the next software may expect clean state from the
* "firmware". this is bus-neutral, unlike shutdown() methods.
*/
-static void
-ohci_shutdown (struct usb_hcd *hcd)
+static void _ohci_shutdown(struct usb_hcd *hcd)
{
struct ohci_hcd *ohci;
@@ -436,6 +435,16 @@ ohci_shutdown (struct usb_hcd *hcd)
ohci->rh_state = OHCI_RH_HALTED;
}
+static void ohci_shutdown(struct usb_hcd *hcd)
+{
+ struct ohci_hcd *ohci = hcd_to_ohci(hcd);
+ unsigned long flags;
+
+ spin_lock_irqsave(&ohci->lock, flags);
+ _ohci_shutdown(hcd);
+ spin_unlock_irqrestore(&ohci->lock, flags);
+}
+
/*-------------------------------------------------------------------------*
* HC functions
*-------------------------------------------------------------------------*/
@@ -760,7 +769,7 @@ static void io_watchdog_func(struct timer_list *t)
died:
usb_hc_died(ohci_to_hcd(ohci));
ohci_dump(ohci);
- ohci_shutdown(ohci_to_hcd(ohci));
+ _ohci_shutdown(ohci_to_hcd(ohci));
goto done;
} else {
/* No write back because the done queue was empty */
--
2.16.4