diff options
| author | John Stultz <john.stultz@linaro.org> | 2017-01-23 14:59:14 -0800 |
|---|---|---|
| committer | Felipe Balbi <felipe.balbi@linux.intel.com> | 2017-01-24 16:19:08 +0200 |
| commit | 6e6360b67d12370638ad1bc8943cc63d4c89da27 (patch) | |
| tree | 341fc06bd363a75182facd22292b6189bb6f885d /drivers/usb/dwc2 | |
| parent | 2124f9e673124b72fdbd2d534526ab76f0771766 (diff) | |
| download | linux-6e6360b67d12370638ad1bc8943cc63d4c89da27.tar.bz2 | |
usb: dwc2: Avoid sleeping while holding hsotg->lock
Basically when plugging in various cables in different orders, I'm
occasionally seeing the following BUG splat:
[ 86.215403] BUG: scheduling while atomic: kworker/u16:2/53/0x00000002
[ 86.219164] usb 1-1: USB disconnect, device number 9
[ 86.226845] Preemption disabled at:[ 86.230218]
[<ffffff8008673558>] dwc2_conn_id_status_change+0x120/0x250
[ 86.236894] CPU: 0 PID: 53 Comm: kworker/u16:2 Tainted: G W
4.9.0-rc8-00051-gd5a7979-dirty #1702
[ 86.246836] Hardware name: HiKey Development Board (DT)
[ 86.252100] Workqueue: dwc2 dwc2_conn_id_status_change
[ 86.257279] Call trace:
[ 86.259771] [<ffffff8008087c28>] dump_backtrace+0x0/0x1a0
[ 86.265210] [<ffffff8008087ddc>] show_stack+0x14/0x20
[ 86.270308] [<ffffff80084343f0>] dump_stack+0x90/0xb0
[ 86.275401] [<ffffff80080d8d94>] __schedule_bug+0x6c/0xb8
[ 86.280841] [<ffffff8008a07220>] __schedule+0x4f8/0x5b0
[ 86.286099] [<ffffff8008a073e8>] schedule+0x38/0xa0
[ 86.291017] [<ffffff8008a0a6cc>] schedule_hrtimeout_range_clock+0x8c/0xf0
[ 86.297846] [<ffffff8008a0a740>] schedule_hrtimeout_range+0x10/0x18
[ 86.304150] [<ffffff8008a0a4a0>] usleep_range+0x50/0x58
[ 86.309418] [<ffffff800866d8dc>] dwc2_wait_for_mode.isra.4+0x54/0xd0
[ 86.315815] [<ffffff800866f058>] dwc2_core_reset+0xe0/0x168
[ 86.321431] [<ffffff800867e364>] dwc2_hsotg_core_init_disconnected+0x2c/0x310
[ 86.328602] [<ffffff8008673568>] dwc2_conn_id_status_change+0x130/0x250
[ 86.335254] [<ffffff80080ccd48>] process_one_work+0x118/0x370
[ 86.341035] [<ffffff80080ccfe8>] worker_thread+0x48/0x498
[ 86.346473] [<ffffff80080d2eb0>] kthread+0xd0/0xe8
[ 86.351299] [<ffffff8008082e80>] ret_from_fork+0x10/0x50
This seems to be caused by the dwc2_wait_for_mode() calling
usleep_range() while the hstog->lock spinlock is held, since
we take that before calling dwc2_hsotg_core_init_disconnected().
This patch avoids the issue by adding an extra argument to
dwc2_core_reset(), as suggested by John Youn, which allows us to
skip the waiting, which should be unnecessary when calling from
dwc2_hsotg_core_init_disconnected().
Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Guodong Xu <guodong.xu@linaro.org>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: John Youn <johnyoun@synopsys.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Chen Yu <chenyu56@huawei.com>
Cc: Vardan Mikayelyan <mvardan@synopsys.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Diffstat (limited to 'drivers/usb/dwc2')
| -rw-r--r-- | drivers/usb/dwc2/core.c | 6 | ||||
| -rw-r--r-- | drivers/usb/dwc2/core.h | 2 | ||||
| -rw-r--r-- | drivers/usb/dwc2/gadget.c | 2 |
3 files changed, 5 insertions, 5 deletions
diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c index c987547a1e7b..7195366e26bf 100644 --- a/drivers/usb/dwc2/core.c +++ b/drivers/usb/dwc2/core.c @@ -313,7 +313,7 @@ static bool dwc2_iddig_filter_enabled(struct dwc2_hsotg *hsotg) * Do core a soft reset of the core. Be careful with this because it * resets all the internal state machines of the core. */ -int dwc2_core_reset(struct dwc2_hsotg *hsotg) +int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait) { u32 greset; int count = 0; @@ -369,7 +369,7 @@ int dwc2_core_reset(struct dwc2_hsotg *hsotg) } } while (!(greset & GRSTCTL_AHBIDLE)); - if (wait_for_host_mode) + if (wait_for_host_mode && !skip_wait) dwc2_wait_for_mode(hsotg, true); return 0; @@ -500,7 +500,7 @@ int dwc2_core_reset_and_force_dr_mode(struct dwc2_hsotg *hsotg) { int retval; - retval = dwc2_core_reset(hsotg); + retval = dwc2_core_reset(hsotg, false); if (retval) return retval; diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index 2bd3ea624cfc..b07bf7be2034 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -1088,7 +1088,7 @@ static inline bool dwc2_is_hs_iot(struct dwc2_hsotg *hsotg) * The following functions support initialization of the core driver component * and the DWC_otg controller */ -int dwc2_core_reset(struct dwc2_hsotg *hsotg); +int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait); int dwc2_core_reset_and_force_dr_mode(struct dwc2_hsotg *hsotg); int dwc2_enter_hibernation(struct dwc2_hsotg *hsotg); int dwc2_exit_hibernation(struct dwc2_hsotg *hsotg, bool restore); diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c index 1a1355429c1a..30ff51eab35c 100644 --- a/drivers/usb/dwc2/gadget.c +++ b/drivers/usb/dwc2/gadget.c @@ -3164,7 +3164,7 @@ void dwc2_hsotg_core_init_disconnected(struct dwc2_hsotg *hsotg, kill_all_requests(hsotg, hsotg->eps_out[0], -ECONNRESET); if (!is_usb_reset) - if (dwc2_core_reset(hsotg)) + if (dwc2_core_reset(hsotg, true)) return; /* |