linux/drivers/usb/dwc3
Sebastian Andrzej Siewior 84918a89d6 usb: dwc3: gadget: Let the interrupt handler disable bottom halves.
The interrupt service routine registered for the gadget is a primary
handler which mask the interrupt source and a threaded handler which
handles the source of the interrupt. Since the threaded handler is
voluntary threaded, the IRQ-core does not disable bottom halves before
invoke the handler like it does for the forced-threaded handler.

Due to changes in networking it became visible that a network gadget's
completions handler may schedule a softirq which remains unprocessed.
The gadget's completion handler is usually invoked either in hard-IRQ or
soft-IRQ context. In this context it is enough to just raise the softirq
because the softirq itself will be handled once that context is left.
In the case of the voluntary threaded handler, there is nothing that
will process pending softirqs. Which means it remain queued until
another random interrupt (on this CPU) fires and handles it on its exit
path or another thread locks and unlocks a lock with the bh suffix.
Worst case is that the CPU goes idle and the NOHZ complains about
unhandled softirqs.

Disable bottom halves before acquiring the lock (and disabling
interrupts) and enable them after dropping the lock. This ensures that
any pending softirqs will handled right away.

Link: https://lkml.kernel.org/r/c2a64979-73d1-2c22-e048-c275c9f81558@samsung.com
Fixes: e5f68b4a3e ("Revert "usb: dwc3: gadget: remove unnecessary _irqsave()"")
Cc: stable <stable@kernel.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/Yg/YPejVQH3KkRVd@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-24 11:16:38 +01:00
..
core.c usb: dwc3: leave default DMA for PCI devices 2021-11-17 15:03:51 +01:00
core.h usb: dwc3: gadget: Support Multi-Stream Transfer 2021-12-13 14:56:37 +01:00
debug.h usb: dwc3: debugfs: Add and remove endpoint dirs dynamically 2021-06-03 20:28:23 +02:00
debugfs.c USB: dwc3: remove debugfs root dentry storage 2021-06-10 19:57:21 +02:00
drd.c usb: dwc3: drd: use helper to get role-switch-default-mode 2021-07-27 15:58:37 +02:00
dwc3-exynos.c usb: dwc3: exynos: fix incorrect kernel-doc comment syntax 2021-04-02 15:20:54 +02:00
dwc3-haps.c usb: dwc3: haps: Constify the software node 2021-02-04 15:42:06 +01:00
dwc3-imx8mp.c usb: dwc3: imx8mp: request irq after initializing dwc3 2021-08-26 13:10:56 +02:00
dwc3-keystone.c usb: dwc3: fix incorrect kernel-doc comment syntax in files 2021-04-02 15:20:51 +02:00
dwc3-meson-g12a.c usb: dwc3: meson-g12a: fix shared reset control use 2021-11-17 14:29:13 +01:00
dwc3-of-simple.c usb: dwc3: Add driver for Xilinx platforms 2021-03-23 12:48:14 +01:00
dwc3-omap.c usb: dwc3: omap: improve extcon initialization 2021-05-10 15:04:37 +02:00
dwc3-pci.c usb: dwc3: pci: Fix Bay Trail phy GPIO mappings 2022-02-17 16:10:03 +01:00
dwc3-qcom.c usb: dwc3: qcom: Fix NULL vs IS_ERR checking in dwc3_qcom_probe 2022-01-06 15:26:21 +01:00
dwc3-st.c usb: dwc3: st: fix incorrect kernel-doc comment syntax in file 2021-04-02 15:20:46 +02:00
dwc3-xilinx.c usb: dwc3: xilinx: fix uninitialized return value 2022-01-31 10:24:00 +01:00
ep0.c Merge v5.14-rc3 into usb-next 2021-07-26 11:16:46 +02:00
gadget.c usb: dwc3: gadget: Let the interrupt handler disable bottom halves. 2022-02-24 11:16:38 +01:00
gadget.h usb: dwc3: add cancelled reasons for dwc3 requests 2021-04-02 15:27:36 +02:00
host.c usb: dwc3: Drop unneeded calls to platform_get_resource_byname() 2021-12-21 08:51:57 +01:00
io.h usb: dwc3: fix incorrect kernel-doc comment syntax in files 2021-04-02 15:20:51 +02:00
Kconfig usb: exynos: describe driver in KConfig 2021-10-05 12:55:50 +02:00
Makefile usb: dwc3: Add driver for Xilinx platforms 2021-03-23 12:48:14 +01:00
trace.c usb: dwc3: fix incorrect kernel-doc comment syntax in files 2021-04-02 15:20:51 +02:00
trace.h usb: dwc3: trace: Remove unused fields in dwc3_log_trb 2021-05-27 09:30:01 +02:00
ulpi.c usb: dwc3: ulpi: Fix USB2.0 HS/FS/LS PHY suspend regression 2020-12-28 15:55:44 +01:00