From: Peter Chen peter.chen@nxp.com
[ Upstream commit 3c73bc52195def14165c3a7d91bdbb33b51725f5 ]
The threaded interrupt handler may still be called after the usb_gadget_disconnect is called, it causes the structures used at interrupt handler was freed before it uses, eg the usb_request. This issue usually occurs we remove the udc function during the transfer. Below is the example when doing stress test for android switch function, the EP0's request is freed by .unbind (configfs_composite_unbind -> composite_dev_cleanup), but the threaded handler accesses this request during handling setup packet request.
In fact, there is no protection between unbind the udc and udc interrupt handling, so we have to avoid the interrupt handler is occurred or scheduled during the .unbind flow.
init: Sending signal 9 to service 'adbd' (pid 18077) process group... android_work: did not send uevent (0 0 000000007bec2039) libprocessgroup: Successfully killed process cgroup uid 0 pid 18077 in 6ms init: Service 'adbd' (pid 18077) received signal 9 init: Sending signal 9 to service 'adbd' (pid 18077) process group... libprocessgroup: Successfully killed process cgroup uid 0 pid 18077 in 0ms init: processing action (init.svc.adbd=stopped) from (/init.usb.configfs.rc:14) init: Received control message 'start' for 'adbd' from pid: 399 (/vendor/bin/hw/android.hardware.usb@1.
init: starting service 'adbd'... read descriptors read strings Unable to handle kernel read from unreadable memory at virtual address 000000000000002a android_work: sent uevent USB_STATE=CONNECTED Mem abort info: ESR = 0x96000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000000e97f1000 using random self ethernet address [000000000000002a] pgd=0000000000000000 Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 232 Comm: irq/68-5b110000 Not tainted 5.4.24-06075-g94a6b52b5815 #92 Hardware name: Freescale i.MX8QXP MEK (DT) pstate: 00400085 (nzcv daIf +PAN -UAO) using random host ethernet address pc : composite_setup+0x5c/0x1730 lr : android_setup+0xc0/0x148 sp : ffff80001349bba0 x29: ffff80001349bba0 x28: ffff00083a50da00 x27: ffff8000124e6000 x26: ffff800010177950 x25: 0000000000000040 x24: ffff000834e18010 x23: 0000000000000000 x22: 0000000000000000 x21: ffff00083a50da00 x20: ffff00082e75ec40 x19: 0000000000000000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000001 x11: ffff80001180fb58 x10: 0000000000000040 x9 : ffff8000120fc980 x8 : 0000000000000000 x7 : ffff00083f98df50 x6 : 0000000000000100 x5 : 00000307e8978431 x4 : ffff800011386788 x3 : 0000000000000000 x2 : ffff800012342000 x1 : 0000000000000000 x0 : ffff800010c6d3a0 Call trace: composite_setup+0x5c/0x1730 android_setup+0xc0/0x148 cdns3_ep0_delegate_req+0x64/0x90 cdns3_check_ep0_interrupt_proceed+0x384/0x738 cdns3_device_thread_irq_handler+0x124/0x6e0 cdns3_thread_irq+0x94/0xa0 irq_thread_fn+0x30/0xa0 irq_thread+0x150/0x248 kthread+0xfc/0x128 ret_from_fork+0x10/0x18 Code: 910e8000 f9400693 12001ed7 79400f79 (3940aa61) ---[ end trace c685db37f8773fba ]--- Kernel panic - not syncing: Fatal exception SMP: stopping secondary CPUs Kernel Offset: disabled CPU features: 0x0002,20002008 Memory Limit: none Rebooting in 5 seconds..
Reviewed-by: Jun Li jun.li@nxp.com Signed-off-by: Peter Chen peter.chen@nxp.com Signed-off-by: Felipe Balbi balbi@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/gadget/udc/core.c | 2 ++ include/linux/usb/gadget.h | 2 ++ 2 files changed, 4 insertions(+)
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 9b11046480fe..2e28dde8376f 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1297,6 +1297,8 @@ static void usb_gadget_remove_driver(struct usb_udc *udc) kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
usb_gadget_disconnect(udc->gadget); + if (udc->gadget->irq) + synchronize_irq(udc->gadget->irq); udc->driver->unbind(udc->gadget); usb_gadget_udc_stop(udc);
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index 9411c08a5c7e..73a6113322c6 100644 --- a/include/linux/usb/gadget.h +++ b/include/linux/usb/gadget.h @@ -373,6 +373,7 @@ struct usb_gadget_ops { * @connected: True if gadget is connected. * @lpm_capable: If the gadget max_speed is FULL or HIGH, this flag * indicates that it supports LPM as per the LPM ECN & errata. + * @irq: the interrupt number for device controller. * * Gadgets have a mostly-portable "gadget driver" implementing device * functions, handling all usb configurations and interfaces. Gadget @@ -427,6 +428,7 @@ struct usb_gadget { unsigned deactivated:1; unsigned connected:1; unsigned lpm_capable:1; + int irq; }; #define work_to_gadget(w) (container_of((w), struct usb_gadget, work))