forked from Minki/linux
ab219221a5
The dummy-hcd driver calls the gadget driver's disconnect callback under the wrong conditions. It should invoke the callback when Vbus power is turned off, but instead it does so when the D+ pullup is turned off. This can cause a deadlock in the composite core when a gadget driver is unregistered: [ 88.361471] ============================================ [ 88.362014] WARNING: possible recursive locking detected [ 88.362580] 4.14.0-rc2+ #9 Not tainted [ 88.363010] -------------------------------------------- [ 88.363561] v4l_id/526 is trying to acquire lock: [ 88.364062] (&(&cdev->lock)->rlock){....}, at: [<ffffffffa0547e03>] composite_disconnect+0x43/0x100 [libcomposite] [ 88.365051] [ 88.365051] but task is already holding lock: [ 88.365826] (&(&cdev->lock)->rlock){....}, at: [<ffffffffa0547b09>] usb_function_deactivate+0x29/0x80 [libcomposite] [ 88.366858] [ 88.366858] other info that might help us debug this: [ 88.368301] Possible unsafe locking scenario: [ 88.368301] [ 88.369304] CPU0 [ 88.369701] ---- [ 88.370101] lock(&(&cdev->lock)->rlock); [ 88.370623] lock(&(&cdev->lock)->rlock); [ 88.371145] [ 88.371145] *** DEADLOCK *** [ 88.371145] [ 88.372211] May be due to missing lock nesting notation [ 88.372211] [ 88.373191] 2 locks held by v4l_id/526: [ 88.373715] #0: (&(&cdev->lock)->rlock){....}, at: [<ffffffffa0547b09>] usb_function_deactivate+0x29/0x80 [libcomposite] [ 88.374814] #1: (&(&dum_hcd->dum->lock)->rlock){....}, at: [<ffffffffa05bd48d>] dummy_pullup+0x7d/0xf0 [dummy_hcd] [ 88.376289] [ 88.376289] stack backtrace: [ 88.377726] CPU: 0 PID: 526 Comm: v4l_id Not tainted 4.14.0-rc2+ #9 [ 88.378557] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 88.379504] Call Trace: [ 88.380019] dump_stack+0x86/0xc7 [ 88.380605] __lock_acquire+0x841/0x1120 [ 88.381252] lock_acquire+0xd5/0x1c0 [ 88.381865] ? composite_disconnect+0x43/0x100 [libcomposite] [ 88.382668] _raw_spin_lock_irqsave+0x40/0x54 [ 88.383357] ? composite_disconnect+0x43/0x100 [libcomposite] [ 88.384290] composite_disconnect+0x43/0x100 [libcomposite] [ 88.385490] set_link_state+0x2d4/0x3c0 [dummy_hcd] [ 88.386436] dummy_pullup+0xa7/0xf0 [dummy_hcd] [ 88.387195] usb_gadget_disconnect+0xd8/0x160 [udc_core] [ 88.387990] usb_gadget_deactivate+0xd3/0x160 [udc_core] [ 88.388793] usb_function_deactivate+0x64/0x80 [libcomposite] [ 88.389628] uvc_function_disconnect+0x1e/0x40 [usb_f_uvc] This patch changes the code to test the port-power status bit rather than the port-connect status bit when deciding whether to isue the callback. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: David Tulloh <david@tulloh.id.au> CC: <stable@vger.kernel.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> |
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| .. | ||
| bdc | ||
| amd5536udc_pci.c | ||
| amd5536udc.h | ||
| at91_udc.c | ||
| at91_udc.h | ||
| atmel_usba_udc.c | ||
| atmel_usba_udc.h | ||
| bcm63xx_udc.c | ||
| core.c | ||
| dummy_hcd.c | ||
| fotg210-udc.c | ||
| fotg210.h | ||
| fsl_mxc_udc.c | ||
| fsl_qe_udc.c | ||
| fsl_qe_udc.h | ||
| fsl_udc_core.c | ||
| fsl_usb2_udc.h | ||
| fusb300_udc.c | ||
| fusb300_udc.h | ||
| goku_udc.c | ||
| goku_udc.h | ||
| gr_udc.c | ||
| gr_udc.h | ||
| Kconfig | ||
| lpc32xx_udc.c | ||
| m66592-udc.c | ||
| m66592-udc.h | ||
| Makefile | ||
| mv_u3d_core.c | ||
| mv_u3d.h | ||
| mv_udc_core.c | ||
| mv_udc.h | ||
| net2272.c | ||
| net2272.h | ||
| net2280.c | ||
| net2280.h | ||
| omap_udc.c | ||
| omap_udc.h | ||
| pch_udc.c | ||
| pxa25x_udc.c | ||
| pxa25x_udc.h | ||
| pxa27x_udc.c | ||
| pxa27x_udc.h | ||
| r8a66597-udc.c | ||
| r8a66597-udc.h | ||
| renesas_usb3.c | ||
| s3c2410_udc.c | ||
| s3c2410_udc.h | ||
| s3c-hsudc.c | ||
| snps_udc_core.c | ||
| snps_udc_plat.c | ||
| trace.c | ||
| trace.h | ||
| udc-xilinx.c | ||