On Fri, Feb 20, 2009 at 05:45:04PM +0530, Shivdas Gujare wrote: > Hi all, > > Currently I am testing USB serial device with BeagleBoard(omap3) which > uses musb host controller. But I gets following Warnings every time > if I tries to open the /dev/ttyUSB0 using simple application which I > have written to open/read and write. > > FYI, I currently tested with 2.6.29-rc5 and also 2.6.29-rc2, with no success. > > What could be the possible reason? Is there any way, I can avoid this warning? > Thanks for your valuable help. > > Regards, > Shivdas > > > ------------[ cut here ]------------ > WARNING: at kernel/mutex.c:135 __mutex_lock_slowpath+0x6c/0x234() > Modules linked in: usbserial > [<c029d188>] (dump_stack+0x0/0x14) from [<c00516b4>] (warn_slowpath+0x68/0x9c) > [<c005164c>] (warn_slowpath+0x0/0x9c) from [<c029e0d0>] > (__mutex_lock_slowpath+0x6c/0x234) > r3:c039437c r2:00000000 > r7:c787e9c0 r6:c7bc6c00 r5:c7bc6fb4 r4:c7bc6c00 > [<c029e064>] (__mutex_lock_slowpath+0x0/0x234) from [<c029e2a8>] > (mutex_lock+0x10/0x14) > [<c029e298>] (mutex_lock+0x0/0x14) from [<c01a0d10>] > (echo_set_canon_col+0x1c/0x40) > [<c01a0cf4>] (echo_set_canon_col+0x0/0x40) from [<c01a2bcc>] > (n_tty_receive_buf+0xbdc/0x1074) > r5:00000000 r4:000000fe > [<c01a1ff0>] (n_tty_receive_buf+0x0/0x1074) from [<c01a513c>] > (flush_to_ldisc+0xf0/0x184) > [<c01a504c>] (flush_to_ldisc+0x0/0x184) from [<c01a520c>] > (tty_flip_buffer_push+0x3c/0x4c) > [<c01a51d0>] (tty_flip_buffer_push+0x0/0x4c) from [<bf0028b8>] > (usb_serial_generic_read_bulk_callback+0x12c/0x170 [usbserial]) > [<bf00278c>] (usb_serial_generic_read_bulk_callback+0x0/0x170 > [usbserial]) from [<c01e60b8>] (usb_hcd_giveback_urb+0xb0/0xfc) > r8:c78d88d8 r7:00000000 r6:c78d8800 r5:00000000 r4:c7851440 > [<c01e6008>] (usb_hcd_giveback_urb+0x0/0xfc) from [<c01f8148>] > (__musb_giveback+0xf4/0x110) Ick. Alan, echo_set_cannon_col is being called from tty_flip_buffer_push and trying to grab a mutex, yet we are in interrupt context as we are in a USB urb callback. Any thoughts? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
