Hello, On Monday, June 22, 2009 2:34 PM, Peter Korsgaard wrote: > Marek> I would like to ask if someone has successfully used g_serial > Marek> USB gadget driver with kernel 2.6.29 or 2.6.30? I'm developing > Marek> a low level hardware driver for USB gadgets on ARM S3C6410 > Marek> platform. This driver is working quite fine (I've used it a > Marek> lot with g_ether CDC/RNDIS ethernet gadget driver). During my > Marek> development I've found the following bug in g_serial driver: > > You are aware that Ben Dooks has written an UDC driver for the OTG > controller on the s3c6410 which is now in mainline, right? > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux- > 2.6.git;a=commit;h=5b7d70c6dbf2db786395cbd21750a1a4ce222f84 Yes, I am aware. That driver does not work well for me (but this is the other case). However I did a test with his driver and the result was also a kernel oops: [ 162.520000] BUG: sleeping function called from invalid context at kernel/mutex.c:94 [ 162.530000] in_atomic(): 1, irqs_disabled(): 0, pid: 504, name: cat [ 162.540000] [<c0024afc>] (unwind_backtrace+0x0/0xdc) from [<c0268a28>] (mutex_lock+0x14/0x30) [ 162.540000] [<c0268a28>] (mutex_lock+0x14/0x30) from [<c014ceb4>] (echo_set_canon_col+0x1c/0x44) [ 162.550000] [<c014ceb4>] (echo_set_canon_col+0x1c/0x44) from [<c014eeb0>] (n_tty_receive_buf+0xbf0/0xec4) [ 162.560000] [<c014eeb0>] (n_tty_receive_buf+0xbf0/0xec4) from [<c015137c>] (flush_to_ldisc+0x104/0x1b0) [ 162.570000] [<c015137c>] (flush_to_ldisc+0x104/0x1b0) from [<bf002238>] (gs_rx_push+0x118/0x1cc [g_serial]) [ 162.580000] [<bf002238>] (gs_rx_push+0x118/0x1cc [g_serial]) from [<c003c780>] (tasklet_action+0x78/0xc8) [ 162.590000] [<c003c780>] (tasklet_action+0x78/0xc8) from [<c003cc14>] (__do_softirq+0x6c/0xf4) [ 162.600000] [<c003cc14>] (__do_softirq+0x6c/0xf4) from [<c003cce0>] (irq_exit+0x44/0x5c) [ 162.610000] [<c003cce0>] (irq_exit+0x44/0x5c) from [<c001e054>] (_text+0x54/0x6c) [ 162.610000] [<c001e054>] (_text+0x54/0x6c) from [<c001ea28>] (__irq_svc+0x48/0x9c) [ 162.620000] Exception stack(0xc6567e78 to 0xc6567ec0) [ 162.630000] 7e60: c6c883c0 00000013 [ 162.640000] 7e80: ffffffff 00000001 00000013 00000004 c64df800 00000013 c6566000 c659c0a0 [ 162.640000] 7ea0: c6526c30 c64df800 c6567e80 c6567ec0 c02699bc c02699d0 60000013 ffffffff [ 162.650000] [<c001ea28>] (__irq_svc+0x48/0x9c) from [<c02699bc>] (_spin_unlock_irqrestore+0xc/0x44) [ 162.660000] [<c02699bc>] (_spin_unlock_irqrestore+0xc/0x44) from [<bf000d24>] (gs_write+0x5c/0x68 [g_serial]) [ 162.670000] [<bf000d24>] (gs_write+0x5c/0x68 [g_serial]) from [<c014d870>] (n_tty_write+0x240/0x39c) [ 162.680000] [<c014d870>] (n_tty_write+0x240/0x39c) from [<c014b078>] (tty_write+0x180/0x21c) [ 162.690000] [<c014b078>] (tty_write+0x180/0x21c) from [<c008c4d4>] (vfs_write+0xac/0x158) [ 162.700000] [<c008c4d4>] (vfs_write+0xac/0x158) from [<c008c638>] (sys_write+0x40/0x6c) [ 162.700000] [<c008c638>] (sys_write+0x40/0x6c) from [<c001ede0>] (ret_fast_syscall+0x0/0x2c) [ 162.710000] ------------[ cut here ]------------ [ 162.720000] WARNING: at kernel/mutex.c:207 __mutex_lock_slowpath+0x6c/0x2c8() [ 162.720000] Modules linked in: g_serial [ 162.730000] [<c0024afc>] (unwind_backtrace+0x0/0xdc) from [<c0037e94>] (warn_slowpath_common+0x4c/0x80) [ 162.740000] [<c0037e94>] (warn_slowpath_common+0x4c/0x80) from [<c026808c>] (__mutex_lock_slowpath+0x6c/0x2c8) [ 162.750000] [<c026808c>] (__mutex_lock_slowpath+0x6c/0x2c8) from [<c0268a30>] (mutex_lock+0x1c/0x30) [ 162.760000] [<c0268a30>] (mutex_lock+0x1c/0x30) from [<c014ceb4>] (echo_set_canon_col+0x1c/0x44) [ 162.770000] [<c014ceb4>] (echo_set_canon_col+0x1c/0x44) from [<c014eeb0>] (n_tty_receive_buf+0xbf0/0xec4) [ 162.780000] [<c014eeb0>] (n_tty_receive_buf+0xbf0/0xec4) from [<c015137c>] (flush_to_ldisc+0x104/0x1b0) [ 162.780000] [<c015137c>] (flush_to_ldisc+0x104/0x1b0) from [<bf002238>] (gs_rx_push+0x118/0x1cc [g_serial]) [ 162.790000] [<bf002238>] (gs_rx_push+0x118/0x1cc [g_serial]) from [<c003c780>] (tasklet_action+0x78/0xc8) [ 162.800000] [<c003c780>] (tasklet_action+0x78/0xc8) from [<c003cc14>] (__do_softirq+0x6c/0xf4) [ 162.810000] [<c003cc14>] (__do_softirq+0x6c/0xf4) from [<c003cce0>] (irq_exit+0x44/0x5c) [ 162.820000] [<c003cce0>] (irq_exit+0x44/0x5c) from [<c001e054>] (_text+0x54/0x6c) [ 162.830000] [<c001e054>] (_text+0x54/0x6c) from [<c001ea28>] (__irq_svc+0x48/0x9c) [ 162.840000] Exception stack(0xc6567e78 to 0xc6567ec0) [ 162.840000] 7e60: c6c883c0 00000013 [ 162.850000] 7e80: ffffffff 00000001 00000013 00000004 c64df800 00000013 c6566000 c659c0a0 [ 162.860000] 7ea0: c6526c30 c64df800 c6567e80 c6567ec0 c02699bc c02699d0 60000013 ffffffff [ 162.870000] [<c001ea28>] (__irq_svc+0x48/0x9c) from [<c02699bc>] (_spin_unlock_irqrestore+0xc/0x44) [ 162.870000] [<c02699bc>] (_spin_unlock_irqrestore+0xc/0x44) from [<bf000d24>] (gs_write+0x5c/0x68 [g_serial]) [ 162.880000] [<bf000d24>] (gs_write+0x5c/0x68 [g_serial]) from [<c014d870>] (n_tty_write+0x240/0x39c) [ 162.890000] [<c014d870>] (n_tty_write+0x240/0x39c) from [<c014b078>] (tty_write+0x180/0x21c) [ 162.900000] [<c014b078>] (tty_write+0x180/0x21c) from [<c008c4d4>] (vfs_write+0xac/0x158) [ 162.910000] [<c008c4d4>] (vfs_write+0xac/0x158) from [<c008c638>] (sys_write+0x40/0x6c) [ 162.920000] [<c008c638>] (sys_write+0x40/0x6c) from [<c001ede0>] (ret_fast_syscall+0x0/0x2c) [ 162.930000] ---[ end trace aa3ca3a4bfa49b54 ]--- [ 162.930000] BUG: scheduling while atomic: cat/504/0x00000104 [ 162.940000] Modules linked in: g_serial [ 162.940000] [ 162.940000] Pid: 504, comm: cat [ 162.950000] CPU: 0 Tainted: G W (2.6.30 #334) [ 162.950000] PC is at _spin_unlock_irqrestore+0x20/0x44 [ 162.960000] LR is at _spin_unlock_irqrestore+0xc/0x44 [ 162.960000] pc : [<c02699d0>] lr : [<c02699bc>] psr: 60000013 [ 162.960000] sp : c6567ec0 ip : c6567e80 fp : c64df800 [ 162.970000] r10: c6526c30 r9 : c659c0a0 r8 : c6566000 [ 162.980000] r7 : 00000013 r6 : c64df800 r5 : 00000004 r4 : 00000013 [ 162.990000] r3 : 00000001 r2 : ffffffff r1 : 00000013 r0 : c6c883c0 [ 162.990000] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 163.000000] Control: 00c5387d Table: 565d0008 DAC: 00000015 When I disabled Preemptive kernel and disabled debugs in Kernel Hacking section I only got the following message: [ 69.810000] BUG: scheduling while atomic: cat/499/0x00000100 [ 69.820000] Modules linked in: g_serial [ 69.820000] [ 69.820000] Pid: 499, comm: cat [ 69.830000] CPU: 0 Not tainted (2.6.30 #336) [ 69.830000] PC is at gs_write+0x50/0x58 [g_serial] [ 69.840000] LR is at check_preempt_wakeup+0x24/0x114 [ 69.840000] pc : [<bf000a48>] lr : [<c002fc5c>] psr: 60000013 [ 69.840000] sp : c6553ed0 ip : c64698e0 fp : c6469c00 [ 69.850000] r10: c6469b80 r9 : c6ffd300 r8 : c6552000 [ 69.860000] r7 : 00000005 r6 : 00000004 r5 : 00000013 r4 : c6ffd980 [ 69.860000] r3 : 00000004 r2 : 00000000 r1 : 00000001 r0 : 00000000 [ 69.870000] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 69.880000] Control: 00c5387d Table: 56580008 DAC: 00000015 > I've used the g_serial driver on 2.6.29 without problems (not on > s3c6410 though). On what hardware you use the g_serial driver? It is ARM-based? I understand that this might be also related to the way that low level hardware gadget driver is implemented, but I really have no idea how to hunt for this bug. Best regards -- Marek Szyprowski Samsung Poland R&D Center -- 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
