I'm moving our systems to the recent kernel and have encountered an older musb issue [1] that occurs with some 3G/4G modems. In this case it is SIMCom 7600G-H. After this dump occurs the modem is still working though. [ 45.585644] ------------[ cut here ]------------ [ 45.590785] WARNING: CPU: 0 PID: 242 at drivers/usb/musb/musb_host.c:115 musb_h_tx_flush_fifo+0x118/0x138 [ 45.600421] musb-hdrc musb-hdrc.0: Could not flush host TX2 fifo: csr: 2403 [ 45.607433] Modules linked in: 8021q garp stp mrp llc wl18xx wlcore mac80211 libarc4 sha256_generic cfg80211 wlcore_sdio c_can_platform omap_rng rng_core c_can can_dev at24 gpio_pca953x omap_wdt watchdog rtc_omap leds_gpio led_class [ 45.628258] CPU: 0 PID: 242 Comm: ModemManager Not tainted 5.3.0-rc5 #2 [ 45.634920] Hardware name: Generic AM33XX (Flattened Device Tree) [ 45.641092] [<c0111d28>] (unwind_backtrace) from [<c010d000>] (show_stack+0x10/0x14) [ 45.648910] [<c010d000>] (show_stack) from [<c09bd0f0>] (dump_stack+0xd8/0x110) [ 45.656291] [<c09bd0f0>] (dump_stack) from [<c013a034>] (__warn+0xe0/0x10c) [ 45.663314] [<c013a034>] (__warn) from [<c013a0a4>] (warn_slowpath_fmt+0x44/0x6c) [ 45.670862] [<c013a0a4>] (warn_slowpath_fmt) from [<c076fbf0>] (musb_h_tx_flush_fifo+0x118/0x138) [ 45.679806] [<c076fbf0>] (musb_h_tx_flush_fifo) from [<c0770ef4>] (musb_cleanup_urb+0x128/0x204) [ 45.688660] [<c0770ef4>] (musb_cleanup_urb) from [<c077167c>] (musb_urb_dequeue+0x14c/0x234) [ 45.697165] [<c077167c>] (musb_urb_dequeue) from [<c07323fc>] (usb_hcd_unlink_urb+0x68/0x84) [ 45.705667] [<c07323fc>] (usb_hcd_unlink_urb) from [<c0768530>] (usb_wwan_write+0x64/0x1f0) [ 45.714090] [<c0768530>] (usb_wwan_write) from [<c075b600>] (serial_write+0x34/0x60) [ 45.721898] [<c075b600>] (serial_write) from [<c060e3ec>] (n_tty_write+0x360/0x460) [ 45.729626] [<c060e3ec>] (n_tty_write) from [<c060a1bc>] (tty_write+0x1c0/0x36c) [ 45.737092] [<c060a1bc>] (tty_write) from [<c02f0410>] (__vfs_write+0x28/0x1c4) [ 45.744465] [<c02f0410>] (__vfs_write) from [<c02f2f48>] (vfs_write+0xa0/0x184) [ 45.751835] [<c02f2f48>] (vfs_write) from [<c02f31e8>] (ksys_write+0x98/0xdc) [ 45.759033] [<c02f31e8>] (ksys_write) from [<c0101000>] (ret_fast_syscall+0x0/0x28) [ 45.766743] Exception stack(0xcb911fa8 to 0xcb911ff0) [ 45.771845] 1fa0: 00160170 bea0fc14 00000009 00141be9 00000001 bea0fc14 [ 45.780086] 1fc0: 00160170 bea0fc14 00000000 00000004 00141be9 00000001 00000001 00141be9 [ 45.788322] 1fe0: 00000000 bea0fbc8 b68d992b b68d9934 [ 45.793416] irq event stamp: 109442 [ 45.796945] hardirqs last enabled at (109441): [<c0101a74>] __irq_svc+0x74/0x98 [ 45.804406] hardirqs last disabled at (109442): [<c09dd3e8>] _raw_spin_lock_irqsave+0x1c/0x4c [ 45.812992] softirqs last enabled at (109180): [<c0102580>] __do_softirq+0x360/0x524 [ 45.820880] softirqs last disabled at (109157): [<c0141c28>] irq_exit+0x12c/0x17c [ 45.828416] ---[ end trace eecf6f3aa6209643 ]--- [1] https://patchwork.kernel.org/patch/7389591/ Regards, Yegor
