Hi All, I think backtrace info get messed up due to email configuration. Let me post again. root@(none):~# INFO: rcu_sched detected stalls on CPUs/tasks: 6: (39 GPs behind) idle=83d/1/0 softirq=0/0 fqs=5228 (detected by 4, t=5254 jiffies, g=8752, c=8751, q=75869) Task dump for CPU 6: swapper/6 R running task 0 0 1 0x00000804 Call Trace: [c0000001f01379f0] [c000000000005e18] .do_IRQ+0x84/0x118 (unreliable) [c0000001f0137a80] [c00000000001793c] exc_0x500_common+0xfc/0x100 - interrupt: 501 at .book3e_idle+0x24/0x4c LR = .book3e_idle+0x24/0x4c [c0000001f0137d70] [c0000000000094a8] .arch_cpu_idle+0x34/0xa0 (unreliable) [c0000001f0137de0] [c000000000086bd0] .cpu_startup_entry+0x204/0x2ac [c0000001f0137ee0] [c00000000001edf8] .start_secondary+0x2b0/0x2d4 [c0000001f0137f90] [c00000000000046c] start_secondary_prolog+0x10/0x14 This is also seen sometimes: INFO: task udhcpc:3285 blocked for more than 120 seconds. Tainted: G O 4.1.8-rt8+gbd51baffc04e #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. udhcpc D 00003fff87215f78 0 3285 3245 0x00000000 Call Trace: [c0000001c42ef710] [c000000000008878] .__switch_to+0x8c/0xc4 [c0000001c42ef790] [c0000000009604cc] .__schedule+0x230/0x53c [c0000001c42ef840] [c00000000096081c] .schedule+0x44/0xe4 [c0000001c42ef8c0] [c000000000963de4] .schedule_timeout+0x194/0x210 [c0000001c42ef9a0] [c0000000009616c4] .wait_for_common+0x170/0x1d0 [c0000001c42efa60] [c00000000009d4ec] .wait_rcu_gp+0x5c/0x74 [c0000001c42efb10] [c00000000009ee7c] .synchronize_sched+0x4c/0x70 [c0000001c42efb80] [c0000000007df974] .synchronize_net+0x20/0x4c [c0000001c42efbf0] [c000000000906874] .__unregister_prot_hook+0x124/0x1c8 [c0000001c42efc80] [c000000000907014] .packet_do_bind+0x184/0x1e4 [c0000001c42efd10] [c0000000007c2d8c] .SyS_bind+0xf4/0x110 [c0000001c42efe30] [c000000000000698] system_call+0x38/0xc4 Thanks Shivam -----Original Message----- From: GARG Shivam Sent: Wednesday, September 23, 2020 12:07 PM To: Linux-usb@xxxxxxxxxxxxxxx Cc: Peter Chen <hzpeterchen@xxxxxxxxx>; Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> Subject: RE: Linux Crash with Gadget serial driver Hi All, I agree it is an old kernel but still can you look into the backtrace and guide me how I can proceed to stop the host crash. Below is the backtrace info that is coming as soon as I connect my gadget serial driver supported device(USB) to FreeBSD. Backtrace #1 root@(none):~# INFO: rcu_sched detected stalls on CPUs/tasks: 6: (39 GPs behind) idle=83d/1/0 softirq=0/0 fqs=5228 (detected by 4, t=5254 jiffies, g=8752, c=8751, q=75869) Task dump for CPU 6: swapper/6 R running task 0 0 1 0x00000804 Call Trace: [c0000001f01379f0] [c000000000005e18] .do_IRQ+0x84/0x118 (unreliable) [c0000001f0137a80] [c00000000001793c] exc_0x500_common+0xfc/0x100 - interrupt: 501 at .book3e_idle+0x24/0x4c LR = .book3e_idle+0x24/0x4c [c0000001f0137d70] [c0000000000094a8] .arch_cpu_idle+0x34/0xa0 (unreliable) [c0000001f0137de0] [c000000000086bd0] .cpu_startup_entry+0x204/0x2ac [c0000001f0137ee0] [c00000000001edf8] .start_secondary+0x2b0/0x2d4 [c0000001f0137f90] [c00000000000046c] start_secondary_prolog+0x10/0x14 This is also seen sometimes: INFO: task udhcpc:3285 blocked for more than 120 seconds. Tainted: G O 4.1.8-rt8+gbd51baffc04e #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. udhcpc D 00003fff87215f78 0 3285 3245 0x00000000 Call Trace: [c0000001c42ef710] [c000000000008878] .__switch_to+0x8c/0xc4 [c0000001c42ef790] [c0000000009604cc] .__schedule+0x230/0x53c [c0000001c42ef840] [c00000000096081c] .schedule+0x44/0xe4 [c0000001c42ef8c0] [c000000000963de4] .schedule_timeout+0x194/0x210 [c0000001c42ef9a0] [c0000000009616c4] .wait_for_common+0x170/0x1d0 [c0000001c42efa60] [c00000000009d4ec] .wait_rcu_gp+0x5c/0x74 [c0000001c42efb10] [c00000000009ee7c] .synchronize_sched+0x4c/0x70 [c0000001c42efb80] [c0000000007df974] .synchronize_net+0x20/0x4c [c0000001c42efbf0] [c000000000906874] .__unregister_prot_hook+0x124/0x1c8 [c0000001c42efc80] [c000000000907014] .packet_do_bind+0x184/0x1e4 [c0000001c42efd10] [c0000000007c2d8c] .SyS_bind+0xf4/0x110 [c0000001c42efe30] [c000000000000698] system_call+0x38/0xc4 Thanks Shivam -----Original Message----- From: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> Sent: Wednesday, August 26, 2020 3:06 PM To: GARG Shivam <shivam.garg@xxxxxxxxxxxxxxx> Cc: Peter Chen <hzpeterchen@xxxxxxxxx>; Linux-usb@xxxxxxxxxxxxxxx Subject: Re: Linux Crash with Gadget serial driver On Wed, Aug 26, 2020 at 09:09:32AM +0000, GARG Shivam wrote: > I am with Kernel version 4.1. 4.1 is over 6 years old and over 500 thousand changes and fixes behind what we are all working with now. Please work with your vendor who is forcing you to remain on an obsolete kernel version like this, as you are paying them for that type of support, there is nothing that we can do here with this, sorry. good luck! greg k-h