Re: [serial] 13a7238eea: WARNING: CPU: 0 PID: 1 at drivers/tty/serial/serial_core.c:99 uart_change_pm+0x35/0x162

Peter Hurley
2016-05-04T03:34:06Z

Hi,

On 05/03/2016 08:13 PM, kernel test robot wrote:
>
> FYI, we noticed the following commit:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
> commit 13a7238eeab5718bf968e2a835205ba659a38a77 ("serial: core: Prevent unsafe uart port access, part 3")

This should be fixed on most recent tty-testing and tty-next branches.

Please re-test on last tty-testing branch including commit 7da4b8b7378790dd1e4af1bb7522863127fa1438
("serial: core: Fix port mutex assert if lockdep disabled")

Regards,
Peter Hurley

> on test machine: vm-vp-quantal-x86_64: 2 threads qemu-system-x86_64 -enable-kvm with 360M memory
>
> caused below changes:
>
>
> [ 7.249323] ------------[ cut here ]------------
> [ 7.249323] ------------[ cut here ]------------
> [ 7.250172] WARNING: CPU: 0 PID: 1 at drivers/tty/serial/serial_core.c:99 uart_change_pm+0x35/0x162
> [ 7.250172] WARNING: CPU: 0 PID: 1 at drivers/tty/serial/serial_core.c:99 uart_change_pm+0x35/0x162
> [ 7.252110] Modules linked in:
> [ 7.252110] Modules linked in:
>
> [ 7.252679] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G B 4.6.0-rc5-00015-g13a7238 #1
> [ 7.252679] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G B 4.6.0-rc5-00015-g13a7238 #1
> [ 7.254232] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
> [ 7.254232] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
> [ 7.255806] 0000000000000000
> [ 7.255806] 0000000000000000 ffff88000f42f668 ffff88000f42f668 ffffffff815a2566 ffffffff815a2566 0000000000000286 0000000000000286
>
> [ 7.257180] 0000000041b58ab3
> [ 7.257180] 0000000041b58ab3 ffffffff81f66067 ffffffff81f66067 ffffffff815a240c ffffffff815a240c ffffffff81f7647d ffffffff81f7647d
>
> [ 7.258601] ffffffff81238abf
> [ 7.258601] ffffffff81238abf 000000000042f6a8 000000000042f6a8 ffffed0001e85ecb ffffed0001e85ecb 0000000000000000 0000000000000000
>
> [ 7.259973] Call Trace:
> [ 7.259973] Call Trace:
> [ 7.260422] [<ffffffff815a2566>] dump_stack+0x15a/0x1de
> [ 7.260422] [<ffffffff815a2566>] dump_stack+0x15a/0x1de
> [ 7.261374] [<ffffffff815a240c>] ? _atomic_dec_and_lock+0xaf/0xaf
> [ 7.261374] [<ffffffff815a240c>] ? _atomic_dec_and_lock+0xaf/0xaf
> [ 7.262470] [<ffffffff81238abf>] ? is_module_text_address+0x1f/0x1f
> [ 7.262470] [<ffffffff81238abf>] ? is_module_text_address+0x1f/0x1f
> [ 7.263595] [<ffffffff817af33b>] ? uart_change_pm+0x35/0x162
> [ 7.263595] [<ffffffff817af33b>] ? uart_change_pm+0x35/0x162
> [ 7.264623] [<ffffffff8110d1fc>] __warn+0x16e/0x189
> [ 7.264623] [<ffffffff8110d1fc>] __warn+0x16e/0x189
> [ 7.265523] [<ffffffff8110d37a>] warn_slowpath_null+0x18/0x1a
> [ 7.265523] [<ffffffff8110d37a>] warn_slowpath_null+0x18/0x1a
> [ 7.266561] [<ffffffff817af33b>] uart_change_pm+0x35/0x162
> [ 7.266561] [<ffffffff817af33b>] uart_change_pm+0x35/0x162
> [ 7.267553] [<ffffffff817b6ba1>] uart_add_one_port+0xb36/0x1008
> [ 7.267553] [<ffffffff817b6ba1>] uart_add_one_port+0xb36/0x1008
> [ 7.268637] [<ffffffff817b606b>] ? uart_unregister_driver+0x150/0x150
> [ 7.268637] [<ffffffff817b606b>] ? uart_unregister_driver+0x150/0x150
> [ 7.269786] [<ffffffff81b45c0e>] ? mutex_trylock+0x4eb/0x4eb
> [ 7.269786] [<ffffffff81b45c0e>] ? mutex_trylock+0x4eb/0x4eb
> [ 7.270838] [<ffffffff817bcba7>] serial8250_register_8250_port+0xf68/0x14e5
> [ 7.270838] [<ffffffff817bcba7>] serial8250_register_8250_port+0xf68/0x14e5
> [ 7.272116] [<ffffffff817bed3f>] serial_pnp_probe+0x2d8/0x5f1
> [ 7.272116] [<ffffffff817bed3f>] serial_pnp_probe+0x2d8/0x5f1
> [ 7.273146] [<ffffffff817bea67>] ? check_name+0x6e/0x6e
> [ 7.273146] [<ffffffff817bea67>] ? check_name+0x6e/0x6e
> [ 7.274125] [<ffffffff817bea67>] ? check_name+0x6e/0x6e
> [ 7.274125] [<ffffffff817bea67>] ? check_name+0x6e/0x6e
> [ 7.275076] [<ffffffff817625ff>] pnp_device_probe+0x1c1/0x1dc
> [ 7.275076] [<ffffffff817625ff>] pnp_device_probe+0x1c1/0x1dc
> [ 7.276109] [<ffffffff817f3514>] driver_probe_device+0x325/0x63c
> [ 7.276109] [<ffffffff817f3514>] driver_probe_device+0x325/0x63c
> [ 7.277191] [<ffffffff817f382b>] ? driver_probe_device+0x63c/0x63c
> [ 7.277191] [<ffffffff817f382b>] ? driver_probe_device+0x63c/0x63c
> [ 7.278299] [<ffffffff817f3963>] __driver_attach+0x138/0x179
> [ 7.278299] [<ffffffff817f3963>] __driver_attach+0x138/0x179
> [ 7.279316] [<ffffffff817eee66>] bus_for_each_dev+0x10d/0x143
> [ 7.279316] [<ffffffff817eee66>] bus_for_each_dev+0x10d/0x143
> [ 7.280372] [<ffffffff817eed59>] ? next_device+0x52/0x52
> [ 7.280372] [<ffffffff817eed59>] ? next_device+0x52/0x52
> [ 7.281334] [<ffffffff817f27c5>] driver_attach+0x50/0x53
> [ 7.281334] [<ffffffff817f27c5>] driver_attach+0x50/0x53
> [ 7.282302] [<ffffffff817f1cb3>] bus_add_driver+0x31d/0x53e
> [ 7.282302] [<ffffffff817f1cb3>] bus_add_driver+0x31d/0x53e
> [ 7.283346] [<ffffffff817f5063>] driver_register+0x24b/0x2c3
> [ 7.283346] [<ffffffff817f5063>] driver_register+0x24b/0x2c3
> [ 7.284370] [<ffffffff81761ce6>] pnp_register_driver+0x98/0x9f
> [ 7.284370] [<ffffffff81761ce6>] pnp_register_driver+0x98/0x9f
> [ 7.285420] [<ffffffff834431e7>] ? univ8250_console_init+0x28/0x28
> [ 7.285420] [<ffffffff834431e7>] ? univ8250_console_init+0x28/0x28
> [ 7.286579] [<ffffffff817bf068>] serial8250_pnp_init+0x10/0x12
> [ 7.286579] [<ffffffff817bf068>] serial8250_pnp_init+0x10/0x12
> [ 7.287635] [<ffffffff83443259>] serial8250_init+0x72/0x232
> [ 7.287635] [<ffffffff83443259>] serial8250_init+0x72/0x232
> [ 7.288650] [<ffffffff834431e7>] ? univ8250_console_init+0x28/0x28
> [ 7.288650] [<ffffffff834431e7>] ? univ8250_console_init+0x28/0x28
> [ 7.289775] [<ffffffff81000598>] do_one_initcall+0x287/0x36d
> [ 7.289775] [<ffffffff81000598>] do_one_initcall+0x287/0x36d
> [ 7.290802] [<ffffffff81000311>] ? try_to_run_init_process+0x31/0x31
> [ 7.290802] [<ffffffff81000311>] ? try_to_run_init_process+0x31/0x31
> [ 7.291954] [<ffffffff833d900a>] kernel_init_freeable+0x60e/0x6a9
> [ 7.291954] [<ffffffff833d900a>] kernel_init_freeable+0x60e/0x6a9
> [ 7.293060] [<ffffffff81b3e0fd>] kernel_init+0xc/0x11b
> [ 7.293060] [<ffffffff81b3e0fd>] kernel_init+0xc/0x11b
> [ 7.293998] [<ffffffff81b4f6a2>] ret_from_fork+0x22/0x40
> [ 7.293998] [<ffffffff81b4f6a2>] ret_from_fork+0x22/0x40
> [ 7.294964] [<ffffffff81b3e0f1>] ? rest_init+0xe8/0xe8
> [ 7.294964] [<ffffffff81b3e0f1>] ? rest_init+0xe8/0xe8
> [ 7.295921] ---[ end trace 3dfe53a1b1117774 ]---
> [ 7.295921] ---[ end trace 3dfe53a1b1117774 ]---
>
>
> FYI, raw QEMU command line is:
>
> qemu-system-x86_64 -enable-kvm -kernel /pkg/linux/x86_64-randconfig-s0-04291414/gcc-5/13a7238eeab5718bf968e2a835205ba659a38a77/vmlinuz-4.6.0-rc5-00015-g13a7238 -append 'root=/dev/ram0 user=lkp job=/lkp/scheduled/vm-vp-quantal-x86_64-44/bisect_boot-1-quantal-core-x86_64.cgz-x86_64-randconfig-s0-04291414-13a7238eeab5718bf968e2a835205ba659a38a77-20160429-40248-hp2gqc-0.yaml ARCH=x86_64 kconfig=x86_64-randconfig-s0-04291414 branch=linux-devel/devel-spot-201604291342 commit=13a7238eeab5718bf968e2a835205ba659a38a77 BOOT_IMAGE=/pkg/linux/x86_64-randconfig-s0-04291414/gcc-5/13a7238eeab5718bf968e2a835205ba659a38a77/vmlinuz-4.6.0-rc5-00015-g13a7238 max_uptime=600 RESULT_ROOT=/result/boot/1/vm-vp-quantal-x86_64/quantal-core-x86_64.cgz/x86_64-randconfig-s0-04291414/gcc-5/13a7238eeab5718bf968e2a835205ba659a38a77/0 LKP_SERVER=inn earlyprintk=ttyS0,115200 systemd.log_level=err debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic o
ops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal rw ip=::::vm-vp-quantal-x86_64-44::dhcp drbd.minor_count=8' -initrd /fs/sdi1/initrd-vm-vp-quantal-x86_64-44 -m 360 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -pidfile /dev/shm/kboot/pid-vm-vp-quantal-x86_64-44 -serial file:/dev/shm/kboot/serial-vm-vp-quantal-x86_64-44 -daemonize -display none -monitor null
>
>
>
>
>
> Thanks,
> Xiaolong
>