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 >