Hi, Paul: the enclosed is the log trigger the 120s hung_task_panic without other debug patches, the hung task is blocked at __wait_rcu_gp, it means the rcu_cpu_stall can't detect the scenario: echo 1 > /proc/sys/kernel/panic_on_rcu_stall echo 7 > /sys/module/rcupdate/parameters/rcu_cpu_stall_timeout
-----Original Message----- From: Paul E. McKenney <[email protected]> Sent: Monday, December 3, 2018 9:57 PM To: He, Bo <[email protected]> Cc: Steven Rostedt <[email protected]>; [email protected]; [email protected]; [email protected]; [email protected]; Zhang, Jun <[email protected]>; Xiao, Jin <[email protected]>; Zhang, Yanmin <[email protected]> Subject: Re: rcu_preempt caused oom On Mon, Dec 03, 2018 at 07:44:03AM +0000, He, Bo wrote: > Thanks, we have run the test for the whole weekend and not reproduce the > issue, so we confirm the CONFIG_RCU_BOOST can fix the issue. Very good, that is encouraging. Perhaps I should think about making CONFIG_RCU_BOOST=y the default for CONFIG_PREEMPT in mainline, at least for architectures for which rt_mutexes are implemented. > We have enabled the rcupdate.rcu_cpu_stall_timeout=7 and also set panic on > rcu stall and will see if we can see the panic, will keep you posed with the > test results. > echo 1 > /proc/sys/kernel/panic_on_rcu_stall Looking forward to seeing what is going on! Of course, to reproduce, you will need to again build with CONFIG_RCU_BOOST=n. Thanx, Paul > -----Original Message----- > From: Paul E. McKenney <[email protected]> > Sent: Saturday, December 1, 2018 12:49 AM > To: He, Bo <[email protected]> > Cc: Steven Rostedt <[email protected]>; > [email protected]; [email protected]; > [email protected]; [email protected]; Zhang, Jun > <[email protected]>; Xiao, Jin <[email protected]>; Zhang, Yanmin > <[email protected]> > Subject: Re: rcu_preempt caused oom > > On Fri, Nov 30, 2018 at 03:18:58PM +0000, He, Bo wrote: > > Here is the kernel cmdline: > > Thank you! > > > Kernel command line: androidboot.acpio_idx=0 > > androidboot.bootloader=efiwrapper-02_03-userdebug_kernelflinger-06_0 > > 3- userdebug androidboot.diskbus=00.0 > > androidboot.verifiedbootstate=green > > androidboot.bootreason=power-on androidboot.serialno=R1J56L6006a7bb > > g_ffs.iSerialNumber=R1J56L6006a7bb no_timer_check noxsaves > > reboot_panic=p,w i915.hpd_sense_invert=0x7 mem=2G nokaslr nopti > > ftrace_dump_on_oops trace_buf_size=1024K intel_iommu=off gpt > > loglevel=4 androidboot.hardware=gordon_peak > > firmware_class.path=/vendor/firmware relative_sleep_states=1 > > enforcing=0 androidboot.selinux=permissive cpu_init_udelay=10 > > androidboot.android_dt_dir=/sys/bus/platform/devices/ANDR0001:00/pro > > pe rties/android/ pstore.backend=ramoops memmap=0x1400000$0x50000000 > > ramoops.mem_address=0x50000000 ramoops.mem_size=0x1400000 > > ramoops.record_size=0x4000 ramoops.console_size=0x1000000 > > ramoops.ftrace_size=0x10000 ramoops.dump_oops=1 vga=current > > i915.modeset=1 drm.atomic=1 i915.nuclear_pageflip=1 > > drm.vblankoffdelay= > > And no sign of any suppression of RCU CPU stall warnings. Hmmm... > It does take more than 21 seconds to OOM? Or do things happen faster than > that? If they do happen faster than that, then on approach would be to add > something like this to the kernel command line: > > rcupdate.rcu_cpu_stall_timeout=7 > > This would set the stall timeout to seven seconds. Note that timeouts less > than three seconds are silently interpreted as three seconds. > > Thanx, Paul > > > -----Original Message----- > > From: Steven Rostedt <[email protected]> > > Sent: Friday, November 30, 2018 11:17 PM > > To: Paul E. McKenney <[email protected]> > > Cc: He, Bo <[email protected]>; [email protected]; > > [email protected]; [email protected]; > > [email protected]; Zhang, Jun <[email protected]>; Xiao, Jin > > <[email protected]>; Zhang, Yanmin <[email protected]> > > Subject: Re: rcu_preempt caused oom > > > > On Fri, 30 Nov 2018 06:43:17 -0800 > > "Paul E. McKenney" <[email protected]> wrote: > > > > > Could you please send me your list of kernel boot parameters? > > > They usually appear near the start of your console output. > > > > Or just: cat /proc/cmdline > > > > -- Steve > > >
apanic_console
Description: apanic_console
