Hi Marc, FYI here is another bisect result. The attached reproduce-* script can be used to reproduce the bug. https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core commit 336a9cde10d641e70bac67d90ae91b3190c3edca Author: Marc Zyngier AuthorDate: Fri Jan 15 17:41:09 2016 +0000 Commit: Thomas Gleixner CommitDate: Sat Feb 18 10:58:39 2017 +0100 hrtimer: Catch invalid clockids again commit 82e88ff1ea94 ("hrtimer: Revert CLOCK_MONOTONIC_RAW support") removed unfortunately a sanity check in the hrtimer code which was part of that MONOTONIC_RAW patch series. It would have caught the bogus usage of CLOCK_MONOTONIC_RAW in the wireless code. So bring it back. It is way too easy to take any random clockid and feed it to the hrtimer subsystem. At best, it gets mapped to a monotonic base, but it would be better to just catch illegal values as early as possible. Detect invalid clockids, map them to CLOCK_MONOTONIC and emit a warning. [ tglx: Replaced the BUG by a WARN and gracefully map to CLOCK_MONOTONIC ] Signed-off-by: Marc Zyngier Cc: Tomasz Nowicki Cc: Christoffer Dall Link: http://lkml.kernel.org/r/1452879670-16133-3-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner +------------------------------------------------+----+ | | | +------------------------------------------------+----+ | boot_successes | 0 | | boot_failures | 14 | | WARNING:at_kernel/time/hrtimer.c:#hrtimer_init | 14 | +------------------------------------------------+----+ [ 11.389488] usbcore: registered new interface driver rndis_wlan [ 11.390766] mac80211_hwsim: initializing netlink [ 11.392770] ieee80211 phy0: Selected rate control algorithm 'minstrel_ht' [ 11.395185] ieee80211 phy0: hwaddr 02:00:00:00:00:00 registered [ 11.396436] ------------[ cut here ]------------ [ 11.397434] WARNING: CPU: 1 PID: 1 at kernel/time/hrtimer.c:1090 hrtimer_init+0x11f/0x199 [ 11.399376] Invalid clockid 4. Using MONOTONIC [ 11.400394] Modules linked in: [ 11.401135] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.10.0-rc3-00262-g336a9cd #19 [ 11.402936] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 11.405253] Call Trace: [ 11.405978] dump_stack+0x82/0xb8 [ 11.406869] __warn+0xc2/0xdd [ 11.407697] warn_slowpath_fmt+0x4b/0x53 [ 11.408686] ? lock_is_held_type+0x4b/0x54 [ 11.409712] hrtimer_init+0x11f/0x199 [ 11.410666] ? mac80211_hwsim_get_tsf+0x1d/0x1d [ 11.411766] tasklet_hrtimer_init+0x1b/0x4f [ 11.412802] mac80211_hwsim_new_radio+0x7fe/0x916 [ 11.413935] ? set_debug_rodata+0x12/0x12 [ 11.414904] init_mac80211_hwsim+0x138/0x29f [ 11.415822] ? rndis_wlan_driver_init+0x1b/0x1b [ 11.416775] do_one_initcall+0x90/0x142 [ 11.417632] ? set_debug_rodata+0x12/0x12 [ 11.418511] kernel_init_freeable+0x1cb/0x258 [ 11.419433] ? rest_init+0x13b/0x13b [ 11.420233] kernel_init+0xe/0xf5 [ 11.421006] ret_from_fork+0x2a/0x40 [ 11.421838] ---[ end trace 9c23eceab0d16aa5 ]--- [ 11.423540] ieee80211 phy1: Selected rate control algorithm 'minstrel_ht' git bisect start 1bfab2a67acd98d304f10dd97ece67b49cdb7859 c470abd4fde40ea6a0846a2beab642a578c0b8cd -- git bisect bad 33e55ede40298f90716d997dec2d5cd3d18cc090 # 08:21 0- 4 Merge 'tip/master' into devel-catchup-201702200722 git bisect good 74278703a4b1dac67022baddc728cf17782a47ae # 08:37 20+ 0 0day base guard for 'devel-catchup-201702200722' git bisect good 6755d070e04210d4d9826697b6f64178a8ff41cf # 08:55 21+ 1 Merge branch 'sched/core' git bisect good 12372f63e2728a509817b56878cd6633d92053b3 # 09:09 22+ 0 Fix: sched/headers: Split out of git bisect good 4c1ede10727f3dc483a5d7a91042a1b9eb794b0f # 09:40 22+ 1 Merge branch 'WIP.sched/core' git bisect good 7410aa1ca377aa8c5ed340647b5228e7b5d0494a # 10:13 21+ 0 x86/boot/e820: Separate the E820 ABI structures from the in-kernel structures git bisect good 9062eadf11c25db273cb2f56c79f4b5415f6664f # 10:27 20+ 0 Merge branch 'WIP.x86/fpu' git bisect good a0b2f5af4c99d3da7ce9bc2b3b4641c8ffd22615 # 10:39 20+ 1 perf tools: Be consistent on the type of map->symbols[] interator git bisect good bfc3e353a4fda5d2feb36b87b388af9cd6bd359f # 11:19 20+ 1 Merge branch 'x86/mm' git bisect good 369a47d9283c7995d3a489064eeabddf3f6a08a0 # 12:02 20+ 0 Merge branch 'irq/core' git bisect bad 20d13e0244e50dc3f5b07beb3bc4fc0688eb2d46 # 12:02 0- 20 Merge branch 'timers/core' git bisect bad 336a9cde10d641e70bac67d90ae91b3190c3edca # 12:02 0- 14 hrtimer: Catch invalid clockids again # first bad commit: [336a9cde10d641e70bac67d90ae91b3190c3edca] hrtimer: Catch invalid clockids again git bisect good dba9a0babdd938a51d11ae81f9c40d07ca613f43 # 14:28 63+ 1 math64, tile: Fix build failure # extra tests with CONFIG_DEBUG_INFO_REDUCED git bisect bad 336a9cde10d641e70bac67d90ae91b3190c3edca # 14:28 0- 12 hrtimer: Catch invalid clockids again # extra tests on HEAD of linux-devel/devel-catchup-201702200722 git bisect bad 1bfab2a67acd98d304f10dd97ece67b49cdb7859 # 14:29 0- 35 0day head guard for 'devel-catchup-201702200722' # extra tests on tree/branch tip/timers/core git bisect bad 336a9cde10d641e70bac67d90ae91b3190c3edca # 14:32 0- 14 hrtimer: Catch invalid clockids again # extra tests with first bad commit reverted git bisect good 3bd6c9cda650730b700aceda08c76304a3fecb6a # 16:40 60+ 0 Revert "hrtimer: Catch invalid clockids again" # extra tests on tree/branch tip/master git bisect bad 20d13e0244e50dc3f5b07beb3bc4fc0688eb2d46 # 16:41 0- 20 Merge branch 'timers/core' --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation