+Andrey mark_rodata_ro becomes extremely slow with KASAN. Frequently that causes the rcu stall message, but then kernel boots fine. It probably has something to do with large number of pgd? I had to disable CONFIG_DEBUG_RODATA with KASAN. On Mon, Oct 10, 2016 at 11:16 AM, 'Alexander Potapenko' via kasan-dev <kasan-dev@xxxxxxxxxxxxxxxx> wrote: > The stack trace looks unrelated to KASAN. > > On Sun, Oct 9, 2016 at 6:31 AM, kernel test robot > <fengguang.wu@xxxxxxxxx> wrote: >> Greetings, >> >> 0day kernel testing robot got the below dmesg and the first bad commit is >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master >> >> commit 80a9201a5965f4715d5c09790862e0df84ce0614 >> Author: Alexander Potapenko <glider@xxxxxxxxxx> >> AuthorDate: Thu Jul 28 15:49:07 2016 -0700 >> Commit: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> >> CommitDate: Thu Jul 28 16:07:41 2016 -0700 >> >> mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB >> >> For KASAN builds: >> - switch SLUB allocator to using stackdepot instead of storing the >> allocation/deallocation stacks in the objects; >> - change the freelist hook so that parts of the freelist can be put >> into the quarantine. >> >> [aryabinin@xxxxxxxxxxxxx: fixes] >> Link: http://lkml.kernel.org/r/1468601423-28676-1-git-send-email-aryabinin@xxxxxxxxxxxxx >> Link: http://lkml.kernel.org/r/1468347165-41906-3-git-send-email-glider@xxxxxxxxxx >> Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> >> Cc: Andrey Konovalov <adech.fo@xxxxxxxxx> >> Cc: Christoph Lameter <cl@xxxxxxxxx> >> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> >> Cc: Steven Rostedt (Red Hat) <rostedt@xxxxxxxxxxx> >> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> >> Cc: Kostya Serebryany <kcc@xxxxxxxxxx> >> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> >> Cc: Kuthonuzo Luruo <kuthonuzo.luruo@xxxxxxx> >> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> >> >> +----------------------------------------------------------------------------+------------+------------+------------+ >> | | c146a2b98e | 80a9201a59 | a61bc9c9af | >> +----------------------------------------------------------------------------+------------+------------+------------+ >> | boot_successes | 655 | 86 | 9 | >> | boot_failures | 0 | 139 | 16 | >> | INFO:rcu_sched_stall_on_CPU(#ticks_this_GP)idle=#(t=#jiffies_q=#) | 0 | 139 | 10 | >> | calltrace:mark_rodata_ro | 0 | 139 | 14 | >> | Kernel_panic-not_syncing:VFS:Unable_to_mount_root_fs_on_unknown-block(#,#) | 0 | 0 | 2 | >> | calltrace:prepare_namespace | 0 | 0 | 2 | >> | WARNING:at_arch/x86/mm/dump_pagetables.c:#note_page | 0 | 0 | 6 | >> +----------------------------------------------------------------------------+------------+------------+------------+ >> >> [ 14.024541] Write protecting the kernel read-only data: 18432k >> [ 14.030857] Freeing unused kernel memory: 1936K (ffff88000e81c000 - ffff88000ea00000) >> [ 14.043192] Freeing unused kernel memory: 248K (ffff88000efc2000 - ffff88000f000000) >> [ 114.005845] INFO: rcu_sched stall on CPU (84741 ticks this GP) idle=140000000000000 (t=100000 jiffies q=1) >> [ 114.009928] CPU: 0 PID: 1 Comm: swapper Not tainted 4.7.0-05999-g80a9201 #1 >> [ 114.011362] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 >> [ 114.013154] 0000000000000000 ffffffffacc40db8 ffffffffabfc7274 ffffffffacc40df8 >> [ 114.014763] ffffffffabae00ec 0000000000000001 0000000000000000 0000000000000000 >> [ 114.016378] 00000019dcf1a68b ffffffffacc40f18 fffffffface7e488 ffffffffacc40e18 >> [ 114.017988] Call Trace: >> [ 114.018504] <IRQ> [<ffffffffabfc7274>] dump_stack+0x19/0x1b >> [ 114.019739] [<ffffffffabae00ec>] check_cpu_stall+0xc0/0x124 >> [ 114.021041] [<ffffffffabae0283>] rcu_check_callbacks+0x50/0xa0 >> [ 114.022263] [<ffffffffabae62fe>] update_process_times+0x2e/0x52 >> [ 114.023503] [<ffffffffabaf8f5f>] tick_sched_handle+0x66/0x6d >> [ 114.024813] [<ffffffffabaf8fa3>] tick_sched_timer+0x3d/0x78 >> [ 114.025977] [<ffffffffabae733d>] __hrtimer_run_queues+0x252/0x45b >> [ 114.027461] [<ffffffffabaf8f66>] ? tick_sched_handle+0x6d/0x6d >> [ 114.028793] [<ffffffffabae70eb>] ? hrtimer_start_range_ns+0x315/0x315 >> [ 114.030130] [<ffffffffaba29b24>] ? kvm_clock_get_cycles+0x9/0xb >> [ 114.031367] [<ffffffffabaf1120>] ? ktime_get_update_offsets_now+0xf1/0x184 >> [ 114.032784] [<ffffffffabae76d4>] hrtimer_interrupt+0x8c/0x189 >> [ 114.033983] [<ffffffffaba1f190>] local_apic_timer_interrupt+0x42/0x44 >> [ 114.035337] [<ffffffffac417ba8>] smp_apic_timer_interrupt+0x55/0x66 >> [ 114.036636] [<ffffffffac416b6d>] apic_timer_interrupt+0x7d/0x90 >> [ 114.037864] <EOI> [<ffffffffaba37538>] ? note_page+0x2b/0x7af >> [ 114.039125] [<ffffffffaba375db>] ? note_page+0xce/0x7af >> [ 114.040219] [<ffffffffaba37fff>] ptdump_walk_pgd_level_core+0x343/0x483 >> [ 114.041583] [<ffffffffaba37cbc>] ? note_page+0x7af/0x7af >> [ 114.042577] [<ffffffffaba38168>] ptdump_walk_pgd_level_checkwx+0x17/0x2f >> [ 114.043639] [<ffffffffaba2dc93>] mark_rodata_ro+0x14b/0x152 >> [ 114.044545] [<ffffffffac40ce10>] kernel_init+0x29/0x100 >> [ 114.045393] [<ffffffffac4162df>] ret_from_fork+0x1f/0x40 >> [ 114.046252] [<ffffffffac40cde7>] ? rest_init+0xce/0xce >> [ 118.107577] x86/mm: Checked W+X mappings: passed, no W+X pages found. >> [ 118.113902] rcu-torture: rtc: ffffffffaddea720 ver: 1 tfle: 0 rta: 1 rtaf: 0 rtf: 0 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1 barrier: 0/0:0 cbflood: 1 >> >> git bisect start v4.8 v4.7 -- >> git bisect bad e6e7214fbbdab1f90254af68e0927bdb24708d22 # 07:46 9- 9 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip >> git bisect bad ba929b6646c5b87c7bb15cd8d3e51617725c983b # 08:00 14- 7 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs >> git bisect good 468fc7ed5537615efe671d94248446ac24679773 # 08:21 219+ 2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next >> git bisect bad e55884d2c6ac3ae50e49a1f6fe38601a91181719 # 08:34 17- 7 Merge tag 'vfio-v4.8-rc1' of git://github.com/awilliam/linux-vfio >> git bisect good 554828ee0db41618d101d9549db8808af9fd9d65 # 08:47 220+ 0 Merge branch 'salted-string-hash' >> git bisect good ce8c891c3496d3ea4a72ec40beac9a7b7f6649bf # 09:07 225+ 0 Merge tag 'rproc-v4.8' of git://github.com/andersson/remoteproc >> git bisect bad 1c88e19b0f6a8471ee50d5062721ba30b8fd4ba9 # 09:20 2- 3 Merge branch 'akpm' (patches from Andrew) >> git bisect good c9b011a87dd49bac1632311811c974bb7cd33c25 # 09:39 225+ 1 Merge tag 'hwlock-v4.8' of git://github.com/andersson/remoteproc >> git bisect good 6039b80eb50a893476fea7d56e86ed2d19290054 # 10:02 216+ 1 Merge tag 'dmaengine-4.8-rc1' of git://git.infradead.org/users/vkoul/slave-dma >> git bisect good bca6759258dbef378bcf5b872177bcd2259ceb68 # 10:20 224+ 0 mm, vmstat: remove zone and node double accounting by approximating retries >> git bisect good efdc94907977d2db84b4b00cb9bd98ca011f6819 # 10:33 225+ 0 mm: fix memcg stack accounting for sub-page stacks >> git bisect good fb399b4854d2159a4d23fbfbd7daaed914fd54fa # 10:46 225+ 1 mm/memblock.c: fix index adjustment error in __next_mem_range_rev() >> git bisect bad 31a6c1909f51dbe9bf08eb40dc64e3db90cf6f79 # 11:00 6- 6 mm, page_alloc: set alloc_flags only once in slowpath >> git bisect good c146a2b98eb5898eb0fab15a332257a4102ecae9 # 11:14 215+ 0 mm, kasan: account for object redzone in SLUB's nearest_obj() >> git bisect bad 87cc271d5e4320d705cfdf59f68d4d037b3511b2 # 11:24 14- 5 lib/stackdepot.c: use __GFP_NOWARN for stack allocations >> git bisect bad 80a9201a5965f4715d5c09790862e0df84ce0614 # 11:36 1- 1 mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB >> # first bad commit: [80a9201a5965f4715d5c09790862e0df84ce0614] mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB >> git bisect good c146a2b98eb5898eb0fab15a332257a4102ecae9 # 11:52 655+ 0 mm, kasan: account for object redzone in SLUB's nearest_obj() >> # extra tests with CONFIG_DEBUG_INFO_REDUCED >> git bisect bad 80a9201a5965f4715d5c09790862e0df84ce0614 # 12:11 8- 5 mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB >> # extra tests on HEAD of linux-devel/devel-spot-201610090613 >> git bisect bad a61bc9c9af01517642ddecff8d6f2425baf33e61 # 12:12 0- 16 0day head guard for 'devel-spot-201610090613' >> # extra tests on tree/branch linus/master >> git bisect bad b66484cd74706fa8681d051840fe4b18a3da40ff # 12:29 6- 2 Merge branch 'akpm' (patches from Andrew) >> # extra tests on tree/branch linus/master >> git bisect bad b66484cd74706fa8681d051840fe4b18a3da40ff # 12:30 0- 2 Merge branch 'akpm' (patches from Andrew) >> # extra tests on tree/branch linux-next/master >> git bisect bad c802e87fbe2d4dd58982d01b3c39bc5a781223aa # 12:31 0- 1 Add linux-next specific files for 20161006 >> >> >> --- >> 0-DAY kernel test infrastructure Open Source Technology Center >> https://lists.01.org/pipermail/lkp Intel Corporation > > > > -- > Alexander Potapenko > Software Engineer > > Google Germany GmbH > Erika-Mann-Straße, 33 > 80636 München > > Geschäftsführer: Matthew Scott Sucherman, Paul Terence Manicle > Registergericht und -nummer: Hamburg, HRB 86891 > Sitz der Gesellschaft: Hamburg > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. > To post to this group, send email to kasan-dev@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/CAG_fn%3DVgv3Mr%3DKftNyu21Zjpam8wN9TFvwy2KHLy9cKi_XsQfA%40mail.gmail.com. > For more options, visit https://groups.google.com/d/optout. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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