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* Re: possible deadlock in __synchronize_srcu
       [not found] <001a114a6b20cafb9c055cd73f86@google.com>
@ 2017-10-31 13:20 ` Dmitry Vyukov
  2017-10-31 14:54   ` Vlastimil Babka
  0 siblings, 1 reply; 3+ messages in thread
From: Dmitry Vyukov @ 2017-10-31 13:20 UTC (permalink / raw)
  To: syzbot
  Cc: Andrew Morton, Christoph Lameter, Joonsoo Kim, LKML, linux-mm,
	Pekka Enberg, David Rientjes, syzkaller-bugs, kasan-dev

On Tue, Oct 31, 2017 at 3:54 PM, syzbot
<bot+b8ff4d5c3fa77f2e2f0f9be34e6b2795ffc3c65e@syzkaller.appspotmail.com>
wrote:
> Hello,
>
> syzkaller hit the following crash on
> 9506597de2cde02d48c11d5c250250b9143f59f7
> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master
> compiler: gcc (GCC) 7.1.1 20170620
> .config is attached
> Raw console output is attached.

Another reincarnation of:
https://groups.google.com/d/msg/syzkaller-bugs/PCeHYAmw-TQ/TKMoo6xhAgAJ

#syz dup: possible deadlock in process_one_work



> ======================================================
> WARNING: possible circular locking dependency detected
> 4.13.0-rc6-next-20170824+ #8 Not tainted
> ------------------------------------------------------
> kworker/u4:2/57 is trying to acquire lock:
>  ((complete)&rcu.completion){+.+.}, at: [<ffffffff815afff5>]
> __synchronize_srcu+0x1b5/0x250 kernel/rcu/srcutree.c:898
>
> but task is already holding lock:
>  (slab_mutex){+.+.}, at: [<ffffffff8192b730>] kmem_cache_destroy+0x30/0x250
> mm/slab_common.c:821
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #3 (slab_mutex){+.+.}:
>        check_prevs_add kernel/locking/lockdep.c:2020 [inline]
>        validate_chain kernel/locking/lockdep.c:2469 [inline]
>        __lock_acquire+0x3286/0x4620 kernel/locking/lockdep.c:3498
>        lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002
>        __mutex_lock_common kernel/locking/mutex.c:756 [inline]
>        __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893
>        mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
>        kmem_cache_create+0x39/0x2a0 mm/slab_common.c:435
>        ptlock_cache_init+0x24/0x2d mm/memory.c:4632
>        pgtable_init include/linux/mm.h:1756 [inline]
>        mm_init init/main.c:504 [inline]
>        start_kernel+0x3d4/0x7ad init/main.c:569
>        x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:381
>        x86_64_start_kernel+0x13c/0x149 arch/x86/kernel/head64.c:362
>        verify_cpu+0x0/0xfb
>
> -> #2 (memcg_cache_ids_sem){.+.+}:
>        check_prevs_add kernel/locking/lockdep.c:2020 [inline]
>        validate_chain kernel/locking/lockdep.c:2469 [inline]
>        __lock_acquire+0x3286/0x4620 kernel/locking/lockdep.c:3498
>        lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002
>        down_read+0x96/0x150 kernel/locking/rwsem.c:23
>        memcg_get_cache_ids+0x10/0x20 mm/memcontrol.c:274
>        list_lru_destroy+0x96/0x490 mm/list_lru.c:573
>        deactivate_locked_super+0x94/0xd0 fs/super.c:315
>        deactivate_super+0x141/0x1b0 fs/super.c:339
>        cleanup_mnt+0xb2/0x150 fs/namespace.c:1113
>        mntput_no_expire+0x6e0/0xa90 fs/namespace.c:1179
>        mntput fs/namespace.c:1189 [inline]
>        kern_unmount+0x9c/0xd0 fs/namespace.c:2934
>        pid_ns_release_proc+0x37/0x50 fs/proc/root.c:231
>        proc_cleanup_work+0x19/0x20 kernel/pid_namespace.c:79
>        process_one_work+0xbfd/0x1be0 kernel/workqueue.c:2098
>        worker_thread+0x223/0x1860 kernel/workqueue.c:2233
>        kthread+0x39c/0x470 kernel/kthread.c:231
>        ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
>
> -> #1 ((&ns->proc_work)){+.+.}:
>        process_one_work+0xba5/0x1be0 kernel/workqueue.c:2095
>        worker_thread+0x223/0x1860 kernel/workqueue.c:2233
>        kthread+0x39c/0x470 kernel/kthread.c:231
>        ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
>        0xffffffffffffffff
>
> -> #0 ((complete)&rcu.completion){+.+.}:
>        check_prev_add+0x865/0x1520 kernel/locking/lockdep.c:1894
>        check_prevs_add kernel/locking/lockdep.c:2020 [inline]
>        validate_chain kernel/locking/lockdep.c:2469 [inline]
>        __lock_acquire+0x3286/0x4620 kernel/locking/lockdep.c:3498
>        lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002
>        complete_acquire include/linux/completion.h:39 [inline]
>        __wait_for_common kernel/sched/completion.c:108 [inline]
>        wait_for_common kernel/sched/completion.c:122 [inline]
>        wait_for_completion+0xc8/0x770 kernel/sched/completion.c:143
>        __synchronize_srcu+0x1b5/0x250 kernel/rcu/srcutree.c:898
>        synchronize_srcu_expedited kernel/rcu/srcutree.c:923 [inline]
>        synchronize_srcu+0x1a3/0x560 kernel/rcu/srcutree.c:974
>        quarantine_remove_cache+0xd7/0xf0 mm/kasan/quarantine.c:327
>        kasan_cache_shutdown+0x9/0x10 mm/kasan/kasan.c:381
>        shutdown_cache+0x15/0x1b0 mm/slab_common.c:531
>        kmem_cache_destroy+0x236/0x250 mm/slab_common.c:829
>        tipc_server_stop+0x13f/0x190 net/tipc/server.c:636
>        tipc_topsrv_stop+0x1fe/0x350 net/tipc/subscr.c:390
>        tipc_exit_net+0x15/0x40 net/tipc/core.c:96
>        ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142
>        cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:483
>        process_one_work+0xbfd/0x1be0 kernel/workqueue.c:2098
>        worker_thread+0x223/0x1860 kernel/workqueue.c:2233
>        kthread+0x39c/0x470 kernel/kthread.c:231
>        ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
>
> other info that might help us debug this:
>
> Chain exists of:
>   (complete)&rcu.completion --> memcg_cache_ids_sem --> slab_mutex
>
>  Possible unsafe locking scenario:
>
>        CPU0                    CPU1
>        ----                    ----
>   lock(slab_mutex);
>                                lock(memcg_cache_ids_sem);
>                                lock(slab_mutex);
>   lock((complete)&rcu.completion);
>
>  *** DEADLOCK ***
>
> 5 locks held by kworker/u4:2/57:
>  #0:  ("%s""netns"){.+.+}, at: [<ffffffff81464534>] __write_once_size
> include/linux/compiler.h:305 [inline]
>  #0:  ("%s""netns"){.+.+}, at: [<ffffffff81464534>] atomic64_set
> arch/x86/include/asm/atomic64_64.h:33 [inline]
>  #0:  ("%s""netns"){.+.+}, at: [<ffffffff81464534>] atomic_long_set
> include/asm-generic/atomic-long.h:56 [inline]
>  #0:  ("%s""netns"){.+.+}, at: [<ffffffff81464534>] set_work_data
> kernel/workqueue.c:617 [inline]
>  #0:  ("%s""netns"){.+.+}, at: [<ffffffff81464534>]
> set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
>  #0:  ("%s""netns"){.+.+}, at: [<ffffffff81464534>]
> process_one_work+0xad4/0x1be0 kernel/workqueue.c:2090
>  #1:  (net_cleanup_work){+.+.}, at: [<ffffffff8146458c>]
> process_one_work+0xb2c/0x1be0 kernel/workqueue.c:2094
>  #2:  (net_mutex){+.+.}, at: [<ffffffff83e50bc7>] cleanup_net+0x247/0xb60
> net/core/net_namespace.c:449
>  #3:  (cpu_hotplug_lock.rw_sem){++++}, at: [<ffffffff8192b722>]
> get_online_cpus include/linux/cpu.h:126 [inline]
>  #3:  (cpu_hotplug_lock.rw_sem){++++}, at: [<ffffffff8192b722>]
> kmem_cache_destroy+0x22/0x250 mm/slab_common.c:818
>  #4:  (slab_mutex){+.+.}, at: [<ffffffff8192b730>]
> kmem_cache_destroy+0x30/0x250 mm/slab_common.c:821
>
> stack backtrace:
> CPU: 1 PID: 57 Comm: kworker/u4:2 Not tainted 4.13.0-rc6-next-20170824+ #8
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Workqueue: netns cleanup_net
> Call Trace:
>  __dump_stack lib/dump_stack.c:16 [inline]
>  dump_stack+0x194/0x257 lib/dump_stack.c:52
>  print_circular_bug+0x503/0x710 kernel/locking/lockdep.c:1259
>  check_prev_add+0x865/0x1520 kernel/locking/lockdep.c:1894
>  check_prevs_add kernel/locking/lockdep.c:2020 [inline]
>  validate_chain kernel/locking/lockdep.c:2469 [inline]
>  __lock_acquire+0x3286/0x4620 kernel/locking/lockdep.c:3498
>  lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002
>  complete_acquire include/linux/completion.h:39 [inline]
>  __wait_for_common kernel/sched/completion.c:108 [inline]
>  wait_for_common kernel/sched/completion.c:122 [inline]
>  wait_for_completion+0xc8/0x770 kernel/sched/completion.c:143
>  __synchronize_srcu+0x1b5/0x250 kernel/rcu/srcutree.c:898
>  synchronize_srcu_expedited kernel/rcu/srcutree.c:923 [inline]
>  synchronize_srcu+0x1a3/0x560 kernel/rcu/srcutree.c:974
>  quarantine_remove_cache+0xd7/0xf0 mm/kasan/quarantine.c:327
>  kasan_cache_shutdown+0x9/0x10 mm/kasan/kasan.c:381
>  shutdown_cache+0x15/0x1b0 mm/slab_common.c:531
>  kmem_cache_destroy+0x236/0x250 mm/slab_common.c:829
>  tipc_server_stop+0x13f/0x190 net/tipc/server.c:636
>  tipc_topsrv_stop+0x1fe/0x350 net/tipc/subscr.c:390
>  tipc_exit_net+0x15/0x40 net/tipc/core.c:96
>  ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142
>  cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:483
>  process_one_work+0xbfd/0x1be0 kernel/workqueue.c:2098
>  worker_thread+0x223/0x1860 kernel/workqueue.c:2233
>  kthread+0x39c/0x470 kernel/kthread.c:231
>  ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
> QAT: Invalid ioctl
> QAT: Invalid ioctl
> QAT: Invalid ioctl
> QAT: Invalid ioctl
> TCP: request_sock_TCP: Possible SYN flooding on port 20012. Sending cookies.
> Check SNMP counters.
> sctp: [Deprecated]: syz-executor6 (pid 4597) Use of int in max_burst socket
> option deprecated.
> Use struct sctp_assoc_value instead
> audit: type=1326 audit(1503608734.272:8): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=4680 comm="syz-executor3"
> exe="/root/syz-executor3" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> audit: type=1326 audit(1503608734.367:9): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=4680 comm="syz-executor3"
> exe="/root/syz-executor3" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> sctp: [Deprecated]: syz-executor3 (pid 4928) Use of int in max_burst socket
> option.
> Use struct sctp_assoc_value instead
> sctp: [Deprecated]: syz-executor3 (pid 4928) Use of int in max_burst socket
> option.
> Use struct sctp_assoc_value instead
> TCP: request_sock_TCP: Possible SYN flooding on port 20020. Sending cookies.
> Check SNMP counters.
> mmap: syz-executor7 (5066): VmData 1892352 exceed data ulimit 1. Update
> limits or use boot option ignore_rlimit_data.
> nla_parse: 7 callbacks suppressed
> netlink: 5 bytes leftover after parsing attributes in process
> `syz-executor7'.
> IPv6: NLM_F_REPLACE set, but no existing node found!
> netlink: 5 bytes leftover after parsing attributes in process
> `syz-executor7'.
> ptm ptm1: ldisc open failed (-12), clearing slot 1
> IPv6: NLM_F_REPLACE set, but no existing node found!
> netlink: 3 bytes leftover after parsing attributes in process
> `syz-executor6'.
> netlink: 3 bytes leftover after parsing attributes in process
> `syz-executor6'.
> netlink: 3 bytes leftover after parsing attributes in process
> `syz-executor6'.
> device lo entered promiscuous mode
> netlink: 3 bytes leftover after parsing attributes in process
> `syz-executor6'.
> netlink: 3 bytes leftover after parsing attributes in process
> `syz-executor6'.
> netlink: 3 bytes leftover after parsing attributes in process
> `syz-executor6'.
> device lo entered promiscuous mode
> dccp_invalid_packet: invalid packet type
> dccp_invalid_packet: invalid packet type
> SELinux: unrecognized netlink message: protocol=0 nlmsg_type=65535
> sclass=netlink_route_socket pig=5222 comm=syz-executor3
> SELinux: unrecognized netlink message: protocol=0 nlmsg_type=65535
> sclass=netlink_route_socket pig=5222 comm=syz-executor3
> pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns
> pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns
> netlink: 8 bytes leftover after parsing attributes in process
> `syz-executor5'.
> netlink: 5 bytes leftover after parsing attributes in process
> `syz-executor5'.
> SELinux: unrecognized netlink message: protocol=6 nlmsg_type=3131
> sclass=netlink_xfrm_socket pig=5545 comm=syz-executor4
> SELinux: unrecognized netlink message: protocol=6 nlmsg_type=3131
> sclass=netlink_xfrm_socket pig=5545 comm=syz-executor4
> sctp: [Deprecated]: syz-executor3 (pid 5561) Use of struct sctp_assoc_value
> in delayed_ack socket option.
> Use struct sctp_sack_info instead
> sctp: [Deprecated]: syz-executor3 (pid 5561) Use of struct sctp_assoc_value
> in delayed_ack socket option.
> Use struct sctp_sack_info instead
> audit: type=1326 audit(1503608738.163:10): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=5622 comm="syz-executor5"
> exe="/root/syz-executor5" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> capability: warning: `syz-executor0' uses deprecated v2 capabilities in a
> way that may be insecure
> audit: type=1326 audit(1503608738.292:11): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=5622 comm="syz-executor5"
> exe="/root/syz-executor5" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> SELinux: unrecognized netlink message: protocol=0 nlmsg_type=1025
> sclass=netlink_route_socket pig=5659 comm=syz-executor1
> SELinux: unrecognized netlink message: protocol=0 nlmsg_type=1025
> sclass=netlink_route_socket pig=5684 comm=syz-executor1
> Assertion failed! net/irda/ircomm/ircomm_core.c:ircomm_flow_request:475 self
> != NULL
> QAT: Invalid ioctl
> QAT: Invalid ioctl
> audit: type=1326 audit(1503608739.537:12): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=5936 comm="syz-executor5"
> exe="/root/syz-executor5" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> SELinux: unrecognized netlink message: protocol=0 nlmsg_type=65535
> sclass=netlink_route_socket pig=5979 comm=syz-executor4
> tc_ctl_action: received NO action attribs
> SELinux: unrecognized netlink message: protocol=0 nlmsg_type=65535
> sclass=netlink_route_socket pig=5979 comm=syz-executor4
> sock: sock_set_timeout: `syz-executor2' (pid 5997) tries to set negative
> timeout
> sock: sock_set_timeout: `syz-executor2' (pid 5997) tries to set negative
> timeout
> tc_ctl_action: received NO action attribs
> sctp: [Deprecated]: syz-executor1 (pid 6154) Use of int in max_burst socket
> option deprecated.
> Use struct sctp_assoc_value instead
> sctp: [Deprecated]: syz-executor1 (pid 6156) Use of int in max_burst socket
> option deprecated.
> Use struct sctp_assoc_value instead
> QAT: Invalid ioctl
> SELinux:  unknown mount option
> SELinux:  unknown mount option
> QAT: Invalid ioctl
> audit: type=1326 audit(1503608741.554:13): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=6438 comm="syz-executor2"
> exe="/root/syz-executor2" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> audit: type=1326 audit(1503608741.579:14): auid=4294967295 uid=0 gid=0
> ses=4294967295 subj=kernel pid=6438 comm="syz-executor2"
> exe="/root/syz-executor2" sig=31 arch=c000003e syscall=202 compat=0
> ip=0x4512e9 code=0xffff0000
> PF_BRIDGE: RTM_NEWNEIGH with unknown ifindex
> *** Guest State ***
> CR0: actual=0x0000000080000031, shadow=0x0000000060000011,
> gh_mask=fffffffffffffff7
> CR4: actual=0x0000000000006154, shadow=0x0000000000004164,
> gh_mask=fffffffffffff871
> CR3 = 0x00000000fffbc000
> RSP = 0x0000000000000f80  RIP = 0x0000000000000000
> RFLAGS=0x00000002         DR7 = 0x0000000000000400
> Sysenter RSP=0000000000000f80 CS:RIP=0050:0000000000002810
> CS:   sel=0x0000, attr=0x0409b, limit=0x000fffff, base=0x0000000000000000
> DS:   sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000
> SS:   sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000
> ES:   sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000
> FS:   sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000
> GS:   sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000
> GDTR:                           limit=0x000007ff, base=0x0000000000001000
> LDTR: sel=0x0008, attr=0x04082, limit=0x000007ff, base=0x0000000000001800
> IDTR:                           limit=0x000001ff, base=0x0000000000003800
> TR:   sel=0x0000, attr=0x0008b, limit=0x0000ffff, base=0x0000000000000000
> EFER =     0x0000000000000001  PAT = 0x0007040600070406
> DebugCtl = 0x0000000000000000  DebugExceptions = 0x0000000000000000
> Interruptibility = 00000000  ActivityState = 00000000
> *** Host State ***
> RIP = 0xffffffff811b6277  RSP = 0xffff8801c8a074c8
> CS=0010 SS=0018 DS=0000 ES=0000 FS=0000 GS=0000 TR=0040
> FSBase=00007f51db980700 GSBase=ffff8801db200000 TRBase=ffff8801db223100
> GDTBase=ffffffffff577000 IDTBase=ffffffffff57b000
> CR0=0000000080050033 CR3=00000001cf27f000 CR4=00000000001426f0
> Sysenter RSP=0000000000000000 CS:RIP=0010:ffffffff84d9d0a0
> EFER = 0x0000000000000d01  PAT = 0x0000000000000000
> *** Control State ***
> PinBased=0000003f CPUBased=b699edfa SecondaryExec=0000004a
> EntryControls=0000d1ff ExitControls=0023efff
> ExceptionBitmap=00060042 PFECmask=00000000 PFECmatch=00000000
> VMEntry: intr_info=00000000 errcode=00000000 ilen=00000000
> VMExit: intr_info=00000000 errcode=00000000 ilen=00000000
>         reason=80000021 qualification=0000000000000000
> IDTVectoring: info=00000000 errcode=00000000
> TSC Offset = 0xffffffd760e51039
> EPT pointer = 0x00000001d8af001e
> PF_BRIDGE: RTM_NEWNEIGH with unknown ifindex
> nla_parse: 28 callbacks suppressed
> netlink: 5 bytes leftover after parsing attributes in process
> `syz-executor2'.
> netlink: 5 bytes leftover after parsing attributes in process
> `syz-executor2'.
>
>
> ---
> This bug is generated by a dumb bot. It may contain errors.
> See https://goo.gl/tpsmEJ for details.
> Direct all questions to syzkaller@googlegroups.com.
> Please credit me with: Reported-by: syzbot <syzkaller@googlegroups.com>
>
> syzbot will keep track of this bug report.
> Once a fix for this bug is committed, please reply to this email with:
> #syz fix: exact-commit-title
> To mark this as a duplicate of another syzbot report, please reply with:
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> If it's a one-off invalid bug report, please reply with:
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> Note: if the crash happens again, it will cause creation of a new bug
> report.
> Note: all commands must start from beginning of the line.
>
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^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: possible deadlock in __synchronize_srcu
  2017-10-31 13:20 ` possible deadlock in __synchronize_srcu Dmitry Vyukov
@ 2017-10-31 14:54   ` Vlastimil Babka
  2017-11-01 16:16     ` Dmitry Vyukov
  0 siblings, 1 reply; 3+ messages in thread
From: Vlastimil Babka @ 2017-10-31 14:54 UTC (permalink / raw)
  To: Dmitry Vyukov, syzbot
  Cc: Andrew Morton, Christoph Lameter, Joonsoo Kim, LKML, linux-mm,
	Pekka Enberg, David Rientjes, syzkaller-bugs, kasan-dev

On 10/31/2017 02:20 PM, Dmitry Vyukov wrote:
> On Tue, Oct 31, 2017 at 3:54 PM, syzbot
> <bot+b8ff4d5c3fa77f2e2f0f9be34e6b2795ffc3c65e@syzkaller.appspotmail.com>
> wrote:
>> Hello,
>>
>> syzkaller hit the following crash on
>> 9506597de2cde02d48c11d5c250250b9143f59f7

That's next-20170824. Why test/report such old next trees now?

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: possible deadlock in __synchronize_srcu
  2017-10-31 14:54   ` Vlastimil Babka
@ 2017-11-01 16:16     ` Dmitry Vyukov
  0 siblings, 0 replies; 3+ messages in thread
From: Dmitry Vyukov @ 2017-11-01 16:16 UTC (permalink / raw)
  To: Vlastimil Babka
  Cc: syzbot, Andrew Morton, Christoph Lameter, Joonsoo Kim, LKML,
	linux-mm, Pekka Enberg, David Rientjes, syzkaller-bugs,
	kasan-dev

On Tue, Oct 31, 2017 at 5:54 PM, Vlastimil Babka <vbabka@suse.cz> wrote:
> On 10/31/2017 02:20 PM, Dmitry Vyukov wrote:
>> On Tue, Oct 31, 2017 at 3:54 PM, syzbot
>> <bot+b8ff4d5c3fa77f2e2f0f9be34e6b2795ffc3c65e@syzkaller.appspotmail.com>
>> wrote:
>>> Hello,
>>>
>>> syzkaller hit the following crash on
>>> 9506597de2cde02d48c11d5c250250b9143f59f7
>
> That's next-20170824. Why test/report such old next trees now?


That's just a side effect of the fact that we started testing and
collecting crashes before we had all infrastructure to pipe bugs to
kernel mailing lists. So we ended up with a bug jam and now trying to
drain it. Some of the old bugs indeed ended up being fixed meanwhile.
But we reported the ones that are still relevant. Once we drain the
jam, we will start reporting fresh bugs. We are always testing the
latest revisions.

^ permalink raw reply	[flat|nested] 3+ messages in thread

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2017-10-31 13:20 ` possible deadlock in __synchronize_srcu Dmitry Vyukov
2017-10-31 14:54   ` Vlastimil Babka
2017-11-01 16:16     ` Dmitry Vyukov

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