On Wed, Sep 16, 2020 at 01:51:14AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 6b02addb Add linux-next specific files for 20200915 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=15888efd900000 > kernel config: https://syzkaller.appspot.com/x/.config?x=7086d0e9e44d4a14 > dashboard link: https://syzkaller.appspot.com/bug?extid=f4d0f0f7c860608404c4 > compiler: gcc (GCC) 10.1.0-syz 20200507 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+f4d0f0f7c86060840...@syzkaller.appspotmail.com > > ================================ > WARNING: inconsistent lock state > 5.9.0-rc5-next-20200915-syzkaller #0 Not tainted > -------------------------------- > inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-R} usage. > kworker/1:1/23 [HC0[0]:SC1[1]:HE0:SE0] takes: > ffff8880a6ff5f28 (&s->seqcount#12){+.+-}-{0:0}, at: > xfrm_policy_lookup_inexact_addr+0x57/0x200 net/xfrm/xfrm_policy.c:1909 > {SOFTIRQ-ON-W} state was registered at: > lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5398 > write_seqcount_t_begin_nested include/linux/seqlock.h:509 [inline] > write_seqcount_t_begin include/linux/seqlock.h:535 [inline] > write_seqlock include/linux/seqlock.h:883 [inline] > xfrm_set_spdinfo+0x302/0x660 net/xfrm/xfrm_user.c:1185
This is &net->xfrm.policy_hthresh.lock. ... > stack backtrace: > CPU: 1 PID: 23 Comm: kworker/1:1 Not tainted > 5.9.0-rc5-next-20200915-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Workqueue: wg-crypt-wg0 wg_packet_tx_worker > Call Trace: > <IRQ> > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x198/0x1fb lib/dump_stack.c:118 > print_usage_bug kernel/locking/lockdep.c:3694 [inline] > valid_state kernel/locking/lockdep.c:3705 [inline] > mark_lock_irq kernel/locking/lockdep.c:3908 [inline] > mark_lock.cold+0x13/0x10d kernel/locking/lockdep.c:4375 > mark_usage kernel/locking/lockdep.c:4252 [inline] > __lock_acquire+0x1402/0x55d0 kernel/locking/lockdep.c:4750 > lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5398 > seqcount_lockdep_reader_access+0x139/0x1a0 include/linux/seqlock.h:103 > xfrm_policy_lookup_inexact_addr+0x57/0x200 net/xfrm/xfrm_policy.c:1909 And this is a completely different seqlock. Again lockdep is creating a bogus report by lumping two unrelated locks (but of the same type, in this case seqlock) together. Cheers, -- Email: Herbert Xu <herb...@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
