On Tue, Jun 09, 2020 at 06:48:13PM -0700, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 5b14671b Merge tag 'fuse-update-5.8' of git://git.kernel.o.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=12a11ec1100000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d1ea633f7958e008 > dashboard link: https://syzkaller.appspot.com/bug?extid=0113b9be6667b5b50840 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+0113b9be6667b5b50840@xxxxxxxxxxxxxxxxxxxxxxxxx > > BUG: using smp_processor_id() in preemptible [00000000] code: systemd-rfkill/6740 > caller is ext4_mb_new_blocks+0xa77/0x3b30 fs/ext4/mballoc.c:4711 > CPU: 0 PID: 6740 Comm: systemd-rfkill Not tainted 5.7.0-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x18f/0x20d lib/dump_stack.c:118 > check_preemption_disabled lib/smp_processor_id.c:47 [inline] > debug_smp_processor_id.cold+0x88/0x9b lib/smp_processor_id.c:57 > ext4_mb_new_blocks+0xa77/0x3b30 fs/ext4/mballoc.c:4711 > ext4_ext_map_blocks+0x2044/0x3410 fs/ext4/extents.c:4244 > ext4_map_blocks+0x4cb/0x1640 fs/ext4/inode.c:626 > ext4_getblk+0xad/0x520 fs/ext4/inode.c:833 > ext4_bread+0x7c/0x380 fs/ext4/inode.c:883 > ext4_append+0x153/0x360 fs/ext4/namei.c:67 > ext4_init_new_dir fs/ext4/namei.c:2757 [inline] > ext4_mkdir+0x5e0/0xdf0 fs/ext4/namei.c:2802 > vfs_mkdir+0x419/0x690 fs/namei.c:3641 > do_mkdirat+0x21e/0x280 fs/namei.c:3664 > do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 > entry_SYSCALL_64_after_hwframe+0x49/0xb3 > RIP: 0033:0x7f449ff49687 > Code: Bad RIP value. > RSP: 002b:00007ffdd3b9fe58 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 > RAX: ffffffffffffffda RBX: 00005567752fd985 RCX: 00007f449ff49687 > RDX: 00007ffdd3b9fd20 RSI: 00000000000001ed RDI: 00005567752fd985 > RBP: 00007f449ff49680 R08: 0000000000000100 R09: 0000000000000000 > R10: 00005567752fd980 R11: 0000000000000246 R12: 00000000000001ed > R13: 00007ffdd3b9ffe0 R14: 0000000000000000 R15: 0000000000000000 I am seeing this all over the place on Linus's tree right now: [ +0.008563] BUG: using smp_processor_id() in preemptible [00000000] code: systemd/1 [ +0.000011] caller is ext4_mb_new_blocks+0x2ac/0xc10 [ +0.000002] CPU: 31 PID: 1 Comm: systemd Not tainted 5.7.0-14371-g25ae6195a4c7 #66 [ +0.000002] Hardware name: Micro-Star International Co., Ltd. MS-7C59/Creator TRX40 (MS-7C59), BIOS 1.50 05/13/2020 [ +0.000001] Call Trace: [ +0.000008] dump_stack+0x57/0x70 [ +0.000004] debug_smp_processor_id.cold+0x4e/0x53 [ +0.000001] ext4_mb_new_blocks+0x2ac/0xc10 [ +0.000004] ? ext4_find_extent+0x3e8/0x450 [ +0.000002] ext4_ext_map_blocks+0x9f6/0x1b10 [ +0.000003] ? ext4_mark_iloc_dirty+0x60f/0xa50 [ +0.000003] ? __ext4_journal_get_write_access+0x2d/0x70 [ +0.000004] ext4_map_blocks+0x119/0x5a0 [ +0.000004] ext4_getblk+0x66/0x1c0 [ +0.000003] ext4_bread+0x26/0xc0 [ +0.000002] ext4_append+0x49/0xe0 [ +0.000002] ext4_mkdir+0x233/0x450 [ +0.000005] vfs_mkdir+0x11d/0x1b0 [ +0.000003] do_mkdirat+0x92/0x130 [ +0.000004] do_syscall_64+0x43/0x80 [ +0.000004] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ +0.000003] RIP: 0033:0x7fef3df7a72b [ +0.000001] Code: Bad RIP value. [ +0.000001] RSP: 002b:00007ffdb4eba0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 [ +0.000003] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fef3df7a72b [ +0.000001] RDX: 0000000000000000 RSI: 00000000000001c0 RDI: 0000563b11cf26e0 [ +0.000001] RBP: 0000563b11cf2731 R08: 000000000000000d R09: 0000000000000002 [ +0.000000] R10: 11175e4331068ed5 R11: 0000000000000246 R12: 0000563b11cf26e0 [ +0.000002] R13: 00007fef3e019c20 R14: 00007ffdb4eba0f0 R15: 8421084210842109 Just a constant stream of them. There's a few other fun: [ +0.453222] BUG: unable to handle page fault for address: ffffb59cc2719000 [ +0.000004] #PF: supervisor write access in kernel mode [ +0.000001] #PF: error_code(0x000b) - reserved bit violation messages at times, but I don't think that's an ext4 issue, but rather something in the sound stack... EXT4 developers, any hints/patches to try? thanks, greg k-h
