On Fri, Jan 29, 2021 at 09:35:46AM +0100, Dmitry Vyukov wrote: > On Fri, Jan 29, 2021 at 9:34 AM syzbot > <syzbot+51bed6fc20ecc6362058@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: 76c057c8 Merge branch 'parisc-5.11-2' of git://git.kernel... > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=13728c5f500000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=f75d66d6d359ef2f > > dashboard link: https://syzkaller.appspot.com/bug?extid=51bed6fc20ecc6362058 > > userspace arch: arm64 > > > > 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+51bed6fc20ecc6362058@xxxxxxxxxxxxxxxxxxxxxxxxx > > +Mark > > This happens on arm64 only and pretty frequently. Mark, have you seen > it in your testing? This is qemu emulation, though. I have not seen this, but: * I'm using KVM acceleration (atop a v5.6 host). * I haven't tested v5.11-rc5 specifically. * My config might be different. I use a kconfig fragment to enable a few options atop the latest defconfig: https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/commit/?h=fuzzing/5.10-rc7&id=83abdaa512626051c6eecd7c1dfb41fb061ebcb9 * My Syzkaller instance is older (b6cd37e38acccec1421055549f46948d667f0e60), so it might not be tickling the kernel in the same way. ... and any of those could potentially have some impact. I had just set off a run on v5.11-rc6; I'll update to the latest Syzkaller version and restart that with my config. If that doesn't blow up after a while I can give your config a go on v5.11-rc5. My KVM-accelerated VM is using a PL011 UART as its main UART, but does seem to detect an 8250 UART, so it doesn't look like this is down to VM configuration. Thanks, Mark. > > Internal error: synchronous external abort: 97140050 [#1] PREEMPT SMP > > Modules linked in: > > CPU: 1 PID: 21580 Comm: syz-executor.0 Not tainted 5.11.0-rc5-syzkaller-00040-g76c057c84d28 #0 > > Hardware name: linux,dummy-virt (DT) > > pstate: 80400089 (Nzcv daIf +PAN -UAO -TCO BTYPE=--) > > pc : __raw_writeb arch/arm64/include/asm/io.h:27 [inline] > > pc : _outb include/asm-generic/io.h:501 [inline] > > pc : logic_outb+0x40/0xb0 lib/logic_pio.c:299 > > lr : io_serial_out+0x2c/0x40 drivers/tty/serial/8250/8250_port.c:453 > > sp : ffff80001767bbd0 > > x29: ffff80001767bbd0 x28: f1ff000004267000 > > x27: ffff800014281000 x26: 0000000000000001 > > x25: ffff8000142832a0 x24: ffff800014281000 > > x23: ffff800014281000 x22: 0000000000000fff > > x21: 0000000000000001 x20: 0000000000000002 > > x19: fffffbfffe800001 x18: 00000000fffffffb > > x17: 0000000000000000 x16: 0000000000000000 > > x15: 0000000000000020 x14: ffffffffffffffff > > x13: 0000000000000000 x12: ffff80001767bd9f > > x11: 0000000000000000 x10: 7f7f7f7f7f7f7f7f > > x9 : fefefefefeff3252 x8 : ffff80001767b924 > > x7 : 0000000000000003 x6 : 0000000000000001 > > x5 : f1ff000005d7c4e0 x4 : 0000000000000000 > > x3 : ffff800013c02808 x2 : 0000000000000000 > > x1 : fffffbfffe800000 x0 : 0000000000ffbffe > > Call trace: > > _outb include/asm-generic/io.h:501 [inline] > > logic_outb+0x40/0xb0 lib/logic_pio.c:299 > > io_serial_out+0x2c/0x40 drivers/tty/serial/8250/8250_port.c:453 > > serial_out drivers/tty/serial/8250/8250.h:118 [inline] > > serial8250_set_THRI drivers/tty/serial/8250/8250.h:138 [inline] > > __start_tx drivers/tty/serial/8250/8250_port.c:1566 [inline] > > serial8250_start_tx+0x98/0x1c4 drivers/tty/serial/8250/8250_port.c:1666 > > __uart_start.isra.0+0x3c/0x4c drivers/tty/serial/serial_core.c:127 > > uart_start+0x70/0x110 drivers/tty/serial/serial_core.c:137 > > uart_flush_chars+0x14/0x20 drivers/tty/serial/serial_core.c:573 > > __receive_buf drivers/tty/n_tty.c:1651 [inline] > > n_tty_receive_buf_common+0x2a0/0xb30 drivers/tty/n_tty.c:1744 > > n_tty_receive_buf+0x18/0x2c drivers/tty/n_tty.c:1773 > > tiocsti drivers/tty/tty_io.c:2203 [inline] > > tty_ioctl+0x5b8/0xe5c drivers/tty/tty_io.c:2577 > > vfs_ioctl fs/ioctl.c:48 [inline] > > __do_sys_ioctl fs/ioctl.c:753 [inline] > > __se_sys_ioctl fs/ioctl.c:739 [inline] > > __arm64_sys_ioctl+0xac/0xf0 fs/ioctl.c:739 > > __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] > > invoke_syscall arch/arm64/kernel/syscall.c:49 [inline] > > el0_svc_common.constprop.0+0x74/0x190 arch/arm64/kernel/syscall.c:159 > > do_el0_svc+0x78/0x90 arch/arm64/kernel/syscall.c:198 > > el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365 > > el0_sync_handler+0x1a8/0x1b0 arch/arm64/kernel/entry-common.c:381 > > el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699 > > Code: d2bfd001 f2df7fe1 f2ffffe1 8b010273 (39000274) > > ---[ end trace 00ba385f910422db ]--- > > > > > > --- > > This report is generated by a bot. It may contain errors. > > See https://goo.gl/tpsmEJ for more information about syzbot. > > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > > > syzbot will keep track of this issue. See: > > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > > > -- > > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/0000000000005ec92c05ba05de1b%40google.com.
