On Wed, Jan 27, 2016 at 7:02 PM, Ross Zwisler <zwisler@xxxxxxxxx> wrote: > On Sun, Jan 24, 2016 at 3:48 AM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: >> Hello, >> >> The following program triggers WARNING in __delete_from_page_cache: >> >> ------------[ cut here ]------------ >> WARNING: CPU: 0 PID: 7676 at mm/filemap.c:217 >> __delete_from_page_cache+0x9f6/0xb60() >> Modules linked in: >> CPU: 0 PID: 7676 Comm: a.out Not tainted 4.4.0+ #276 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> 00000000ffffffff ffff88006d3f7738 ffffffff82999e2d 0000000000000000 >> ffff8800620a0000 ffffffff86473d20 ffff88006d3f7778 ffffffff81352089 >> ffffffff81658d36 ffffffff86473d20 00000000000000d9 ffffea0000009d60 >> Call Trace: >> [< inline >] __dump_stack lib/dump_stack.c:15 >> [<ffffffff82999e2d>] dump_stack+0x6f/0xa2 lib/dump_stack.c:50 >> [<ffffffff81352089>] warn_slowpath_common+0xd9/0x140 kernel/panic.c:482 >> [<ffffffff813522b9>] warn_slowpath_null+0x29/0x30 kernel/panic.c:515 >> [<ffffffff81658d36>] __delete_from_page_cache+0x9f6/0xb60 mm/filemap.c:217 >> [<ffffffff81658fb2>] delete_from_page_cache+0x112/0x200 mm/filemap.c:244 >> [<ffffffff818af369>] __dax_fault+0x859/0x1800 fs/dax.c:487 >> [<ffffffff8186f4f6>] blkdev_dax_fault+0x26/0x30 fs/block_dev.c:1730 >> [< inline >] wp_pfn_shared mm/memory.c:2208 >> [<ffffffff816e9145>] do_wp_page+0xc85/0x14f0 mm/memory.c:2307 >> [< inline >] handle_pte_fault mm/memory.c:3323 >> [< inline >] __handle_mm_fault mm/memory.c:3417 > > Having inline functions represented in the stack trace and having file > names with line numbers seems really useful - how did you get this > output? Is this a feature of some kernel patch applied for syzkaller? I pipe normal kernel output through this script: https://github.com/google/sanitizers/blob/master/address-sanitizer/tools/kasan_symbolize.py If you are in linux source dir with vmlinux and modules, then you just do: $ cat crash | kasan_symbolize.py -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>