Re: [syzbot] [ntfs3?] INFO: task hung in do_user_addr_fault (3)

Tetsuo Handa
2023-01-02T05:28:18Z

On 2023/01/02 9:54, Hillf Danton wrote:
> Even though folio lock is printed in the call trace of syz-executor394/5222
>
> folio_lock include/linux/pagemap.h:938 [inline]
>
> no lockdep radar exists for it in the sake of lock, which makes it harder
> than expected or impossible to find the cause of task hung reported.

Two sets of same pattern.

#0: ffff88801ee04460 (sb_writers#9){.+.+}-{0:0}, at: do_sendfile+0x61c/0xfd0 fs/read_write.c:1254
#1: ffff888073930ca0 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_update_page+0x72/0x550 mm/filemap.c:2478
#2: ffff888073930860 (&ni->ni_lock/4){+.+.}-{3:3}, at: attr_data_get_block+0x4a6/0x2e40 fs/ntfs3/attrib.c:919

#0: ffff88802c7bc758 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x18f/0x2f0 mm/util.c:518
#1: ffff888073930860 (&ni->ni_lock/4){+.+.}-{3:3}, at: attr_data_get_block+0x4a6/0x2e40 fs/ntfs3/attrib.c:919

#0: ffff88801ee04460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:508
#1: ffff888073930b00 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: do_truncate+0x205/0x300 fs/open.c:63
#2: ffff888073930860 (&ni->ni_lock/4){+.+.}-{3:3}, at: ntfs3_setattr+0x596/0xca0 fs/ntfs3/file.c:696

#0: ffff888021b06460 (sb_writers#9){.+.+}-{0:0}, at: do_sendfile+0x61c/0xfd0 fs/read_write.c:1254
#1: ffff888075aec7a0 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_update_page+0x72/0x550 mm/filemap.c:2478
#2: ffff888075aec360 (&ni->ni_lock/4){+.+.}-{3:3}, at: attr_data_get_block+0x4a6/0x2e40 fs/ntfs3/attrib.c:919

#0: ffff888018eead18 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x18f/0x2f0 mm/util.c:518
#1: ffff888075aec360 (&ni->ni_lock/4){+.+.}-{3:3}, at: attr_data_get_block+0x4a6/0x2e40 fs/ntfs3/attrib.c:919

#0: ffff888021b06460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:508
#1: ffff888075aec600 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: do_truncate+0x205/0x300 fs/open.c:63
#2: ffff888075aec360 (&ni->ni_lock/4){+.+.}-{3:3}, at: ntfs3_setattr+0x596/0xca0 fs/ntfs3/file.c:696

But no hint for syz-executor394/8253.

>> 4 locks held by syz-executor394/8253:

I'd like to know what does 8253 is doing with what locks held.

https://lkml.kernel.org/r/c8893402-d1b2-9fad-3aad-d130c5f5923b@I-love.SAKURA.ne.jp
should help, but still no response from Peter nor Ingo.

Since this patch has an Ack from Waiman Long, may I send this patch to linux.git via my tree?