[syzbot] [mm?] WARNING in page_vma_mapped_walk

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: df964ce9ef9f Add linux-next specific files for 20230929
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17fed5e1680000
kernel config: https://syzkaller.appspot.com/x/.config?x=880c828d75e38e1b
dashboard link: https://syzkaller.appspot.com/bug?extid=dcf3f48f4bfe47a2f80a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fe7244c6057d/disk-df964ce9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/48cdc7f3b2c0/vmlinux-df964ce9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ce7c93a66da9/bzImage-df964ce9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dcf3f4...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 8436 at include/linux/hugetlb.h:1289 hugetlb_walk include/linux/hugetlb.h:1289 [inline]
WARNING: CPU: 1 PID: 8436 at include/linux/hugetlb.h:1289 page_vma_mapped_walk+0x1e85/0x27a0 mm/page_vma_mapped.c:199
Modules linked in:
CPU: 1 PID: 8436 Comm: syz-executor.0 Not tainted 6.6.0-rc3-next-20230929-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:hugetlb_walk include/linux/hugetlb.h:1289 [inline]
RIP: 0010:page_vma_mapped_walk+0x1e85/0x27a0 mm/page_vma_mapped.c:199
Code: 00 be ff ff ff ff 48 81 c7 a0 01 00 00 e8 33 71 77 08 31 ff 89 c5 89 c6 e8 78 b5 b9 ff 85 ed 0f 85 64 f7 ff ff e8 fb b9 b9 ff <0f> 0b e9 58 f7 ff ff e8 ef b9 b9 ff 48 89 ef 48 81 e7 00 f0 ff ff
RSP: 0000:ffffc90004f0f6b8 EFLAGS: 00010283
RAX: 000000000001b5c2 RBX: ffff88801eca2710 RCX: ffffc9000a691000
RDX: 0000000000040000 RSI: ffffffff81ce9bc5 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 000000000000002f R12: 0000000000200000
R13: ffffffff92312af8 R14: ffffc90004f0f8c0 R15: ffffffff92312b90
FS: 00007f489c7ce6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31a24000 CR3: 0000000017fc0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
try_to_migrate_one+0x4a2/0x28b0 mm/rmap.c:1929
rmap_walk_anon+0x225/0x570 mm/rmap.c:2501
rmap_walk mm/rmap.c:2578 [inline]
rmap_walk mm/rmap.c:2573 [inline]
try_to_migrate+0x2b6/0x300 mm/rmap.c:2230
unmap_and_move_huge_page mm/migrate.c:1421 [inline]
migrate_hugetlbs mm/migrate.c:1547 [inline]
migrate_pages+0xa42/0x27c0 mm/migrate.c:1901
migrate_to_node mm/mempolicy.c:1097 [inline]
do_migrate_pages+0x2e9/0x670 mm/mempolicy.c:1196
kernel_migrate_pages+0x59b/0x780 mm/mempolicy.c:1682
__do_sys_migrate_pages mm/mempolicy.c:1701 [inline]
__se_sys_migrate_pages mm/mempolicy.c:1697 [inline]
__x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1697
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f489ba7cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f489c7ce0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000100
RAX: ffffffffffffffda RBX: 00007f489bb9c050 RCX: 00007f489ba7cae9
RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: 00007f489bac847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000080 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f489bb9c050 R15: 00007ffcda957698
</TASK>


---
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If the bug is a duplicate of another bug, reply with:
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If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: c9f2baaa18b5 Add linux-next specific files for 20231003
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=17bbfb06680000
kernel config: https://syzkaller.appspot.com/x/.config?x=3fe9c462fee1649f

dashboard link: https://syzkaller.appspot.com/bug?extid=dcf3f48f4bfe47a2f80a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1421389a680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12860a7c680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5361e41384fe/disk-c9f2baaa.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7028b209124d/vmlinux-c9f2baaa.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a167dc667ee5/bzImage-c9f2baaa.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dcf3f4...@syzkaller.appspotmail.com

------------[ cut here ]------------

WARNING: CPU: 0 PID: 5058 at include/linux/hugetlb.h:1289 hugetlb_walk include/linux/hugetlb.h:1289 [inline]
WARNING: CPU: 0 PID: 5058 at include/linux/hugetlb.h:1289 page_vma_mapped_walk+0x1eb6/0x27d0 mm/page_vma_mapped.c:199
Modules linked in:
CPU: 0 PID: 5058 Comm: syz-executor350 Not tainted 6.6.0-rc4-next-20231003-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:hugetlb_walk include/linux/hugetlb.h:1289 [inline]

RIP: 0010:page_vma_mapped_walk+0x1eb6/0x27d0 mm/page_vma_mapped.c:199
Code: 00 be ff ff ff ff 48 81 c7 a0 01 00 00 e8 72 64 77 08 31 ff 89 c5 89 c6 e8 27 ac b9 ff 85 ed 0f 85 95 f6 ff ff e8 aa b0 b9 ff <0f> 0b e9 89 f6 ff ff e8 9e b0 b9 ff 48 89 ef 48 81 e7 00 f0 ff ff
RSP: 0018:ffffc90003a5f6c0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88802184b310 RCX: ffffffff81cea839
RDX: ffff88801d870000 RSI: ffffffff81cea846 RDI: 0000000000000005

RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000009 R12: 0000000000200000
R13: ffffffff92315af8 R14: ffffc90003a5f8c0 R15: ffffffff92315b90
FS: 00005555564ba380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000000020000080 CR3: 0000000078ecd000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>

try_to_migrate_one+0x4a2/0x28b0 mm/rmap.c:1950
rmap_walk_anon+0x225/0x570 mm/rmap.c:2522
rmap_walk mm/rmap.c:2599 [inline]
rmap_walk mm/rmap.c:2594 [inline]
try_to_migrate+0x2b6/0x300 mm/rmap.c:2251

unmap_and_move_huge_page mm/migrate.c:1421 [inline]
migrate_hugetlbs mm/migrate.c:1547 [inline]
migrate_pages+0xa42/0x27c0 mm/migrate.c:1901
migrate_to_node mm/mempolicy.c:1097 [inline]
do_migrate_pages+0x2e9/0x670 mm/mempolicy.c:1196

kernel_migrate_pages+0x59b/0x780 mm/mempolicy.c:1681
__do_sys_migrate_pages mm/mempolicy.c:1700 [inline]
__se_sys_migrate_pages mm/mempolicy.c:1696 [inline]
__x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1696

do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd

RIP: 0033:0x7f7a6faa32e9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffed8e03b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000100
RAX: ffffffffffffffda RBX: 00007ffed8e03d18 RCX: 00007f7a6faa32e9

RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000000

RBP: 00007f7a6fb16610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000080 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffed8e03d08 R14: 0000000000000001 R15: 0000000000000001
</TASK>


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[Hillf Danton]

On Tue, 03 Oct 2023 21:37:43 -0700

> HEAD commit: c9f2baaa18b5 Add linux-next specific files for 20231003
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12860a7c680000

Lock huge vma in the cow case.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git c9f2baaa18b5

--- x/mm/hugetlb.c
+++ y/mm/hugetlb.c
@@ -4923,6 +4923,7 @@ int copy_hugetlb_page_range(struct mm_st
src_vma->vm_end);
mmu_notifier_invalidate_range_start(&range);
vma_assert_write_locked(src_vma);
+ hugetlb_vma_lock_write(src_vma);
raw_write_seqcount_begin(&src->write_protect_seq);
} else {
/*
@@ -5084,6 +5085,7 @@ again:

if (cow) {
raw_write_seqcount_end(&src->write_protect_seq);
+ hugetlb_vma_unlock_write(src_vma);
mmu_notifier_invalidate_range_end(&range);
} else {
hugetlb_vma_unlock_read(src_vma);
--- x/mm/rmap.c
+++ y/mm/rmap.c
@@ -1946,6 +1946,8 @@ static bool try_to_migrate_one(struct fo
hsz = huge_page_size(hstate_vma(vma));
}
mmu_notifier_invalidate_range_start(&range);
+ if (vma->vm_file)
+ filemap_invalidate_lock(vma->vm_file->f_mapping);

while (page_vma_mapped_walk(&pvmw)) {
#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
@@ -2200,6 +2202,8 @@ static bool try_to_migrate_one(struct fo
folio_put(folio);
}

+ if (vma->vm_file)
+ filemap_invalidate_unlock(vma->vm_file->f_mapping);
mmu_notifier_invalidate_range_end(&range);

return ret;
--

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in try_to_migrate_one

======================================================
WARNING: possible circular locking dependency detected
6.6.0-rc4-next-20231003-syzkaller-dirty #0 Not tainted
------------------------------------------------------
syz-executor.0/5480 is trying to acquire lock:
ffff8880156a0df8 (mapping.invalidate_lock#3){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:847 [inline]
ffff8880156a0df8 (mapping.invalidate_lock#3){++++}-{3:3}, at: try_to_migrate_one+0x4ac/0x29e0 mm/rmap.c:1950

but task is already holding lock:
ffff88807f7f58f8 (&anon_vma->rwsem){++++}-{3:3}, at: folio_lock_anon_vma_read+0x187/0xb20 mm/rmap.c:555

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&anon_vma->rwsem){++++}-{3:3}:
down_write+0x93/0x200 kernel/locking/rwsem.c:1579
anon_vma_lock_write include/linux/rmap.h:121 [inline]
__anon_vma_prepare+0xbd/0x550 mm/rmap.c:210
anon_vma_prepare include/linux/rmap.h:164 [inline]
hugetlb_no_page mm/hugetlb.c:5812 [inline]
hugetlb_fault+0x1d04/0x24a0 mm/hugetlb.c:5999
handle_mm_fault+0x905/0xa00 mm/memory.c:5430
do_user_addr_fault+0x3d1/0x1000 arch/x86/mm/fault.c:1413
handle_page_fault arch/x86/mm/fault.c:1505 [inline]
exc_page_fault+0x5c/0xd0 arch/x86/mm/fault.c:1561
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

-> #0 (mapping.invalidate_lock#3){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3868 [inline]
__lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136
lock_acquire kernel/locking/lockdep.c:5753 [inline]
lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718
down_write+0x93/0x200 kernel/locking/rwsem.c:1579
filemap_invalidate_lock include/linux/fs.h:847 [inline]
try_to_migrate_one+0x4ac/0x29e0 mm/rmap.c:1950
rmap_walk_anon+0x225/0x570 mm/rmap.c:2526
rmap_walk mm/rmap.c:2603 [inline]
rmap_walk mm/rmap.c:2598 [inline]
try_to_migrate+0x2b6/0x300 mm/rmap.c:2255

unmap_and_move_huge_page mm/migrate.c:1421 [inline]
migrate_hugetlbs mm/migrate.c:1547 [inline]
migrate_pages+0xa42/0x27c0 mm/migrate.c:1901
migrate_to_node mm/mempolicy.c:1097 [inline]
do_migrate_pages+0x2e9/0x670 mm/mempolicy.c:1196
kernel_migrate_pages+0x59b/0x780 mm/mempolicy.c:1681
__do_sys_migrate_pages mm/mempolicy.c:1700 [inline]
__se_sys_migrate_pages mm/mempolicy.c:1696 [inline]
__x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1696
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
rlock(&anon_vma->rwsem);
lock(mapping.invalidate_lock#3);
lock(&anon_vma->rwsem);
lock(mapping.invalidate_lock#3);

*** DEADLOCK ***

2 locks held by syz-executor.0/5480:
#0: ffff888025bd1e20 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:146 [inline]
#0: ffff888025bd1e20 (&mm->mmap_lock){++++}-{3:3}, at: do_migrate_pages+0xc8/0x670 mm/mempolicy.c:1121
#1: ffff88807f7f58f8 (&anon_vma->rwsem){++++}-{3:3}, at: folio_lock_anon_vma_read+0x187/0xb20 mm/rmap.c:555

stack backtrace:
CPU: 0 PID: 5480 Comm: syz-executor.0 Not tainted 6.6.0-rc4-next-20231003-syzkaller-dirty #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023

Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3868 [inline]
__lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136
lock_acquire kernel/locking/lockdep.c:5753 [inline]
lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718
down_write+0x93/0x200 kernel/locking/rwsem.c:1579
filemap_invalidate_lock include/linux/fs.h:847 [inline]
try_to_migrate_one+0x4ac/0x29e0 mm/rmap.c:1950
rmap_walk_anon+0x225/0x570 mm/rmap.c:2526
rmap_walk mm/rmap.c:2603 [inline]
rmap_walk mm/rmap.c:2598 [inline]
try_to_migrate+0x2b6/0x300 mm/rmap.c:2255

unmap_and_move_huge_page mm/migrate.c:1421 [inline]
migrate_hugetlbs mm/migrate.c:1547 [inline]
migrate_pages+0xa42/0x27c0 mm/migrate.c:1901
migrate_to_node mm/mempolicy.c:1097 [inline]
do_migrate_pages+0x2e9/0x670 mm/mempolicy.c:1196
kernel_migrate_pages+0x59b/0x780 mm/mempolicy.c:1681
__do_sys_migrate_pages mm/mempolicy.c:1700 [inline]
__se_sys_migrate_pages mm/mempolicy.c:1696 [inline]
__x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1696
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd

RIP: 0033:0x7fce6d67cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fce6e47d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000100
RAX: ffffffffffffffda RBX: 00007fce6d79bf80 RCX: 00007fce6d67cae9

RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000000

RBP: 00007fce6d6c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000080 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fce6d79bf80 R15: 00007ffe82a8ede8
</TASK>


Tested on:

commit: c9f2baaa Add linux-next specific files for 20231003
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=135c1b8a680000

kernel config: https://syzkaller.appspot.com/x/.config?x=3fe9c462fee1649f
dashboard link: https://syzkaller.appspot.com/bug?extid=dcf3f48f4bfe47a2f80a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=1712a3f6680000

[syzbot]

syzbot has bisected this issue to:

commit 446503572dc452fc544d6898113feb0f3801477b
Author: Rik van Riel <ri...@surriel.com>
Date: Sun Oct 1 00:55:50 2023 +0000

hugetlbfs: replace hugetlb_vma_lock with invalidate_lock

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12c93c16680000
start commit: c9f2baaa18b5 Add linux-next specific files for 20231003
git tree: linux-next
final oops: https://syzkaller.appspot.com/x/report.txt?x=11c93c16680000
console output: https://syzkaller.appspot.com/x/log.txt?x=16c93c16680000

kernel config: https://syzkaller.appspot.com/x/.config?x=3fe9c462fee1649f
dashboard link: https://syzkaller.appspot.com/bug?extid=dcf3f48f4bfe47a2f80a

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1421389a680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12860a7c680000

Reported-by: syzbot+dcf3f4...@syzkaller.appspotmail.com
Fixes: 446503572dc4 ("hugetlbfs: replace hugetlb_vma_lock with invalidate_lock")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.