WARNING: suspicious RCU usage in mas

ID	Workflow	Correct	Bug	Created	Started	Finished	Revision	Error
34bd58cb-79d2-44cf-9f1c-d1ad6762aab0	assessment-security	💥	WARNING: suspicious RCU usage in mas_walk (3)	2026/06/18 02:10	2026/06/18 02:10	2026/06/18 02:33	b62b3ded1759f79b37600c5ffe2b0a81b919b0b0	failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/5c3321ab8a8b065fa3... truncated to first 200 bytes; open job for full error
0b7ef070-c5cd-471d-9dcf-6cdb8fc7dfc4	assessment-security	💥	WARNING: suspicious RCU usage in mas_walk (3)	2026/06/09 22:17	2026/06/09 22:17	2026/06/09 22:38	c36c07f6c1f2230a36374cbd22235f635e8f9284	failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/5c3321ab8a8b065fa3... truncated to first 200 bytes; open job for full error
f8e67c91-6542-4d65-9504-50690b3deaf6	assessment-security	💥	WARNING: suspicious RCU usage in mas_walk (3)	2026/06/03 00:02	2026/06/03 00:02	2026/06/03 00:26	62fe15281f5011cd203d8845b8767b10e7443aa5	failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/5c3321ab8a8b065fa3... truncated to first 200 bytes; open job for full error
0d21b33a-6f33-4ca4-9d6b-42fb3a070dad	assessment-security	💥	WARNING: suspicious RCU usage in mas_walk (3)	2026/05/31 18:48	2026/05/31 18:48	2026/05/31 19:11	6b4a844333e83556da95d61d7f207e7ef5cd4bc6	failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/5c3321ab8a8b065fa3... truncated to first 200 bytes; open job for full error
9bc5b050-2f29-47f2-bfb2-a798e8f253a3	assessment-security	💥	WARNING: suspicious RCU usage in mas_walk (3)	2026/05/15 06:11	2026/05/15 06:11	2026/05/15 06:13	6ccb967e465e832a7bfd7a116ad00d52a0923a5d	failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: ... truncated to first 200 bytes; open job for full error

Title	Replies (including bot)	Last reply
[syzbot] [mm?] WARNING: suspicious RCU usage in mas_walk (3)	2 (6)	2023/10/25 00:07
[PATCH] mempolicy: migration attempt to match interleave nodes: fix	2 (2)	2023/10/24 15:18

Title

Replies (including bot)

Last reply

[syzbot] [mm?] WARNING: suspicious RCU usage in mas_walk (3)

2 (6)

2023/10/25 00:07

[PATCH] mempolicy: migration attempt to match interleave nodes: fix

2 (2)

2023/10/24 15:18

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	WARNING: suspicious RCU usage in mas_walk kernfs	4	C	error		234	1182d	1512d	22/29	fixed on 2023/06/08 14:41
upstream	WARNING: suspicious RCU usage in mas_walk (2) mm	4	C	done		97	1057d	1079d	0/29	auto-obsoleted due to no activity on 2023/10/05 22:43

Rank 🛈

upstream

WARNING: suspicious RCU usage in mas_walk kernfs

error

234

1182d

1512d

22/29

fixed on 2023/06/08 14:41

upstream

WARNING: suspicious RCU usage in mas_walk (2) mm

done

1057d

1079d

0/29

auto-obsoleted due to no activity on 2023/10/05 22:43

============================= WARNING: suspicious RCU usage 6.6.0-rc6-next-20231023-syzkaller #0 Not tainted ----------------------------- lib/maple_tree.c:856 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 no locks held by syz-executor445/16542. stack backtrace: CPU: 1 PID: 16542 Comm: syz-executor445 Not tainted 6.6.0-rc6-next-20231023-syzkaller #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+0x125/0x1b0 lib/dump_stack.c:106 lockdep_rcu_suspicious+0x20b/0x3a0 kernel/locking/lockdep.c:6711 mas_root lib/maple_tree.c:856 [inline] mas_root lib/maple_tree.c:854 [inline] mas_start lib/maple_tree.c:1385 [inline] mas_state_walk lib/maple_tree.c:3705 [inline] mas_walk+0x4d1/0x7d0 lib/maple_tree.c:4888 mas_find_setup lib/maple_tree.c:5948 [inline] mas_find+0x1e6/0x400 lib/maple_tree.c:5989 vma_find include/linux/mm.h:952 [inline] do_mbind+0xc8f/0x1010 mm/mempolicy.c:1328 kernel_mbind+0x1d4/0x1f0 mm/mempolicy.c:1486 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a RIP: 0033:0x7f384f7bd229 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 1d 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:00007f384f753158 EFLAGS: 00000212 ORIG_RAX: 00000000000000ed RAX: ffffffffffffffda RBX: 00007f384f8413f8 RCX: 00007f384f7bd229 RDX: 0000000000000003 RSI: 0000000000005000 RDI: 0000000020182000 RBP: 00007f384f8413f0 R08: 000000000000007f R09: 0000000000000003 R10: 0000000020000040 R11: 0000000000000212 R12: 00007f384f8413fc R13: 000000000000006e R14: 00007ffdafb5ca20 R15: 00007ffdafb5cb08 </TASK> ============================= WARNING: suspicious RCU usage 6.6.0-rc6-next-20231023-syzkaller #0 Not tainted ----------------------------- lib/maple_tree.c:812 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 no locks held by syz-executor445/16542. stack backtrace: CPU: 0 PID: 16542 Comm: syz-executor445 Not tainted 6.6.0-rc6-next-20231023-syzkaller #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+0x125/0x1b0 lib/dump_stack.c:106 lockdep_rcu_suspicious+0x20b/0x3a0 kernel/locking/lockdep.c:6711 mt_slot lib/maple_tree.c:812 [inline] mt_slot lib/maple_tree.c:809 [inline] mtree_range_walk+0x6c5/0x9b0 lib/maple_tree.c:2827 mas_state_walk lib/maple_tree.c:3712 [inline] mas_walk+0x374/0x7d0 lib/maple_tree.c:4888 mas_find_setup lib/maple_tree.c:5948 [inline] mas_find+0x1e6/0x400 lib/maple_tree.c:5989 vma_find include/linux/mm.h:952 [inline] do_mbind+0xc8f/0x1010 mm/mempolicy.c:1328 kernel_mbind+0x1d4/0x1f0 mm/mempolicy.c:1486 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a RIP: 0033:0x7f384f7bd229 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 1d 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:00007f384f753158 EFLAGS: 00000212 ORIG_RAX: 00000000000000ed RAX: ffffffffffffffda RBX: 00007f384f8413f8 RCX: 00007f384f7bd229 RDX: 0000000000000003 RSI: 0000000000005000 RDI: 0000000020182000 RBP: 00007f384f8413f0 R08: 000000000000007f R09: 0000000000000003 R10: 0000000020000040 R11: 0000000000000212 R12: 00007f384f8413fc R13: 000000000000006e R14: 00007ffdafb5ca20 R15: 00007ffdafb5cb08 </TASK>

Crashes (12):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2023/10/24 09:31	linux-next	e8361b005d7c	af8d2e46	.config	console log	report	syz	C		[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/23 17:42	linux-next	e8361b005d7c	989a3687	.config	console log	report	syz			[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/23 17:24	linux-next	e8361b005d7c	989a3687	.config	console log	report	syz			[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/24 21:35	linux-next	f017d9a92a73	17e6d526	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/24 16:36	linux-next	f017d9a92a73	af8d2e46	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/24 05:40	linux-next	e8361b005d7c	af8d2e46	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/24 03:02	linux-next	e8361b005d7c	af8d2e46	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/23 14:41	linux-next	e8361b005d7c	989a3687	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/23 12:55	linux-next	e8361b005d7c	989a3687	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/23 10:08	linux-next	e8361b005d7c	361b23dc	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/23 07:42	linux-next	e8361b005d7c	361b23dc	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk
2023/10/06 18:35	linux-next	7d730f1bf6f3	ea12a918	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	WARNING: suspicious RCU usage in mas_walk

Crashes (12):

Assets (help?)