syzbot
BUG: unable to handle kernel paging request in drr_qlen_notify
Status:
auto-obsoleted due to no activity on 2025/09/25 00:42
Bug presence:
origin:lts-only
[Documentation on labels]
Reported-by: syzbot+7b701920eca6463ba48b@syzkaller.appspotmail.com
First crash: 390d, last: 384d
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Bug presence (2)
| Date |
Name |
Commit |
Repro |
Result |
| 2025/07/12 |
linux-5.15.y (ToT) |
2f693b607545 |
C
|
[report] BUG: unable to handle kernel paging request in drr_qlen_notify
|
| 2025/07/12 |
upstream (ToT) |
379f604cc3dc |
C
|
Didn't crash |
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Last patch testing requests (1)
| Created |
Duration |
User |
Patch |
Repo |
Result |
| 2025/09/21 09:08 |
19m
|
retest repro
|
|
linux-5.15.y |
OK
log
|
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Fix bisection attempts (1)
Sample crash report:
Unable to handle kernel paging request at virtual address dfff80000000000b
Mem abort info:
ESR = 0x0000000096000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
[dfff80000000000b] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 14966 Comm: syz.3.1632 Not tainted 5.15.188-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __list_del_entry_valid+0x28/0x150 lib/list_debug.c:46
lr : __list_del_entry include/linux/list.h:132 [inline]
lr : list_del include/linux/list.h:146 [inline]
lr : drr_qlen_notify+0x38/0x110 net/sched/sch_drr.c:238
sp : ffff800020306cc0
x29: ffff800020306cc0 x28: 1ffff000025a914c x27: dfff800000000000
x26: 0000000000000000 x25: ffff800012d48a68 x24: ffff800012d48a60
x23: dfff800000000000 x22: ffff8000162edce0 x21: dfff800000000000
x20: 0000000000000050 x19: 0000000000000050 x18: 0000000000000201
x17: 0000000000000002 x16: ffff8000082bf708 x15: 00000000ffffffff
x14: 0000000000ff0100 x13: ffffffffffffffff x12: 0000000000080000
x11: 0000000000000fd0 x10: ffff800027d3e000 x9 : ffff80000f98d928
x8 : 000000000000000b x7 : ffff80000f8d3b08 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000002
x2 : 0000000000000008 x1 : 0000000000000000 x0 : 0000000000000058
Call trace:
__list_del_entry_valid+0x28/0x150 lib/list_debug.c:46
__list_del_entry include/linux/list.h:132 [inline]
list_del include/linux/list.h:146 [inline]
drr_qlen_notify+0x38/0x110 net/sched/sch_drr.c:238
qdisc_tree_reduce_backlog+0x250/0x410 net/sched/sch_api.c:799
codel_change+0x70c/0x9f8 net/sched/sch_codel.c:183
codel_init+0x14c/0x2f0 net/sched/sch_codel.c:202
qdisc_create+0x6e4/0xf24 net/sched/sch_api.c:1260
tc_modify_qdisc+0x8bc/0x1308 net/sched/sch_api.c:-1
rtnetlink_rcv_msg+0x9d4/0xd04 net/core/rtnetlink.c:5650
netlink_rcv_skb+0x208/0x3c4 net/netlink/af_netlink.c:2489
rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:5668
netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
netlink_unicast+0x60c/0x89c net/netlink/af_netlink.c:1337
netlink_sendmsg+0x6e8/0x9cc net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x61c/0x920 net/socket.c:2436
___sys_sendmsg+0x1d0/0x240 net/socket.c:2490
__sys_sendmsg net/socket.c:2519 [inline]
__do_sys_sendmsg net/socket.c:2528 [inline]
__se_sys_sendmsg net/socket.c:2526 [inline]
__arm64_sys_sendmsg+0x1a8/0x254 net/socket.c:2526
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: 91002000 d2d00015 d343fc08 f2fbfff5 (38756908)
---[ end trace c44356469a42dbf0 ]---
----------------
Code disassembly (best guess):
0: 91002000 add x0, x0, #0x8
4: d2d00015 mov x21, #0x800000000000 // #140737488355328
8: d343fc08 lsr x8, x0, #3
c: f2fbfff5 movk x21, #0xdfff, lsl #48
* 10: 38756908 ldrb w8, [x8, x21] <-- trapping instruction
* Struck through repros no longer work on HEAD.