Crash with latest available kernel linux/6.17.0-7.7 when accessing
/sys/kernel/tracing/rv/enabled_monitors:

$ sudo cat /sys/kernel/tracing/rv/enabled_monitors
[ 1295.472802] UBSAN: invalid-load in 
/build/linux-8YMEfB/linux-6.17.0/kernel/trace/rv/rv.c:503:10
[ 1295.477607] load of value 247 is not a valid value for type '_Bool'
[ 1295.492854] BUG: unable to handle page fault for address: 0000000a800001f7
[ 1295.493756] #PF: supervisor read access in kernel mode
[ 1295.494099] #PF: error_code(0x0000) - not-present page
[ 1295.494604] PGD 0 P4D 0 
[ 1295.496689] Oops: Oops: 0000 [#1] SMP NOPTI
[ 1295.497106] CPU: 2 UID: 0 PID: 1506 Comm: cat Not tainted 6.17.0-7-generic 
#7-Ubuntu PREEMPT(voluntary) 
[ 1295.497834] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 
1.15.0-1 04/01/2014
[ 1295.498404] RIP: 0010:monitors_show+0x16/0x60
[ 1295.499320] Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 
90 0f 1f 44 00 00 55 48 8b 46 10 48 8b 4e c0 48 89 e5 48 85 c0 74 1f <48> 8b 10 
48 c7 c6 79 3e be 91 e8 5b cc 26 00 31 c0 5d 31 d2 31 c9
[ 1295.500537] RSP: 0018:ffffcb0d4058fa78 EFLAGS: 00000202
[ 1295.500969] RAX: 0000000a800001f7 RBX: 0000000000000000 RCX: 0000000000000000
[ 1295.501405] RDX: 0000000000000000 RSI: ffffffff9261eb78 RDI: ffff8a8b4b30cf00
[ 1295.501800] RBP: ffffcb0d4058fa78 R08: 0000000000000000 R09: 0000000000000000
[ 1295.502143] R10: 0000000000000000 R11: 0000000000000000 R12: ffffcb0d4058fb20
[ 1295.502540] R13: ffff8a8b4554d100 R14: ffff8a8b4b30cf00 R15: ffffffff9261eb78
[ 1295.503282] FS:  00007023dd92ebc0(0000) GS:ffff8a8ce4d7f000(0000) 
knlGS:0000000000000000
[ 1295.503814] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1295.504198] CR2: 0000000a800001f7 CR3: 000000010ebf2000 CR4: 00000000000006f0
[ 1295.504778] Call Trace:
[ 1295.505236]  <TASK>
[ 1295.505454]  seq_read_iter+0x130/0x490
[ 1295.505752]  seq_read+0x11b/0x160
[ 1295.505933]  vfs_read+0xbf/0x3a0
[ 1295.506161]  ksys_read+0x71/0xf0
[ 1295.506384]  __x64_sys_read+0x19/0x30
[ 1295.506627]  x64_sys_call+0x1e95/0x2330
[ 1295.506879]  do_syscall_64+0x81/0xc90
[ 1295.507171]  ? __memcg_slab_free_hook+0x115/0x190
[ 1295.507460]  ? kmem_cache_free+0x4b4/0x4f0
[ 1295.507717]  ? refill_obj_stock+0x149/0x270
[ 1295.508014]  ? refill_obj_stock+0x149/0x270
[ 1295.508280]  ? __memcg_slab_free_hook+0x115/0x190
[ 1295.508581]  ? dentry_free+0x35/0x90
[ 1295.508909]  ? kmem_cache_free+0x4b4/0x4f0
[ 1295.509201]  ? __fput+0x1a2/0x2d0
[ 1295.509537]  ? __fput+0x1a2/0x2d0
[ 1295.509791]  ? fput_close_sync+0x40/0xc0
[ 1295.510038]  ? __x64_sys_close+0x3e/0x90
[ 1295.510248]  ? arch_exit_to_user_mode_prepare.isra.0+0xd/0xe0
[ 1295.510636]  ? do_syscall_64+0xb9/0xc90
[ 1295.510851]  ? exc_page_fault+0x90/0x1b0
[ 1295.511124]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 1295.515590] RIP: 0033:0x7023dd6a0186
[ 1295.517613] Code: 47 ba 04 00 00 00 48 8b 05 87 3c 19 00 64 89 10 48 c7 c2 
ff ff ff ff c9 48 89 d0 c3 0f 1f 84 00 00 00 00 00 48 8b 45 10 0f 05 <48> 89 c2 
48 3d 00 f0 ff ff 77 0f c9 48 89 d0 c3 66 2e 0f 1f 84 00
[ 1295.521139] RSP: 002b:00007ffc8c2fc3e0 EFLAGS: 00000202 ORIG_RAX: 
0000000000000000
[ 1295.522786] RAX: ffffffffffffffda RBX: 00007ffc8c30c550 RCX: 00007023dd6a0186
[ 1295.524356] RDX: 0000000000010000 RSI: 00007ffc8c2fc430 RDI: 0000000000000003
[ 1295.526083] RBP: 00007ffc8c2fc3f0 R08: 0000000000000000 R09: 0000000000000000
[ 1295.527835] R10: 0000000000000000 R11: 0000000000000202 R12: 8000000000000006
[ 1295.530830] R13: 00007ffc8c2fc430 R14: 00007ffc8c30c4e0 R15: 0000559e6b08f000
[ 1295.532904]  </TASK>
[ 1295.534976] Modules linked in: tls qrtr cfg80211 isofs binfmt_misc 
nls_iso8859_1 kvm_amd ccp ppdev kvm parport_pc irqbypass parport i2c_piix4 
i2c_smbus input_leds mac_hid sch_fq_codel dm_multipath msr efi_pstore nfnetlink 
vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock 
vmw_vmci dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 btrfs blake2b_generic 
raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor 
raid6_pq raid1 raid0 linear vga16fb vgastate psmouse virtio_rng serio_raw bochs 
floppy pata_acpi
[ 1295.544676] CR2: 0000000a800001f7
[ 1295.548932] ---[ end trace 0000000000000000 ]---
[ 1295.551251] RIP: 0010:monitors_show+0x16/0x60
[ 1295.553100] Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 
90 0f 1f 44 00 00 55 48 8b 46 10 48 8b 4e c0 48 89 e5 48 85 c0 74 1f <48> 8b 10 
48 c7 c6 79 3e be 91 e8 5b cc 26 00 31 c0 5d 31 d2 31 c9
[ 1295.556827] RSP: 0018:ffffcb0d4058fa78 EFLAGS: 00000202
[ 1295.558604] RAX: 0000000a800001f7 RBX: 0000000000000000 RCX: 0000000000000000
[ 1295.560534] RDX: 0000000000000000 RSI: ffffffff9261eb78 RDI: ffff8a8b4b30cf00
[ 1295.562696] RBP: ffffcb0d4058fa78 R08: 0000000000000000 R09: 0000000000000000
[ 1295.564926] R10: 0000000000000000 R11: 0000000000000000 R12: ffffcb0d4058fb20
[ 1295.567360] R13: ffff8a8b4554d100 R14: ffff8a8b4b30cf00 R15: ffffffff9261eb78
[ 1295.569293] FS:  00007023dd92ebc0(0000) GS:ffff8a8ce4d7f000(0000) 
knlGS:0000000000000000
[ 1295.571384] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1295.573591] CR2: 0000000a800001f7 CR3: 000000010ebf2000 CR4: 00000000000006f0
Killed

After upgrading to kernel in -proposed:

$ uname -a
Linux cloudimg 6.17.0-8-generic #8-Ubuntu SMP PREEMPT_DYNAMIC Fri Nov 14 
21:44:46 UTC 2025 x86_64 GNU/Linux
$ sudo cat /sys/kernel/tracing/rv/enabled_monitors
$

Crash is no longer observed.

** Tags removed: verification-needed-questing-linux
** Tags added: verification-done-questing-linux

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2131136

Title:
  crash when reading from /sys/kernel/tracing/rv/enabled_monitors

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2131136/+subscriptions


-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to