Control: tags -1 + moreinfo Hi Vincent,
On Mon, Sep 29, 2025 at 05:56:05PM +0200, Vincent Lefevre wrote: > Package: src:linux > Version: 6.16.8-1 > Severity: important > > When logging out: > > Sep 29 10:01:20 qaa kernel: ------------[ cut here ]------------ > Sep 29 10:01:20 qaa kernel: UBSAN: shift-out-of-bounds in > /build/reproducible-path/linux-6.16.8/drivers/gpu/drm/display/drm_dp_mst_topology.c:4574:36 > Sep 29 10:01:20 qaa kernel: shift exponent -1 is negative > Sep 29 10:01:20 qaa kernel: CPU: 4 UID: 0 PID: 490795 Comm: Xorg Not tainted > 6.16.8+deb14-amd64 #1 PREEMPT(lazy) Debian 6.16.8-1 > Sep 29 10:01:20 qaa kernel: Hardware name: Dell Inc. Precision 5570/01Y4G1, > BIOS 1.32.1 04/28/2025 > Sep 29 10:01:20 qaa kernel: Call Trace: > Sep 29 10:01:20 qaa kernel: <TASK> > Sep 29 10:01:20 qaa kernel: dump_stack_lvl+0x5d/0x80 > Sep 29 10:01:20 qaa kernel: ubsan_epilogue+0x5/0x2b > Sep 29 10:01:20 qaa kernel: > __ubsan_handle_shift_out_of_bounds.cold+0x5e/0x113 > Sep 29 10:01:20 qaa kernel: drm_dp_atomic_release_time_slots.cold+0x18/0x61 > [drm_display_helper] > Sep 29 10:01:20 qaa kernel: drm_atomic_helper_check_modeset+0x484/0xe30 > [drm_kms_helper] > Sep 29 10:01:20 qaa kernel: intel_atomic_check+0xec/0x2b10 [i915] > Sep 29 10:01:20 qaa kernel: drm_atomic_check_only+0x63a/0xab0 [drm] > Sep 29 10:01:20 qaa kernel: drm_atomic_commit+0x71/0xe0 [drm] > Sep 29 10:01:20 qaa kernel: ? __pfx___drm_printfn_info+0x10/0x10 [drm] > Sep 29 10:01:20 qaa kernel: drm_client_modeset_commit_atomic+0x201/0x250 > [drm] > Sep 29 10:01:20 qaa kernel: drm_client_modeset_commit_locked+0x5a/0x160 [drm] > Sep 29 10:01:20 qaa kernel: ? drm_setup_crtcs_fb+0xfa/0x150 [drm_kms_helper] > Sep 29 10:01:20 qaa kernel: > __drm_fb_helper_restore_fbdev_mode_unlocked+0x5e/0xd0 [drm_kms_helper] > Sep 29 10:01:20 qaa kernel: drm_fb_helper_hotplug_event+0xe6/0x100 > [drm_kms_helper] > Sep 29 10:01:20 qaa kernel: > __drm_fb_helper_restore_fbdev_mode_unlocked+0xbd/0xd0 [drm_kms_helper] > Sep 29 10:01:20 qaa kernel: drm_fb_helper_set_par+0x30/0x40 [drm_kms_helper] > Sep 29 10:01:20 qaa kernel: intel_fbdev_set_par+0x38/0x80 [i915] > Sep 29 10:01:20 qaa kernel: fb_set_var+0x248/0x430 > Sep 29 10:01:20 qaa kernel: ? __slab_free+0xdf/0x310 > Sep 29 10:01:20 qaa kernel: ? __slab_free+0xdf/0x310 > Sep 29 10:01:20 qaa kernel: ? __slab_free+0xdf/0x310 > Sep 29 10:01:20 qaa kernel: fbcon_blank+0x28e/0x390 > Sep 29 10:01:20 qaa kernel: do_unblank_screen+0xd6/0x1e0 > Sep 29 10:01:20 qaa kernel: vt_ioctl+0x583/0x15b0 > Sep 29 10:01:20 qaa kernel: tty_ioctl+0xe8/0x8c0 > Sep 29 10:01:20 qaa kernel: __x64_sys_ioctl+0x93/0xe0 > Sep 29 10:01:20 qaa kernel: do_syscall_64+0x84/0x320 > Sep 29 10:01:20 qaa kernel: ? __x64_sys_close+0x3d/0x80 > Sep 29 10:01:20 qaa kernel: ? kmem_cache_free+0x3a3/0x450 > Sep 29 10:01:20 qaa kernel: ? do_syscall_64+0x30c/0x320 > Sep 29 10:01:20 qaa kernel: ? do_user_addr_fault+0x2c3/0x7f0 > Sep 29 10:01:20 qaa kernel: entry_SYSCALL_64_after_hwframe+0x76/0x7e > Sep 29 10:01:20 qaa kernel: RIP: 0033:0x7f8285d648db > Sep 29 10:01:20 qaa kernel: Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 > 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 > 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 > Sep 29 10:01:20 qaa kernel: RSP: 002b:00007ffec1647a00 EFLAGS: 00000246 > ORIG_RAX: 0000000000000010 > Sep 29 10:01:20 qaa kernel: RAX: ffffffffffffffda RBX: 000055fbd6e6ab80 RCX: > 00007f8285d648db > Sep 29 10:01:20 qaa kernel: RDX: 0000000000000000 RSI: 0000000000004b3a RDI: > 000000000000000e > Sep 29 10:01:20 qaa kernel: RBP: 0000000000000000 R08: 0000000000000000 R09: > 0000000000000000 > Sep 29 10:01:20 qaa kernel: R10: 0000000000000000 R11: 0000000000000246 R12: > 000055fbd6ea5794 > Sep 29 10:01:20 qaa kernel: R13: 00007ffec1647c48 R14: 000055fbd6e90c10 R15: > 000055fbd6e90bf8 > Sep 29 10:01:20 qaa kernel: </TASK> > Sep 29 10:01:20 qaa kernel: ---[ end trace ]--- > > What I did: > * Earlier, the laptop was connected to a dock. > * I logged out. > * I disconnected the machine from the dock. > * I closed the lid, which suspended the machine as expected: > Sep 29 09:19:53 qaa systemd-logind[1241]: Lid closed. > Sep 29 09:19:53 qaa systemd-logind[1241]: Suspending... > > The above occurred after I opened the lid. Assuming you can reproduce this, can you test the patch from https://lore.kernel.org/all/[email protected]/ and report back if that fixes the issue? In case it does, can you please followup to the upstream patch sumission adding your Tested-by (and ideally get as well a Closes tag for this bug for easier tracking). I might be completely wrong on it. Regards, Salvatore
