✗ CI.checkpatch: warning for drm/xe/bmg: Fix NULL-ptr deref during probe on SKUs with no display

[Patchwork]

== Series Details ==

Series: drm/xe/bmg: Fix NULL-ptr deref during probe on SKUs with no display
URL   : https://patchwork.freedesktop.org/series/149746/
State : warning

== Summary ==

+ KERNEL=/kernel
+ git clone https://gitlab.freedesktop.org/drm/maintainer-tools mt
Cloning into 'mt'...
warning: redirecting to https://gitlab.freedesktop.org/drm/maintainer-tools.git/
+ git -C mt rev-list -n1 origin/master
202708c00696422fd217223bb679a353a5936e23
+ cd /kernel
+ git config --global --add safe.directory /kernel
+ git log -n1
commit 19e51401836b51a4d642adbdb839e563d35f13ed
Author: Vivek Kasireddy <vivek.kasireddy at intel.com>
Date:   Mon Jun 2 15:11:18 2025 -0700

    drm/xe/bmg: Fix NULL-ptr deref during probe on SKUs with no display
    
    Some SKUs (or variants) of BMG do not have display capabilities and
    are intended to be used as compute-only devices. The Xe driver is
    expected to work with such devices by probing/initializing all
    other capabilities except display. However, the following crash is
    seen when Xe tries to load:
    
    [  115.582833] BUG: kernel NULL pointer dereference, address: 00000000000005d0
    [  115.589775] #PF: supervisor write access in kernel mode
    [  115.594976] #PF: error_code(0x0002) - not-present page
    [  115.600088] PGD 0 P4D 0
    [  115.602617] Oops: Oops: 0002 [#1] SMP
    [  115.606267] CPU: 14 UID: 0 PID: 1547 Comm: kworker/14:3 Tainted: G     U      E       6.15.0-local+ #62 PREEMPT(voluntary)
    [  115.617332] Tainted: [U]=USER, [E]=UNSIGNED_MODULE
    [  115.622100] Hardware name: Intel Corporation Meteor Lake Client Platform/MTL-P DDR5 SODIMM SBS RVP, BIOS MTLPEMI1.R00.3471.D49.2401260852 01/26/2024
    [  115.635314] Workqueue: pm pm_runtime_work
    [  115.639309] RIP: 0010:_raw_spin_lock+0x17/0x30
    [  115.662382] RSP: 0018:ffffd13f82e7bc30 EFLAGS: 00010246
    [  115.667581] RAX: 0000000000000000 RBX: ffff8be919076000 RCX: 0000000000000002
    [  115.674675] RDX: 0000000000000001 RSI: 000000000000004b RDI: 00000000000005d0
    [  115.681775] RBP: ffffd13f82e7bc60 R08: ffffd13f82e7bb00 R09: ffff8beb0c1b06c0
    [  115.688869] R10: ffff8be7c034f4c0 R11: fefefefefefefeff R12: fffffffffffffff0
    [  115.695965] R13: ffff8be9190762e8 R14: ffff8be919077798 R15: 00000000000005d0
    [  115.703062] FS:  0000000000000000(0000) GS:ffff8beb552b6000(0000) knlGS:0000000000000000
    [  115.711106] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    [  115.716826] CR2: 00000000000005d0 CR3: 000000024c68d002 CR4: 0000000000f72ef0
    [  115.723921] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    [  115.731015] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400
    [  115.738113] PKRU: 55555554
    [  115.740816] Call Trace:
    [  115.743258]  <TASK>
    [  115.745363]  ? xe_display_flush_cleanup_work+0x92/0x120 [xe]
    [  115.751102]  xe_display_pm_runtime_suspend+0x42/0x80 [xe]
    [  115.756542]  xe_pm_runtime_suspend+0x11b/0x1b0 [xe]
    [  115.761463]  xe_pci_runtime_suspend+0x23/0xd0 [xe]
    [  115.766291]  pci_pm_runtime_suspend+0x6b/0x1a0
    [  115.770717]  ? pci_pm_thaw_noirq+0xa0/0xa0
    [  115.774797]  __rpm_callback+0x48/0x1e0
    [  115.778531]  ? pci_pm_thaw_noirq+0xa0/0xa0
    [  115.782614]  rpm_callback+0x66/0x70
    [  115.786090]  ? pci_pm_thaw_noirq+0xa0/0xa0
    [  115.790173]  rpm_suspend+0xe1/0x5e0
    [  115.793647]  ? psi_task_switch+0xb8/0x200
    [  115.797643]  ? finish_task_switch.isra.0+0x8d/0x270
    [  115.802502]  pm_runtime_work+0xa6/0xc0
    [  115.806238]  process_one_work+0x186/0x350
    [  115.810234]  worker_thread+0x33a/0x480
    [  115.813968]  ? process_one_work+0x350/0x350
    [  115.818132]  kthread+0x10c/0x220
    [  115.821350]  ? kthreads_online_cpu+0x120/0x120
    [  115.825774]  ret_from_fork+0x3a/0x60
    [  115.829339]  ? kthreads_online_cpu+0x120/0x120
    [  115.833768]  ret_from_fork_asm+0x11/0x20
    [  115.829339]  ? kthreads_online_cpu+0x120/0x120
    [  115.833768]  ret_from_fork_asm+0x11/0x20
    [  115.837680]  </TASK>
    [  115.839907]  acpi_tad(E) drm(E)
    [  115.931629] CR2: 00000000000005d0
    [  115.934935] ---[ end trace 0000000000000000 ]---
    [  115.939531] RIP: 0010:_raw_spin_lock+0x17/0x30
    
    Therefore, to fix this issue, we need to make intel_display_device_probe()
    return NULL if it does not detect the presence of display and ensure
    that its callers check for non-NULL display object before probing other
    display related capabilities.
    
    Cc: Jani Nikula <jani.nikula at intel.com>
    Cc: Matt Roper <matthew.d.roper at intel.com>
    Cc: Lucas De Marchi <lucas.demarchi at intel.com>
    Signed-off-by: Vivek Kasireddy <vivek.kasireddy at intel.com>
+ /mt/dim checkpatch 354657e88d7ab7195b5f0525bc14273fb020f2f2 drm-intel
19e51401836b drm/xe/bmg: Fix NULL-ptr deref during probe on SKUs with no display
-:135: WARNING:MISSING_FIXES_TAG: The commit message has 'Call Trace:', perhaps it also needs a 'Fixes:' tag?

total: 0 errors, 1 warnings, 0 checks, 39 lines checked