diff options
| author |   Lucas De Marchi <lucas.demarchi@intel.com> | 2025-03-07 17:02:01 -0800 |
|---|---|---|
| committer |   Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2025-03-12 21:24:33 +0100 |
| commit | ff63b62d5abd2ce109401a8b57d5e36c4b07a5b1 (patch) | |
| tree | 362ebbc3dccf015e23a0a95d9a8e8ee634dbaba1 | |
| parent | thermal: core: Fix spelling mistake "Occurences" -> "Occurrences" (diff) | |
| download | wireguard-linux-ff63b62d5abd2ce109401a8b57d5e36c4b07a5b1.tar.xz wireguard-linux-ff63b62d5abd2ce109401a8b57d5e36c4b07a5b1.zip | |
thermal: core: Delay exposing sysfs interface
There's a race between initializing the governor and userspace accessing
the sysfs interface. From time to time the Intel graphics CI shows this
signature:
<1>[] #PF: error_code(0x0000) - not-present page
<6>[] PGD 0 P4D 0
<4>[] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
<4>[] CPU: 3 UID: 0 PID: 562 Comm: thermald Not tainted 6.14.0-rc4-CI_DRM_16208-g7e37396f86d8+ #1
<4>[] Hardware name: Intel Corporation Twin Lake Client Platform/AlderLake-N LP5 RVP, BIOS TWLNFWI1.R00.5222.A01.2405290634 05/29/2024
<4>[] RIP: 0010:policy_show+0x1a/0x40
thermald tries to read the policy file between the sysfs files being
created and the governor set by thermal_set_governor(), which causes the
NULL pointer dereference.
Similarly to the hwmon interface, delay exposing the sysfs files to when
the governor is already set.
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13655
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patch.msgid.link/20250307-thermal-sysfs-race-v1-1-8a3d4d4ac9c4@intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | drivers/thermal/thermal_core.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 2328ac0d8561..f96ca2710928 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -1589,26 +1589,26 @@ thermal_zone_device_register_with_trips(const char *type, tz->state = TZ_STATE_FLAG_INIT; + result = dev_set_name(&tz->device, "thermal_zone%d", tz->id); + if (result) + goto remove_id; + + thermal_zone_device_init(tz); + + result = thermal_zone_init_governor(tz); + if (result) + goto remove_id; + /* sys I/F */ /* Add nodes that are always present via .groups */ result = thermal_zone_create_device_groups(tz); if (result) goto remove_id; - result = dev_set_name(&tz->device, "thermal_zone%d", tz->id); - if (result) { - thermal_zone_destroy_device_groups(tz); - goto remove_id; - } - thermal_zone_device_init(tz); result = device_register(&tz->device); if (result) goto release_device; - result = thermal_zone_init_governor(tz); - if (result) - goto unregister; - if (!tz->tzp || !tz->tzp->no_hwmon) { result = thermal_add_hwmon_sysfs(tz); if (result) |