Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider: - [High] Calling `xe_device_declare_wedged()` during driver probe silently drops the `WEDGED` uevent because the DRM device is not yet registered in sysfs, and `xe_ras_init()` ignores the disconnect return value, leaving userspace unaware of a permanently wedged device. - [High] Unprotected writes to `xe->wedged.method` cause a data race with concurrent wedge events, which can overwrite the critical `DRM_WEDGE_RECOVERY_COLD_RESET` recovery method, and lack of state checking leads to redundant uevent flooding. --
--- Patch [3]: [PATCH v12 3/4] drm/xe: Handle PUNIT errors by requesting cold-reset recovery --- commit 340a6fc7bdb22fd2c21615ec29270c2b330f42ea Author: Mallesh Koujalagi <[email protected]> drm/xe: Handle PUNIT errors by requesting cold-reset recovery This commit handles PUNIT errors by setting the wedge recovery method to cold reset and declaring the device wedged. This ensures that userspace is notified that a complete device power cycle is required to restore normal operation. > diff --git a/drivers/gpu/drm/xe/xe_ras.c b/drivers/gpu/drm/xe/xe_ras.c > index a31e06b8aa67a..92b4181026cbe 100644 > --- a/drivers/gpu/drm/xe/xe_ras.c > +++ b/drivers/gpu/drm/xe/xe_ras.c > @@ -236,6 +236,12 @@ static u8 handle_core_compute_errors(struct > xe_ras_error_array *arr) > return XE_RAS_RECOVERY_ACTION_RECOVERED; > } > > +static void punit_error_handler(struct xe_device *xe) > +{ > + xe_device_set_wedged_method(xe, DRM_WEDGE_RECOVERY_COLD_RESET); [Severity: High] Does this unprotected write to xe->wedged.method create a data race? If another thread (e.g., PCI AER or GT reset) concurrently calls xe_device_declare_wedged(), it could evaluate if (!xe->wedged.method) before this assignment, and overwrite DRM_WEDGE_RECOVERY_COLD_RESET with the default DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET. Also, since xe_ras_process_errors() processes multiple errors in a loop: drivers/gpu/drm/xe/xe_ras.c:xe_ras_process_errors() { ... for (int i = 0; i < response.num_errors && i < XE_RAS_NUM_ERROR_ARR; i++) { // error handler called ... } Will this cause a flood of redundant uevents and wedge method assignments if multiple PUNIT errors are returned in a single response? > + xe_device_declare_wedged(xe); [Severity: High] Can this call silently drop the WEDGED uevent if it occurs during driver probe? If a PUNIT error is detected during early probe via: xe_device_probe() -> xe_ras_init() -> xe_ras_process_errors() -> handle_soc_internal_errors() -> punit_error_handler() The uevent sent by drm_dev_wedged_event() (called from xe_device_declare_wedged()) will fail with -EINVAL because the DRM device is not yet registered in sysfs (kobj->state_in_sysfs is false). Furthermore, since xe_ras_init() ignores the XE_RAS_RECOVERY_ACTION_DISCONNECT return value, will the system boot with a wedged GPU while userspace is completely unaware? > +} [ ... ] -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=3
