From mboxrd@z Thu Jan 1 00:00:00 1970 From: Claude Code Review Bot To: dri-devel-reviews@example.com Subject: Claude review: User readable error codes on atomic_ioctl failure Date: Wed, 11 Feb 2026 16:31:46 +1000 Message-ID: In-Reply-To: <20260210-atomic-v9-0-525c88fd2402@intel.com> References: <20260210-atomic-v9-0-525c88fd2402@intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Mailer: Claude Code Patch Reviewer Overall Series Review Subject: User readable error codes on atomic_ioctl failure Author: Arun R Murthy Patches: 8 Reviewed: 2026-02-11T16:31:46.766206 --- This v9 patch series introduces user-readable error reporting for DRM atomic ioctl failures. The goal is to provide compositors with detailed error codes instead of generic -EINVAL, enabling better error handling and recovery. **Series-level Concerns:** 1. **UAPI Misuse of Reserved Field**: The series reuses the `reserved` field in `struct drm_mode_atomic` to pass error information back to userspace. This is problematic: - The field is checked to be zero on entry (patch 3 removes this check) - Repurposing `reserved` breaks the original design intent and may cause issues with existing userspace - Cover letter says "Once the series is merged the element 'reserved' used for sending the failure code in struct drm_mode_atomic is to changed to err_code" - this suggests the naming is wrong but the ABI is being established incorrectly 2. **Memory Allocation Ordering Change**: Patch 3 moves `drm_atomic_state_alloc()` to the beginning of the ioctl, which means state allocation happens before validation checks. This could impact performance in error cases and changes error paths significantly. 3. **Incomplete Coverage**: Only Intel i915 driver errors are implemented (patch 6). The TODO in the cover letter admits driver-specific errors will come later, making this series incomplete for general use. 4. **Error Code Granularity**: The error codes defined are quite coarse-grained and may not provide enough detail for compositors to make intelligent decisions. 5. **v9 Changelog Missing**: Cover letter says "EDITME: describe what is new in this series revision" - the v9 changes are not documented. --- Generated by Claude Code Patch Reviewer