From: Shiju Jose <shiju.jose@xxxxxxxxxx> Support for CXL memory EDAC features: patrol scrub, ECS, soft-PPR and memory sparing. Detailed history of the complete EDAC series with CXL EDAC patches[1]. The code is based on [2] v6.15-rc4. 1. https://lore.kernel.org/linux-cxl/20250212143654.1893-1-shiju.jose@xxxxxxxxxx/ 2. https://github.com/torvalds/linux.git Userspace code for CXL memory repair features [3] and sample boot-script for CXL memory repair [4]. [3]: https://lore.kernel.org/lkml/20250207143028.1865-1-shiju.jose@xxxxxxxxxx/ [4]: https://lore.kernel.org/lkml/20250207143028.1865-5-shiju.jose@xxxxxxxxxx/ Changes ======= v4 -> v5: 1. Fixed a compilation warning introduced by v3->v4, reported by Dave Jiang on v4. drivers/cxl/core/edac.c: In function ‘cxl_mem_perform_sparing’: drivers/cxl/core/edac.c:1335:29: warning: the comparison will always evaluate as ‘true’ for the address of ‘validity_flags’ will never be NULL [-Waddress] 1335 | if (!rec->media_hdr.validity_flags) | ^ In file included from ./drivers/cxl/cxlmem.h:10, from drivers/cxl/core/edac.c:21: ./include/cxl/event.h:35:12: note: ‘validity_flags’ declared here 35 | u8 validity_flags[2]; | ^~~~~~~~~~~~~~ 2. Updated patches for tags given. v3 -> v4: 1. Feedback from Dave Jiang on v3, 1.1. Changes for comments in EDAC scrub documentation for CXL use cases. https://lore.kernel.org/all/2df68c68-f1a8-4327-abc9-d265326c133d@xxxxxxxxx/ 1.2. Changes for comments in CXL memory sparing control feature. https://lore.kernel.org/all/4ee3323c-fb27-4fbe-b032-78fd54bc21a0@xxxxxxxxx/ v2 -> v3: 1. Feedback from Dan Williams on v2, https://lore.kernel.org/linux-mm/20250320180450.539-1-shiju.jose@xxxxxxxxxx/ - Modified get_support_feature_info() in fwctl series generic to use in cxl/fxctl and cxl/edac and replace cxl_get_feature_entry() in the CXL edac series. - Add usecase note for CXL ECS in Documentation/edac/scrub.rst. - Add info message when device scrub rate set by a region overwritten with a local device scrub rate or another region's scrub rate. - Replace 'ps' with patrol_scrub in the patrol scrub feature. - Replaced usage of intermediate objects struct cxl_memdev_ps_params and enum cxl_scrub_param etc for patrol scrub and did same for ECS. - Rename CXL_MEMDEV_PS_* macros. - Rename scrub_cycle_hrs-> scrub_cycle_hours - Add if (!cxl_dev_name) return -ENOMEM; to devm_cxl_memdev_edac_register() - Add devm_cxl_region_edac_register(cxlr) for CXL_PARTMODE_PMEM case. - Add separate configurations for CXL scrub, ECS and memory repair CXL_EDAC_SCRUB, CXL_EDAC_ECS and CXL_EDAC_MEM_REPAIR. - Add if (!capable(CAP_SYS_RAWIO)) return -EPERM; for set attributes callbacks for CXL scrub, ECS and memory repair. - In patch "cxl/mbox: Add support for PERFORM_MAINTENANCE mailbox command" * cxl_do_maintenance() -> cxl_perform_maintenance() and moved to cxl/core/edac.c * kmalloc() -> kvzalloc() - In patch, "cxl: Support for finding memory operation attributes from the current boot" * Moved code from drivers/cxl/core/ras.c to drivers/cxl/core/edac.c * Add few logics to releasing the cache to give safety with respect to error storms and burning * unlimited memory. * Add estimated memory overhead expense of this feature documented in the Kconfig. * Unified various names such as attr, param, attrbs throughout the patches. * Moved > struct xarray rec_gen_media and struct xarray rec_dram; out of struct cxl_memdev to CXL edac object, but there is required a pointer to this object in struct cxl_memdev because the error records are reported and thus stored in the cxl_memdev context not in the CXL EDAC context. 2. Feedback from Borislav on v2, - In include/linux/edac.h Replace EDAC_PPR -> EDAC_REPAIR_PPR EDAC_CACHELINE_SPARING -> EDAC_REPAIR_CACHELINE_SPARING etc. v1 -> v2: 1. Feedback from Dan Williams on v1, https://lore.kernel.org/linux-mm/20250307091137.00006a0a@xxxxxxxxxx/T/ - Fixed lock issues in region scrubbing, added local cxl_acquire() and cxl_unlock. - Replaced CXL examples using cat and echo from EDAC .rst docs with short description and ref to ABI docs. Also corrections in existing descriptions as suggested by Dan. - Add policy description for the scrub control feature. However this may require inputs from CXL experts. - Replaced CONFIG_CXL_RAS_FEATURES with CONFIG_CXL_EDAC_MEM_FEATURES. - Few changes to depends part of CONFIG_CXL_EDAC_MEM_FEATURES. - Rename drivers/cxl/core/memfeatures.c as drivers/cxl/core/edac.c - snprintf() -> kasprintf() in few places. 2. Feedback from Alison on v1, - In cxl_get_feature_entry()(patch 1), return NULL on failures and reintroduced checks in cxl_get_feature_entry(). - Changed logic in for loop in region based scrubbing code. - Replace cxl_are_decoders_committed() to cxl_is_memdev_memory_online() and add as a local function to drivers/cxl/core/edac.c - Changed few multiline comments to single line comments. - Removed unnecessary comments from the code. - Reduced line length of few macros in ECS and memory repair code. - In new files, changed "GPL-2.0-or-later" -> "GPL-2.0-only". - Ran clang-format for new files and updated. 3. Changes for feedbacks from Jonathan on v1. - Changed few multiline comments to single line comments. Shiju Jose (8): EDAC: Update documentation for the CXL memory patrol scrub control feature cxl: Update prototype of function get_support_feature_info() cxl/edac: Add CXL memory device patrol scrub control feature cxl/edac: Add CXL memory device ECS control feature cxl/edac: Add support for PERFORM_MAINTENANCE command cxl/edac: Support for finding memory operation attributes from the current boot cxl/edac: Add CXL memory device memory sparing control feature cxl/edac: Add CXL memory device soft PPR control feature Documentation/edac/memory_repair.rst | 31 + Documentation/edac/scrub.rst | 76 + drivers/cxl/Kconfig | 71 + drivers/cxl/core/Makefile | 1 + drivers/cxl/core/core.h | 2 + drivers/cxl/core/edac.c | 2082 ++++++++++++++++++++++++++ drivers/cxl/core/features.c | 17 +- drivers/cxl/core/mbox.c | 11 +- drivers/cxl/core/memdev.c | 1 + drivers/cxl/core/region.c | 10 + drivers/cxl/cxl.h | 10 + drivers/cxl/cxlmem.h | 36 + drivers/cxl/mem.c | 4 + drivers/edac/mem_repair.c | 9 + include/linux/edac.h | 7 + 15 files changed, 2356 insertions(+), 12 deletions(-) create mode 100644 drivers/cxl/core/edac.c -- 2.43.0
