kernel/linux.git/drivers/acpi/acpi_extlog.c, branch linux-7.1.y

ACPI: extlog: Trace CPER CXL Protocol Error Section

2026-01-14T16:09:34+00:00

When Firmware First is enabled, BIOS handles errors first and then it makes them available to the kernel via the Common Platform Error Record (CPER) sections (UEFI 2.11 Appendix N.2.13). Linux parses the CPER sections via one of two similar paths, either ELOG or GHES. The errors managed by ELOG are signaled to the BIOS by the I/O Machine Check Architecture (I/O MCA). Currently, ELOG and GHES show some inconsistencies in how they report to userspace via trace events. Therefore, make the two mentioned paths act similarly by tracing the CPER CXL Protocol Error Section. Reviewed-by: Dave Jiang Reviewed-by: Jonathan Cameron Reviewed-by: Kuppuswamy Sathyanarayanan Signed-off-by: Fabio M. De Francesco Link: https://patch.msgid.link/20260114101543.85926-6-fabio.m.de.francesco@linux.intel.com Signed-off-by: Rafael J. Wysocki

ACPI: extlog: Trace CPER PCI Express Error Section

2026-01-14T16:09:34+00:00

I/O Machine Check Architecture events may signal failing PCIe components or links. The AER event contains details on what was happening on the wire when the error was signaled. Trace the CPER PCIe Error section (UEFI v2.11, Appendix N.2.7) reported by the I/O MCA. Reviewed-by: Dave Jiang Reviewed-by: Jonathan Cameron Signed-off-by: Fabio M. De Francesco Link: https://patch.msgid.link/20260114101543.85926-3-fabio.m.de.francesco@linux.intel.com Signed-off-by: Rafael J. Wysocki

ACPI: extlog: Trace CPER Non-standard Section Body

2026-01-14T16:09:34+00:00

ghes_do_proc() has a catch-all for unknown or unhandled CPER formats (UEFI v2.11 Appendix N 2.3), extlog_print() does not. This gap was noticed by a RAS test that injected CXL protocol errors which were notified to extlog_print() via the IOMCA (I/O Machine Check Architecture) mechanism. Bring parity to the extlog_print() path by including a similar log_non_standard_event(). Reviewed-by: Dan Williams Reviewed-by: Dave Jiang Reviewed-by: Jonathan Cameron Reviewed-by: Kuppuswamy Sathyanarayanan Reviewed-by: Qiuxu Zhuo Reviewed-by: Shuai Xue Signed-off-by: Fabio M. De Francesco Link: https://patch.msgid.link/20260114101543.85926-2-fabio.m.de.francesco@linux.intel.com Signed-off-by: Rafael J. Wysocki

x86/msr: Add explicit includes of

2025-05-02T08:23:47+00:00

For historic reasons there are some TSC-related functions in the header, even though there's an header. To facilitate the relocation of rdtsc{,_ordered}() from to and to eventually eliminate the inclusion of in , add an explicit dependency to the source files that reference definitions from . [ mingo: Clarified the changelog. ] Signed-off-by: Xin Li (Intel) Signed-off-by: Ingo Molnar Acked-by: Dave Hansen Acked-by: Peter Zijlstra (Intel) Acked-by: Ilpo Järvinen Cc: Andy Lutomirski Cc: Brian Gerst Cc: Juergen Gross Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Kees Cook Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Thomas Gleixner Cc: Josh Poimboeuf Cc: Uros Bizjak Link: https://lore.kernel.org/r/20250501054241.1245648-1-xin@zytor.com

x86/msr: Rename 'rdmsrl_safe()' to 'rdmsrq_safe()'

2025-04-10T09:58:38+00:00

Suggested-by: "H. Peter Anvin" Signed-off-by: Ingo Molnar Acked-by: Peter Zijlstra (Intel) Cc: Juergen Gross Cc: Dave Hansen Cc: Xin Li Cc: Linus Torvalds

mm/early_ioremap: add null pointer checks to prevent NULL-pointer dereference

2025-01-14T06:40:59+00:00

The early_ioremap interface can fail and return NULL in certain cases. To prevent NULL-pointer dereference crashes, fixed issues in the acpi_extlog and copy_early_mem interfaces, improving robustness when handling early memory. Link: https://lkml.kernel.org/r/20241212101004.1544070-1-guoweikang.kernel@gmail.com Signed-off-by: Guo Weikang Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Baoquan He Cc: Borislav Petkov (AMD) Cc: Dave Hansen Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Ingo Molnar Cc: Jason A. Donenfeld Cc: Julian Stecklina Cc: Kevin Loughlin Cc: Len Brown Cc: Rafael J. Wysocki Cc: "Rafael J. Wysocki" Cc: Thomas Gleixner Cc: Xin Li (Intel) Signed-off-by: Andrew Morton

ACPI: extlog: Clear Extended Error Log status when RAS_CEC handled the error

2023-12-13T12:50:00+00:00

When both CONFIG_RAS_CEC and CONFIG_ACPI_EXTLOG are enabled, Linux does not clear the status word of the BIOS supplied error record for corrected errors. This may prevent logging of subsequent uncorrected errors. Fix by clearing the status. Fixes: 23ba710a0864 ("x86/mce: Fix all mce notifiers to update the mce->kflags bitmask") Reported-by: Erwin Tsaur Signed-off-by: Tony Luck Signed-off-by: Rafael J. Wysocki

ACPI: extlog: fix NULL pointer dereference check

2023-12-06T20:21:09+00:00

The gcc plugin -fanalyzer [1] tries to detect various patterns of incorrect behaviour. The tool reports: drivers/acpi/acpi_extlog.c: In function ‘extlog_exit’: drivers/acpi/acpi_extlog.c:307:12: warning: check of ‘extlog_l1_addr’ for NULL after already dereferencing it [-Wanalyzer-deref-before-check] | | 306 | ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; | | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~ | | | | | (1) pointer ‘extlog_l1_addr’ is dereferenced here | 307 | if (extlog_l1_addr) | | ~ | | | | | (2) pointer ‘extlog_l1_addr’ is checked for NULL here but it was already dereferenced at (1) | Fix the NULL pointer dereference check in extlog_exit(). Link: https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Static-Analyzer-Options.html # [1] Signed-off-by: Prarit Bhargava Signed-off-by: Rafael J. Wysocki

ACPI: extlog: Fix finding the generic error data for v3 structure

2023-08-17T17:44:22+00:00

Fix by using acpi_hest_get_payload() to find out the correct generic error data for v3 structure. The revision v300 generic error data is different from the old one, so for compatibility with old and new version, change to a new interface to locate the right memory error section that was defined in CPER. Signed-off-by: Xiaochun Lee Reviewed-by: Tony Luck Signed-off-by: Rafael J. Wysocki

ACPI: extlog: Handle multiple records

2022-10-13T18:43:10+00:00

If there is no user space consumer of extlog_mem trace records, then Linux properly handles multiple error records in an ELOG block extlog_print() print_extlog_rcd() __print_extlog_rcd() cper_estatus_print() apei_estatus_for_each_section() But the other code path hard codes looking for a single record to output a trace record. Fix by using the same apei_estatus_for_each_section() iterator to step over all records. Fixes: 2dfb7d51a61d ("trace, RAS: Add eMCA trace event interface") Signed-off-by: Tony Luck Signed-off-by: Rafael J. Wysocki