blaster4385/linux-IllusionX/arch/x86/kernel/cpu/mce/core.c, branch v6.13

x86/MCE/AMD: Add support for new MCA_SYND{1,2} registers

2024-10-31T09:36:07Z

Starting with Zen4, AMD's Scalable MCA systems incorporate two new registers: MCA_SYND1 and MCA_SYND2. These registers will include supplemental error information in addition to the existing MCA_SYND register. The data within these registers is considered valid if MCA_STATUS[SyndV] is set. Userspace error decoding tools like rasdaemon gather related hardware error information through the tracepoints. Therefore, export these two registers through the mce_record tracepoint so that tools like rasdaemon can parse them and output the supplemental error information like FRU text contained in them. [ bp: Massage. ] Signed-off-by: Yazen Ghannam Signed-off-by: Avadhut Naik Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Qiuxu Zhuo Link: https://lore.kernel.org/r/20241022194158.110073-4-avadhut.naik@amd.com

x86/mce: Add wrapper for struct mce to export vendor specific info

2024-10-30T16:18:59Z

Currently, exporting new additional machine check error information involves adding new fields for the same at the end of the struct mce. This additional information can then be consumed through mcelog or tracepoint. However, as new MSRs are being added (and will be added in the future) by CPU vendors on their newer CPUs with additional machine check error information to be exported, the size of struct mce will balloon on some CPUs, unnecessarily, since those fields are vendor-specific. Moreover, different CPU vendors may export the additional information in varying sizes. The problem particularly intensifies since struct mce is exposed to userspace as part of UAPI. It's bloating through vendor-specific data should be avoided to limit the information being sent out to userspace. Add a new structure mce_hw_err to wrap the existing struct mce. The same will prevent its ballooning since vendor-specifc data, if any, can now be exported through a union within the wrapper structure and through __dynamic_array in mce_record tracepoint. Furthermore, new internal kernel fields can be added to the wrapper struct without impacting the user space API. [ bp: Restore reverse x-mas tree order of function vars declarations. ] Suggested-by: Borislav Petkov (AMD) Signed-off-by: Avadhut Naik Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Qiuxu Zhuo Link: https://lore.kernel.org/r/20241022194158.110073-2-avadhut.naik@amd.com

x86/mce: Define mce_prep_record() helpers for common and per-CPU fields

2024-08-01T16:20:25Z

Generally, MCA information for an error is gathered on the CPU that reported the error. In this case, CPU-specific information from the running CPU will be correct. However, this will be incorrect if the MCA information is gathered while running on a CPU that didn't report the error. One example is creating an MCA record using mce_prep_record() for errors reported from ACPI. Split mce_prep_record() so that there is a helper function to gather common, i.e. not CPU-specific, information and another helper for CPU-specific information. Leave mce_prep_record() defined as-is for the common case when running on the reporting CPU. Get MCG_CAP in the global helper even though the register is per-CPU. This value is not already cached per-CPU like other values. And it does not assist with any per-CPU decoding or handling. Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Nikolay Borisov Link: https://lore.kernel.org/r/20240730182958.4117158-3-yazen.ghannam@amd.com Signed-off-by: Borislav Petkov (AMD)

x86/mce: Rename mce_setup() to mce_prep_record()

2024-08-01T16:20:24Z

There is no MCE "setup" done in mce_setup(). Rather, this function initializes and prepares an MCE record. Rename the function to highlight what it does. No functional change is intended. Suggested-by: Borislav Petkov Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Nikolay Borisov Link: https://lore.kernel.org/r/20240730182958.4117158-2-yazen.ghannam@amd.com Signed-off-by: Borislav Petkov (AMD)

x86/mce: Remove unused variable and return value in machine_check_poll()

2024-05-27T08:49:25Z

The recent CMCI storm handling rework removed the last case that checks the return value of machine_check_poll(). Therefore the "error_seen" variable is no longer used, so remove it. Fixes: 3ed57b41a412 ("x86/mce: Remove old CMCI storm mitigation code") Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20240523155641.2805411-3-yazen.ghannam@amd.com Signed-off-by: Borislav Petkov (AMD)

x86/mce: Switch to new Intel CPU model defines

2024-04-29T08:31:23Z

New CPU #defines encode vendor and family as well as model. [ bp: Squash *three* mce patches into one, fold in fix: https://lore.kernel.org/r/20240429022051.63360-1-tony.luck@intel.com ] Signed-off-by: Tony Luck Signed-off-by: Dave Hansen Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/all/20240424181511.41772-1-tony.luck%40intel.com

x86/mce: Implement recovery for errors in TDX/SEAM non-root mode

2024-04-09T07:30:36Z

Machine check SMIs (MSMI) signaled during SEAM operation (typically inside TDX guests), on a system with Intel eMCA enabled, might eventually be reported to the kernel #MC handler with the saved RIP on the stack pointing to the instruction in kernel code after the SEAMCALL instruction that entered the SEAM operation. Linux currently says that is a fatal error and shuts down. There is a new bit in IA32_MCG_STATUS that, when set to 1, indicates that the machine check didn't originally occur at that saved RIP, but during SEAM non-root operation. Add new entries to the severity table to detect this for both data load and instruction fetch that set the severity to "AR" (action required). Increase the width of the mcgmask/mcgres fields in "struct severity" from unsigned char to unsigned short since the new bit is in position 12. Action required for these errors is just mark the page as poisoned and return from the machine check handler. HW ABI notes: ============= The SEAM_NR bit in IA32_MCG_STATUS hasn't yet made it into the Intel Software Developers' Manual. But it is described in section 16.5.2 of "Intel(R) Trust Domain Extensions (Intel(R) TDX) Module Base Architecture Specification" downloadable from: https://cdrdv2.intel.com/v1/dl/getContent/733575 Backport notes: =============== Little value in backporting this patch to stable or LTS kernels as this is only relevant with support for TDX, which I assume won't be backported. But for anyone taking this to v6.1 or older, you also need commit: a51cbd0d86d3 ("x86/mce: Use severity table to handle uncorrected errors in kernel") Signed-off-by: Tony Luck Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20240408180944.44638-1-tony.luck@intel.com

x86/mce: Make sure to grab mce_sysfs_mutex in set_bank()

2024-04-04T15:25:15Z

Modifying a MCA bank's MCA_CTL bits which control which error types to be reported is done over /sys/devices/system/machinecheck/ ├── machinecheck0 │ ├── bank0 │ ├── bank1 │ ├── bank10 │ ├── bank11 ... sysfs nodes by writing the new bit mask of events to enable. When the write is accepted, the kernel deletes all current timers and reinits all banks. Doing that in parallel can lead to initializing a timer which is already armed and in the timer wheel, i.e., in use already: ODEBUG: init active (active state 0) object: ffff888063a28000 object type: timer_list hint: mce_timer_fn+0x0/0x240 arch/x86/kernel/cpu/mce/core.c:2642 WARNING: CPU: 0 PID: 8120 at lib/debugobjects.c:514 debug_print_object+0x1a0/0x2a0 lib/debugobjects.c:514 Fix that by grabbing the sysfs mutex as the rest of the MCA sysfs code does. Reported by: Yue Sun Reported by: xingwei lee Signed-off-by: Borislav Petkov (AMD) Cc: Link: https://lore.kernel.org/r/CAEkJfYNiENwQY8yV1LYJ9LjJs%2Bx_-PqMv98gKig55=2vbzffRw@mail.gmail.com

Merge tag 'ras_core_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2024-03-12T00:22:57Z

Pull RAS fixlet from Borislav Petkov: - Constify yet another static struct bus_type instance now that the driver core can handle that * tag 'ras_core_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Make mce_subsys const

x86/mce: Make mce_subsys const

2024-02-05T09:26:51Z

Now that the driver core can properly handle constant struct bus_type, make mce_subsys a constant structure. Suggested-by: Greg Kroah-Hartman Signed-off-by: Ricardo B. Marliere Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20240204-bus_cleanup-x86-v1-1-4e7171be88e8@marliere.net