Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx> writes: > 在 2022/3/18 AM12:57, Luck, Tony 写道: >>> - rc = apei_exec_run(&trigger_ctx, ACPI_EINJ_TRIGGER_ERROR); >>> + ptr = kmap(pfn_to_page(pfn)); >>> + tmp = *(ptr + (param1 & ~ PAGE_MASK)); >> >> That hack works when the trigger action is just trying to access the injected >> location. But on Intel platforms the trigger "kicks" the patrol scrubber in the >> memory controller to access the address. So the error is triggered not by >> an access from the core, but by internal memory controller access. >> >> This results in a different error signature (for an uncorrected error injection >> it will be a UCNA or SRAO in Intel acronym-speak). > > As far as I know, APEI only defines five injection instructions, ACPI_EINJ_READ_REGISTER, > ACPI_EINJ_READ_REGISTER_VALUE, ACPI_EINJ_WRITE_REGISTER, ACPI_EINJ_WRITE_REGISTER_VALUE and > ACPI_EINJ_NOOP. ACPI_EINJ_TRIGGER_ERROR action should run one of them, I don't see > any of them will kick the patrol scrubber. For example, trigger with ACPI_EINJ_READ_REGISTER: > > apei_exec_run(&trigger_ctx, ACPI_EINJ_TRIGGER_ERROR) > __apei_exec_run // ins=0 > => apei_exec_read_register > => apei_read > => acpi_os_read_memory > => acpi_map_vaddr_lookup /* lookup VA of PA from acpi_ioremap */ > => acpi_os_ioremap > => acpi_os_read_iomem > => *(u32 *) value = readl(virt_addr); > > As we can see, the error is triggered by access from the core. However, the physical > address can NOT be mapped by acpi_os_ioremap. > > If I missed anything, please let me know. Thank you very much. As the name suggested, ACPI_EINJ_READ/WRITE_REGISTER are used to read/write device registers via iomem. They aren't used to read/write normal physical memory. If that's needed, you can try some other method I guess. If you write a device register, the device can kick the patrol scrubber for you. This device behavior needs not to be defined in APEI spec. Best Regards, Huang, Ying > Best Regards, > Shuai
