diff options
Diffstat (limited to 'arch/x86/platform/efi/quirks.c')
| -rw-r--r-- | arch/x86/platform/efi/quirks.c | 105 |
1 files changed, 92 insertions, 13 deletions
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c index 5b513ccffde4..95e77a667ba5 100644 --- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -8,7 +8,6 @@ #include <linux/efi.h> #include <linux/slab.h> #include <linux/memblock.h> -#include <linux/bootmem.h> #include <linux/acpi.h> #include <linux/dmi.h> @@ -16,6 +15,7 @@ #include <asm/efi.h> #include <asm/uv/uv.h> #include <asm/cpu_device_id.h> +#include <asm/reboot.h> #define EFI_MIN_RESERVE 5120 @@ -75,7 +75,7 @@ struct quark_security_header { u32 rsvd[2]; }; -static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 }; +static const efi_char16_t efi_dummy_name[] = L"DUMMY"; static bool efi_no_storage_paranoia; @@ -105,11 +105,11 @@ early_param("efi_no_storage_paranoia", setup_storage_paranoia); */ void efi_delete_dummy_variable(void) { - efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, - EFI_VARIABLE_NON_VOLATILE | - EFI_VARIABLE_BOOTSERVICE_ACCESS | - EFI_VARIABLE_RUNTIME_ACCESS, - 0, NULL); + efi.set_variable_nonblocking((efi_char16_t *)efi_dummy_name, + &EFI_DUMMY_GUID, + EFI_VARIABLE_NON_VOLATILE | + EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS, 0, NULL); } /* @@ -177,12 +177,13 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size, * that by attempting to use more space than is available. */ unsigned long dummy_size = remaining_size + 1024; - void *dummy = kzalloc(dummy_size, GFP_ATOMIC); + void *dummy = kzalloc(dummy_size, GFP_KERNEL); if (!dummy) return EFI_OUT_OF_RESOURCES; - status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, + status = efi.set_variable((efi_char16_t *)efi_dummy_name, + &EFI_DUMMY_GUID, EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS, @@ -247,7 +248,8 @@ void __init efi_arch_mem_reserve(phys_addr_t addr, u64 size) int num_entries; void *new; - if (efi_mem_desc_lookup(addr, &md)) { + if (efi_mem_desc_lookup(addr, &md) || + md.type != EFI_BOOT_SERVICES_DATA) { pr_err("Failed to lookup EFI memory descriptor for %pa\n", &addr); return; } @@ -330,7 +332,7 @@ void __init efi_reserve_boot_services(void) /* * Because the following memblock_reserve() is paired - * with free_bootmem_late() for this region in + * with memblock_free_late() for this region in * efi_free_boot_services(), we must be extremely * careful not to reserve, and subsequently free, * critical regions of memory (like the kernel image) or @@ -361,7 +363,7 @@ void __init efi_reserve_boot_services(void) * doesn't make sense as far as the firmware is * concerned, but it does provide us with a way to tag * those regions that must not be paired with - * free_bootmem_late(). + * memblock_free_late(). */ md->attribute |= EFI_MEMORY_RUNTIME; } @@ -411,7 +413,7 @@ void __init efi_free_boot_services(void) size -= rm_size; } - free_bootmem_late(start, size); + memblock_free_late(start, size); } if (!num_entries) @@ -652,3 +654,80 @@ int efi_capsule_setup_info(struct capsule_info *cap_info, void *kbuff, } #endif + +/* + * If any access by any efi runtime service causes a page fault, then, + * 1. If it's efi_reset_system(), reboot through BIOS. + * 2. If any other efi runtime service, then + * a. Return error status to the efi caller process. + * b. Disable EFI Runtime Services forever and + * c. Freeze efi_rts_wq and schedule new process. + * + * @return: Returns, if the page fault is not handled. This function + * will never return if the page fault is handled successfully. + */ +void efi_recover_from_page_fault(unsigned long phys_addr) +{ + if (!IS_ENABLED(CONFIG_X86_64)) + return; + + /* + * Make sure that an efi runtime service caused the page fault. + * "efi_mm" cannot be used to check if the page fault had occurred + * in the firmware context because efi=old_map doesn't use efi_pgd. + */ + if (efi_rts_work.efi_rts_id == NONE) + return; + + /* + * Address range 0x0000 - 0x0fff is always mapped in the efi_pgd, so + * page faulting on these addresses isn't expected. + */ + if (phys_addr >= 0x0000 && phys_addr <= 0x0fff) + return; + + /* + * Print stack trace as it might be useful to know which EFI Runtime + * Service is buggy. + */ + WARN(1, FW_BUG "Page fault caused by firmware at PA: 0x%lx\n", + phys_addr); + + /* + * Buggy efi_reset_system() is handled differently from other EFI + * Runtime Services as it doesn't use efi_rts_wq. Although, + * native_machine_emergency_restart() says that machine_real_restart() + * could fail, it's better not to compilcate this fault handler + * because this case occurs *very* rarely and hence could be improved + * on a need by basis. + */ + if (efi_rts_work.efi_rts_id == RESET_SYSTEM) { + pr_info("efi_reset_system() buggy! Reboot through BIOS\n"); + machine_real_restart(MRR_BIOS); + return; + } + + /* + * Before calling EFI Runtime Service, the kernel has switched the + * calling process to efi_mm. Hence, switch back to task_mm. + */ + arch_efi_call_virt_teardown(); + + /* Signal error status to the efi caller process */ + efi_rts_work.status = EFI_ABORTED; + complete(&efi_rts_work.efi_rts_comp); + + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); + pr_info("Froze efi_rts_wq and disabled EFI Runtime Services\n"); + + /* + * Call schedule() in an infinite loop, so that any spurious wake ups + * will never run efi_rts_wq again. + */ + for (;;) { + set_current_state(TASK_IDLE); + schedule(); + } + + return; +} |