diff options
Diffstat (limited to 'arch/x86/platform/efi')
| -rw-r--r-- | arch/x86/platform/efi/early_printk.c | 8 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi.c | 3 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi_64.c | 12 | ||||
| -rw-r--r-- | arch/x86/platform/efi/quirks.c | 85 |
4 files changed, 93 insertions, 15 deletions
diff --git a/arch/x86/platform/efi/early_printk.c b/arch/x86/platform/efi/early_printk.c index 5fdacb322ceb..7476b3b097e1 100644 --- a/arch/x86/platform/efi/early_printk.c +++ b/arch/x86/platform/efi/early_printk.c @@ -26,12 +26,14 @@ static bool early_efi_keep; */ static __init int early_efi_map_fb(void) { - unsigned long base, size; + u64 base, size; if (!early_efi_keep) return 0; base = boot_params.screen_info.lfb_base; + if (boot_params.screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) + base |= (u64)boot_params.screen_info.ext_lfb_base << 32; size = boot_params.screen_info.lfb_size; efi_fb = ioremap(base, size); @@ -46,9 +48,11 @@ early_initcall(early_efi_map_fb); */ static __ref void *early_efi_map(unsigned long start, unsigned long len) { - unsigned long base; + u64 base; base = boot_params.screen_info.lfb_base; + if (boot_params.screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) + base |= (u64)boot_params.screen_info.ext_lfb_base << 32; if (efi_fb) return (efi_fb + start); diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 9061babfbc83..7ae939e353cd 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -36,9 +36,8 @@ #include <linux/efi.h> #include <linux/efi-bgrt.h> #include <linux/export.h> -#include <linux/bootmem.h> -#include <linux/slab.h> #include <linux/memblock.h> +#include <linux/slab.h> #include <linux/spinlock.h> #include <linux/uaccess.h> #include <linux/time.h> diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index ee5d08f25ce4..cf0347f61b21 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -23,7 +23,7 @@ #include <linux/mm.h> #include <linux/types.h> #include <linux/spinlock.h> -#include <linux/bootmem.h> +#include <linux/memblock.h> #include <linux/ioport.h> #include <linux/mc146818rtc.h> #include <linux/efi.h> @@ -619,18 +619,16 @@ void __init efi_dump_pagetable(void) /* * Makes the calling thread switch to/from efi_mm context. Can be used - * for SetVirtualAddressMap() i.e. current->active_mm == init_mm as well - * as during efi runtime calls i.e current->active_mm == current_mm. - * We are not mm_dropping()/mm_grabbing() any mm, because we are not - * losing/creating any references. + * in a kernel thread and user context. Preemption needs to remain disabled + * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm + * can not change under us. + * It should be ensured that there are no concurent calls to this function. */ void efi_switch_mm(struct mm_struct *mm) { - task_lock(current); efi_scratch.prev_mm = current->active_mm; current->active_mm = mm; switch_mm(efi_scratch.prev_mm, mm, NULL); - task_unlock(current); } #ifdef CONFIG_EFI_MIXED diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c index 844d31cb8a0c..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 @@ -332,7 +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 @@ -363,7 +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; } @@ -413,7 +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) @@ -654,3 +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; +} |
