diff options
Diffstat (limited to 'arch/arm64/kernel/efi.c')
| -rw-r--r-- | arch/arm64/kernel/efi.c | 45 |
1 files changed, 34 insertions, 11 deletions
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index ee53f2a0aa03..fab05de2e12d 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -9,7 +9,6 @@ #include <linux/efi.h> #include <linux/init.h> -#include <linux/percpu.h> #include <asm/efi.h> @@ -146,16 +145,11 @@ asmlinkage efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f) return s; } -asmlinkage DEFINE_PER_CPU(u64, __efi_rt_asm_recover_sp); +DEFINE_SPINLOCK(efi_rt_lock); -asmlinkage efi_status_t __efi_rt_asm_recover(void); +asmlinkage u64 *efi_rt_stack_top __ro_after_init; -asmlinkage efi_status_t efi_handle_runtime_exception(const char *f) -{ - pr_err(FW_BUG "Synchronous exception occurred in EFI runtime service %s()\n", f); - clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); - return EFI_ABORTED; -} +asmlinkage efi_status_t __efi_rt_asm_recover(void); bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg) { @@ -165,8 +159,37 @@ bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg) pr_err(FW_BUG "Unable to handle %s in EFI runtime service\n", msg); add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); - dump_stack(); + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); + + regs->regs[0] = EFI_ABORTED; + regs->regs[30] = efi_rt_stack_top[-1]; + regs->pc = (u64)__efi_rt_asm_recover; + + if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) + regs->regs[18] = efi_rt_stack_top[-2]; - regs->pc = (u64)__efi_rt_asm_recover; return true; } + +/* EFI requires 8 KiB of stack space for runtime services */ +static_assert(THREAD_SIZE >= SZ_8K); + +static int __init arm64_efi_rt_init(void) +{ + void *p; + + if (!efi_enabled(EFI_RUNTIME_SERVICES)) + return 0; + + p = __vmalloc_node(THREAD_SIZE, THREAD_ALIGN, GFP_KERNEL, + NUMA_NO_NODE, &&l); +l: if (!p) { + pr_warn("Failed to allocate EFI runtime stack\n"); + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); + return -ENOMEM; + } + + efi_rt_stack_top = p + THREAD_SIZE; + return 0; +} +core_initcall(arm64_efi_rt_init); |