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-rw-r--r--arch/x86/include/asm/efi.h6
-rw-r--r--arch/x86/platform/efi/efi.c19
-rw-r--r--arch/x86/platform/efi/efi_64.c73
-rw-r--r--arch/x86/platform/efi/efi_thunk_64.S121
4 files changed, 71 insertions, 148 deletions
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index cb08035b89a0..e7e9c6e057f9 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -164,12 +164,6 @@ extern void parse_efi_setup(u64 phys_addr, u32 data_len);
extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
extern void efi_thunk_runtime_setup(void);
-extern efi_status_t efi_thunk_set_virtual_address_map(
- void *phys_set_virtual_address_map,
- unsigned long memory_map_size,
- unsigned long descriptor_size,
- u32 descriptor_version,
- efi_memory_desc_t *virtual_map);
efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
unsigned long descriptor_size,
u32 descriptor_version,
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 50f8123e658a..e4d3afac7be3 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -1015,21 +1015,10 @@ static void __init __efi_enter_virtual_mode(void)
efi_sync_low_kernel_mappings();
- if (!efi_is_mixed()) {
- status = efi_set_virtual_address_map(
- efi.memmap.desc_size * count,
- efi.memmap.desc_size,
- efi.memmap.desc_version,
- (efi_memory_desc_t *)pa);
- } else {
- status = efi_thunk_set_virtual_address_map(
- efi_phys.set_virtual_address_map,
- efi.memmap.desc_size * count,
- efi.memmap.desc_size,
- efi.memmap.desc_version,
- (efi_memory_desc_t *)pa);
- }
-
+ status = efi_set_virtual_address_map(efi.memmap.desc_size * count,
+ efi.memmap.desc_size,
+ efi.memmap.desc_version,
+ (efi_memory_desc_t *)pa);
if (status != EFI_SUCCESS) {
pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
status);
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 03565dad0c4b..910e9ec03b09 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -626,61 +626,74 @@ void efi_switch_mm(struct mm_struct *mm)
switch_mm(efi_scratch.prev_mm, mm, NULL);
}
-#ifdef CONFIG_EFI_MIXED
static DEFINE_SPINLOCK(efi_runtime_lock);
-#define runtime_service32(func) \
-({ \
- u32 table = (u32)(unsigned long)efi.systab; \
- u32 *rt, *___f; \
- \
- rt = (u32 *)(table + offsetof(efi_system_table_32_t, runtime)); \
- ___f = (u32 *)(*rt + offsetof(efi_runtime_services_32_t, func)); \
- *___f; \
+/*
+ * DS and ES contain user values. We need to save them.
+ * The 32-bit EFI code needs a valid DS, ES, and SS. There's no
+ * need to save the old SS: __KERNEL_DS is always acceptable.
+ */
+#define __efi_thunk(func, ...) \
+({ \
+ efi_runtime_services_32_t *__rt; \
+ unsigned short __ds, __es; \
+ efi_status_t ____s; \
+ \
+ __rt = (void *)(unsigned long)efi.systab->mixed_mode.runtime; \
+ \
+ savesegment(ds, __ds); \
+ savesegment(es, __es); \
+ \
+ loadsegment(ss, __KERNEL_DS); \
+ loadsegment(ds, __KERNEL_DS); \
+ loadsegment(es, __KERNEL_DS); \
+ \
+ ____s = efi64_thunk(__rt->func, __VA_ARGS__); \
+ \
+ loadsegment(ds, __ds); \
+ loadsegment(es, __es); \
+ \
+ ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32; \
+ ____s; \
})
/*
* Switch to the EFI page tables early so that we can access the 1:1
* runtime services mappings which are not mapped in any other page
- * tables. This function must be called before runtime_service32().
+ * tables.
*
* Also, disable interrupts because the IDT points to 64-bit handlers,
* which aren't going to function correctly when we switch to 32-bit.
*/
-#define efi_thunk(f, ...) \
+#define efi_thunk(func...) \
({ \
efi_status_t __s; \
- u32 __func; \
\
arch_efi_call_virt_setup(); \
\
- __func = runtime_service32(f); \
- __s = efi64_thunk(__func, __VA_ARGS__); \
+ __s = __efi_thunk(func); \
\
arch_efi_call_virt_teardown(); \
\
__s; \
})
-efi_status_t efi_thunk_set_virtual_address_map(
- void *phys_set_virtual_address_map,
- unsigned long memory_map_size,
- unsigned long descriptor_size,
- u32 descriptor_version,
- efi_memory_desc_t *virtual_map)
+static efi_status_t __init
+efi_thunk_set_virtual_address_map(unsigned long memory_map_size,
+ unsigned long descriptor_size,
+ u32 descriptor_version,
+ efi_memory_desc_t *virtual_map)
{
efi_status_t status;
unsigned long flags;
- u32 func;
efi_sync_low_kernel_mappings();
local_irq_save(flags);
efi_switch_mm(&efi_mm);
- func = (u32)(unsigned long)phys_set_virtual_address_map;
- status = efi64_thunk(func, memory_map_size, descriptor_size,
- descriptor_version, virtual_map);
+ status = __efi_thunk(set_virtual_address_map, memory_map_size,
+ descriptor_size, descriptor_version, virtual_map);
efi_switch_mm(efi_scratch.prev_mm);
local_irq_restore(flags);
@@ -983,8 +996,11 @@ efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules,
return EFI_UNSUPPORTED;
}
-void efi_thunk_runtime_setup(void)
+void __init efi_thunk_runtime_setup(void)
{
+ if (!IS_ENABLED(CONFIG_EFI_MIXED))
+ return;
+
efi.get_time = efi_thunk_get_time;
efi.set_time = efi_thunk_set_time;
efi.get_wakeup_time = efi_thunk_get_wakeup_time;
@@ -1000,7 +1016,6 @@ void efi_thunk_runtime_setup(void)
efi.update_capsule = efi_thunk_update_capsule;
efi.query_capsule_caps = efi_thunk_query_capsule_caps;
}
-#endif /* CONFIG_EFI_MIXED */
efi_status_t __init efi_set_virtual_address_map(unsigned long memory_map_size,
unsigned long descriptor_size,
@@ -1011,6 +1026,12 @@ efi_status_t __init efi_set_virtual_address_map(unsigned long memory_map_size,
unsigned long flags;
pgd_t *save_pgd = NULL;
+ if (efi_is_mixed())
+ return efi_thunk_set_virtual_address_map(memory_map_size,
+ descriptor_size,
+ descriptor_version,
+ virtual_map);
+
if (efi_enabled(EFI_OLD_MEMMAP)) {
save_pgd = efi_old_memmap_phys_prolog();
if (!save_pgd)
diff --git a/arch/x86/platform/efi/efi_thunk_64.S b/arch/x86/platform/efi/efi_thunk_64.S
index 3189f1394701..162b35729633 100644
--- a/arch/x86/platform/efi/efi_thunk_64.S
+++ b/arch/x86/platform/efi/efi_thunk_64.S
@@ -25,15 +25,16 @@
.text
.code64
-SYM_FUNC_START(efi64_thunk)
+SYM_CODE_START(efi64_thunk)
push %rbp
push %rbx
/*
* Switch to 1:1 mapped 32-bit stack pointer.
*/
- movq %rsp, efi_saved_sp(%rip)
+ movq %rsp, %rax
movq efi_scratch(%rip), %rsp
+ push %rax
/*
* Calculate the physical address of the kernel text.
@@ -41,113 +42,31 @@ SYM_FUNC_START(efi64_thunk)
movq $__START_KERNEL_map, %rax
subq phys_base(%rip), %rax
- /*
- * Push some physical addresses onto the stack. This is easier
- * to do now in a code64 section while the assembler can address
- * 64-bit values. Note that all the addresses on the stack are
- * 32-bit.
- */
- subq $16, %rsp
- leaq efi_exit32(%rip), %rbx
- subq %rax, %rbx
- movl %ebx, 8(%rsp)
-
- leaq __efi64_thunk(%rip), %rbx
+ leaq 1f(%rip), %rbp
+ leaq 2f(%rip), %rbx
+ subq %rax, %rbp
subq %rax, %rbx
- call *%rbx
-
- movq efi_saved_sp(%rip), %rsp
- pop %rbx
- pop %rbp
- retq
-SYM_FUNC_END(efi64_thunk)
-/*
- * We run this function from the 1:1 mapping.
- *
- * This function must be invoked with a 1:1 mapped stack.
- */
-SYM_FUNC_START_LOCAL(__efi64_thunk)
- movl %ds, %eax
- push %rax
- movl %es, %eax
- push %rax
- movl %ss, %eax
- push %rax
-
- subq $32, %rsp
- movl %esi, 0x0(%rsp)
- movl %edx, 0x4(%rsp)
- movl %ecx, 0x8(%rsp)
- movq %r8, %rsi
- movl %esi, 0xc(%rsp)
- movq %r9, %rsi
- movl %esi, 0x10(%rsp)
-
- leaq 1f(%rip), %rbx
- movq %rbx, func_rt_ptr(%rip)
+ subq $28, %rsp
+ movl %ebx, 0x0(%rsp) /* return address */
+ movl %esi, 0x4(%rsp)
+ movl %edx, 0x8(%rsp)
+ movl %ecx, 0xc(%rsp)
+ movl %r8d, 0x10(%rsp)
+ movl %r9d, 0x14(%rsp)
/* Switch to 32-bit descriptor */
pushq $__KERNEL32_CS
- leaq efi_enter32(%rip), %rax
- pushq %rax
+ pushq %rdi /* EFI runtime service address */
lretq
-1: addq $32, %rsp
-
+1: movq 24(%rsp), %rsp
pop %rbx
- movl %ebx, %ss
- pop %rbx
- movl %ebx, %es
- pop %rbx
- movl %ebx, %ds
-
- /*
- * Convert 32-bit status code into 64-bit.
- */
- test %rax, %rax
- jz 1f
- movl %eax, %ecx
- andl $0x0fffffff, %ecx
- andl $0xf0000000, %eax
- shl $32, %rax
- or %rcx, %rax
-1:
- ret
-SYM_FUNC_END(__efi64_thunk)
-
-SYM_FUNC_START_LOCAL(efi_exit32)
- movq func_rt_ptr(%rip), %rax
- push %rax
- mov %rdi, %rax
- ret
-SYM_FUNC_END(efi_exit32)
+ pop %rbp
+ retq
.code32
-/*
- * EFI service pointer must be in %edi.
- *
- * The stack should represent the 32-bit calling convention.
- */
-SYM_FUNC_START_LOCAL(efi_enter32)
- movl $__KERNEL_DS, %eax
- movl %eax, %ds
- movl %eax, %es
- movl %eax, %ss
-
- call *%edi
-
- /* We must preserve return value */
- movl %eax, %edi
-
- movl 72(%esp), %eax
- pushl $__KERNEL_CS
- pushl %eax
-
+2: pushl $__KERNEL_CS
+ pushl %ebp
lret
-SYM_FUNC_END(efi_enter32)
-
- .data
- .balign 8
-func_rt_ptr: .quad 0
-efi_saved_sp: .quad 0
+SYM_CODE_END(efi64_thunk)