As a first step to removing the awkward 'struct efi_scratch' definition
that conveniently combines the storage of the mixed mode stack pointer
with the MM pointer variable that records the task's MM pointer while it
is being replaced with the EFI MM one, move the mixed mode stack pointer
into a separate variable.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
arch/x86/include/asm/efi.h | 3 +--
arch/x86/platform/efi/efi_64.c | 2 +-
arch/x86/platform/efi/efi_thunk_64.S | 6 +++++-
3 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index c98f78330b09..5e37e6d63c63 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -12,6 +12,7 @@
#include <linux/pgtable.h>
extern unsigned long efi_fw_vendor, efi_config_table;
+extern unsigned long efi_mixed_mode_stack_pa;
/*
* We map the EFI regions needed for runtime services non-contiguously,
@@ -96,11 +97,9 @@ extern asmlinkage u64 __efi_call(void *fp, ...);
/*
* struct efi_scratch - Scratch space used while switching to/from efi_mm
- * @phys_stack: stack used during EFI Mixed Mode
* @prev_mm: store/restore stolen mm_struct while switching to/from efi_mm
*/
struct efi_scratch {
- u64 phys_stack;
struct mm_struct *prev_mm;
} __packed;
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index e1e8d4e3a213..1d904181e6a1 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -256,7 +256,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
return 1;
}
- efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */
+ efi_mixed_mode_stack_pa = page_to_phys(page + 1); /* stack grows down */
npages = (_etext - _text) >> PAGE_SHIFT;
text = __pa(_text);
diff --git a/arch/x86/platform/efi/efi_thunk_64.S b/arch/x86/platform/efi/efi_thunk_64.S
index 26f0da238c1c..fd3dd1708eba 100644
--- a/arch/x86/platform/efi/efi_thunk_64.S
+++ b/arch/x86/platform/efi/efi_thunk_64.S
@@ -33,7 +33,7 @@ SYM_CODE_START(__efi64_thunk)
* Switch to 1:1 mapped 32-bit stack pointer.
*/
movq %rsp, %rax
- movq efi_scratch(%rip), %rsp
+ movq efi_mixed_mode_stack_pa(%rip), %rsp
push %rax
/*
@@ -70,3 +70,7 @@ SYM_CODE_START(__efi64_thunk)
pushl %ebp
lret
SYM_CODE_END(__efi64_thunk)
+
+ .bss
+ .balign 8
+SYM_DATA(efi_mixed_mode_stack_pa, .quad 0)
--
2.17.1
