Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-29 23:51:37 +00:00
Code Issues Packages Projects Releases Wiki Activity

efi: x86: move mixed mode stack PA variable out of 'efi_scratch'

Browse Source 
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@kernel.org>
This commit is contained in:
Ard Biesheuvel 2021-01-19 15:16:27 +01:00
parent 3820749ddc
commit 3e1e00c00e
3 changed files with 7 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/x86/include/asm/efi.h
View File

@ -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;

2
arch/x86/platform/efi/efi_64.c
View File

@ -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);

6
arch/x86/platform/efi/efi_thunk_64.S
View File

@ -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)