mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-25 03:50:53 +07:00
cc456c4e7c
The git commite7a5cd063c7b4c58417f674821d63f5eb6747e37
("x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path
is not needed.") assumes that for the hibernate path the booting
kernel and the resuming kernel MUST be the same. That is certainly
the case for a 32-bit kernel (see check_image_kernel and
CONFIG_ARCH_HIBERNATION_HEADER config option).
However for 64-bit kernels it is OK to have a different kernel
version (and size of the image) of the booting and resuming kernels.
Hence the above mentioned git commit introduces an regression.
This patch fixes it by introducing a 'struct desc_ptr gdt_desc'
back in the 'struct saved_context'. However instead of having in the
'save_processor_state' and 'restore_processor_state' the
store/load_gdt calls, we are only saving the GDT in the
save_processor_state.
For the restore path the lgdt operation is done in
hibernate_asm_[32|64].S in the 'restore_registers' path.
The apt reader of this description will recognize that only 64-bit
kernels need this treatment, not 32-bit. This patch adds the logic
in the 32-bit path to be more similar to 64-bit so that in the future
the unification process can take advantage of this.
[ hpa: this also reverts an inadvertent on-disk format change ]
Suggested-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1367459610-9656-2-git-send-email-konrad.wilk@oracle.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
85 lines
1.7 KiB
ArmAsm
85 lines
1.7 KiB
ArmAsm
/*
|
|
* This may not use any stack, nor any variable that is not "NoSave":
|
|
*
|
|
* Its rewriting one kernel image with another. What is stack in "old"
|
|
* image could very well be data page in "new" image, and overwriting
|
|
* your own stack under you is bad idea.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/segment.h>
|
|
#include <asm/page_types.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/processor-flags.h>
|
|
|
|
.text
|
|
|
|
ENTRY(swsusp_arch_suspend)
|
|
movl %esp, saved_context_esp
|
|
movl %ebx, saved_context_ebx
|
|
movl %ebp, saved_context_ebp
|
|
movl %esi, saved_context_esi
|
|
movl %edi, saved_context_edi
|
|
pushfl
|
|
popl saved_context_eflags
|
|
|
|
call swsusp_save
|
|
ret
|
|
|
|
ENTRY(restore_image)
|
|
movl mmu_cr4_features, %ecx
|
|
movl resume_pg_dir, %eax
|
|
subl $__PAGE_OFFSET, %eax
|
|
movl %eax, %cr3
|
|
|
|
jecxz 1f # cr4 Pentium and higher, skip if zero
|
|
andl $~(X86_CR4_PGE), %ecx
|
|
movl %ecx, %cr4; # turn off PGE
|
|
movl %cr3, %eax; # flush TLB
|
|
movl %eax, %cr3
|
|
1:
|
|
movl restore_pblist, %edx
|
|
.p2align 4,,7
|
|
|
|
copy_loop:
|
|
testl %edx, %edx
|
|
jz done
|
|
|
|
movl pbe_address(%edx), %esi
|
|
movl pbe_orig_address(%edx), %edi
|
|
|
|
movl $1024, %ecx
|
|
rep
|
|
movsl
|
|
|
|
movl pbe_next(%edx), %edx
|
|
jmp copy_loop
|
|
.p2align 4,,7
|
|
|
|
done:
|
|
/* go back to the original page tables */
|
|
movl $swapper_pg_dir, %eax
|
|
subl $__PAGE_OFFSET, %eax
|
|
movl %eax, %cr3
|
|
movl mmu_cr4_features, %ecx
|
|
jecxz 1f # cr4 Pentium and higher, skip if zero
|
|
movl %ecx, %cr4; # turn PGE back on
|
|
1:
|
|
|
|
movl saved_context_esp, %esp
|
|
movl saved_context_ebp, %ebp
|
|
movl saved_context_ebx, %ebx
|
|
movl saved_context_esi, %esi
|
|
movl saved_context_edi, %edi
|
|
|
|
pushl saved_context_eflags
|
|
popfl
|
|
|
|
/* Saved in save_processor_state. */
|
|
movl $saved_context, %eax
|
|
lgdt saved_context_gdt_desc(%eax)
|
|
|
|
xorl %eax, %eax
|
|
|
|
ret
|