diff options
| author | Kirill A. Shutemov <[email protected]> | 2018-02-26 21:04:50 +0300 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2018-03-12 09:37:25 +0100 |
| commit | 32fcefa2bfc8961987e91d1daeb00624b4176d2e (patch) | |
| tree | 768ee7da21d1746c14f4aeceb7683763157f0120 | |
| parent | fb5268354d20b82c12569e325b0d051c09f983f7 (diff) | |
x86/boot/compressed/64: Set up trampoline memory
This patch clears up trampoline memory and copies trampoline code in
place. It's not yet used though.
Tested-by: Borislav Petkov <[email protected]>
Signed-off-by: Kirill A. Shutemov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Cyrill Gorcunov <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 3 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/pgtable.h | 9 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/pgtable_64.c | 7 |
3 files changed, 18 insertions, 1 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 8ba0582c65d5..c813cb004056 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -501,8 +501,9 @@ relocated: jmp *%rax .code32 +ENTRY(trampoline_32bit_src) compatible_mode: - /* Setup data and stack segments */ + /* Set up data and stack segments */ movl $__KERNEL_DS, %eax movl %eax, %ds movl %eax, %ss diff --git a/arch/x86/boot/compressed/pgtable.h b/arch/x86/boot/compressed/pgtable.h index 57722a2fe2a0..91f75638f6e6 100644 --- a/arch/x86/boot/compressed/pgtable.h +++ b/arch/x86/boot/compressed/pgtable.h @@ -3,9 +3,18 @@ #define TRAMPOLINE_32BIT_SIZE (2 * PAGE_SIZE) +#define TRAMPOLINE_32BIT_PGTABLE_OFFSET 0 + +#define TRAMPOLINE_32BIT_CODE_OFFSET PAGE_SIZE +#define TRAMPOLINE_32BIT_CODE_SIZE 0x60 + +#define TRAMPOLINE_32BIT_STACK_END TRAMPOLINE_32BIT_SIZE + #ifndef __ASSEMBLER__ extern unsigned long *trampoline_32bit; +extern void trampoline_32bit_src(void *return_ptr); + #endif /* __ASSEMBLER__ */ #endif /* BOOT_COMPRESSED_PAGETABLE_H */ diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index 01d08d3e3e43..810c2c32d98e 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -76,6 +76,13 @@ struct paging_config paging_prepare(void) /* Preserve trampoline memory */ memcpy(trampoline_save, trampoline_32bit, TRAMPOLINE_32BIT_SIZE); + /* Clear trampoline memory first */ + memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE); + + /* Copy trampoline code in place */ + memcpy(trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET / sizeof(unsigned long), + &trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE); + return paging_config; } |