diff options
| author | Matt Fleming <matt@console-pimps.org> | 2014-04-08 13:14:00 +0100 |
|---|---|---|
| committer | Matt Fleming <matt.fleming@intel.com> | 2014-04-10 21:19:52 +0100 |
| commit | 7e8213c1f3acc064aef37813a39f13cbfe7c3ce7 (patch) | |
| tree | 6a24e3cd7ca9994d165bd38e83567ab546d01a92 /arch/x86/boot/compressed/head_64.S | |
| parent | 396f1a08db212138418b38f784e4bbe516d2fdb2 (diff) | |
| download | blackbird-obmc-linux-7e8213c1f3acc064aef37813a39f13cbfe7c3ce7.tar.gz blackbird-obmc-linux-7e8213c1f3acc064aef37813a39f13cbfe7c3ce7.zip | |
x86/efi: Correct EFI boot stub use of code32_start
code32_start should point at the start of the protected mode code, and
*not* at the beginning of the bzImage. This is much easier to do in
assembly so document that callers of make_boot_params() need to fill out
code32_start.
The fallout from this bug is that we would end up relocating the image
but copying the image at some offset, resulting in what appeared to be
memory corruption.
Reported-by: Thomas Bächler <thomas@archlinux.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'arch/x86/boot/compressed/head_64.S')
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 57e58a5fa210..0d558ee899ae 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -261,6 +261,8 @@ ENTRY(efi_pe_entry) cmpq $0,%rax je fail mov %rax, %rsi + leaq startup_32(%rip), %rax + movl %eax, BP_code32_start(%rsi) jmp 2f /* Skip the relocation */ handover_entry: @@ -284,12 +286,7 @@ fail: hlt jmp fail 2: - call 3f -3: - popq %rax - subq $3b, %rax - subq BP_pref_address(%rsi), %rax - add BP_code32_start(%esi), %eax + movl BP_code32_start(%esi), %eax leaq preferred_addr(%rax), %rax jmp *%rax |
