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| author | Arvind Sankar <nivedita@alum.mit.edu> | 2020-03-08 09:08:41 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-03-08 09:58:15 +0100 |
| commit | 71ff44ac6cfaa1d8d3dff6c73636f4fb97b2be10 (patch) | |
| tree | 6d1ed220408fc63b2246560ddc88b1f789a7a0dd /arch/x86/boot/compressed | |
| parent | 3cdcd6899eaf454b2539c624fff5daf63c175a7a (diff) | |
| download | lwn-71ff44ac6cfaa1d8d3dff6c73636f4fb97b2be10.tar.gz lwn-71ff44ac6cfaa1d8d3dff6c73636f4fb97b2be10.zip | |
efi/x86: Respect 32-bit ABI in efi32_pe_entry()
verify_cpu() clobbers BX and DI. In case we have to return error, we need
to preserve them to respect the 32-bit calling convention.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200301230436.2246909-3-nivedita@alum.mit.edu
Link: https://lore.kernel.org/r/20200308080859.21568-11-ardb@kernel.org
Diffstat (limited to 'arch/x86/boot/compressed')
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 8105e8348607..920daf62dac2 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -660,7 +660,11 @@ SYM_DATA(efi_is64, .byte 1) SYM_FUNC_START(efi32_pe_entry) pushl %ebp + pushl %ebx + pushl %edi call verify_cpu // check for long mode support + popl %edi + popl %ebx testl %eax, %eax movl $0x80000003, %eax // EFI_UNSUPPORTED jnz 3f |