diff options
Diffstat (limited to 'arch/x86/lib/memcpy_64.S')
| -rw-r--r-- | arch/x86/lib/memcpy_64.S | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index f01a88391c98..c3b527a9f95d 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -265,9 +265,23 @@ EXPORT_SYMBOL_GPL(__memcpy_mcsafe) mov %ecx, %eax ret + /* + * For write fault handling, given the destination is unaligned, + * we handle faults on multi-byte writes with a byte-by-byte + * copy up to the write-protected page. + */ +.E_write_words: + shll $3, %ecx + addl %edx, %ecx + movl %ecx, %edx + jmp mcsafe_handle_tail + .previous _ASM_EXTABLE_FAULT(.L_read_leading_bytes, .E_leading_bytes) _ASM_EXTABLE_FAULT(.L_read_words, .E_read_words) _ASM_EXTABLE_FAULT(.L_read_trailing_bytes, .E_trailing_bytes) + _ASM_EXTABLE(.L_write_leading_bytes, .E_leading_bytes) + _ASM_EXTABLE(.L_write_words, .E_write_words) + _ASM_EXTABLE(.L_write_trailing_bytes, .E_trailing_bytes) #endif |