Messages in this thread Patch in this message | | | From | Alexander Kuleshov <> | Subject | [PATCH] x86/head_64.S: do not use temporary register to check alignment | Date | Sat, 23 Jan 2016 12:50:28 +0600 |
| |
We are using temporary %rax register during checking of kernel address alignment. We can ged rid of it since testl instruction is safe and does not change value of the rbp register.
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Suggested-by: Brian Gerst <brgerst@gmail.com> --- arch/x86/kernel/head_64.S | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index ffdc0e8..7c21029 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -76,9 +76,7 @@ startup_64: subq $_text - __START_KERNEL_map, %rbp /* Is the address not 2M aligned? */ - movq %rbp, %rax - andl $~PMD_PAGE_MASK, %eax - testl %eax, %eax + testl $~PMD_PAGE_MASK, %ebp jnz bad_address /* -- 2.7.0.25.gfc10eb5
| |