Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1315527
| From | Alexander Kuleshov <kuleshovmail@gmail.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH] x86/head_64.S: do not use temporary register to check alignment |
| Date | 2016-01-23 08:00 +0100 |
| Message-ID | <qU0l4-7kW-11@gated-at.bofh.it> (permalink) |
| Organization | linux.* mail to news gateway |
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
Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread
[PATCH] x86/head_64.S: do not use temporary register to check alignment Alexander Kuleshov <kuleshovmail@gmail.com> - 2016-01-23 08:00 +0100 Re: [PATCH] x86/head_64.S: do not use temporary register to check alignment Borislav Petkov <bp@suse.de> - 2016-01-26 10:40 +0100
csiph-web