lkml.org 
[lkml]   [2018]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [tip:x86/pti] x86/retpoline: Fill return stack buffer on vmexit
On Fri, Jan 12, 2018 at 03:37:49AM -0800, tip-bot for David Woodhouse wrote:
> Commit-ID: 117cc7a908c83697b0b737d15ae1eb5943afe35b
> Gitweb: https://git.kernel.org/tip/117cc7a908c83697b0b737d15ae1eb5943afe35b
> Author: David Woodhouse <dwmw@amazon.co.uk>
> AuthorDate: Fri, 12 Jan 2018 11:11:27 +0000
> Committer: Thomas Gleixner <tglx@linutronix.de>
> CommitDate: Fri, 12 Jan 2018 12:33:37 +0100
>
> x86/retpoline: Fill return stack buffer on vmexit

...

> + /*
> + * A simpler FILL_RETURN_BUFFER macro. Don't make people use the CPP
> + * monstrosity above, manually.
> + */
> +.macro FILL_RETURN_BUFFER reg:req nr:req ftr:req
> +#ifdef CONFIG_RETPOLINE
> + ANNOTATE_NOSPEC_ALTERNATIVE
> + ALTERNATIVE "jmp .Lskip_rsb_\@", \
> + __stringify(__FILL_RETURN_BUFFER(\reg,\nr,%_ASM_SP)) \
> + \ftr
> +.Lskip_rsb_\@:
> +#endif
> +.endm

Looks unused to me. Was it ever gound to be used? If not:

---
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -121,20 +121,6 @@
#endif
.endm

- /*
- * A simpler FILL_RETURN_BUFFER macro. Don't make people use the CPP
- * monstrosity above, manually.
- */
-.macro FILL_RETURN_BUFFER reg:req nr:req ftr:req
-#ifdef CONFIG_RETPOLINE
- ANNOTATE_NOSPEC_ALTERNATIVE
- ALTERNATIVE "jmp .Lskip_rsb_\@", \
- __stringify(__FILL_RETURN_BUFFER(\reg,\nr,%_ASM_SP)) \
- \ftr
-.Lskip_rsb_\@:
-#endif
-.endm
-
#else /* __ASSEMBLY__ */

#define ANNOTATE_NOSPEC_ALTERNATIVE \
--
Regards/Gruss,
Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

\
 
 \ /
  Last update: 2018-01-14 23:27    [W:0.120 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site