lkml.org 
[lkml]   [2017]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 5/5] x86/mm/kaiser: Disable the SYSCALL-64 trampoline along with KAISER
If we don't use KAISER we don't need the trampoline, use the old entry
code.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/kernel/cpu/common.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1442,7 +1442,10 @@ void syscall_init(void)
(entry_SYSCALL_64_trampoline - _entry_trampoline);

wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS);
- wrmsrl(MSR_LSTAR, SYSCALL64_entry_trampoline);
+ if (kaiser_enabled)
+ wrmsrl(MSR_LSTAR, SYSCALL64_entry_trampoline);
+ else
+ wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64);

#ifdef CONFIG_IA32_EMULATION
wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat);

\
 
 \ /
  Last update: 2017-11-27 23:36    [W:0.090 / U:1.892 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site