From: Borislav Petkov <bp@alien8.de>
To: X86 ML <x86@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH] x86/CPU: Remove outdated comment about SYSCALL targets
Date: Tue, 23 Aug 2016 19:23:56 +0200 [thread overview]
Message-ID: <20160823172356.15879-1-bp@alien8.de> (raw)
From: Borislav Petkov <bp@suse.de>
The comment probably meant some old AMD64 incarnation which most likely
never saw the light of day. STAR and LSTAR are two different registers
and STAR sets CS/SS(DS) selectors for *all* modes, not only 32-bit.
So simply remove that comment.
Signed-off-by: Borislav Petkov <bp@suse.de>
---
arch/x86/kernel/cpu/common.c | 5 -----
1 file changed, 5 deletions(-)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index ce7a4c17f1bc..06919427d451 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1310,11 +1310,6 @@ static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
/* May not be marked __init: used by software suspend */
void syscall_init(void)
{
- /*
- * LSTAR and STAR live in a bit strange symbiosis.
- * They both write to the same internal register. STAR allows to
- * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
- */
wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS);
wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64);
--
2.8.4
next reply other threads:[~2016-08-23 17:23 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-23 17:23 Borislav Petkov [this message]
2016-08-24 9:32 ` [tip:x86/asm] x86/entry: " tip-bot for Borislav Petkov
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