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| author | Andy Lutomirski <luto@amacapital.net> | 2011-11-07 16:33:41 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2011-12-05 12:17:29 +0100 |
| commit | 2e57ae0515124af45dd889bfbd4840fd40fcc07d (patch) | |
| tree | 9c11c35755f8c09555faaa92399b6bf4096bcbdd | |
| parent | 4fc3490114bb159bd4fff1b3c96f4320fe6fb08f (diff) | |
| download | linux-stable-2e57ae0515124af45dd889bfbd4840fd40fcc07d.tar.gz linux-stable-2e57ae0515124af45dd889bfbd4840fd40fcc07d.tar.bz2 linux-stable-2e57ae0515124af45dd889bfbd4840fd40fcc07d.zip | |
x86: Default to vsyscall=emulate
This essentially reverts:
2b666859ec32: x86: Default to vsyscall=native for now
The ABI breakage should now be fixed by:
commit 48c4206f5b02f28c4c78a1f5b491d3772fb64fb9
Author: Andy Lutomirski <luto@mit.edu>
Date: Thu Oct 20 08:48:19 2011 -0700
x86-64: Set siginfo and context on vsyscall emulation faults
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/93154af3b2b6d208906ae02d80d92cf60c6fa94f.1320712291.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | Documentation/kernel-parameters.txt | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/vsyscall_64.c | 2 |
2 files changed, 4 insertions, 5 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index a0c5c5f4fce6..ce7fc8b3e2c0 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2750,11 +2750,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. functions are at fixed addresses, they make nice targets for exploits that can control RIP. - emulate Vsyscalls turn into traps and are emulated - reasonably safely. + emulate [default] Vsyscalls turn into traps and are + emulated reasonably safely. - native [default] Vsyscalls are native syscall - instructions. + native Vsyscalls are native syscall instructions. This is a little bit faster than trapping and makes a few dynamic recompilers work better than they would in emulation mode. diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 8084beccd64e..b07ba9393564 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -57,7 +57,7 @@ DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data) = .lock = __SEQLOCK_UNLOCKED(__vsyscall_gtod_data.lock), }; -static enum { EMULATE, NATIVE, NONE } vsyscall_mode = NATIVE; +static enum { EMULATE, NATIVE, NONE } vsyscall_mode = EMULATE; static int __init vsyscall_setup(char *str) { |