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author | Andy Lutomirski <luto@kernel.org> | 2016-02-24 12:18:49 -0800 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-03-03 15:07:30 -0800 |
commit | eeb241d4f8a1d0c343e0a19c99490e66b7eff346 (patch) | |
tree | a3f83df290723c823b9470cfb7cbdfe6431805d9 /arch/x86/entry | |
parent | 04100683e8f2792d9c715d5a253a260cb30fa3e3 (diff) | |
download | lwn-eeb241d4f8a1d0c343e0a19c99490e66b7eff346.tar.gz lwn-eeb241d4f8a1d0c343e0a19c99490e66b7eff346.zip |
x86/entry/compat: Add missing CLAC to entry_INT80_32
commit 3d44d51bd339766f0178f0cf2e8d048b4a4872aa upstream.
This doesn't seem to fix a regression -- I don't think the CLAC was
ever there.
I double-checked in a debugger: entries through the int80 gate do
not automatically clear AC.
Stable maintainers: I can provide a backport to 4.3 and earlier if
needed. This needs to be backported all the way to 3.10.
Reported-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 63bcff2a307b ("x86, smap: Add STAC and CLAC instructions to control user space access")
Link: http://lkml.kernel.org/r/b02b7e71ae54074be01fc171cbd4b72517055c0e.1456345086.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/entry')
-rw-r--r-- | arch/x86/entry/entry_64_compat.S | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 6a1ae3751e82..15cfebaa7688 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -267,6 +267,7 @@ ENTRY(entry_INT80_compat) * Interrupts are off on entry. */ PARAVIRT_ADJUST_EXCEPTION_FRAME + ASM_CLAC /* Do this early to minimize exposure */ SWAPGS /* |