From: Andy Lutomirski <luto@kernel.org>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, Borislav Petkov <bp@alien8.de>,
Brian Gerst <brgerst@gmail.com>,
David Laight <David.Laight@aculab.com>,
Kees Cook <keescook@chromium.org>,
Peter Zijlstra <peterz@infradead.org>,
Andy Lutomirski <luto@kernel.org>
Subject: [RFC PTI 2/3] Revert "x86/mm/pti: Disable native VSYSCALL"
Date: Fri, 8 Dec 2017 11:59:10 -0800 [thread overview]
Message-ID: <d7c374c734cc0a47613f943ac17fdb8582ebd3c6.1512763129.git.luto@kernel.org> (raw)
In-Reply-To: <cover.1512763129.git.luto@kernel.org>
In-Reply-To: <cover.1512763129.git.luto@kernel.org>
This reverts commit 6a7b4041b853ecc653e2c1dda5b736ab5fd29357.
With the PGD-propagation logic simplified, there's no need for this.
---
arch/x86/Kconfig | 8 --------
1 file changed, 8 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 411838058194..babb1e53b0a6 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2233,9 +2233,6 @@ choice
config LEGACY_VSYSCALL_NATIVE
bool "Native"
- # The VSYSCALL page comes from the kernel page tables
- # and is not available when PAGE_TABLE_ISOLATION is enabled.
- depends on !PAGE_TABLE_ISOLATION
help
Actual executable code is located in the fixed vsyscall
address mapping, implementing time() efficiently. Since
@@ -2253,11 +2250,6 @@ choice
exploits. This configuration is recommended when userspace
still uses the vsyscall area.
- When PAGE_TABLE_ISOLATION is enabled, the vsyscall area will become
- unreadable. This emulation option still works, but PAGE_TABLE_ISOLATION
- will make it harder to do things like trace code using the
- emulation.
-
config LEGACY_VSYSCALL_NONE
bool "None"
help
--
2.13.6
next prev parent reply other threads:[~2017-12-08 19:59 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-08 19:59 [RFC PTI 0/3] Clean up pgd handling and fix VSYSCALL and LDT Andy Lutomirski
2017-12-08 19:59 ` [RFC PTI 1/3] x86/pti: Vastly simplify pgd synchronization Andy Lutomirski
2017-12-08 20:17 ` Dave Hansen
2017-12-08 20:49 ` Andy Lutomirski
2017-12-08 20:48 ` Dave Hansen
2017-12-08 19:59 ` Andy Lutomirski [this message]
2017-12-08 19:59 ` [RFC PTI 3/3] x86/pti: Put the LDT in its own PGD if PTI is on Andy Lutomirski
2017-12-08 21:48 ` Thomas Gleixner
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