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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-10 14:24:20 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-10 14:24:20 -0800 |
| commit | 3100e448e7d74489a96cb7b45d88fe6962774eaa (patch) | |
| tree | 53e46a702bd191ca43639b560d2bb1d3b0ad18c8 /arch/x86/Kconfig | |
| parent | c9f861c77269bc9950c16c6404a9476062241671 (diff) | |
| parent | 26893107aa717cd11010f0c278d02535defa1ac9 (diff) | |
Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 vdso updates from Ingo Molnar:
"Various vDSO updates from Andy Lutomirski, mostly cleanups and
reorganization to improve maintainability, but also some
micro-optimizations and robustization changes"
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86_64/vsyscall: Restore orig_ax after vsyscall seccomp
x86_64: Add a comment explaining the TASK_SIZE_MAX guard page
x86_64,vsyscall: Make vsyscall emulation configurable
x86_64, vsyscall: Rewrite comment and clean up headers in vsyscall code
x86_64, vsyscall: Turn vsyscalls all the way off when vsyscall==none
x86,vdso: Use LSL unconditionally for vgetcpu
x86: vdso: Fix build with older gcc
x86_64/vdso: Clean up vgetcpu init and merge the vdso initcalls
x86_64/vdso: Remove jiffies from the vvar page
x86/vdso: Make the PER_CPU segment 32 bits
x86/vdso: Make the PER_CPU segment start out accessed
x86/vdso: Change the PER_CPU segment to use struct desc_struct
x86_64/vdso: Move getcpu code from vsyscall_64.c to vdso/vma.c
x86_64/vsyscall: Move all of the gate_area code to vsyscall_64.c
Diffstat (limited to 'arch/x86/Kconfig')
| -rw-r--r-- | arch/x86/Kconfig | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 666ac6651c17..bea3a0159496 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -992,6 +992,24 @@ config X86_ESPFIX64 def_bool y depends on X86_16BIT && X86_64 +config X86_VSYSCALL_EMULATION + bool "Enable vsyscall emulation" if EXPERT + default y + depends on X86_64 + ---help--- + This enables emulation of the legacy vsyscall page. Disabling + it is roughly equivalent to booting with vsyscall=none, except + that it will also disable the helpful warning if a program + tries to use a vsyscall. With this option set to N, offending + programs will just segfault, citing addresses of the form + 0xffffffffff600?00. + + This option is required by many programs built before 2013, and + care should be used even with newer programs if set to N. + + Disabling this option saves about 7K of kernel size and + possibly 4K of additional runtime pagetable memory. + config TOSHIBA tristate "Toshiba Laptop support" depends on X86_32 |