diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2021-12-04 14:43:44 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-05-15 20:18:51 +0200 |
| commit | 370d33da35e31c1544eb77bcf2539f09b1064b9c (patch) | |
| tree | e9f521fe06556cd39cdb1b888ef466e944076c82 /arch/x86/Kconfig | |
| parent | d11f96d0c0c30e6ed73049c752a1ca7621e7062f (diff) | |
x86: Add straight-line-speculation mitigation
[ Upstream commit e463a09af2f0677b9485a7e8e4e70b396b2ffb6f ]
Make use of an upcoming GCC feature to mitigate
straight-line-speculation for x86:
https://gcc.gnu.org/g:53a643f8568067d7700a9f2facc8ba39974973d3
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952
https://bugs.llvm.org/show_bug.cgi?id=52323
It's built tested on x86_64-allyesconfig using GCC-12 and GCC-11.
Maintenance overhead of this should be fairly low due to objtool
validation.
Size overhead of all these additional int3 instructions comes to:
text data bss dec hex filename
22267751 6933356 2011368 31212475 1dc43bb defconfig-build/vmlinux
22804126 6933356 1470696 31208178 1dc32f2 defconfig-build/vmlinux.sls
Or roughly 2.4% additional text.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134908.140103474@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/Kconfig')
| -rw-r--r-- | arch/x86/Kconfig | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 819f8c2e2c67..d02b04d30096 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -468,6 +468,18 @@ config RETPOLINE branches. Requires a compiler with -mindirect-branch=thunk-extern support for full protection. The kernel may run slower. +config CC_HAS_SLS + def_bool $(cc-option,-mharden-sls=all) + +config SLS + bool "Mitigate Straight-Line-Speculation" + depends on CC_HAS_SLS && X86_64 + default n + help + Compile the kernel with straight-line-speculation options to guard + against straight line speculation. The kernel image might be slightly + larger. + config X86_CPU_RESCTRL bool "x86 CPU resource control support" depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) |