diff options
Diffstat (limited to 'arch/x86/Kconfig')
| -rw-r--r-- | arch/x86/Kconfig | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e368fc0daa4a..6ae7fa4b8eb7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2523,6 +2523,25 @@ config CPU_UNRET_ENTRY help Compile the kernel with support for the retbleed=unret mitigation. +config CALL_DEPTH_TRACKING + bool "Mitigate RSB underflow with call depth tracking" + depends on CPU_SUP_INTEL && HAVE_CALL_THUNKS + select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE + select CALL_THUNKS + default y + help + Compile the kernel with call depth tracking to mitigate the Intel + SKL Return-Speculation-Buffer (RSB) underflow issue. The + mitigation is off by default and needs to be enabled on the + kernel command line via the retbleed=stuff option. For + non-affected systems the overhead of this option is marginal as + the call depth tracking is using run-time generated call thunks + in a compiler generated padding area and call patching. This + increases text size by ~5%. For non affected systems this space + is unused. On affected SKL systems this results in a significant + performance gain over the IBRS mitigation. + + config CPU_IBPB_ENTRY bool "Enable IBPB on kernel entry" depends on CPU_SUP_AMD && X86_64 |