Re: [RFC PATCH v4 2/9] x86/cet/ibt: User-mode indirect branch tracking support
From: Eugene Syromiatnikov <hidden>
Date: 2018-10-03 18:57:48
Also in:
linux-api, linux-arch, linux-mm, lkml
On Fri, Sep 21, 2018 at 08:05:46AM -0700, Yu-cheng Yu wrote:
quoted hunk ↗ jump to hunk
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index bffa9ef47832..230f65ee881e 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c
quoted hunk ↗ jump to hunk
@@ -434,6 +435,23 @@ static __init int setup_disable_shstk(char *s) __setup("no_cet_shstk", setup_disable_shstk); #endif +#ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER +static __init int setup_disable_ibt(char *s) +{ + /* require an exact match without trailing characters */ + if (strlen(s)) + return 0;
"s[0] (!= '\0')" will do the same check in constant time.