4.14-stable review patch. If anyone has any objections, please let me know.
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From: Zhenzhong Duan zhenzhong.duan@oracle.com
commit ef014aae8f1cd2793e4e014bbb102bed53f852b7 upstream
Now that CONFIG_RETPOLINE hard depends on compiler support, there is no reason to keep the minimal retpoline support around which only provided basic protection in the assembly files.
Suggested-by: Peter Zijlstra peterz@infradead.org Signed-off-by: Zhenzhong Duan zhenzhong.duan@oracle.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: David Woodhouse dwmw@amazon.co.uk Cc: Borislav Petkov bp@suse.de Cc: H. Peter Anvin hpa@zytor.com Cc: Konrad Rzeszutek Wilk konrad.wilk@oracle.com Cc: srinivas.eeda@oracle.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/f06f0a89-5587-45db-8ed2-0a9d6638d5c0@default Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/include/asm/nospec-branch.h | 3 --- arch/x86/kernel/cpu/bugs.c | 13 ++----------- 2 files changed, 2 insertions(+), 14 deletions(-)
--- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -221,11 +221,8 @@ /* The Spectre V2 mitigation variants */ enum spectre_v2_mitigation { SPECTRE_V2_NONE, - SPECTRE_V2_RETPOLINE_MINIMAL, - SPECTRE_V2_RETPOLINE_MINIMAL_AMD, SPECTRE_V2_RETPOLINE_GENERIC, SPECTRE_V2_RETPOLINE_AMD, - SPECTRE_V2_IBRS, SPECTRE_V2_IBRS_ENHANCED, };
--- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -134,8 +134,6 @@ enum spectre_v2_mitigation_cmd {
static const char *spectre_v2_strings[] = { [SPECTRE_V2_NONE] = "Vulnerable", - [SPECTRE_V2_RETPOLINE_MINIMAL] = "Vulnerable: Minimal generic ASM retpoline", - [SPECTRE_V2_RETPOLINE_MINIMAL_AMD] = "Vulnerable: Minimal AMD ASM retpoline", [SPECTRE_V2_RETPOLINE_GENERIC] = "Mitigation: Full generic retpoline", [SPECTRE_V2_RETPOLINE_AMD] = "Mitigation: Full AMD retpoline", [SPECTRE_V2_IBRS_ENHANCED] = "Mitigation: Enhanced IBRS", @@ -249,11 +247,6 @@ static void __init spec2_print_if_secure pr_info("%s selected on command line.\n", reason); }
-static inline bool retp_compiler(void) -{ - return __is_defined(CONFIG_RETPOLINE); -} - static inline bool match_option(const char *arg, int arglen, const char *opt) { int len = strlen(opt); @@ -414,14 +407,12 @@ retpoline_auto: pr_err("Spectre mitigation: LFENCE not serializing, switching to generic retpoline\n"); goto retpoline_generic; } - mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_AMD : - SPECTRE_V2_RETPOLINE_MINIMAL_AMD; + mode = SPECTRE_V2_RETPOLINE_AMD; setup_force_cpu_cap(X86_FEATURE_RETPOLINE_AMD); setup_force_cpu_cap(X86_FEATURE_RETPOLINE); } else { retpoline_generic: - mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_GENERIC : - SPECTRE_V2_RETPOLINE_MINIMAL; + mode = SPECTRE_V2_RETPOLINE_GENERIC; setup_force_cpu_cap(X86_FEATURE_RETPOLINE); }