[patch V2 13/28] x86/speculation: Reorder the spec_v2 code
From: Thomas Gleixner
Date: Sun Nov 25 2018 - 13:57:26 EST
Reorder the code so it is better grouped.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/bugs.c | 168 ++++++++++++++++++++++-----------------------
1 file changed, 84 insertions(+), 84 deletions(-)
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -124,29 +124,6 @@ void __init check_bugs(void)
#endif
}
-/* The kernel command line selection */
-enum spectre_v2_mitigation_cmd {
- SPECTRE_V2_CMD_NONE,
- SPECTRE_V2_CMD_AUTO,
- SPECTRE_V2_CMD_FORCE,
- SPECTRE_V2_CMD_RETPOLINE,
- SPECTRE_V2_CMD_RETPOLINE_GENERIC,
- SPECTRE_V2_CMD_RETPOLINE_AMD,
-};
-
-static const char *spectre_v2_strings[] = {
- [SPECTRE_V2_NONE] = "Vulnerable",
- [SPECTRE_V2_RETPOLINE_GENERIC] = "Mitigation: Full generic retpoline",
- [SPECTRE_V2_RETPOLINE_AMD] = "Mitigation: Full AMD retpoline",
- [SPECTRE_V2_IBRS_ENHANCED] = "Mitigation: Enhanced IBRS",
-};
-
-#undef pr_fmt
-#define pr_fmt(fmt) "Spectre V2 : " fmt
-
-static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
- SPECTRE_V2_NONE;
-
void
x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest)
{
@@ -216,6 +193,12 @@ static void x86_amd_ssb_disable(void)
wrmsrl(MSR_AMD64_LS_CFG, msrval);
}
+#undef pr_fmt
+#define pr_fmt(fmt) "Spectre V2 : " fmt
+
+static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
+ SPECTRE_V2_NONE;
+
#ifdef RETPOLINE
static bool spectre_v2_bad_module;
@@ -237,18 +220,6 @@ static inline const char *spectre_v2_mod
static inline const char *spectre_v2_module_string(void) { return ""; }
#endif
-static void __init spec2_print_if_insecure(const char *reason)
-{
- if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
- pr_info("%s selected on command line.\n", reason);
-}
-
-static void __init spec2_print_if_secure(const char *reason)
-{
- if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
- pr_info("%s selected on command line.\n", reason);
-}
-
static inline bool match_option(const char *arg, int arglen, const char *opt)
{
int len = strlen(opt);
@@ -256,24 +227,53 @@ static inline bool match_option(const ch
return len == arglen && !strncmp(arg, opt, len);
}
+/* The kernel command line selection for spectre v2 */
+enum spectre_v2_mitigation_cmd {
+ SPECTRE_V2_CMD_NONE,
+ SPECTRE_V2_CMD_AUTO,
+ SPECTRE_V2_CMD_FORCE,
+ SPECTRE_V2_CMD_RETPOLINE,
+ SPECTRE_V2_CMD_RETPOLINE_GENERIC,
+ SPECTRE_V2_CMD_RETPOLINE_AMD,
+};
+
+static const char *spectre_v2_strings[] = {
+ [SPECTRE_V2_NONE] = "Vulnerable",
+ [SPECTRE_V2_RETPOLINE_GENERIC] = "Mitigation: Full generic retpoline",
+ [SPECTRE_V2_RETPOLINE_AMD] = "Mitigation: Full AMD retpoline",
+ [SPECTRE_V2_IBRS_ENHANCED] = "Mitigation: Enhanced IBRS",
+};
+
static const struct {
const char *option;
enum spectre_v2_mitigation_cmd cmd;
bool secure;
} mitigation_options[] = {
- { "off", SPECTRE_V2_CMD_NONE, false },
- { "on", SPECTRE_V2_CMD_FORCE, true },
- { "retpoline", SPECTRE_V2_CMD_RETPOLINE, false },
- { "retpoline,amd", SPECTRE_V2_CMD_RETPOLINE_AMD, false },
- { "retpoline,generic", SPECTRE_V2_CMD_RETPOLINE_GENERIC, false },
- { "auto", SPECTRE_V2_CMD_AUTO, false },
+ { "off", SPECTRE_V2_CMD_NONE, false },
+ { "on", SPECTRE_V2_CMD_FORCE, true },
+ { "retpoline", SPECTRE_V2_CMD_RETPOLINE, false },
+ { "retpoline,amd", SPECTRE_V2_CMD_RETPOLINE_AMD, false },
+ { "retpoline,generic", SPECTRE_V2_CMD_RETPOLINE_GENERIC, false },
+ { "auto", SPECTRE_V2_CMD_AUTO, false },
};
+static void __init spec2_print_if_insecure(const char *reason)
+{
+ if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+ pr_info("%s selected on command line.\n", reason);
+}
+
+static void __init spec2_print_if_secure(const char *reason)
+{
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+ pr_info("%s selected on command line.\n", reason);
+}
+
static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
{
+ enum spectre_v2_mitigation_cmd cmd = SPECTRE_V2_CMD_AUTO;
char arg[20];
int ret, i;
- enum spectre_v2_mitigation_cmd cmd = SPECTRE_V2_CMD_AUTO;
if (cmdline_find_option_bool(boot_command_line, "nospectre_v2"))
return SPECTRE_V2_CMD_NONE;
@@ -317,48 +317,6 @@ static enum spectre_v2_mitigation_cmd __
return cmd;
}
-static bool stibp_needed(void)
-{
- if (spectre_v2_enabled == SPECTRE_V2_NONE)
- return false;
-
- /* Enhanced IBRS makes using STIBP unnecessary. */
- if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
- return false;
-
- if (!boot_cpu_has(X86_FEATURE_STIBP))
- return false;
-
- return true;
-}
-
-static void update_stibp_msr(void *info)
-{
- wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
-}
-
-void arch_smt_update(void)
-{
- u64 mask;
-
- if (!stibp_needed())
- return;
-
- mutex_lock(&spec_ctrl_mutex);
-
- mask = x86_spec_ctrl_base & ~SPEC_CTRL_STIBP;
- if (sched_smt_active())
- mask |= SPEC_CTRL_STIBP;
-
- if (mask != x86_spec_ctrl_base) {
- pr_info("Spectre v2 cross-process SMT mitigation: %s STIBP\n",
- mask & SPEC_CTRL_STIBP ? "Enabling" : "Disabling");
- x86_spec_ctrl_base = mask;
- on_each_cpu(update_stibp_msr, NULL, 1);
- }
- mutex_unlock(&spec_ctrl_mutex);
-}
-
static void __init spectre_v2_select_mitigation(void)
{
enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
@@ -462,6 +420,48 @@ static void __init spectre_v2_select_mit
arch_smt_update();
}
+static bool stibp_needed(void)
+{
+ if (spectre_v2_enabled == SPECTRE_V2_NONE)
+ return false;
+
+ /* Enhanced IBRS makes using STIBP unnecessary. */
+ if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
+ return false;
+
+ if (!boot_cpu_has(X86_FEATURE_STIBP))
+ return false;
+
+ return true;
+}
+
+static void update_stibp_msr(void *info)
+{
+ wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+}
+
+void arch_smt_update(void)
+{
+ u64 mask;
+
+ if (!stibp_needed())
+ return;
+
+ mutex_lock(&spec_ctrl_mutex);
+
+ mask = x86_spec_ctrl_base & ~SPEC_CTRL_STIBP;
+ if (sched_smt_active())
+ mask |= SPEC_CTRL_STIBP;
+
+ if (mask != x86_spec_ctrl_base) {
+ pr_info("Spectre v2 cross-process SMT mitigation: %s STIBP\n",
+ mask & SPEC_CTRL_STIBP ? "Enabling" : "Disabling");
+ x86_spec_ctrl_base = mask;
+ on_each_cpu(update_stibp_msr, NULL, 1);
+ }
+ mutex_unlock(&spec_ctrl_mutex);
+}
+
#undef pr_fmt
#define pr_fmt(fmt) "Speculative Store Bypass: " fmt