[PATCH RFC 1/7] x86: cpu: bugs.c: remove init attribute from functions and variables

From: Mihai Carabas
Date: Thu Jul 02 2020 - 11:24:07 EST

in order to be able to call them after the system has booted.

Signed-off-by: Mihai Carabas <mihai.carabas@xxxxxxxxxx>
---
arch/x86/kernel/cpu/bugs.c | 76 ++++++++++++++++++++++----------------------
arch/x86/kernel/cpu/common.c | 4 +--
arch/x86/kernel/cpu/cpu.h | 4 +--
arch/x86/kernel/cpu/tsx.c | 6 ++--
kernel/cpu.c | 2 +-
5 files changed, 46 insertions(+), 46 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 0b71970..7091947 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -34,14 +34,14 @@

#include "cpu.h"

-static void __init spectre_v1_select_mitigation(void);
-static void __init spectre_v2_select_mitigation(void);
-static void __init ssb_select_mitigation(void);
-static void __init l1tf_select_mitigation(void);
-static void __init mds_select_mitigation(void);
-static void __init mds_print_mitigation(void);
-static void __init taa_select_mitigation(void);
-static void __init srbds_select_mitigation(void);
+static void spectre_v1_select_mitigation(void);
+static void spectre_v2_select_mitigation(void);
+static void ssb_select_mitigation(void);
+static void l1tf_select_mitigation(void);
+static void mds_select_mitigation(void);
+static void mds_print_mitigation(void);
+static void taa_select_mitigation(void);
+static void srbds_select_mitigation(void);

/* The base value of the SPEC_CTRL MSR that always has to be preserved. */
u64 x86_spec_ctrl_base;
@@ -52,14 +52,14 @@
* The vendor and possibly platform specific bits which can be modified in
* x86_spec_ctrl_base.
*/
-static u64 __ro_after_init x86_spec_ctrl_mask = SPEC_CTRL_IBRS;
+static u64 x86_spec_ctrl_mask = SPEC_CTRL_IBRS;

/*
* AMD specific MSR info for Speculative Store Bypass control.
* x86_amd_ls_cfg_ssbd_mask is initialized in identify_boot_cpu().
*/
-u64 __ro_after_init x86_amd_ls_cfg_base;
-u64 __ro_after_init x86_amd_ls_cfg_ssbd_mask;
+u64 x86_amd_ls_cfg_base;
+u64 x86_amd_ls_cfg_ssbd_mask;

/* Control conditional STIBP in switch_to() */
DEFINE_STATIC_KEY_FALSE(switch_to_cond_stibp);
@@ -75,7 +75,7 @@
DEFINE_STATIC_KEY_FALSE(mds_idle_clear);
EXPORT_SYMBOL_GPL(mds_idle_clear);

-void __init check_bugs(void)
+void __ref check_bugs(void)
{
identify_boot_cpu();

@@ -228,7 +228,7 @@ static void x86_amd_ssb_disable(void)
#define pr_fmt(fmt) "MDS: " fmt

/* Default mitigation for MDS-affected CPUs */
-static enum mds_mitigations mds_mitigation __ro_after_init = MDS_MITIGATION_FULL;
+static enum mds_mitigations mds_mitigation = MDS_MITIGATION_FULL;
static bool mds_nosmt __ro_after_init = false;

static const char * const mds_strings[] = {
@@ -237,7 +237,7 @@ static void x86_amd_ssb_disable(void)
[MDS_MITIGATION_VMWERV] = "Vulnerable: Clear CPU buffers attempted, no microcode",
};

-static void __init mds_select_mitigation(void)
+static void mds_select_mitigation(void)
{
if (!boot_cpu_has_bug(X86_BUG_MDS) || cpu_mitigations_off()) {
mds_mitigation = MDS_MITIGATION_OFF;
@@ -256,7 +256,7 @@ static void __init mds_select_mitigation(void)
}
}

-static void __init mds_print_mitigation(void)
+static void mds_print_mitigation(void)
{
if (!boot_cpu_has_bug(X86_BUG_MDS) || cpu_mitigations_off())
return;
@@ -296,7 +296,7 @@ enum taa_mitigations {
};

/* Default mitigation for TAA-affected CPUs */
-static enum taa_mitigations taa_mitigation __ro_after_init = TAA_MITIGATION_VERW;
+static enum taa_mitigations taa_mitigation = TAA_MITIGATION_VERW;
static bool taa_nosmt __ro_after_init;

static const char * const taa_strings[] = {
@@ -306,7 +306,7 @@ enum taa_mitigations {
[TAA_MITIGATION_TSX_DISABLED] = "Mitigation: TSX disabled",
};

-static void __init taa_select_mitigation(void)
+static void taa_select_mitigation(void)
{
u64 ia32_cap;

@@ -410,7 +410,7 @@ enum srbds_mitigations {
SRBDS_MITIGATION_HYPERVISOR,
};

-static enum srbds_mitigations srbds_mitigation __ro_after_init = SRBDS_MITIGATION_FULL;
+static enum srbds_mitigations srbds_mitigation = SRBDS_MITIGATION_FULL;

static const char * const srbds_strings[] = {
[SRBDS_MITIGATION_OFF] = "Vulnerable",
@@ -452,7 +452,7 @@ void update_srbds_msr(void)
wrmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
}

-static void __init srbds_select_mitigation(void)
+static void srbds_select_mitigation(void)
{
u64 ia32_cap;

@@ -498,7 +498,7 @@ enum spectre_v1_mitigation {
SPECTRE_V1_MITIGATION_AUTO,
};

-static enum spectre_v1_mitigation spectre_v1_mitigation __ro_after_init =
+static enum spectre_v1_mitigation spectre_v1_mitigation =
SPECTRE_V1_MITIGATION_AUTO;

static const char * const spectre_v1_strings[] = {
@@ -527,7 +527,7 @@ static bool smap_works_speculatively(void)
return true;
}

-static void __init spectre_v1_select_mitigation(void)
+static void spectre_v1_select_mitigation(void)
{
if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off()) {
spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
@@ -585,12 +585,12 @@ static int __init nospectre_v1_cmdline(char *str)
#undef pr_fmt
#define pr_fmt(fmt) "Spectre V2 : " fmt

-static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
+static enum spectre_v2_mitigation spectre_v2_enabled =
SPECTRE_V2_NONE;

-static enum spectre_v2_user_mitigation spectre_v2_user_stibp __ro_after_init =
+static enum spectre_v2_user_mitigation spectre_v2_user_stibp =
SPECTRE_V2_USER_NONE;
-static enum spectre_v2_user_mitigation spectre_v2_user_ibpb __ro_after_init =
+static enum spectre_v2_user_mitigation spectre_v2_user_ibpb =
SPECTRE_V2_USER_NONE;

#ifdef CONFIG_RETPOLINE
@@ -653,7 +653,7 @@ enum spectre_v2_user_cmd {
const char *option;
enum spectre_v2_user_cmd cmd;
bool secure;
-} v2_user_options[] __initconst = {
+} v2_user_options[] = {
{ "auto", SPECTRE_V2_USER_CMD_AUTO, false },
{ "off", SPECTRE_V2_USER_CMD_NONE, false },
{ "on", SPECTRE_V2_USER_CMD_FORCE, true },
@@ -663,13 +663,13 @@ enum spectre_v2_user_cmd {
{ "seccomp,ibpb", SPECTRE_V2_USER_CMD_SECCOMP_IBPB, false },
};

-static void __init spec_v2_user_print_cond(const char *reason, bool secure)
+static void spec_v2_user_print_cond(const char *reason, bool secure)
{
if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2) != secure)
pr_info("spectre_v2_user=%s forced on command line.\n", reason);
}

-static enum spectre_v2_user_cmd __init
+static enum spectre_v2_user_cmd
spectre_v2_parse_user_cmdline(enum spectre_v2_mitigation_cmd v2_cmd)
{
char arg[20];
@@ -701,7 +701,7 @@ static void __init spec_v2_user_print_cond(const char *reason, bool secure)
return SPECTRE_V2_USER_CMD_AUTO;
}

-static void __init
+static void
spectre_v2_user_select_mitigation(enum spectre_v2_mitigation_cmd v2_cmd)
{
enum spectre_v2_user_mitigation mode = SPECTRE_V2_USER_NONE;
@@ -801,7 +801,7 @@ static void __init spec_v2_user_print_cond(const char *reason, bool secure)
const char *option;
enum spectre_v2_mitigation_cmd cmd;
bool secure;
-} mitigation_options[] __initconst = {
+} mitigation_options[] = {
{ "off", SPECTRE_V2_CMD_NONE, false },
{ "on", SPECTRE_V2_CMD_FORCE, true },
{ "retpoline", SPECTRE_V2_CMD_RETPOLINE, false },
@@ -810,13 +810,13 @@ static void __init spec_v2_user_print_cond(const char *reason, bool secure)
{ "auto", SPECTRE_V2_CMD_AUTO, false },
};

-static void __init spec_v2_print_cond(const char *reason, bool secure)
+static void spec_v2_print_cond(const char *reason, bool secure)
{
if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2) != secure)
pr_info("%s selected on command line.\n", reason);
}

-static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
+static enum spectre_v2_mitigation_cmd spectre_v2_parse_cmdline(void)
{
enum spectre_v2_mitigation_cmd cmd = SPECTRE_V2_CMD_AUTO;
char arg[20];
@@ -862,7 +862,7 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
return cmd;
}

-static void __init spectre_v2_select_mitigation(void)
+static void spectre_v2_select_mitigation(void)
{
enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
enum spectre_v2_mitigation mode = SPECTRE_V2_NONE;
@@ -1061,7 +1061,7 @@ void cpu_bugs_smt_update(void)
#undef pr_fmt
#define pr_fmt(fmt) "Speculative Store Bypass: " fmt

-static enum ssb_mitigation ssb_mode __ro_after_init = SPEC_STORE_BYPASS_NONE;
+static enum ssb_mitigation ssb_mode = SPEC_STORE_BYPASS_NONE;

/* The kernel command line selection */
enum ssb_mitigation_cmd {
@@ -1082,7 +1082,7 @@ enum ssb_mitigation_cmd {
static const struct {
const char *option;
enum ssb_mitigation_cmd cmd;
-} ssb_mitigation_options[] __initconst = {
+} ssb_mitigation_options[] = {
{ "auto", SPEC_STORE_BYPASS_CMD_AUTO }, /* Platform decides */
{ "on", SPEC_STORE_BYPASS_CMD_ON }, /* Disable Speculative Store Bypass */
{ "off", SPEC_STORE_BYPASS_CMD_NONE }, /* Don't touch Speculative Store Bypass */
@@ -1090,7 +1090,7 @@ enum ssb_mitigation_cmd {
{ "seccomp", SPEC_STORE_BYPASS_CMD_SECCOMP }, /* Disable Speculative Store Bypass via prctl and seccomp */
};

-static enum ssb_mitigation_cmd __init ssb_parse_cmdline(void)
+static enum ssb_mitigation_cmd ssb_parse_cmdline(void)
{
enum ssb_mitigation_cmd cmd = SPEC_STORE_BYPASS_CMD_AUTO;
char arg[20];
@@ -1122,7 +1122,7 @@ static enum ssb_mitigation_cmd __init ssb_parse_cmdline(void)
return cmd;
}

-static enum ssb_mitigation __init __ssb_select_mitigation(void)
+static enum ssb_mitigation __ssb_select_mitigation(void)
{
enum ssb_mitigation mode = SPEC_STORE_BYPASS_NONE;
enum ssb_mitigation_cmd cmd;
@@ -1402,7 +1402,7 @@ void x86_spec_ctrl_setup_ap(void)
#define pr_fmt(fmt) "L1TF: " fmt

/* Default mitigation for L1TF-affected CPUs */
-enum l1tf_mitigations l1tf_mitigation __ro_after_init = L1TF_MITIGATION_FLUSH;
+enum l1tf_mitigations l1tf_mitigation = L1TF_MITIGATION_FLUSH;
#if IS_ENABLED(CONFIG_KVM_INTEL)
EXPORT_SYMBOL_GPL(l1tf_mitigation);
#endif
@@ -1448,7 +1448,7 @@ static void override_cache_bits(struct cpuinfo_x86 *c)
}
}

-static void __init l1tf_select_mitigation(void)
+static void l1tf_select_mitigation(void)
{
u64 half_pa;

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 95c090a..c11daa6 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1018,7 +1018,7 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
#define VULNWL_HYGON(family, whitelist) \
VULNWL(HYGON, family, X86_MODEL_ANY, whitelist)

-static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
+static const struct x86_cpu_id cpu_vuln_whitelist[] = {
VULNWL(ANY, 4, X86_MODEL_ANY, NO_SPECULATION),
VULNWL(CENTAUR, 5, X86_MODEL_ANY, NO_SPECULATION),
VULNWL(INTEL, 5, X86_MODEL_ANY, NO_SPECULATION),
@@ -1094,7 +1094,7 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
{}
};

-static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long which)
+static bool cpu_matches(const struct x86_cpu_id *table, unsigned long which)
{
const struct x86_cpu_id *m = x86_match_cpu(table);

diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index 9d03369..bf025b8 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -51,9 +51,9 @@ enum tsx_ctrl_states {
TSX_CTRL_NOT_SUPPORTED,
};

-extern __ro_after_init enum tsx_ctrl_states tsx_ctrl_state;
+extern enum tsx_ctrl_states tsx_ctrl_state;

-extern void __init tsx_init(void);
+extern void tsx_init(void);
extern void tsx_enable(void);
extern void tsx_disable(void);
#else
diff --git a/arch/x86/kernel/cpu/tsx.c b/arch/x86/kernel/cpu/tsx.c
index e2ad30e..7c46581 100644
--- a/arch/x86/kernel/cpu/tsx.c
+++ b/arch/x86/kernel/cpu/tsx.c
@@ -17,7 +17,7 @@
#undef pr_fmt
#define pr_fmt(fmt) "tsx: " fmt

-enum tsx_ctrl_states tsx_ctrl_state __ro_after_init = TSX_CTRL_NOT_SUPPORTED;
+enum tsx_ctrl_states tsx_ctrl_state = TSX_CTRL_NOT_SUPPORTED;

void tsx_disable(void)
{
@@ -58,7 +58,7 @@ void tsx_enable(void)
wrmsrl(MSR_IA32_TSX_CTRL, tsx);
}

-static bool __init tsx_ctrl_is_supported(void)
+static bool tsx_ctrl_is_supported(void)
{
u64 ia32_cap = x86_read_arch_cap_msr();

@@ -84,7 +84,7 @@ static enum tsx_ctrl_states x86_get_tsx_auto_mode(void)
return TSX_CTRL_ENABLE;
}

-void __init tsx_init(void)
+void tsx_init(void)
{
char arg[5] = {};
int ret;
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 6ff2578..fe67a01 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -391,7 +391,7 @@ void __weak arch_smt_update(void) { }
#ifdef CONFIG_HOTPLUG_SMT
enum cpuhp_smt_control cpu_smt_control __read_mostly = CPU_SMT_ENABLED;

-void __init cpu_smt_disable(bool force)
+void cpu_smt_disable(bool force)
{
if (!cpu_smt_possible())
return;
--
1.8.3.1