Patch "x86/cpu/bugs: Make retpoline module warning conditional" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    x86/cpu/bugs: Make retpoline module warning conditional

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-cpu-bugs-make-retpoline-module-warning-conditional.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Feb  8 03:30:27 CET 2018
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sat, 27 Jan 2018 15:45:14 +0100
Subject: x86/cpu/bugs: Make retpoline module warning conditional

From: Thomas Gleixner <tglx@linutronix.de>

(cherry picked from commit e383095c7fe8d218e00ec0f83e4b95ed4e627b02)

If sysfs is disabled and RETPOLINE not defined:

arch/x86/kernel/cpu/bugs.c:97:13: warning: ‘spectre_v2_bad_module’ defined but not used
[-Wunused-variable]
 static bool spectre_v2_bad_module;

Hide it.

Fixes: caf7501a1b4e ("module/retpoline: Warn about missing retpoline in module")
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/kernel/cpu/bugs.c |   14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -93,9 +93,10 @@ static const char *spectre_v2_strings[]
 #define pr_fmt(fmt)     "Spectre V2 : " fmt
 
 static enum spectre_v2_mitigation spectre_v2_enabled = SPECTRE_V2_NONE;
-static bool spectre_v2_bad_module;
 
 #ifdef RETPOLINE
+static bool spectre_v2_bad_module;
+
 bool retpoline_module_ok(bool has_retpoline)
 {
 	if (spectre_v2_enabled == SPECTRE_V2_NONE || has_retpoline)
@@ -105,6 +106,13 @@ bool retpoline_module_ok(bool has_retpol
 	spectre_v2_bad_module = true;
 	return false;
 }
+
+static inline const char *spectre_v2_module_string(void)
+{
+	return spectre_v2_bad_module ? " - vulnerable module loaded" : "";
+}
+#else
+static inline const char *spectre_v2_module_string(void) { return ""; }
 #endif
 
 static void __init spec2_print_if_insecure(const char *reason)
@@ -299,7 +307,7 @@ ssize_t cpu_show_spectre_v2(struct devic
 		return sprintf(buf, "Not affected\n");
 
 	return sprintf(buf, "%s%s%s\n", spectre_v2_strings[spectre_v2_enabled],
-		       boot_cpu_has(X86_FEATURE_IBPB) ? ", IPBP" : "",
-		       spectre_v2_bad_module ? " - vulnerable module loaded" : "");
+		       boot_cpu_has(X86_FEATURE_IBPB) ? ", IBPB" : "",
+		       spectre_v2_module_string());
 }
 #endif


Patches currently in stable-queue which might be from tglx@linutronix.de are

queue-4.9/x86-entry-64-push-extra-regs-right-away.patch
queue-4.9/kvm-vmx-allow-direct-access-to-msr_ia32_spec_ctrl.patch
queue-4.9/kvm-x86-add-ibpb-support.patch
queue-4.9/kvm-svm-allow-direct-access-to-msr_ia32_spec_ctrl.patch
queue-4.9/x86-cpufeatures-add-intel-feature-bits-for-speculation-control.patch
queue-4.9/x86-retpoline-simplify-vmexit_fill_rsb.patch
queue-4.9/x86-paravirt-remove-noreplace-paravirt-cmdline-option.patch
queue-4.9/x86-cpufeatures-clean-up-spectre-v2-related-cpuid-flags.patch
queue-4.9/documentation-document-array_index_nospec.patch
queue-4.9/x86-usercopy-replace-open-coded-stac-clac-with-__uaccess_-begin-end.patch
queue-4.9/x86-asm-move-status-from-thread_struct-to-thread_info.patch
queue-4.9/x86-cpufeatures-add-cpuid_7_edx-cpuid-leaf.patch
queue-4.9/kvm-x86-make-indirect-calls-in-emulator-speculation-safe.patch
queue-4.9/x86-microcode-amd-do-not-load-when-running-on-a-hypervisor.patch
queue-4.9/x86-entry-64-remove-the-syscall64-fast-path.patch
queue-4.9/x86-cpufeature-blacklist-spec_ctrl-pred_cmd-on-early-spectre-v2-microcodes.patch
queue-4.9/x86-nospec-fix-header-guards-names.patch
queue-4.9/x86-retpoline-avoid-retpolines-for-built-in-__init-functions.patch
queue-4.9/vfs-fdtable-prevent-bounds-check-bypass-via-speculative-execution.patch
queue-4.9/x86-uaccess-use-__uaccess_begin_nospec-and-uaccess_try_nospec.patch
queue-4.9/x86-cpu-bugs-make-retpoline-module-warning-conditional.patch
queue-4.9/x86-asm-fix-inline-asm-call-constraints-for-gcc-4.4.patch
queue-4.9/x86-spectre-check-config_retpoline-in-command-line-parser.patch
queue-4.9/x86-implement-array_index_mask_nospec.patch
queue-4.9/x86-alternative-print-unadorned-pointers.patch
queue-4.9/x86-cpuid-fix-up-virtual-ibrs-ibpb-stibp-feature-bits-on-intel.patch
queue-4.9/array_index_nospec-sanitize-speculative-array-de-references.patch
queue-4.9/kvm-vmx-make-indirect-call-speculation-safe.patch
queue-4.9/x86-cpufeatures-add-amd-feature-bits-for-speculation-control.patch
queue-4.9/x86-spectre-fix-spelling-mistake-vunerable-vulnerable.patch
queue-4.9/module-retpoline-warn-about-missing-retpoline-in-module.patch
queue-4.9/x86-kvm-update-spectre-v1-mitigation.patch
queue-4.9/x86-get_user-use-pointer-masking-to-limit-speculation.patch
queue-4.9/x86-syscall-sanitize-syscall-table-de-references-under-speculation.patch
queue-4.9/x86-spectre-simplify-spectre_v2-command-line-parsing.patch
queue-4.9/x86-msr-add-definitions-for-new-speculation-control-msrs.patch
queue-4.9/x86-pti-make-unpoison-of-pgd-for-trusted-boot-work-for-real.patch
queue-4.9/x86-pti-mark-constant-arrays-as-__initconst.patch
queue-4.9/x86-speculation-fix-typo-ibrs_att-which-should-be-ibrs_all.patch
queue-4.9/kaiser-fix-intel_bts-perf-crashes.patch
queue-4.9/x86-spectre-report-get_user-mitigation-for-spectre_v1.patch
queue-4.9/x86-introduce-barrier_nospec.patch
queue-4.9/kvm-vmx-emulate-msr_ia32_arch_capabilities.patch
queue-4.9/x86-bugs-drop-one-mitigation-from-dmesg.patch
queue-4.9/x86-retpoline-remove-the-esp-rsp-thunk.patch
queue-4.9/x86-pti-do-not-enable-pti-on-cpus-which-are-not-vulnerable-to-meltdown.patch
queue-4.9/x86-introduce-__uaccess_begin_nospec-and-uaccess_try_nospec.patch
queue-4.9/nl80211-sanitize-array-index-in-parse_txq_params.patch