x86/bugs: Concentrate bug detection into a separate function

Combine the various logic which goes through all those
x86_cpu_id matching structures in one function.

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index ce243f7..9ed0a18 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -927,21 +927,27 @@ static const __initconst struct x86_cpu_id cpu_no_meltdown[] = {
        {}
 };
 
-static bool __init cpu_vulnerable_to_meltdown(struct cpuinfo_x86 *c)
+static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
 {
        u64 ia32_cap = 0;
 
+       if (x86_match_cpu(cpu_no_speculation))
+               return;
+
+       setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
+       setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
+
        if (x86_match_cpu(cpu_no_meltdown))
-               return false;
+               return;
 
        if (cpu_has(c, X86_FEATURE_ARCH_CAPABILITIES))
                rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
 
        /* Rogue Data Cache Load? No! */
        if (ia32_cap & ARCH_CAP_RDCL_NO)
-               return false;
+               return;
 
-       return true;
+       setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
 }
 
 /*
@@ -992,12 +998,7 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
 
        setup_force_cpu_cap(X86_FEATURE_ALWAYS);
 
-       if (!x86_match_cpu(cpu_no_speculation)) {
-               if (cpu_vulnerable_to_meltdown(c))
-                       setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
-               setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
-               setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
-       }
+       cpu_set_bug_bits(c);
 
        fpu__init_system(c);