x86/cpufeatures: Add X86_BUG_SPECTRE_V[12]

commit 99c6fa25 upstream.

Add the bug bits for spectre v1/2 and force them unconditionally for all
cpus.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1515239374-23361-2-git-send-email-dwmw@amazon.co.ukSigned-off-by: Razvan Ghitulete <rga@amazon.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/x86/include/asm/cpufeature.h

@@ -278,6 +278,8 @@
 #define X86_BUG_CLFLUSH_MONITOR	X86_BUG(7) /* AAI65, CLFLUSH required before MONITOR */
 #define X86_BUG_SYSRET_SS_ATTRS	X86_BUG(8) /* SYSRET doesn't fix up SS attrs */
 #define X86_BUG_CPU_MELTDOWN	X86_BUG(14) /* CPU is affected by meltdown attack and needs kernel page table isolation */
+#define X86_BUG_SPECTRE_V1	X86_BUG(15) /* CPU is affected by Spectre variant 1 attack with conditional branches */
+#define X86_BUG_SPECTRE_V2	X86_BUG(16) /* CPU is affected by Spectre variant 2 attack with indirect branches */
 
 #if defined(__KERNEL__) && !defined(__ASSEMBLY__)
 

arch/x86/kernel/cpu/common.c

@@ -834,6 +834,9 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
 	/* Assume for now that ALL x86 CPUs are insecure */
 	setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
 
+	setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
+	setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
+
 	fpu__init_system(c);
 }