x86/mce/mce-inject: Preset the MCE injection struct

Populate the MCE injection struct before doing initial injection so that
values which don't change have sane defaults.

Tested-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20170613162835.30750-7-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/mcheck/mce-inject.c

@@ -103,6 +103,13 @@ DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n");
 DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n");
 DEFINE_SIMPLE_ATTRIBUTE(synd_fops, inj_synd_get, inj_synd_set, "%llx\n");
 
+static void setup_inj_struct(struct mce *m)
+{
+	memset(m, 0, sizeof(struct mce));
+
+	m->cpuvendor = boot_cpu_data.x86_vendor;
+}
+
 /* Update fake mce registers on current CPU. */
 static void inject_mce(struct mce *m)
 {
@@ -700,6 +707,8 @@ static int __init inject_init(void)
 	register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify");
 	mce_register_injector_chain(&inject_nb);
 
+	setup_inj_struct(&i_mce);
+
 	pr_info("Machine check injector initialized\n");
 
 	return 0;