4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Len Brown <len.brown@xxxxxxxxx>
commit a4c447533a18ee86e07232d6344ba12b1f9c5077 upstream.
When MWAIT is disabled, intel_idle refuses to probe.
But it may mis-lead the user by blaming this on the model number:
intel_idle: does not run on family 6 modesl 79
So defer the check for MWAIT until after the model# white-list check succeeds,
and if the MWAIT check fails, tell the user how to fix it:
intel_idle: Please enable MWAIT in BIOS SETUP
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: Eduardo Valentin <eduval@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/idle/intel_idle.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1061,7 +1061,7 @@ static const struct idle_cpu idle_cpu_dn
};
#define ICPU(model, cpu) \
- { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu }
+ { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&cpu }
static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(INTEL_FAM6_NEHALEM_EP, idle_cpu_nehalem),
@@ -1125,6 +1125,11 @@ static int __init intel_idle_probe(void)
return -ENODEV;
}
+ if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
+ pr_debug("Please enable MWAIT in BIOS SETUP\n");
+ return -ENODEV;
+ }
+
if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
return -ENODEV;
