linux-kernel - [PATCH 4.8 022/138] thermal/powerclamp: correct cpu support check

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Message-Id: <20161109102845.758765195@linuxfoundation.org>
Date:   Wed,  9 Nov 2016 11:45:05 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Eric Ernst <eric.ernst@...ux.intel.com>,
        Jacob Pan <jacob.jun.pan@...ux.intel.com>,
        Zhang Rui <rui.zhang@...el.com>
Subject: [PATCH 4.8 022/138] thermal/powerclamp: correct cpu support check

4.8-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Ernst <eric.ernst@...ux.intel.com>

commit 3105f234e0aba43e44e277c20f9b32ee8add43d4 upstream.

Initial logic for checking CPU match resulted in OR of CPU features
rather than the intended AND.

Updated to use boot_cpu_has macro rather than x86_match_cpu.

In addition, MWAIT is the only required CPU feature for idle
injection to work.  Drop other feature requirements since they are
only needed for optimal efficiency.

Signed-off-by: Eric Ernst <eric.ernst@...ux.intel.com>
Acked-by: Jacob Pan <jacob.jun.pan@...ux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@...el.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/thermal/intel_powerclamp.c |   14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

--- a/drivers/thermal/intel_powerclamp.c
+++ b/drivers/thermal/intel_powerclamp.c
@@ -669,20 +669,10 @@ static struct thermal_cooling_device_ops
 	.set_cur_state = powerclamp_set_cur_state,
 };
 
-static const struct x86_cpu_id intel_powerclamp_ids[] __initconst = {
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_MWAIT },
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_ARAT },
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_NONSTOP_TSC },
-	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_CONSTANT_TSC},
-	{}
-};
-MODULE_DEVICE_TABLE(x86cpu, intel_powerclamp_ids);
-
 static int __init powerclamp_probe(void)
 {
-	if (!x86_match_cpu(intel_powerclamp_ids)) {
-		pr_err("Intel powerclamp does not run on family %d model %d\n",
-				boot_cpu_data.x86, boot_cpu_data.x86_model);
+	if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
+		pr_err("CPU does not support MWAIT");
 		return -ENODEV;
 	}