Patch "intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()" has been added to the 4.4-stable tree

Patch "intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     intel_pstate-fix-msr_config_tdp_x-addressing-in-core_get_max_pstate.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 5fc8f707a2aa40c767c3a338738b9b6fcd151ac1 Mon Sep 17 00:00:00 2001
From: Jan Kiszka <jan.kiszka@siemens.com>
Date: Fri, 8 Jul 2016 20:42:04 +0200
Subject: intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()

From: Jan Kiszka <jan.kiszka@siemens.com>

commit 5fc8f707a2aa40c767c3a338738b9b6fcd151ac1 upstream.

If MSR_CONFIG_TDP_CONTROL is locked, we currently try to address some
MSR 0x80000648 or so. Mask out the relevant level bits 0 and 1.

Found while running over the Jailhouse hypervisor which became upset
about this strange MSR index.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/cpufreq/intel_pstate.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -662,7 +662,7 @@ static int core_get_max_pstate(void)
 			if (err)
 				goto skip_tar;
 
-			tdp_msr = MSR_CONFIG_TDP_NOMINAL + tdp_ctrl;
+			tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x3);
 			err = rdmsrl_safe(tdp_msr, &tdp_ratio);
 			if (err)
 				goto skip_tar;


Patches currently in stable-queue which might be from jan.kiszka@siemens.com are

queue-4.4/intel_pstate-fix-msr_config_tdp_x-addressing-in-core_get_max_pstate.patch