[PATCH v2] powercap, intel_rapl.c, fix BIOS lock check

* [PATCH v2] powercap, intel_rapl.c, fix BIOS lock check
@ 2015-12-09 13:31 Prarit Bhargava
  2015-12-09 16:53 ` Jacob Pan
  0 siblings, 1 reply; 7+ messages in thread
From: Prarit Bhargava @ 2015-12-09 13:31 UTC (permalink / raw)
  To: linux-kernel
  Cc: Prarit Bhargava, Rafael J. Wysocki, Jacob Pan,
	Radivoje Jovanovic, Seiichi Ikarashi, Mathias Krause,
	Ajay Thomas

Intel RAPL initialized on several systems where the BIOS lock bit (msr
0x610, bit 63) was set.  This occured because the return value of
rapl_read_data_raw() was being checked, rather than the value of the variable
passed in, locked.

This patch properly implments the rapl_read_data_raw() call to check the
variable locked, and now the Intel RAPL driver outputs the warning:

	intel_rapl: RAPL package 0 domain package locked by BIOS

and does not initialize for the package.

Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Radivoje Jovanovic <radivoje.jovanovic@intel.com>
Cc: Seiichi Ikarashi <s.ikarashi@jp.fujitsu.com>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>

[v2]: fix brackets
---
 drivers/powercap/intel_rapl.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c
index cc97f08..48747c2 100644
--- a/drivers/powercap/intel_rapl.c
+++ b/drivers/powercap/intel_rapl.c
@@ -1341,10 +1341,13 @@ static int rapl_detect_domains(struct rapl_package *rp, int cpu)
 
 	for (rd = rp->domains; rd < rp->domains + rp->nr_domains; rd++) {
 		/* check if the domain is locked by BIOS */
-		if (rapl_read_data_raw(rd, FW_LOCK, false, &locked)) {
+		ret = rapl_read_data_raw(rd, FW_LOCK, false, &locked);
+		if (ret)
+			return ret;
+		if (locked) {
 			pr_info("RAPL package %d domain %s locked by BIOS\n",
 				rp->id, rd->name);
-				rd->state |= DOMAIN_STATE_BIOS_LOCKED;
+			rd->state |= DOMAIN_STATE_BIOS_LOCKED;
 		}
 	}
 
-- 
1.7.9.3


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