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

From: Prarit Bhargava
Date: Wed Dec 09 2015 - 08:31:20 EST


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@xxxxxxxxx>
Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Radivoje Jovanovic <radivoje.jovanovic@xxxxxxxxx>
Cc: Seiichi Ikarashi <s.ikarashi@xxxxxxxxxxxxxx>
Cc: Mathias Krause <minipli@xxxxxxxxxxxxxx>
Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@xxxxxxxxx>
Signed-off-by: Prarit Bhargava <prarit@xxxxxxxxxx>

[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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