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

[Prarit Bhargava]

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...@intel.com>
Cc: Jacob Pan <jacob....@linux.intel.com>
Cc: Radivoje Jovanovic <radivoje....@intel.com>
Cc: Seiichi Ikarashi <s.ika...@jp.fujitsu.com>
Cc: Mathias Krause <min...@googlemail.com>
Cc: Ajay Thomas <ajay.thomas.dav...@intel.com>
Signed-off-by: Prarit Bhargava <pra...@redhat.com>
---
drivers/powercap/intel_rapl.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c
index cc97f08..0b0d09d 100644
--- a/drivers/powercap/intel_rapl.c
+++ b/drivers/powercap/intel_rapl.c
@@ -1341,11 +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;
- }
}


--
1.7.9.3

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[Jacob Pan]

On Tue, 8 Dec 2015 13:33:22 -0500
Prarit Bhargava <pra...@redhat.com> wrote:

> 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.

Looks good to me.

[Seiichi Ikarashi]

A good spot!
But this patch looks setting DOMAIN_STATE_BIOS_LOCKED bit to all package domains.
I suppose what you are going to do is like below.

--- a/drivers/powercap/intel_rapl.c 2015-11-02 09:05:25.000000000 +0900
+++ b/drivers/powercap/intel_rapl.c 2015-12-09 09:05:33.386142840 +0900
@@ -1340,10 +1340,13 @@ static int rapl_detect_domains(struct ra

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;

[Prarit Bhargava]

Oh geez :) Of course ... I'll resubmit shortly.

P.

[Prarit Bhargava]

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...@intel.com>
Cc: Jacob Pan <jacob....@linux.intel.com>
Cc: Radivoje Jovanovic <radivoje....@intel.com>
Cc: Seiichi Ikarashi <s.ika...@jp.fujitsu.com>
Cc: Mathias Krause <min...@googlemail.com>
Cc: Ajay Thomas <ajay.thomas.dav...@intel.com>
Signed-off-by: Prarit Bhargava <pra...@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

[Jacob Pan]

On Wed, 9 Dec 2015 08:31:12 -0500
Prarit Bhargava <pra...@redhat.com> wrote:

> 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...@intel.com>
> Cc: Jacob Pan <jacob....@linux.intel.com>
> Cc: Radivoje Jovanovic <radivoje....@intel.com>
> Cc: Seiichi Ikarashi <s.ika...@jp.fujitsu.com>
> Cc: Mathias Krause <min...@googlemail.com>
> Cc: Ajay Thomas <ajay.thomas.dav...@intel.com>
> Signed-off-by: Prarit Bhargava <pra...@redhat.com>
>
> [v2]: fix brackets

Acked-by: Jacob Pan <jacob....@linux.intel.com>

Good catch by Seiichi, thanks.

[Rafael J. Wysocki]

On Wednesday, December 09, 2015 08:53:55 AM Jacob Pan wrote:
> On Wed, 9 Dec 2015 08:31:12 -0500
> Prarit Bhargava <pra...@redhat.com> wrote:
>
> > 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...@intel.com>
> > Cc: Jacob Pan <jacob....@linux.intel.com>
> > Cc: Radivoje Jovanovic <radivoje....@intel.com>
> > Cc: Seiichi Ikarashi <s.ika...@jp.fujitsu.com>
> > Cc: Mathias Krause <min...@googlemail.com>
> > Cc: Ajay Thomas <ajay.thomas.dav...@intel.com>
> > Signed-off-by: Prarit Bhargava <pra...@redhat.com>
> >
> > [v2]: fix brackets
>
> Acked-by: Jacob Pan <jacob....@linux.intel.com>

OK, I've put it into my bleeding-edge branch as 4.5 candidate, but do we
want it in "stable" and therefore should it be pushed for 4.4?

Thanks,
Rafael

[Jacob Pan]

On Thu, 10 Dec 2015 00:38:27 +0100
"Rafael J. Wysocki" <r...@rjwysocki.net> wrote:

> OK, I've put it into my bleeding-edge branch as 4.5 candidate, but do
> we want it in "stable" and therefore should it be pushed for 4.4?

yes, it is a bug fix that may affect many systems locked by BIOS.

[Rafael J. Wysocki]

On Wednesday, December 09, 2015 03:31:23 PM Jacob Pan wrote:
> On Thu, 10 Dec 2015 00:38:27 +0100
> "Rafael J. Wysocki" <r...@rjwysocki.net> wrote:
>
> > OK, I've put it into my bleeding-edge branch as 4.5 candidate, but do
> > we want it in "stable" and therefore should it be pushed for 4.4?
> yes, it is a bug fix that may affect many systems locked by BIOS.

So which "stable" series in particular should it go to? All applicable?

Thanks,
Rafael

[Prarit Bhargava]

On 12/09/2015 07:52 PM, Rafael J. Wysocki wrote:
> On Wednesday, December 09, 2015 03:31:23 PM Jacob Pan wrote:
>> On Thu, 10 Dec 2015 00:38:27 +0100
>> "Rafael J. Wysocki" <r...@rjwysocki.net> wrote:
>>
>>> OK, I've put it into my bleeding-edge branch as 4.5 candidate, but do
>>> we want it in "stable" and therefore should it be pushed for 4.4?
>> yes, it is a bug fix that may affect many systems locked by BIOS.
>
> So which "stable" series in particular should it go to? All applicable?
>

Yes, all applicable IMO.

P.

[Jacob Pan]

On Thu, 10 Dec 2015 01:52:37 +0100
"Rafael J. Wysocki" <r...@rjwysocki.net> wrote:

> So which "stable" series in particular should it go to? All
> applicable?

yes. rapl is there since SNB, quite some time.