On Thursday, March 21, 2013 01:08:03 AM Rafael J. Wysocki wrote: > On Wednesday, March 20, 2013 11:28:49 AM Dirk Brandewie wrote: > > On 03/20/2013 11:28 AM, Rafael J. Wysocki wrote: > > > On Wednesday, March 20, 2013 09:17:24 AM dirk.brandewie@xxxxxxxxx wrote: > > >> From: Dirk Brandewie <dirk.brandewie@xxxxxxxxx> > > >> > > >> Some VMs seem to try to implement some MSRs but not all the registers > > >> the driver needs. Check to make sure all the MSR that we need are > > >> available. If any of the required MSRs are not available refuse to > > >> load. > > >> > > >> Signed-off-by: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx> > > > > > > Is this needed for v3.9? Any pointers to bug reports etc.? > > > > > > > Sorry I saw right after I sent the mail that the bug report was missing > > > > https://bugzilla.redhat.com/show_bug.cgi?id=922923 > > Reported-by: Josh Stone <jistone@xxxxxxxxxx> > > > > Would you like me to spin the patch? > > No, thanks, this information is sufficient. Applied to linux-pm.git/bleeding-edge and will be moved to linux-next after build testing. Thanks, Rafael > > >> --- > > >> drivers/cpufreq/intel_pstate.c | 26 ++++++++++++++++++++++++++ > > >> 1 files changed, 26 insertions(+), 0 deletions(-) > > >> > > >> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > > >> index f6dd1e7..cd9c5f4 100644 > > >> --- a/drivers/cpufreq/intel_pstate.c > > >> +++ b/drivers/cpufreq/intel_pstate.c > > >> @@ -752,6 +752,29 @@ static struct cpufreq_driver intel_pstate_driver = { > > >> > > >> static int __initdata no_load; > > >> > > >> +static int intel_pstate_msrs_not_valid(void) > > >> +{ > > >> + /* Check that all the msr's we are using are valid. */ > > >> + u64 aperf, mperf, tmp; > > >> + > > >> + rdmsrl(MSR_IA32_APERF, aperf); > > >> + rdmsrl(MSR_IA32_MPERF, mperf); > > >> + > > >> + if (!intel_pstate_min_pstate() || > > >> + !intel_pstate_max_pstate() || > > >> + !intel_pstate_turbo_pstate()) > > >> + return -ENODEV; > > >> + > > >> + rdmsrl(MSR_IA32_APERF, tmp); > > >> + if (!(tmp - aperf)) > > >> + return -ENODEV; > > >> + > > >> + rdmsrl(MSR_IA32_MPERF, tmp); > > >> + if (!(tmp - mperf)) > > >> + return -ENODEV; > > >> + > > >> + return 0; > > >> +} > > >> static int __init intel_pstate_init(void) > > >> { > > >> int cpu, rc = 0; > > >> @@ -764,6 +787,9 @@ static int __init intel_pstate_init(void) > > >> if (!id) > > >> return -ENODEV; > > >> > > >> + if (intel_pstate_msrs_not_valid()) > > >> + return -ENODEV; > > >> + > > >> pr_info("Intel P-state driver initializing.\n"); > > >> > > >> all_cpu_data = vmalloc(sizeof(void *) * num_possible_cpus()); > > >> > > > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
