From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Renninger Subject: Re: [PATCH]: cpufreq: pcc-cpufreq: don't load driver if get_freq fails during init. Date: Wed, 9 Mar 2011 17:09:40 +0100 Message-ID: <201103091709.40464.trenn@suse.de> References: <20110309135906.6554.54389.sendpatchset@nchumbalkar.americas.hpqcorp.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110309135906.6554.54389.sendpatchset@nchumbalkar.americas.hpqcorp.net> Sender: linux-acpi-owner@vger.kernel.org List-ID: Content-Type: Text/Plain; charset="us-ascii" To: Naga Chumbalkar Cc: Dave Jones , linux-acpi@vger.kernel.org, cpufreq@vger.kernel.org, Greg Kroah-Hartman Good catch. On Wednesday, March 09, 2011 03:02:49 PM Naga Chumbalkar wrote: > > Return 0 on failure. This will cause the initialization of the driver > to fail and prevent the driver from loading if the BIOS cannot handle > the PCC interface command to "get frequency". Otherwise, the driver > will load and display a very high value like "4294967274" (which is > actually -EINVAL) for frequency: > > # cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq > 4294967274 > > Signed-off-by: Naga Chumbalkar Reviewed-by: Thomas Renninger While this is not a regression, it's an easy fix. It should make sense to add: CC: stable@kernel.org ? Thomas > --- > > diff --git a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c > index 4f6f679..4a5a42b 100644 > --- a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c > +++ b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c > @@ -195,7 +195,7 @@ static unsigned int pcc_get_freq(unsigned int cpu) > cmd_incomplete: > iowrite16(0, &pcch_hdr->status); > spin_unlock(&pcc_lock); > - return -EINVAL; > + return 0; > } > > static int pcc_cpufreq_target(struct cpufreq_policy *policy, > -- > To unsubscribe from this list: send the line "unsubscribe cpufreq" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >