https://bugzilla.kernel.org/show_bug.cgi?id=55411 --- Comment #22 from Thomas Renninger <trenn@xxxxxxx> 2013-03-22 14:04:09 --- On Friday, March 22, 2013 07:13:33 PM Viresh Kumar wrote: > Hi guys, > > I will answer to questions of both of you in this mail. > > On 22 March 2013 18:23, Thomas Renninger <trenn@xxxxxxx> wrote: > > Is this all to try to fix "cpufreq driver gets loaded while some cores > > were set offline before"? > > Not really. There are problems with acpi-cpufreq without that case too. > > > I wonder how you run into "cpufreq is initialized with offlined cpus" > > case. > > I remember that there were problems, but it's nearly impossible to run > > into this if the cpufreq driver is loaded early at boot. > > I always thought there is a way not to boot all cpus by passing stuff in > command line and so this is a easy case to reproduce. I am pretty sure cpuidle states won't initialize and in best case you never get them working on the offlined cpus. Local APICs won't be set up, ... Such a parameter will never exist for x86. > > cpufreq_add_dev() and friends are complicated. > > Not anymore, they are hugely simplified now. They were hugely simplified and things are not working anymore and you do not know why... > > Those init functions got split some time ago and there also slipped > > in a bug even it was simple splitting of functions. > > > > I do not have time to look at fcf8058296edbc3de43adf095824fc32b067b9f8 > > right now. Don't know how much other stuff depends on it and how > > sever it is on ARM that cpufreq does not correctly initialize with > > offlined > > cpus..., I would revert this patch. > > Let me clear it to everybody. There isn't/shouldn't be a bug in cpufreq > core, its just that acpi-cpufreq driver isn't adapted well with the changes > related to affected_cpus and related_cpus. And powernow-k8 driver is broken. The others are not tested that often, I expect they broke as well, right? > I have never gone into coding for any non-ARM platform and am really not > aware of acpi-cpufreq driver and its users. That's why i told everybody > where the issue is, and they just need to fix acpi-cpufreq driver with > right values of policy->cpus (affected_cpus) and everything else would work > after that. Sorry, I cannot look into this due to lack of time, but I remember that there were reasons why cpufreq_add_dev() was complicated. Or that it's really easy to mess it up and it's not easy to fix it again. Thomas -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug. -- 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
