Hi, Boris, thanks for you reply > -----Original Message----- > From: Borislav Petkov [mailto:b...@suse.de] > Sent: Tuesday, October 13, 2015 12:38 AM > To: Chen, Yu C > Cc: mi...@redhat.com; r...@rjwysocki.net; pa...@ucw.cz; > t...@linutronix.de; h...@zytor.com; Zhang, Rui; l...@kernel.org; > li...@horizon.com; dsmyth...@telus.net; linux...@vger.kernel.org; > x...@kernel.org; linux-kernel@vger.kernel.org; Kaszewski, Marcin > Subject: Re: [PATCH][v5] x86, suspend: Save/restore extra MSR registers for > suspend > > On Sun, Oct 11, 2015 at 11:20:01AM +0800, Chen Yu wrote: > > A bug is reported(https://bugzilla.redhat.com/show_bug.cgi?id=1227208) > > I get: > > "You are not authorized to access bug #1227208. > > Most likely the bug has been restricted for internal development processes > and we cannot grant access." > > > that, after resumed from S3, CPU is running at a low speed. > > After investigation, it is found that, BIOS has modified the value of > > THERM_CONTROL register during S3, and changes it from 0 to 0x10 (thus > > changes the clock modulation from reserved to enabled), since value of > > 0x10 means CPU can only get 25% of the Duty Cycle, this triggers the > > problem. > > Is this what the bug described above is? In any case, please remove the > private bugzilla link and describe the bug in text here. OK, will remove the link here and inside the code. > > Also, from reading the other thread about the v4 patch, it sounds like > intel_pstate can't handle the clock modulation properly, according to what > Doug says. > > So let's have this aspect sorted out properly first please before adding yet > another ugly BIOS workaround. > Well, that might be another driver bug IMO. I'll dig into that one.
> Btw, why can't that BIOS be fixed instead? This bug is found on a released redhat server, so I think it would be hard to update all users' machines. > > -- > Regards/Gruss, > Boris. Best Regards, Yu
