From mboxrd@z Thu Jan 1 00:00:00 1970 From: Suravee Suthikulanit Subject: Re: Time Skewing on Windows XP Date: Thu, 14 Mar 2013 11:38:10 -0500 Message-ID: <5141FCF2.4050800@amd.com> References: <513EB1BC.9050803@amd.com> <513EEF5102000078000C4C89@nat28.tlf.novell.com> <5141E9CB.9020608@amd.com> <514203A502000078000C59E2@nat28.tlf.novell.com> <5141F90F.6060408@amd.com> <51420A3902000078000C5A28@nat28.tlf.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51420A3902000078000C5A28@nat28.tlf.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich Cc: George.Dunlap@eu.citrix.com, "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org On 3/14/2013 11:34 AM, Jan Beulich wrote: >>>> On 14.03.13 at 17:21, Suravee Suthikulanit wrote: >> On 3/14/2013 11:06 AM, Jan Beulich wrote: >>>>>> On 14.03.13 at 16:16, Suravee Suthikulanit wrote: >>>> I finally traced the issue back to the patch that this first happened. This >>>> bug started in the patch : >>>> >>>> H86/HVM: assorted RTC emulation adjustment (w/ git commit id >>>> 620d5dad54008e40798c4a0c4322aef274c36fa3) >>>> >>>> I believe there are some issues with the changes in rtc_ioport_read in the >>>> arch/x86/hvm/rtc.c and in the pt_update_irq(). >>> One thing you may want to try is remove the call from REG_C >>> read to rtc_timer_update() again - on a second thought it may >>> be wrong to do it here, as (other than check_update_timer() >>> and alarm_timer_update()) the function doesn't change with >>> RTC_PF getting cleared (i.e. I may have wrongly added the call >>> in analogy to the other two). >> If I do the followings, things start working again: >> 1. remove the rtc_timer_update() in the rtc_ioport_read() >> 2. Revert back the "rtc_periodic_cb()" and remove the >> "rtc_periodic_interrupt()" >> >> What was the purpose of changing the "rtc_periodic_cb()" to >> "rtc_periodic_interrupt()" ? > The main point was to be able to call rtc_toggle_irq() from that > function (to get RTC_IRQF properly set), instead of > pt_update_irq() doing only the IRQ deassert/assert pair. > > So removing just the questionable call to rtc_timer_update() > doesn't help? > > Jan Removing just the call to "rtc_timer_update" causes XP failed to boot and hanged. It seems like it did not get the right timer interrupt it was looking for. Suravee > >