From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: KVM Test result, kernel 873c05f.., userspace d102d75.. Date: Thu, 24 Apr 2008 16:21:00 +0300 Message-ID: <4810893C.2050101@qumranet.com> References: <48106140.9070600@intel.com> <481070DF.8070709@qumranet.com> <200804242059.44235.sheng.yang@intel.com> <48108466.2080707@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel@lists.sourceforge.net, Marcelo Tosatti To: "Yang, Sheng" Return-path: In-Reply-To: <48108466.2080707@qumranet.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net List-Id: kvm.vger.kernel.org Avi Kivity wrote: > Yang, Sheng wrote: >> On Thursday 24 April 2008 19:37:03 Avi Kivity wrote: >> >>> Yunfeng Zhao wrote: >>> >>>> Hi All, >>>> >>>> This is today's KVM test result against kvm.git >>>> 873c05fa7e6fea27090b1bf0f67a073eadb04782 and kvm-userspace.git >>>> d102d750f397b543fe620a3c77a7e5e42c483865. >>>> >>> I suspect 873c05fa7e6fea27090b1bf0f67a073eadb04782 itself, it's the >>> only >>> thing that has any chance of badness. >>> >>> Marcelo, any idea? Perhaps due to load, interrupts accumulate and >>> can't >>> be injected fast enough? >>> >>> These tests are run on a 2.6.22 host, which has a hacked >>> smp_call_function_single() in external-module-compat.h, which may >>> exaberate the problem. >>> >> >> Yeah, I suspect the commit too(I tried tip without that, and found >> mostly alright). In fact, I didn't use kvm_vcpu_kick() just because >> that I found this function may causing hang on my host... But I >> didn't do more investigate so I can't tell what's wrong, then I just >> chose way to keep it working... I am sorry for not clarify... >> > > I think smp_call_function_single() is miscompiled when using the > compatibility code. I took it out-of-line to be sure (it is now in > kernel/external-module-compat.c). > > No evidence, but... > Ok. __pit_timer_fn() is called from an interrupt, which then calls smp_call_function_single(), which calls spin_lock(). If we've already taken the lock, we hang. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone