From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <1350367235.32704.1.camel@concordia> Subject: Re: [PATCH] kvm/powerpc: Handle errors in secondary thread grabbing From: Michael Ellerman To: Paul Mackerras Date: Tue, 16 Oct 2012 17:00:35 +1100 In-Reply-To: <20121016031352.GK1218@drongo> References: <1350346550-32539-1-git-send-email-michael@ellerman.id.au> <20121016031352.GK1218@drongo> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, agraf@suse.de, kvm-ppc@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2012-10-16 at 14:13 +1100, Paul Mackerras wrote: > Michael, > > On Tue, Oct 16, 2012 at 11:15:50AM +1100, Michael Ellerman wrote: > > In the Book3s HV code, kvmppc_run_core() has logic to grab the secondary > > threads of the physical core. > > > > If for some reason a thread is stuck, kvmppc_grab_hwthread() can fail, > > but currently we ignore the failure and continue into the guest. If the > > stuck thread is in the kernel badness ensues. > > > > Instead we should check for failure and bail out. > > > > I've moved the grabbing prior to the startup of runnable threads, to simplify > > the error case. AFAICS this is harmless, but I could be missing something > > subtle. > > Thanks for looking at this - but in fact this is fixed by my patch > entitled "KVM: PPC: Book3S HV: Fix some races in starting secondary > threads" submitted back on August 28. OK thanks. It seems that patch didn't make 3.7 ? I don't see it in kvm-ppc-next either. cheers