From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hollis Blanchard Date: Thu, 20 Mar 2008 16:12:18 +0000 Subject: Re: [kvm-ppc-devel] guest panic fixed Message-Id: <1206029538.6356.3.camel@basalt> List-Id: References: <1205969120.11366.67.camel@basalt> In-Reply-To: <1205969120.11366.67.camel@basalt> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ppc@vger.kernel.org On Thu, 2008-03-20 at 09:32 +0100, Christian Ehrhardt wrote: > Hollis Blanchard wrote: > > Thanks to some excellent debugging by Christian, we found the cause of > > our annoying guest panics. We had not implemented exception priorities > > (my bad), so a userspace ITLB miss was being delivered immediately after > > entry to the decrementer interrupt vector. Patch follows, > > http://penguinppc.org/~hollisb/kvm/ updated. > > > > NFS root with virtio-net still doesn't work for me, but it doesn't > > crash. :) > > > > @@ -65,12 +68,14 @@ extern void kvmppc_44x_tlb_trace(int act > > > > static inline void kvmppc_queue_exception(struct kvm_vcpu *vcpu, int exception) > > { > > - set_bit(exception, &vcpu->arch.pending_exceptions); > > + unsigned int priority = exception_priority[exception]; > > + set_bit(priority, &vcpu->arch.pending_exceptions); > > saves a line and a local var on irq path (well the compiler might optimize that anyway) > set_bit(exception_priority[exception], &vcpu->arch.pending_exceptions); The compiler should handle it; you can examine the disassembly if you're worried. -- Hollis Blanchard IBM Linux Technology Center ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-ppc-devel mailing list kvm-ppc-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-ppc-devel