Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753616AbaBDIDb (ORCPT ); Tue, 4 Feb 2014 03:03:31 -0500 Received: from mail-pa0-f47.google.com ([209.85.220.47]:59877 "EHLO mail-pa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753305AbaBDIDV (ORCPT ); Tue, 4 Feb 2014 03:03:21 -0500 Message-ID: <52F09EC0.60201@ozlabs.ru> Date: Tue, 04 Feb 2014 19:03:12 +1100 From: Alexey Kardashevskiy User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Alexander Graf CC: linuxppc-dev@lists.ozlabs.org, Paul Mackerras , kvm-ppc@vger.kernel.org, "kvm@vger.kernel.org mailing list" , "linux-kernel@vger.kernel.org list" Subject: Re: [PATCH] PPC: KVM: fix VCPU run for HV KVM References: <1389338467-26303-1-git-send-email-aik@ozlabs.ru> In-Reply-To: Content-Type: text/plain; charset=KOI8-R Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/13/2014 02:44 AM, Alexander Graf wrote: > > On 10.01.2014, at 08:21, Alexey Kardashevskiy wrote: > >> When write to MMIO happens and there is an ioeventfd for that and >> is handled successfully, ioeventfd_write() returns 0 (success) and >> kvmppc_handle_store() returns EMULATE_DONE. Then kvmppc_emulate_mmio() >> converts EMULATE_DONE to RESUME_GUEST_NV and this broke from the loop. >> >> This adds handling of RESUME_GUEST_NV in kvmppc_vcpu_run_hv(). >> >> Cc: Michael S. Tsirkin >> Suggested-by: Paul Mackerras >> Signed-off-by: Alexey Kardashevskiy >> --- >> >> This definitely needs a better commit message. Please, help. >> ps. it seems like ioeventfd never worked on ppc64. hm. >> >> --- >> arch/powerpc/kvm/book3s_hv.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c >> index 072287f..24f363f 100644 >> --- a/arch/powerpc/kvm/book3s_hv.c >> +++ b/arch/powerpc/kvm/book3s_hv.c >> @@ -1569,7 +1569,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) >> vcpu->arch.fault_dar, vcpu->arch.fault_dsisr); >> srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); >> } >> - } while (r == RESUME_GUEST); >> + } while ((r == RESUME_GUEST_NV) || (r == RESUME_GUEST)); > > How about > > while(!(r & RESUME_FLAG_HOST)); Rather "while(!(r & RESUME_FLAG_HOST) && (r > 0));" and still not obvious that this is really better. Paul agrees with the original patch (and made a better commit message for our internal tree) but I just cannot make him reply in this thread, keep constantly asking him but to no avail :) > That should cover all RESUME_GUEST_XXX cases just fine. Apart from that > I agree that we should check for ! FLAG_HOST bit rather than the actual > RESUME_GUEST value in all case where we check for it (read: please > update all places). There are 3 places remotely similar to this and none of them requires a fix like above. -- Alexey -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/