From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41082) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cm4M5-0000vM-Ha for qemu-devel@nongnu.org; Thu, 09 Mar 2017 15:08:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cm4M1-0007Zq-J6 for qemu-devel@nongnu.org; Thu, 09 Mar 2017 15:08:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47792) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cm4M1-0007Yb-De for qemu-devel@nongnu.org; Thu, 09 Mar 2017 15:08:05 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6343085547 for ; Thu, 9 Mar 2017 20:08:05 +0000 (UTC) Date: Thu, 9 Mar 2017 20:08:00 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20170309200759.GP2480@work-vm> References: <20170309194634.28457-1-ehabkost@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170309194634.28457-1-ehabkost@redhat.com> Subject: Re: [Qemu-devel] [PATCH for-2.10 v2] kvm: Print MSR information if KVM_{GET, SET}_MSRS failed List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eduardo Habkost Cc: qemu-devel@nongnu.org, Paolo Bonzini * Eduardo Habkost (ehabkost@redhat.com) wrote: > When a KVM_{GET,SET}_MSRS ioctl() fails, it is difficult to find > out which MSR caused the problem. Print an error message for > debugging, before we trigger the (ret == cpu->kvm_msr_buf->nmsrs) > assert. > > Suggested-by: Dr. David Alan Gilbert > Signed-off-by: Eduardo Habkost Thanks! Reviewed-by: Dr. David Alan Gilbert I'd actually suggest it for 2.9; it's only added debug output. Dave > --- > Changes v1 -> v2: > * Print error message on KVM_GET_MSRS too > * Suggested-by: Dr. David Alan Gilbert > --- > target/i386/kvm.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/target/i386/kvm.c b/target/i386/kvm.c > index 887a81268f..705e971a63 100644 > --- a/target/i386/kvm.c > +++ b/target/i386/kvm.c > @@ -1807,6 +1807,12 @@ static int kvm_put_msrs(X86CPU *cpu, int level) > return ret; > } > > + if (ret < cpu->kvm_msr_buf->nmsrs) { > + struct kvm_msr_entry *e = &cpu->kvm_msr_buf->entries[ret]; > + error_report("error: failed to set MSR 0x%" PRIx32 " to 0x%" PRIx64, > + (uint32_t)e->index, (uint64_t)e->data); > + } > + > assert(ret == cpu->kvm_msr_buf->nmsrs); > return 0; > } > @@ -2172,6 +2178,12 @@ static int kvm_get_msrs(X86CPU *cpu) > return ret; > } > > + if (ret < cpu->kvm_msr_buf->nmsrs) { > + struct kvm_msr_entry *e = &cpu->kvm_msr_buf->entries[ret]; > + error_report("error: failed to get MSR 0x%" PRIx32, > + (uint32_t)e->index); > + } > + > assert(ret == cpu->kvm_msr_buf->nmsrs); > /* > * MTRR masks: Each mask consists of 5 parts > -- > 2.11.0.259.g40922b1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK