From mboxrd@z Thu Jan 1 00:00:00 1970 From: Razvan Cojocaru Subject: Re: [PATCH] vm_event: consolidate hvm_event_fill_regs and p2m_vm_event_fill_regs Date: Thu, 11 Feb 2016 23:49:32 +0200 Message-ID: <56BD01EC.5090202@bitdefender.com> References: <1455224749-2120-1-git-send-email-tlengyel@novetta.com> <56BCFEAE.8070608@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aTz7J-0000dY-4w for xen-devel@lists.xenproject.org; Thu, 11 Feb 2016 21:49:37 +0000 Received: from smtp01.buh.bitdefender.com (unknown [10.17.80.75]) by mx-sr.buh.bitdefender.com (Postfix) with ESMTP id 15DC97FBDC for ; Thu, 11 Feb 2016 23:49:34 +0200 (EET) In-Reply-To: <56BCFEAE.8070608@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andrew Cooper , Tamas K Lengyel , xen-devel@lists.xenproject.org Cc: George Dunlap , Keir Fraser , Jan Beulich List-Id: xen-devel@lists.xenproject.org On 02/11/2016 11:35 PM, Andrew Cooper wrote: > On 11/02/2016 21:05, Tamas K Lengyel wrote: > >> diff --git a/xen/arch/x86/vm_event.c b/xen/arch/x86/vm_event.c >> index 08d678a..fa5d154 100644 >> --- a/xen/arch/x86/vm_event.c >> +++ b/xen/arch/x86/vm_event.c >> @@ -122,6 +122,64 @@ void vm_event_set_registers(struct vcpu *v, vm_event_response_t *rsp) >> v->arch.user_regs.eip = rsp->data.regs.x86.rip; >> } >> >> +void vm_event_fill_regs(vm_event_request_t *req) >> +{ >> + const struct cpu_user_regs *regs = guest_cpu_user_regs(); >> + struct segment_register seg; >> + struct hvm_hw_cpu ctxt; >> + struct vcpu *curr = current; >> + >> + req->data.regs.x86.rax = regs->eax; >> + req->data.regs.x86.rcx = regs->ecx; >> + req->data.regs.x86.rdx = regs->edx; >> + req->data.regs.x86.rbx = regs->ebx; >> + req->data.regs.x86.rsp = regs->esp; >> + req->data.regs.x86.rbp = regs->ebp; >> + req->data.regs.x86.rsi = regs->esi; >> + req->data.regs.x86.rdi = regs->edi; >> + >> + req->data.regs.x86.r8 = regs->r8; >> + req->data.regs.x86.r9 = regs->r9; >> + req->data.regs.x86.r10 = regs->r10; >> + req->data.regs.x86.r11 = regs->r11; >> + req->data.regs.x86.r12 = regs->r12; >> + req->data.regs.x86.r13 = regs->r13; >> + req->data.regs.x86.r14 = regs->r14; >> + req->data.regs.x86.r15 = regs->r15; >> + >> + req->data.regs.x86.rflags = regs->eflags; >> + req->data.regs.x86.rip = regs->eip; >> + req->data.regs.x86.dr7 = curr->arch.debugreg[7]; > > I think there is a %dr7 handling issue here. For an HVM guests, this > field is only valid when you are not in the context of the guest, as it > lives in the vmcs/vmcs. (PV guests keep it synchronously up to date) Would this make it OK to use in p2m_vm_event_fill_regs() but not in hvm_event_fill_regs(), as it currently is? Maybe this is the issue I'm remembering. Thanks, Razvan