From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CF97C64E7A for ; Tue, 1 Dec 2020 11:38:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADD422084C for ; Tue, 1 Dec 2020 11:38:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hsWlzNo1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727779AbgLALil (ORCPT ); Tue, 1 Dec 2020 06:38:41 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:48317 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726765AbgLALik (ORCPT ); Tue, 1 Dec 2020 06:38:40 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606822633; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=mEg2mvzmDJQWmGL7PYMzg8O29/2xQkUxKTa922eJt3k=; b=hsWlzNo1xft9BvIzlLVXhufY16PubIlDWx23oDlcsoSeR47CRZ3Y7e6ACUDmq7Val6rSTO 2MBW/7p4kJxcZojND2PXar1p1HzTAfZuzySQlMg7aHlYYtEPz92hUuOnP7lNS81Wo+7AVI XcCD+NezxduwSVxp0Og+KlqTFG0GO5o= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-240-IFLTQ76fNu2YwhjvsgGOKQ-1; Tue, 01 Dec 2020 06:37:12 -0500 X-MC-Unique: IFLTQ76fNu2YwhjvsgGOKQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 111C780364B; Tue, 1 Dec 2020 11:37:11 +0000 (UTC) Received: from work-vm (ovpn-115-1.ams2.redhat.com [10.36.115.1]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 06679189CE; Tue, 1 Dec 2020 11:37:04 +0000 (UTC) Date: Tue, 1 Dec 2020 11:37:02 +0000 From: "Dr. David Alan Gilbert" To: Ashish Kalra Cc: pbonzini@redhat.com, qemu-devel@nongnu.org, rth@twiddle.net, armbru@redhat.com, ehabkost@redhat.com, kvm@vger.kernel.org, mst@redhat.com, marcel.apfelbaum@gmail.com, mtosatti@redhat.com, Thomas.Lendacky@amd.com, brijesh.singh@amd.com, ssg.sos.patches@amd.com Subject: Re: [PATCH 02/11] exec: Add new MemoryDebugOps. Message-ID: <20201201113702.GE4338@work-vm> References: <4393d426ae8f070c6be45ff0252bae2dca8bbd42.1605316268.git.ashish.kalra@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4393d426ae8f070c6be45ff0252bae2dca8bbd42.1605316268.git.ashish.kalra@amd.com> User-Agent: Mutt/1.14.6 (2020-07-11) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org * Ashish Kalra (Ashish.Kalra@amd.com) wrote: > From: Ashish Kalra > > Introduce new MemoryDebugOps which hook into guest virtual and physical > memory debug interfaces such as cpu_memory_rw_debug, to allow vendor specific > assist/hooks for debugging and delegating accessing the guest memory. > This is required for example in case of AMD SEV platform where the guest > memory is encrypted and a SEV specific debug assist/hook will be required > to access the guest memory. > > The MemoryDebugOps are used by cpu_memory_rw_debug() and default to > address_space_read and address_space_write_rom. > > Signed-off-by: Ashish Kalra Reviewed-by: Dr. David Alan Gilbert > --- > include/exec/memory.h | 11 +++++++++++ > softmmu/physmem.c | 24 ++++++++++++++++++++---- > 2 files changed, 31 insertions(+), 4 deletions(-) > > diff --git a/include/exec/memory.h b/include/exec/memory.h > index aff6ef7605..73deb4b456 100644 > --- a/include/exec/memory.h > +++ b/include/exec/memory.h > @@ -2394,6 +2394,17 @@ MemTxResult address_space_write_cached_slow(MemoryRegionCache *cache, > hwaddr addr, const void *buf, > hwaddr len); > > +typedef struct MemoryDebugOps { > + MemTxResult (*read)(AddressSpace *as, hwaddr phys_addr, > + MemTxAttrs attrs, void *buf, > + hwaddr len); > + MemTxResult (*write)(AddressSpace *as, hwaddr phys_addr, > + MemTxAttrs attrs, const void *buf, > + hwaddr len); > +} MemoryDebugOps; > + > +void address_space_set_debug_ops(const MemoryDebugOps *ops); > + > static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write) > { > if (is_write) { > diff --git a/softmmu/physmem.c b/softmmu/physmem.c > index a9adedb9f8..057d6d4ce1 100644 > --- a/softmmu/physmem.c > +++ b/softmmu/physmem.c > @@ -166,6 +166,18 @@ struct DirtyBitmapSnapshot { > unsigned long dirty[]; > }; > > +static const MemoryDebugOps default_debug_ops = { > + .read = address_space_read, > + .write = address_space_write_rom > +}; > + > +static const MemoryDebugOps *debug_ops = &default_debug_ops; > + > +void address_space_set_debug_ops(const MemoryDebugOps *ops) > +{ > + debug_ops = ops; > +} > + > static void phys_map_node_reserve(PhysPageMap *map, unsigned nodes) > { > static unsigned alloc_hint = 16; > @@ -3407,6 +3419,10 @@ int cpu_memory_rw_debug(CPUState *cpu, target_ulong addr, > page = addr & TARGET_PAGE_MASK; > phys_addr = cpu_get_phys_page_attrs_debug(cpu, page, &attrs); > asidx = cpu_asidx_from_attrs(cpu, attrs); > + > + /* set debug attrs to indicate memory access is from the debugger */ > + attrs.debug = 1; > + > /* if no physical page mapped, return an error */ > if (phys_addr == -1) > return -1; > @@ -3415,11 +3431,11 @@ int cpu_memory_rw_debug(CPUState *cpu, target_ulong addr, > l = len; > phys_addr += (addr & ~TARGET_PAGE_MASK); > if (is_write) { > - res = address_space_write_rom(cpu->cpu_ases[asidx].as, phys_addr, > - attrs, buf, l); > + res = debug_ops->write(cpu->cpu_ases[asidx].as, phys_addr, > + attrs, buf, l); > } else { > - res = address_space_read(cpu->cpu_ases[asidx].as, phys_addr, > - attrs, buf, l); > + res = debug_ops->read(cpu->cpu_ases[asidx].as, phys_addr, > + attrs, buf, l); > } > if (res != MEMTX_OK) { > return -1; > -- > 2.17.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK