From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-7048-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 80EBA986000 for ; Fri, 10 Apr 2020 10:50:40 +0000 (UTC) References: <20200410033729.24738.22879.stgit@localhost.localdomain> <20200410034150.24738.98143.stgit@localhost.localdomain> From: Paolo Bonzini Message-ID: Date: Fri, 10 Apr 2020 12:50:34 +0200 MIME-Version: 1.0 In-Reply-To: <20200410034150.24738.98143.stgit@localhost.localdomain> Content-Language: en-US Subject: [virtio-dev] Re: [PATCH v19 QEMU 4/4] memory: Do not allow direct write access to rom_device regions Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit To: Alexander Duyck , david@redhat.com, mst@redhat.com Cc: virtio-dev@lists.oasis-open.org, qemu-devel@nongnu.org List-ID: On 10/04/20 05:41, Alexander Duyck wrote: > From: Alexander Duyck > > According to the documentation in memory.h a ROM memory region will be > backed by RAM for reads, but is supposed to go through a callback for > writes. Currently we were not checking for the existence of the rom_device > flag when determining if we could perform a direct write or not. > > To correct that add a check to memory_region_is_direct so that if the > memory region has the rom_device flag set we will return false for all > checks where is_write is set. > > Signed-off-by: Alexander Duyck > --- > include/exec/memory.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/include/exec/memory.h b/include/exec/memory.h > index 1614d9a02c0c..e000bd2f97b2 100644 > --- a/include/exec/memory.h > +++ b/include/exec/memory.h > @@ -2351,8 +2351,8 @@ void address_space_write_cached_slow(MemoryRegionCache *cache, > static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write) > { > if (is_write) { > - return memory_region_is_ram(mr) && > - !mr->readonly && !memory_region_is_ram_device(mr); > + return memory_region_is_ram(mr) && !mr->readonly && > + !mr->rom_device && !memory_region_is_ram_device(mr); > } else { > return (memory_region_is_ram(mr) && !memory_region_is_ram_device(mr)) || > memory_region_is_romd(mr); > Good catch. I queued this up for 5.0. Thanks, Paolo --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org