From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44139) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VPbHW-0002Z7-PF for qemu-devel@nongnu.org; Fri, 27 Sep 2013 12:52:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VPbHQ-0005hh-QQ for qemu-devel@nongnu.org; Fri, 27 Sep 2013 12:52:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:63544) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VPbHQ-0005hb-Hj for qemu-devel@nongnu.org; Fri, 27 Sep 2013 12:52:36 -0400 Message-ID: <5245B7E2.7030303@redhat.com> Date: Fri, 27 Sep 2013 18:52:50 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1380300560-21086-1-git-send-email-akong@redhat.com> In-Reply-To: <1380300560-21086-1-git-send-email-akong@redhat.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] extend limit of physical sections number List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amos Kong Cc: peter.maydell@linaro.org, qemu-devel@nongnu.org, anthony@codemonkey.ws Il 27/09/2013 18:49, Amos Kong ha scritto: > # qemu -drive file=/disk0,if=none,id=v0,format=qcow2 \ > -device virtio-blk-pci,drive=v0,id=v00,multifunction=on,addr=0x04.0 > .... > > Launching guest with more than 32 virtio-blk disks, > qemu will crash, because there are too many BARs. > > This patch brings the limit of non-tcg up by a factor > of 8 (32767 / 4096), i.e. 32*8 = 256. > > Signed-off-by: Paolo Bonzini > Signed-off-by: Amos Kong > --- > exec.c | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/exec.c b/exec.c > index 5aef833..f639c01 100644 > --- a/exec.c > +++ b/exec.c > @@ -763,11 +763,18 @@ void phys_mem_set_alloc(void *(*alloc)(ram_addr_t)) > > static uint16_t phys_section_add(MemoryRegionSection *section) > { > - /* The physical section number is ORed with a page-aligned > - * pointer to produce the iotlb entries. Thus it should > - * never overflow into the page-aligned value. > - */ > - assert(next_map.sections_nb < TARGET_PAGE_SIZE); > + if (tcg_enabled()) { > + /* The physical section number is ORed with a page-aligned > + * pointer to produce the iotlb entries. Thus it should > + * never overflow into the page-aligned value. > + */ > + assert(next_map.sections_nb < TARGET_PAGE_SIZE); > + } else { > + /* For KVM or Xen we can use the full range of the ptr field > + * in PhysPageEntry. > + */ > + assert(next_map.sections_nb < SHRT_MAX); > + } > > if (next_map.sections_nb == next_map.sections_nb_alloc) { > next_map.sections_nb_alloc = MAX(next_map.sections_nb_alloc * 2, > Thanks for testing this patch Amos! Paolo