This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


[Xen-devel] question about foreign mapped page

To: Xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-devel] question about foreign mapped page
From: schumi.han@xxxxxxxxx
Date: Fri, 12 May 2006 18:44:50 +0800
Delivery-date: Fri, 12 May 2006 05:33:58 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird (Windows/20060308)
Hi, All!
I met a bug when destroyed the VMX. page_remove_rmap() BUG on
page->_mapcount when QEMU exited. I try to solve this problem but I'm
not familiar with MM code. So I wanna ask you guys several questions and hope you can give some clues:
1)If we map a foreign page(DomainU or VMX) to Domain0 through
xc_map_foreign_range, the pfn(in Domain0's memory space)which points to
the mapped mfn should not correlate with any   page structure.  Is  it
right?  I suppose it to be true. The question is when the kernel calls
unmap_page_range, it should try to call vm_normal_page on the related
pte to get the page structure. Which flag will lead vm_normal_page to
return the NULL pointer?
2)IMHO, I expect only the local mapped page, which belongs to the same
domain could be passed to page_remove_rmap and kick out the bug I met!
direct_rmap_pfn_range looks like a suscipious criminal.Is it possible?
But QEMU never used direct_rmap_pfn_range to map local page. So, I'm
really confused!
Thanks for your help!

Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-devel] question about foreign mapped page, schumi . han <=