> -----Original Message----- > From: Jan Beulich <jbeul...@suse.com> > Sent: 26 February 2020 13:58 > To: Durrant, Paul <pdurr...@amazon.co.uk> > Cc: xen-devel@lists.xenproject.org; Stefano Stabellini > <sstabell...@kernel.org>; Julien Grall <jul...@xen.org>; Volodymyr Babchuk > <volodymyr_babc...@epam.com>; Andrew Cooper <andrew.coop...@citrix.com>; > George Dunlap <george.dun...@citrix.com>; Ian Jackson > <ian.jack...@eu.citrix.com>; Konrad Rzeszutek Wilk > <konrad.w...@oracle.com>; Wei Liu <w...@xen.org> > Subject: Re: [PATCH 2/2] domain: use PGC_extra domheap page for > shared_info > > On 25.02.2020 10:53, Paul Durrant wrote: > > There's no particular reason shared_info need use a xenheap page. It's > > only purpose is to be mapped by the guest so use a PGC_extra domheap > page > > instead. > > Since the cover letter also doesn't give any background - is there a > problem with the current arrangements? Are there any further plans > depending on this being changed? Or is this simply "let's do it > because now we can"? >
The general direction is to get rid of shared xenheap pages. Knowing that a xenheap page is not shared with a guest makes dealing with live update much easier, and also allows a chunk of code to be removed from domain_relinquish_resoureses() (the shared xenheap walk which de-assigns them from the dying guest). The only xenheap pages shared with a normal domU (as opposed to a system domain, which would be re-created on live update anyway) are AFAICT shared-info and grant table/status frames. This series deals with shared-info but I do have proto-patches for the grant table code too. Paul _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
