[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] QEMU commit 04bf2526ce breaks use of xen-mapcache
----- Original Message ----- > From: "Stefano Stabellini" <sstabellini@xxxxxxxxxx> > To: "Paolo Bonzini" <pbonzini@xxxxxxxxxx> > Cc: "Anthony PERARD" <anthony.perard@xxxxxxxxxx>, "Stefano Stabellini" > <sstabellini@xxxxxxxxxx>, > xen-devel@xxxxxxxxxxxxx, qemu-devel@xxxxxxxxxx > Sent: Tuesday, July 25, 2017 8:08:21 PM > Subject: Re: QEMU commit 04bf2526ce breaks use of xen-mapcache > > On Tue, 25 Jul 2017, Paolo Bonzini wrote: > > > Hi, > > > > > > Commits 04bf2526ce (exec: use qemu_ram_ptr_length to access guest ram) > > > start using qemu_ram_ptr_length() instead of qemu_map_ram_ptr(). > > > That result in calling xen_map_cache() with lock=true, but this mapping > > > is never invalidated. > > > So QEMU use more and more RAM until it stop working for a reason or an > > > other. (crash if host have little RAM or stop emulating but no crash) > > > > > > I don't know if calling xen_invalidate_map_cache_entry() in > > > address_space_read_continue() and address_space_write_continue() is the > > > right answer. Is there something better to do ? > > > > I think it's correct for dma to be true... maybe add a lock argument to > > qemu_ram_ptr_length, so that make address_space_{read,write}_continue can > > pass 0 and everyone else passes 1? > > I think that is a great suggestion. That way, the difference between > locked mappings and unlocked mappings would be explicit, rather than > relying on callers to use qemu_map_ram_ptr for unlocked mappings and > qemu_ram_ptr_length for locked mappings. And there aren't that many > callers of qemu_ram_ptr_length, so adding a parameter wouldn't be an > issue. Thanks---however, after re-reading xen-mapcache.c, dma needs to be false for unlocked mappings. Paolo _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx https://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |