> -----Original Message----- > From: Petr Tesarik [mailto:ptesarik at suse.cz] > Sent: Tuesday, August 28, 2012 5:11 PM > To: kexec at lists.infradead.org > Cc: Trapp, Norbert > Subject: [PATCH] makedumpfile: Support for x86_64 1G pages > > The PS bit is not recognized in the Page-Directory-Pointer Table (pgdir > in Linux terms), so virtual addresses that map to a 1G page will be > translated incorrectly. > > This bug affects both Xen and bare metal. I don't think it can be easily > triggered in practice, because 1G mappings are created only for: > > 1. direct 1:1 mapping of physical memory, for which we don't walk the page > tables, but instead subtract the corresponding virtual offset, and > 2. 1G hugepages, which are only used for userspace data. ... Hello again, With Xen not only the Linux kernel has to be considered, but the Xen hypervisor, too. The usage of 1 GB pages by the hypervisor is relevant for machines with recent types of processors and more than a small amount of memory. With kind reagards Norbert Norbert Trapp PBG PDG ES&S SWE OS 6 FUJITSU Fujitsu Technology Solutions GmbH Domagkstra?e 28, D-80807 M?nchen, Germany E-mail: Norbert.Trapp at ts.fujitsu.com Web: ts.fujitsu.com Company details: ts.fujitsu.com/imprint
