Am 01.08.2012 17:52, schrieb Paolo Bonzini: > Il 23/07/2012 18:32, Paolo Bonzini ha scritto: >> Il 03/07/2012 15:20, Paolo Bonzini ha scritto: >>>> These patches let virtio-blk use the new support for toggling the cache >>>> mode between writethrough and writeback. >>>> >>>> The first patch introduces a new feature bit and configuration field to >>>> do this. The second patch disables writeback caching for guests that do >>>> not negotiate VIRTIO_BLK_F_WCACHE (meaning that they cannot send flush >>>> requests), so that limited or older guests are now safe wrt power losses. >>>> VIRTIO_BLK_F_FLUSH has been introduced in Linux 2.6.32 (in 2009) and was >>>> backported to RHEL/CentOS 5.6 (in 2010). >>>> >>>> The Windows drivers (which work by emulating SCSI on top of virtio-blk) >>>> have bugs in this area, which I reported on the Red Hat Bugzilla as >>>> bugs 837321 and 837324. With these patches they will suffer a >>>> performance hit but gain correctness. >>>> >>>> Paolo Bonzini (2): >>>> virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE >>>> virtio-blk: disable write cache if not negotiated >> Ping - Anthony, mst? > > Ping^2, so we can switch writethrough->writeback in 1.2. Speak now or forever hold your peace. If there are no more comments until Friday, I'll just apply it. Kevin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
