-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 9/1/15 8:52 AM, Eric Sandeen wrote: > On 8/31/15 5:39 PM, Linus Torvalds wrote: >> On Mon, Aug 31, 2015 at 3:31 PM, Raymond Jennings >> <shentino@xxxxxxxxx> wrote: >>> >>> That said, I wouldn't mind myself if the ext4 driver were given >>> a very grueling regression test to make sure it can actually >>> handle old ext3 systems as well as the ext3 driver can. >> >> That's not my only worry. Things like "can you go back to >> ext3-only" is an issue too - I don't think that's been a big >> priority for ext4 any more, and if there are any existing >> hold-outs that still use ext3, they may want to be able to go >> back to old kernels. > > Others have said it as well, but I'll restate: Yes, you can go > "back." > > But there's no real "going back" needed, because mounting an ext3 > filesystem with ext4.ko hasn't "gone anywhere." If you use > ext4.ko, you are running with a newer driver, but not a newer disk > format. > >> So it's not just a "you can use ext4 instead" issue. Can you do >> that *without* then forcing an upgrade forever on that partition? >> I'm not sure the ext4 people are really even willing to guarantee >> that kind of backwards compatibility. > > Yeah, we are, I think I remember making an explicit stink about > that quite a while ago. But I'm satisfied; we do use > CONFIG_EXT4_USE_FOR_EXT23 in RHEL7, and we wouldn't do that if it > might change disk format behind our users' backs. As a "me too" datapoint, we do the same thing with SLE12. - -Jeff - -- Jeff Mahoney SUSE Labs -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.19 (Darwin) iQIcBAEBAgAGBQJV5cGbAAoJEB57S2MheeWy9z8QALz0EPV2V9MPzSTkQ/DyvcEK V8GxQyHpOSwVLqU/J8f9+1vM7dbRR9bjXuN8YAZ/bmTf5GQA4opuCZK4KanK3xeo JSQeFfO9O4gb3aiKdVxxXS3RhejR4WhQ+nQQ3HOIIXCjauU4vd88UH1tjcBR8PdE DXKtq1KpqIWc5zLr22AgTRwkDiYauaziK2i6922DVl0rSOjfFw4BoV91pgE0pLgi ojXKosmpST1VOlHKw7l2yOeMdVYUn1wJFgOprCXSLNwckszcqLgNbRYaOaiZmh7Z c4zWdOkKQDI1/+THtNniF7xiDx2vFgtCSKbaU+hdsshxBHntLIIRj7vqOqfVLb85 m8lyshQDen8y7bahimCfr/hIGyXBuotl+jS4sryABInBf3AkuR3kI9gYJrb6YDWU jt/0XnT4OIboB1G/Op+SLeNBBR+1RQn9iu559dw2JFQJFeT9JJOvbyaYU5Ijl8I4 eBxebee9laat3atbKVe4HTzGgNzbwCoA8KZuhtaDncR+jd6tsiSLsdlVKZw/P3g9 J35QNlOt6FyecDa9G3OYcpLsxffdv/fke2yT+R6LiN54oVY77OYRjFNY2X27yHWX 76qAOj+tkntfvFV5BjElT+uqXxqebb/kwLt2gUJJ68U/lVVYFHDJKjE2XXdf5omy /N/PcMenBbsGq6H0UvzS =G4VO -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
