From: Austin S Hemmelgarn Subject: Re: [GIT PULL] Ext3 removal, quota & udf fixes Date: Wed, 2 Sep 2015 09:28:37 -0400 Message-ID: <55E6F985.3080105@gmail.com> References: <20150831061920.GA2751@quack.suse.cz> <55E4D5DE.2030709@gmail.com> <55E5FF01.2000304@gmail.com> <55E68D49.5000404@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms010004060509090707060600" Cc: Linus Torvalds , Jan Kara , LKML , "linux-ext4@vger.kernel.org" , linux-fsdevel To: Raymond Jennings , Albino B Neto Return-path: In-Reply-To: <55E68D49.5000404@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org This is a cryptographically signed message in MIME format. --------------ms010004060509090707060600 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-09-02 01:46, Raymond Jennings wrote: > On 09/01/15 20:30, Albino B Neto wrote: >> 2015-08-31 23:53 GMT-03:00 Theodore Ts'o : >>> Yes, you can go back to ext3-only. In fact, we do *not* automaticall= y >>> upgrade the file system to use ext4-specific features. >>>> 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. >>> Actually, we do guarantee this. It's considered poor form to >>> automatically change the superblock to add new file system features i= n >>> a way that would break the ability for the user to roll back to an >>> older kernel. This isn't just for ext3->ext4, but for new ext4 >>> features such as metadata checksumming. The user has to explicitly >>> enable the feature using "tune2fs -O new_feature /dev/sdXX". >> Yeah! >> >> 2015-09-01 16:39 GMT-03:00 Austin S Hemmelgarn := >>> NO, it is not logical. A vast majority of Android smartphones in the= >>> wild >>> use ext2, as do a very significant portion of embedded systems that >>> don't >>> have room for the few hundred kilobytes of extra code that the ext4 >>> driver >>> has in comparison to ext2. >> Ext2 portion embedded and Ext3 many machines. > > So basically the game plan is gutting ext3 because code-dupe with ext4,= > but keep ext2 because ext4 is too big for embedded to outright replace > ext2? > > Hmm...are there any embedded systems out there that use ext3 and can fi= t > its code ext3 but not ext4? Probably, but I don't know of any myself. TBH, the systems that use=20 ext2 because of space savings are usually ones with less than 64M of=20 RAM, which is becoming a smaller and smaller market share. --------------ms010004060509090707060600 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgMFADCABgkqhkiG9w0BBwEAAKCC Brgwgga0MIIEnKADAgECAgMQblUwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwMzI1MTkzNDM4WhcNMTUwOTIxMTkzNDM4WjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz ZXIxIzAhBgkqhkiG9w0BCQEWFGFoZmVycm9pbjdAZ21haWwuY29tMSIwIAYJKoZIhvcNAQkB FhNhaGVtbWVsZ0BvaGlvZ3QuY29tMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA nQ/81tq0QBQi5w316VsVNfjg6kVVIMx760TuwA1MUaNQgQ3NyUl+UyFtjhpkNwwChjgAqfGd LIMTHAdObcwGfzO5uI2o1a8MHVQna8FRsU3QGouysIOGQlX8jFYXMKPEdnlt0GoQcd+BtESr pivbGWUEkPs1CwM6WOrs+09bAJP3qzKIr0VxervFrzrC5Dg9Rf18r9WXHElBuWHg4GYHNJ2V Ab8iKc10h44FnqxZK8RDN8ts/xX93i9bIBmHnFfyNRfiOUtNVeynJbf6kVtdHP+CRBkXCNRZ qyQT7gbTGD24P92PS2UTmDfplSBcWcTn65o3xWfesbf02jF6PL3BCrVnDRI4RgYxG3zFBJuG qvMoEODLhHKSXPAyQhwZINigZNdw5G1NqjXqUw+lIqdQvoPijK9J3eijiakh9u2bjWOMaleI SMRR6XsdM2O5qun1dqOrCgRkM0XSNtBQ2JjY7CycIx+qifJWsRaYWZz0aQU4ZrtAI7gVhO9h pyNaAGjvm7PdjEBiXq57e4QcgpwzvNlv8pG1c/hnt0msfDWNJtl3b6elhQ2Pz4w/QnWifZ8E BrFEmjeeJa2dqjE3giPVWrsH+lOvQQONsYJOuVb8b0zao4vrWeGmW2q2e3pdv0Axzm/60cJQ haZUv8+JdX9ZzqxOm5w5eUQSclt84u+D+hsCAwEAAaOCAVkwggFVMAwGA1UdEwEB/wQCMAAw VgYJYIZIAYb4QgENBEkWR1RvIGdldCB5b3VyIG93biBjZXJ0aWZpY2F0ZSBmb3IgRlJFRSBo ZWFkIG92ZXIgdG8gaHR0cDovL3d3dy5DQWNlcnQub3JnMA4GA1UdDwEB/wQEAwIDqDBABgNV HSUEOTA3BggrBgEFBQcDBAYIKwYBBQUHAwIGCisGAQQBgjcKAwQGCisGAQQBgjcKAwMGCWCG SAGG+EIEATAyBggrBgEFBQcBAQQmMCQwIgYIKwYBBQUHMAGGFmh0dHA6Ly9vY3NwLmNhY2Vy dC5vcmcwMQYDVR0fBCowKDAmoCSgIoYgaHR0cDovL2NybC5jYWNlcnQub3JnL3Jldm9rZS5j cmwwNAYDVR0RBC0wK4EUYWhmZXJyb2luN0BnbWFpbC5jb22BE2FoZW1tZWxnQG9oaW9ndC5j b20wDQYJKoZIhvcNAQENBQADggIBABr5e8W+NiTER+Q/7wiA2LxWN3UdhT3eZJjqqSlP370P KL5iWqeTfxQ67Ai/mHbJcT2PgAJ+/D2Ji+aRR03UWnU/vtOwzyDLUMstqnfl0Zs+sz/CJe7x nBA5jlpjC2DKuMVfbPze7eySaen7XSGFHKE1QoVIIpQ2kVjC4nbbJQnUbAVX1Iz29WxeVGt9 XYigz3tDPf3tglN+q23E7YjQl4abTIoM7i98yV1H9gfY8lFfKZ6jREB9+n6ie2EwS3Kat2mG tl2wBx4MfRnoSQSKsLKQ5oTwhWf0JqlFwpLfl374p0Njcykej9/jnWG8Ks1V/AXTHqI4eyIP Mf5yMZkPv7n7LS9WWKdG4Nd38iv4T2EiAaWsmgu+r81qL5CJu9AyA0SBS4ttKf6k3e63w2Mv N9R45vpQ3QhAhfWyFxFhZN95APe3YECDG3+XIRJpRYPEtHuIsOyzI70ajF93gg/BidvqKsmV MM2ccktDMfqwZXea6zey7F8Geu9R7BqjXmG2HlNuXu7e/xnHOgXf5D3wPmnRLlBhXL1Ch97a w2KjaupjpAHfFjv5kGnZXN87UvvlwzIZiKXwa3vTDwK+rrKn/sHPkfDZPSiyt/ZBIK6lX83P 34H/CzGg+Kx57rHYOIHGumIvpDa5vfWp8O0sGgawb1C2Aae4sTUVIWmIjVuGI062MYIE0TCC BM0CAQEwgYAweTEQMA4GA1UEChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNl cnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcN AQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTANBglghkgBZQMEAgMFAKCCAiEwGAYJKoZI hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUwOTAyMTMyODM3WjBPBgkq hkiG9w0BCQQxQgRAGoys1azm3Yahhi/kStQRrrI9N0xW7etEwKNHyXhSpuZnnjdHuJaKKQ5N DvIIM4TsPUMlg7qyOqh+QTGpcUcUhTBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxBuVTCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTAN BgkqhkiG9w0BAQEFAASCAgBjlUR/j0FnLYhhfsDMVKkUFZNk/p4PmTOOW7JR7LLzuAfOvZo/ 1LwqlqGwnBOTqvhmlI7ZDuHEDpIrS18zInYNUI5232I4VHuSI+VU1MlwUvmST9BoS+Cnlql3 SvkaqymHs5DUHDagXVg4uVWvPZ3DRbJHJZb+p/riCXZLbJwW0shlkcA8sk9VsawvD3k8R9rK 5f8g+5aykwiv2Z6xzuyP8RvtXygt08UuYtrChgZU9u78pNRmE92ZJ1S4CpH7IiJDa6OyUZ/x L6QQmNd6d5MKAPDnvrrngEaogBRREFpqxLYJzAzyFXBqIK34pOC1h2ANT8tCvq7EVrw7OKd5 CPVmFMX3WvYfdbGZJxqdAz85/g4Ewg54lAZPiIP7/NEjapBW7jHRn50s1keUn6uGAa8bOXP5 SNDp0CpF/giOfPGlQpEStlZWBw0DvDk/c2g4f08crdC8B5dKwCQ/OSQaXYKYJ7KudW8MXX9M nYN2/LRFNsuOqFh0wgyWe8ycDIo4PtJSbLxVOWIVCzCcI50iFiaZXPkunpVdUVR91N9FXEgj m0/vXG4hZTlVh9qPPJHZRrMp+5J/gdqu2V24NmuaH3SkqvpweMF8wrJ7AV2NrifKtFTpqxiA VTS6SS6SoLFZU7CDOXe635MxgVh5BlNJ5RkkA7ghIv3vw8vtmux3i3F80gAAAAAAAA== --------------ms010004060509090707060600--