From owner-freebsd-stable@FreeBSD.ORG Sun Mar 23 20:38:50 2014 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id B798999A for ; Sun, 23 Mar 2014 20:38:50 +0000 (UTC) Received: from fs.denninger.net (wsip-70-169-168-7.pn.at.cox.net [70.169.168.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 64F22289 for ; Sun, 23 Mar 2014 20:38:49 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by fs.denninger.net (8.14.8/8.14.8) with ESMTP id s2NKcj6O008496 for ; Sun, 23 Mar 2014 15:38:45 -0500 (CDT) (envelope-from karl@denninger.net) Received: from [127.0.0.1] (TLS/SSL) [192.168.1.40] by Spamblock-sys (LOCAL/AUTH); Sun Mar 23 15:38:45 2014 Message-ID: <532F4650.4010101@denninger.net> Date: Sun, 23 Mar 2014 15:38:40 -0500 From: Karl Denninger User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: freebsd-stable@freebsd.org Subject: Re: ZFS cautions (pool flag additions committed) References: <532F1ED8.8010004@denninger.net> <532F313B.5040809@weboutsourcing.cz> In-Reply-To: <532F313B.5040809@weboutsourcing.cz> Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha1; boundary="------------ms020504010801080703020500" X-Antivirus: avast! (VPS 140323-1, 03/23/2014), Outbound message X-Antivirus-Status: Clean X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 23 Mar 2014 20:38:50 -0000 This is a cryptographically signed message in MIME format. --------------ms020504010801080703020500 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable On 3/23/2014 2:08 PM, Ondra Knezour wrote: > Dne 23.3.2014 18:50, Karl Denninger napsal(a): >> When ZFS code imports are brought forward that add feature flags there= >> is a potential time bomb for existing users in that creation of a new >> pool becomes non-revertible (except read-only!) with regard to mountin= g >> on older revisions of the code. >> >> .... >> The primary "gotcha" here occurs if you don't upgrade your emergency >> boot media and for some reason you need to boot from a CD or USB key -= - >> you can be left SEVERELY screwed, and since -RELEASE is typically not >> rebuilt when this happens if you don't have a second machine laying >> around on which you can build a RELEASE image.... >> > > Excellent candidate for the /usr/src/UPDATING file? I think so. The only reason I caught it immediately is that I'm in the arc.c code=20 right now with the fix for the "stalls", and caught the file being=20 flagged as revved and thus not automatically updated when I did a "svn=20 update ." on /usr/src. ZFS has been (reasonably) stable on feature-set for a while, but now=20 we're seeing more pool-level flags show up and in virtually every case=20 once those are turned on you can't shut them back off, which slams a=20 door on you in terms of being able to revert if something goes wrong. --=20 -- Karl karl@denninger.net --------------ms020504010801080703020500 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIIFTzCC BUswggQzoAMCAQICAQgwDQYJKoZIhvcNAQEFBQAwgZ0xCzAJBgNVBAYTAlVTMRAwDgYDVQQI EwdGbG9yaWRhMRIwEAYDVQQHEwlOaWNldmlsbGUxGTAXBgNVBAoTEEN1ZGEgU3lzdGVtcyBM TEMxHDAaBgNVBAMTE0N1ZGEgU3lzdGVtcyBMTEMgQ0ExLzAtBgkqhkiG9w0BCQEWIGN1c3Rv bWVyLXNlcnZpY2VAY3VkYXN5c3RlbXMubmV0MB4XDTEzMDgyNDE5MDM0NFoXDTE4MDgyMzE5 MDM0NFowWzELMAkGA1UEBhMCVVMxEDAOBgNVBAgTB0Zsb3JpZGExFzAVBgNVBAMTDkthcmwg RGVubmluZ2VyMSEwHwYJKoZIhvcNAQkBFhJrYXJsQGRlbm5pbmdlci5uZXQwggIiMA0GCSqG SIb3DQEBAQUAA4ICDwAwggIKAoICAQC5n2KBrBmG22nVntVdvgKCB9UcnapNThrW1L+dq6th d9l4mj+qYMUpJ+8I0rTbY1dn21IXQBoBQmy8t1doKwmTdQ59F0FwZEPt/fGbRgBKVt3Quf6W 6n7kRk9MG6gdD7V9vPpFV41e+5MWYtqGWY3ScDP8SyYLjL/Xgr+5KFKkDfuubK8DeNqdLniV jHo/vqmIgO+6NgzPGPgmbutzFQXlxUqjiNAAKzF2+Tkddi+WKABrcc/EqnBb0X8GdqcIamO5 SyVmuM+7Zdns7D9pcV16zMMQ8LfNFQCDvbCuuQKMDg2F22x5ekYXpwjqTyfjcHBkWC8vFNoY 5aFMdyiN/Kkz0/kduP2ekYOgkRqcShfLEcG9SQ4LQZgqjMpTjSOGzBr3tOvVn5LkSJSHW2Z8 Q0dxSkvFG2/lsOWFbwQeeZSaBi5vRZCYCOf5tRd1+E93FyQfpt4vsrXshIAk7IK7f0qXvxP4 GDli5PKIEubD2Bn+gp3vB/DkfKySh5NBHVB+OPCoXRUWBkQxme65wBO02OZZt0k8Iq0i4Rci WV6z+lQHqDKtaVGgMsHn6PoeYhjf5Al5SP+U3imTjF2aCca1iDB5JOccX04MNljvifXgcbJN nkMgrzmm1ZgJ1PLur/ADWPlnz45quOhHg1TfUCLfI/DzgG7Z6u+oy4siQuFr9QT0MQIDAQAB o4HWMIHTMAkGA1UdEwQCMAAwEQYJYIZIAYb4QgEBBAQDAgWgMAsGA1UdDwQEAwIF4DAsBglg hkgBhvhCAQ0EHxYdT3BlblNTTCBHZW5lcmF0ZWQgQ2VydGlmaWNhdGUwHQYDVR0OBBYEFHw4 +LnuALyLA5Cgy7T5ZAX1WzKPMB8GA1UdIwQYMBaAFF3U3hpBZq40HB5VM7B44/gmXiI0MDgG CWCGSAGG+EIBAwQrFilodHRwczovL2N1ZGFzeXN0ZW1zLm5ldDoxMTQ0My9yZXZva2VkLmNy bDANBgkqhkiG9w0BAQUFAAOCAQEAZ0L4tQbBd0hd4wuw/YVqEBDDXJ54q2AoqQAmsOlnoxLO 31ehM/LvrTIP4yK2u1VmXtUumQ4Ao15JFM+xmwqtEGsh70RRrfVBAGd7KOZ3GB39FP2TgN/c L5fJKVxOqvEnW6cL9QtvUlcM3hXg8kDv60OB+LIcSE/P3/s+0tEpWPjxm3LHVE7JmPbZIcJ1 YMoZvHh0NSjY5D0HZlwtbDO7pDz9sZf1QEOgjH828fhtborkaHaUI46pmrMjiBnY6ujXMcWD pxtikki0zY22nrxfTs5xDWGxyrc/cmucjxClJF6+OYVUSaZhiiHfa9Pr+41okLgsRB0AmNwE f6ItY3TI8DGCBQowggUGAgEBMIGjMIGdMQswCQYDVQQGEwJVUzEQMA4GA1UECBMHRmxvcmlk YTESMBAGA1UEBxMJTmljZXZpbGxlMRkwFwYDVQQKExBDdWRhIFN5c3RlbXMgTExDMRwwGgYD VQQDExNDdWRhIFN5c3RlbXMgTExDIENBMS8wLQYJKoZIhvcNAQkBFiBjdXN0b21lci1zZXJ2 aWNlQGN1ZGFzeXN0ZW1zLm5ldAIBCDAJBgUrDgMCGgUAoIICOzAYBgkqhkiG9w0BCQMxCwYJ KoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0xNDAzMjMyMDM4NDBaMCMGCSqGSIb3DQEJBDEW BBRQb7CMMh3OmZBzVIUG4q43QeeRyjBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIG0BgkrBgEEAYI3EAQxgaYwgaMwgZ0xCzAJBgNV BAYTAlVTMRAwDgYDVQQIEwdGbG9yaWRhMRIwEAYDVQQHEwlOaWNldmlsbGUxGTAXBgNVBAoT EEN1ZGEgU3lzdGVtcyBMTEMxHDAaBgNVBAMTE0N1ZGEgU3lzdGVtcyBMTEMgQ0ExLzAtBgkq hkiG9w0BCQEWIGN1c3RvbWVyLXNlcnZpY2VAY3VkYXN5c3RlbXMubmV0AgEIMIG2BgsqhkiG 9w0BCRACCzGBpqCBozCBnTELMAkGA1UEBhMCVVMxEDAOBgNVBAgTB0Zsb3JpZGExEjAQBgNV BAcTCU5pY2V2aWxsZTEZMBcGA1UEChMQQ3VkYSBTeXN0ZW1zIExMQzEcMBoGA1UEAxMTQ3Vk YSBTeXN0ZW1zIExMQyBDQTEvMC0GCSqGSIb3DQEJARYgY3VzdG9tZXItc2VydmljZUBjdWRh c3lzdGVtcy5uZXQCAQgwDQYJKoZIhvcNAQEBBQAEggIAaoklS+oP657q3Ip3jW0ud9VWaqRK Li1qxtrZ9mUBaLyfmM7wmzHoGOONdTy/ta/4W5Q0ON6Hzouns3DUC/QHpawXcJ1CZxkvd5jj YxHc18vwNOokA17RKRCzt5fux4iPbqbHfEVDDHBqy6sW/aj3Q/J9I79RaTIDpCS/axd2kkTO aF0fqkS2LrpxNYHVp1whn71KIvH0E287J9qWlBlnb2eNaCXE8GYB3MNFm5fHjuP3vWCzjVsL 7pOKJXDEBEnuxgWdK1+X0xUHDtr7aMGmEw6XwYCwV/XFBQGWBpuOVJJrErkhKXHgPC0ZjTVg v5AU7Ocv0fyjPxXR85HohkYn1YgHVInQtvqF+cmgUTTs7lwgfQpaBVgObpBXoLUOIEja7Weq Ldh3+/mpNJPSuMO6XeQCD/5nuPXI9nZx+p3xGdvqQhFtFB4nGjY7Npho9wOtR0moGLvKBmW+ aLwHoe2aQWGNtIsphBFikUygTYjj1aEwSvs/ErpncEqYHcS4tHugTeWOSPzpLAasDmiS2Wto G5jyX3sIZdqaL3tKh9XWyb1/bqvuJ7Q7TAO2rS/agOP+3QgrBrmHVCsvnL9KwGJ01pqzFmfE NJtkO1QeawKaV7owcJekj74E09ADvzNv8ECdx8EGf2ywCgVGjySsRtOSlBQSU2RK/A5VG1D7 yy6NnO4AAAAAAAA= --------------ms020504010801080703020500--