From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f169.google.com ([209.85.223.169]:35490 "EHLO mail-io0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755877AbbJ1LYs (ORCPT ); Wed, 28 Oct 2015 07:24:48 -0400 Received: by iofz202 with SMTP id z202so6550515iof.2 for ; Wed, 28 Oct 2015 04:24:47 -0700 (PDT) Subject: Re: random i/o error without error in dmesg To: Duncan <1i5t5.duncan@cox.net>, linux-btrfs@vger.kernel.org References: <562E0D31.2080003@dblaci.hu> <5339076.FcC2BAjqs5@thetick> <1844690.p2LsPbdn9l@thetick> From: Austin S Hemmelgarn Message-ID: <5630B040.8020203@gmail.com> Date: Wed, 28 Oct 2015 07:23:44 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms040804000008040300040903" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms040804000008040300040903 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-10-28 01:21, Duncan wrote: > Marc Joliet posted on Tue, 27 Oct 2015 21:54:40 +0100 as excerpted: > >>> IOW, does it take a full reboot to clear the problem, or is a simple >>> ro/rw mount cycle enough, or an unmount/remount? >> >> Seems that a full reboot is needed, but I would expect that it would >> have the same effect if I were to pivot back into the initramfs, unmou= nt >> / from there, >> then boot back into the system. Because quite frankly, I can't think = of >> any reason why a power cycle to the SSD should make a difference here.= >> I vaguely remember that systemd can do that, so I'll see if I can find= >> out how. > > Agree with both the systemd returning to the initr* point (which I > actually had in mind while writing the above but don't remember the > details either, so chose to omit in the interest of limiting the size o= f > the reply and research necessary to generate it), and the ssd power-cyc= le > point. > >>> Finally, assuming root itself isn't btrfs, if you have btrfs configur= ed >>> as a module, you could try unmounting all btrfs and then unloading th= e >>> module, then reloading and remounting. That should entirely clear al= l >>> in-memory btrfs state, so if that doesn't solve the problem, while >>> rebooting does, then the problem's very possibly outside of btrfs sco= pe. >>> Of course if root is btrfs, you can't really check that. >> >> Nope, btrfs is built-in (though it doesn't have to be, what with me >> using an initramfs). > > Same here, also gentoo as I guess you know from previous exchanges. Bu= t > unfortunately, if your initr* is anything like mine, and your kernel > monolithic as mine, making btrfs a module with a btrfs root isn't the > easy thing it might seem to those who run ordinary distro supplied bina= ry > kernels with pretty much everything modularized, as doing so involves a= > whole new set of research on how to get that module properly included i= n > the initr* and loaded there, as well as installing and building the who= le > module-handling infrastructure (modprobe and friends) again, as it's no= t > actually installed on the system at all at this point, because with the= > kernel entirely monolithic, module-handling tools are unnecessary and > thus just another unnecessary package to have to keep building updates > for, if they remain installed. FWIW, I'm pretty sure that genkernel-next (and possibly genkernel too at = this point, but that's never had working userland support for BTRFS=20 AFAICT) includes btrfs.ko and it's dependencies in any initr* it=20 generates when it sees those modules on the system, although I'm not=20 100% certain because I always build the driver for my root filesystem=20 into the kernel directly. > [ snip ] > What's left in the lib_user list after a dip to emergency mode, whether= > you've returned to multi-user mode or not, is often only systemd and > perhaps its journald service, itself. Journald can be restarted manual= ly > in the usual way (systemctl restart journald.service or whatever, I > usually use tab completion so don't pay all that much attention to the > specific name), if necessary, while systemd itself can be "reexecuted" > using the systemctl daemon-reexec (tab-completion again) command. Udev might also be listed (for some reason, a lot of distros don't stop=20 it when going to emergency mode, I don't know about what Gentoo does in=20 this case though because I don't use systemd), and at least the last=20 time I checked, dropping to emergency mode on Debian and Fedora testing=20 versions also keeps any dhcp clients or other stuff needed for=20 maintaining the network connection running as well. --------------ms040804000008040300040903 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 Brgwgga0MIIEnKADAgECAgMRLfgwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwOTIxMTEzNTEzWhcNMTYwMzE5MTEzNTEzWjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz 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 b20wDQYJKoZIhvcNAQENBQADggIBADMnxtSLiIunh/TQcjnRdf63yf2D8jMtYUm4yDoCF++J jCXbPQBGrpCEHztlNSGIkF3PH7ohKZvlqF4XePWxpY9dkr/pNyCF1PRkwxUURqvuHXbu8Lwn 8D3U2HeOEU3KmrfEo65DcbanJCMTTW7+mU9lZICPP7ZA9/zB+L0Gm1UNFZ6AU50N/86vjQfY WgkCd6dZD4rQ5y8L+d/lRbJW7ZGEQw1bSFVTRpkxxDTOwXH4/GpQfnfqTAtQuJ1CsKT12e+H NSD/RUWGTr289dA3P4nunBlz7qfvKamxPymHeBEUcuICKkL9/OZrnuYnGROFwcdvfjGE5iLB kjp/ttrY4aaVW5EsLASNgiRmA6mbgEAMlw3RwVx0sVelbiIAJg9Twzk4Ct6U9uBKiJ8S0sS2 8RCSyTmCRhJs0vvva5W9QUFGmp5kyFQEoSfBRJlbZfGX2ehI2Hi3U2/PMUm2ONuQG1E+a0AP u7I0NJc/Xil7rqR0gdbfkbWp0a+8dAvaM6J00aIcNo+HkcQkUgtfrw+C2Oyl3q8IjivGXZqT 5UdGUb2KujLjqjG91Dun3/RJ/qgQlotH7WkVBs7YJVTCxfkdN36rToPcnMYOI30FWa0Q06gn F6gUv9/mo6riv3A5bem/BdbgaJoPnWQD9D8wSyci9G4LKC+HQAMdLmGoeZfpJzKHMYIE0TCC BM0CAQEwgYAweTEQMA4GA1UEChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNl cnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcN AQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DANBglghkgBZQMEAgMFAKCCAiEwGAYJKoZI hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUxMDI4MTEyMzQ0WjBPBgkq hkiG9w0BCQQxQgRAz/JTBMXp/2QsIfWqtdJaiRzquR5k7pub7quxjmy7Fv+xB9H7hLBNDrbC ZbNgZgJg9Fltfh7SbHoTf+KBw2HEITBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxEt+DCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DAN BgkqhkiG9w0BAQEFAASCAgAQAs04ZrAINsag4Hs+ENZvu0RaE/t+JCR+G7zhLD3FF0yb5DpJ EUY1/bjxiFDO8MZKWgblVaCarahB16oAxnV68HHO8jEEr1Ug5tA8wLEE81G399OIlKrLE9wc KCzaAk22vX3pw9YpW1MAuBYOezXISiiWmLwxFS3oiSFllvAuZEoSegs9FLBT8cjJ+xUO8/zo R4Ke2CukcT8sLgBwtgs+Xa5YDLt4coS6zymylLwKKzfYCXpT7PD6v6Tr3EcRk+1aN9DrIgEM 60gsjGbs/c4+Ss4OoQw4FV1Z0JeZGY/VGxVF8e9Kl3HIN5/EwFkxjxxq79m7aOLPn0ik6bmr L0OTkuJdqYISm6KaO7/e3siz3C7twX23Y+0/yWDOSQU3jHRcFZ1wkXd8/+CRvsf6dFv9GsTL fwwF2Fqcgn1IoKpVhe2/V7w9MfxkB/6mbFadks7MQMndPFY57ImQLJ7QlxScdDqBLTYZslGl RO9ShKZ0njUeGH62WH9nI0hVufF9rHao7N6Q26Lj+NMyn3k0KwVqxXxRpLenx3NRi/CXba1Y NKZI5jbmYdJCyKsHW2Xe3BWOuNdXDyVAHsqSZA0SEWv3MpA9Pa0/znoJiMEM2UmVI0dUhgr1 f/sSvAdytEPQ2h7IeTwuFWs52rMSXIpjiIkuWpof4zceR1IMUNOntUsySQAAAAAAAA== --------------ms040804000008040300040903--