Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx2.netapp.com ([216.240.18.37]:62350 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759335Ab2EPWK6 (ORCPT ); Wed, 16 May 2012 18:10:58 -0400 From: "Adamson, Dros" To: "J. Bruce Fields" CC: linux-nfs list Subject: Re: [PATCH] nfsd: return 0 on reads of fault injection files Date: Wed, 16 May 2012 22:10:55 +0000 Message-ID: <99C4F6D8-3BBF-4502-B41C-A71B2ADB6207@netapp.com> References: <1336678270-791-1-git-send-email-dros@netapp.com> <20120516211621.GE20487@fieldses.org> <20120516215847.GF20487@fieldses.org> In-Reply-To: <20120516215847.GF20487@fieldses.org> Content-Type: multipart/signed; boundary="Apple-Mail=_F523182B-B871-467B-A73A-93525A12C987"; protocol="application/pkcs7-signature"; micalg=sha1 MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: --Apple-Mail=_F523182B-B871-467B-A73A-93525A12C987 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 On May 16, 2012, at 5:58 PM, J. Bruce Fields wrote: > On Wed, May 16, 2012 at 09:50:32PM +0000, Adamson, Dros wrote: >> No, I haven't messed with it that much - I had other tasks take a >> higher priority, but I'm back on it as of this afternoon. >>=20 >> I'll try nfsd-next to get CB_PATH_DOWN without fault_injection and >> report back to you. Also, I think we need to modify nfsd >> (nfsd4_new_conn()) to set cl_cb_state to NFSD4_CB_UNKNOWN on a >> successful BIND_CONN_TO_SESSION (IFF it's CB_DOWN with the right >> direction), otherwise the CB_PATH_DOWN flag will be set on every >> sequence OP >=20 > That's intentional: >=20 > http://www.ietf.org/mail-archive/web/nfsv4/current/msg10840.html Right... >=20 >> and the client will keep sending BIND_CONN_TO_SESSION. >> The idea is that once we call nfsd4_new_conn, we won't know if the >> back channel is really up until a callback is attempted. >=20 > If the client hasn't given us a connection to use as the backchannel, > then we *know* the backchannel is down, we don't need to try sending a > callback (how could we?). The point is that the client *has* given us a connection to use as the = backchannel with the BIND_CONN_TO_SESSION call. On the server, nfs4_new_conn() was called and was successful, but = cl_cb_state is still set to CB_DOWN and will never change. >=20 >> Setting it to CB_UNKNOWN stops the loop of (sequence, bind_conn, >> sequence, bind_conn, =85), but doesn't actually mark it as "UP" until = a >> callback is successful. >=20 > If the client is attempting to clear the CB_PATH_DOWN flag by sending = us > a BIND_CONN_TO_SESSION that doesn't actually give us a backchannel, = then > it's confused. The client *is* giving us a backchannel by sending the server a = BIND_CONNN_TO_SESSION! The server accepts the call, adds the "new = connection" via nfs4_new_conn(), but the problem is the internal state = of nfsd never changes from CB_DOWN. -dros > If the client really doesn't care whether the backchannel is down or = not > then it can ignore the flag--it's a flag, not an error. >=20 > --b. --Apple-Mail=_F523182B-B871-467B-A73A-93525A12C987 Content-Disposition: attachment; filename="smime.p7s" Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIIDTzCCA0sw ggIzoAMCAQICAQEwCwYJKoZIhvcNAQEFMEYxFzAVBgNVBAMMDldlc3RvbiBBZGFtc29uMQswCQYD VQQGEwJVUzEeMBwGCSqGSIb3DQEJARYPZHJvc0BuZXRhcHAuY29tMB4XDTExMDYwODIyMDc0NloX DTEyMDYwNzIyMDc0NlowRjEXMBUGA1UEAwwOV2VzdG9uIEFkYW1zb24xCzAJBgNVBAYTAlVTMR4w HAYJKoZIhvcNAQkBFg9kcm9zQG5ldGFwcC5jb20wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEK AoIBAQC8/tJxtovJEXYRfSsrFOWKHxIZGY7/2mBee1DpWuoGDbVNapefCC7WXe+Nqxz609w2J/Mk /k3trZ3Ge2NXK0tGnP9NzjkzpGA7rSpM3wUFsvbLMUEGfQpvV24/nYvcLHTvOOEUaDPpHduN94bD dwvyowzDIRIpF2MeRnOzBNeHkrGHlZdzPmGjm8tkhrDRRkDYHhlxaiG4z30KCfAazxomuINiy1kj vbndXooYMDoh9H63hgW4NkOedtLdflLa322DXQ3nFU7YbyOIjHVl1tgWJLDWf7WT3lsAB8KvuJZ5 zhsUB+fqxCKPJVRPDO1gjChvvtGiG1tGUUZz0H9Wx00zAgMBAAGjRjBEMA4GA1UdDwEB/wQEAwIH gDAWBgNVHSUBAf8EDDAKBggrBgEFBQcDBDAaBgNVHREEEzARgQ9kcm9zQG5ldGFwcC5jb20wDQYJ KoZIhvcNAQEFBQADggEBACv0niZSmW+psB1sJXULh3mecDbN2mj0bFpN1YNdjcV7BiOLJ1Rs1ibV f13h73z8C7SBsPXTM5si8gmJtOnXM5jsgtlql44h/RrjUr8+mtK5DPCZls9J7iz3cGthzwOPvxUj nMSv3BpRX5oJom5ESgCM9Nn4u/ECTlLMhEIOYnBFiN0eDxcxz+r1cpbHg3r0otIKyxLpeaCjP6AH F93EHp4T8Rb63y3CcDgxrQGHlTdVi3QvxaMUexUXD81fiA+UqsB/MKmRxB1Hs4Vf3Q/+ejcm78K1 ROF8TNPmNWRlKg3Y7cSFjZGzLuzXsvSsCbw4HLn0oZe/OfgSbarTAxttL5IxggHRMIIBzQIBATBL MEYxFzAVBgNVBAMMDldlc3RvbiBBZGFtc29uMQswCQYDVQQGEwJVUzEeMBwGCSqGSIb3DQEJARYP ZHJvc0BuZXRhcHAuY29tAgEBMAkGBSsOAwIaBQCgXTAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcB MBwGCSqGSIb3DQEJBTEPFw0xMjA1MTYyMjEwNTdaMCMGCSqGSIb3DQEJBDEWBBT+DARl9Gg3T1MA KvYXR7FBet4UczANBgkqhkiG9w0BAQEFAASCAQAFKt/y+ddhn0poOV32pu7NS/PfGqmpeds0uMK9 VfLcf6+LMdvB22k+pFbi9C2eIRvkHV6DxH1OYNzYKNkx3U7do3Vg3PSVenkHS0aBYpOgEremV9tR jZD7Ap/xaPDsl5cbwj+jcAihC8AWinHZ+anKSr0P/tm92SMI4uCFIoQ4iNvIgo4Ty9pTIcektxFF O6f9pXN/b+ADHpktRT4tW0JYC1bLvz0TZIF/hz9r4HvOofq1Eu0rKWMLXRXU5ijMvSuAcMidnlRh WPwii/qPikkp+HvDFxMJuPcxSUv0YZCzzjZtLqq21268sVjIzIJ1+6jget24P5ZynkL/XKK5D410 AAAAAAAA --Apple-Mail=_F523182B-B871-467B-A73A-93525A12C987--