From owner-freebsd-bugs@freebsd.org Fri Jan 12 21:49:04 2018 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id EE05DE7E440 for ; Fri, 12 Jan 2018 21:49:04 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.ysv.freebsd.org (mxrelay.ysv.freebsd.org [IPv6:2001:1900:2254:206a::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id BD54A81DE3 for ; Fri, 12 Jan 2018 21:49:04 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.ysv.freebsd.org (Postfix) with ESMTPS id A5D0119B0F for ; Fri, 12 Jan 2018 21:49:04 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id w0CLn48e046476 for ; Fri, 12 Jan 2018 21:49:04 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id w0CLn4fM046475 for freebsd-bugs@FreeBSD.org; Fri, 12 Jan 2018 21:49:04 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 225120] kernel dumps to multi-disk gconcat volumes don't work Date: Fri, 12 Jan 2018 21:49:04 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: markj@FreeBSD.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Jan 2018 21:49:05 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D225120 Bug ID: 225120 Summary: kernel dumps to multi-disk gconcat volumes don't work Product: Base System Version: CURRENT Hardware: Any OS: Any Status: New Severity: Affects Some People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: markj@FreeBSD.org g_concat_kernel_dump() configures kernel dumps to write to the first disk in the request range: 219 for (i =3D 0; i < sc->sc_ndisks; i++) { 220 if (sc->sc_disks[i].d_start <=3D gkd->offset && 221 sc->sc_disks[i].d_end > gkd->offset) 222 break; 223 } When configuring a multi-disk gconcat device as the dump device, this means that we'll never be able to recover kernel dumps. In particular, savecore(8) looks for the trailing kernel dump header in the last sector of the provide= r. Moreover, we can't even easily recover the kernel dump directly from the provider for the first disk, since the last sector of that provider will contain gconcat metadata. (It is possible to use gnop to trim off that last sector, but that's a bit too manual.) I think gconcat (and gmirror) should do what graid does, and implement their own dumper functions which map writes to the corresponding disk(s), instead= of selecting a single disk and passing all writes through to it. This would address this bug and fix the caveat described in the NOTES section of the gmirror man page. --=20 You are receiving this mail because: You are the assignee for the bug.=