From patchwork Thu Oct 14 17:59:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 12559177 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8041AC4332F for ; Thu, 14 Oct 2021 17:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6526B61152 for ; Thu, 14 Oct 2021 17:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231503AbhJNSBN (ORCPT ); Thu, 14 Oct 2021 14:01:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:59871 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229718AbhJNSBM (ORCPT ); Thu, 14 Oct 2021 14:01:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634234347; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GVJvKnAoK21JZkJlCWiIrcRBgTaMqs7HQ0BrYyZO1FA=; b=H/Y+bJDSEGUM43EttPMd2vIFsilVOwXPgPll+wOlCSeW76wW7T5KtWQA/vpIkZ275MVlAe fFZvIsfw156IRdArtoyfwzTOYJZRbRKrrGa/cTcTRGpWycWmq1aPW6TPQtQmkDPT5K4Wzk TK0EK8JaoQPIn8RJb9ayT1cAF1+I89Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-466-ZqRHA6wINAul5XgeUOiEKg-1; Thu, 14 Oct 2021 13:59:05 -0400 X-MC-Unique: ZqRHA6wINAul5XgeUOiEKg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 03B691006AB1 for ; Thu, 14 Oct 2021 17:59:05 +0000 (UTC) Received: from bfoster.redhat.com (unknown [10.22.8.90]) by smtp.corp.redhat.com (Postfix) with ESMTP id B6EBBB8549 for ; Thu, 14 Oct 2021 17:59:04 +0000 (UTC) From: Brian Foster To: linux-xfs@vger.kernel.org Subject: [PATCH v3 3/4] xfs: terminate perag iteration reliably on agcount Date: Thu, 14 Oct 2021 13:59:01 -0400 Message-Id: <20211014175902.1519172-4-bfoster@redhat.com> In-Reply-To: <20211014175902.1519172-1-bfoster@redhat.com> References: <20211014175902.1519172-1-bfoster@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org The for_each_perag_from() iteration macro relies on sb_agcount to process every perag currently within EOFS from a given starting point. It's perfectly valid to have perag structures beyond sb_agcount, however, such as if a growfs is in progress. If a perag loop happens to race with growfs in this manner, it will actually attempt to process the post-EOFS perag where ->pag_agno == sb_agcount. This is reproduced by xfs/104 and manifests as the following assert failure in superblock write verifier context: XFS: Assertion failed: agno < mp->m_sb.sb_agcount, file: fs/xfs/libxfs/xfs_types.c, line: 22 Update the corresponding macro to only process perags that are within the current sb_agcount. Fixes: 58d43a7e3263 ("xfs: pass perags around in fsmap data dev functions") Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_ag.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h index 134e8635dee1..4585ebb3f450 100644 --- a/fs/xfs/libxfs/xfs_ag.h +++ b/fs/xfs/libxfs/xfs_ag.h @@ -142,7 +142,7 @@ xfs_perag_next( (pag) = xfs_perag_next((pag), &(agno))) #define for_each_perag_from(mp, agno, pag) \ - for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount, (pag)) + for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag)) #define for_each_perag(mp, agno, pag) \