From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 126F4C4727D for ; Tue, 22 Sep 2020 17:05:35 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7375920739 for ; Tue, 22 Sep 2020 17:05:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="XEoWL0Et" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7375920739 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id C9C0714F278EF; Tue, 22 Sep 2020 10:05:33 -0700 (PDT) Received-SPF: None (mailfrom) identity=mailfrom; client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=willy@infradead.org; receiver= Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 0D50E14F278EC for ; Tue, 22 Sep 2020 10:05:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ofr4ycOkQnFAciMKQaMH/OLH5o4G6m4xVeFOeH1Pf8k=; b=XEoWL0EtfRYmAwbOKKCLbqyj3d aad4hP2RYYM35/Qd3cvIrLQjfc4bFUJ40ZYOCm36Y6MPZbQlM10p98SR2XAm0SC2oy65LLGSRgOhs e/iB335z/XX20W6Ju5qOm0WNQ3qRY9ba6/lrjphBDsd9+xJpkXgTGygfFM6l3AStrXFnQh5EMLRvC U4m+HyXSumF8/K5QlgI080CHAa4pBfYrvU4WWR+yEAtWyqDmzOOmlCVIGgwrVyXyFgyXcU9Ca2uOA i7lBTg4mLyjU2cA7xKE+3bIQCBBXhOUzFNTozSiySeeCZJTTdIakYj0tCW9GKj0ZXSo9CFg+/WNZN vR6PNQDA==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKljK-0002Na-Gp; Tue, 22 Sep 2020 17:05:26 +0000 Date: Tue, 22 Sep 2020 18:05:26 +0100 From: Matthew Wilcox To: Qian Cai Subject: Re: [PATCH v2 5/9] iomap: Support arbitrarily many blocks per page Message-ID: <20200922170526.GK32101@casper.infradead.org> References: <20200910234707.5504-1-willy@infradead.org> <20200910234707.5504-6-willy@infradead.org> <163f852ba12fd9de5dec7c4a2d6b6c7cdb379ebc.camel@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <163f852ba12fd9de5dec7c4a2d6b6c7cdb379ebc.camel@redhat.com> Message-ID-Hash: HCR67LJ7V5XEFWUWNXWD7NQJ2GV3T7VC X-Message-ID-Hash: HCR67LJ7V5XEFWUWNXWD7NQJ2GV3T7VC X-MailFrom: willy@infradead.org X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, "Darrick J . Wong" , Christoph Hellwig , linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, Dave Kleikamp , jfs-discussion@lists.sourceforge.net, Dave Chinner , Stephen Rothwell , linux-next@vger.kernel.org X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Tue, Sep 22, 2020 at 12:23:45PM -0400, Qian Cai wrote: > On Fri, 2020-09-11 at 00:47 +0100, Matthew Wilcox (Oracle) wrote: > > Size the uptodate array dynamically to support larger pages in the > > page cache. With a 64kB page, we're only saving 8 bytes per page today, > > but with a 2MB maximum page size, we'd have to allocate more than 4kB > > per page. Add a few debugging assertions. > > > > Signed-off-by: Matthew Wilcox (Oracle) > > Reviewed-by: Dave Chinner > > Some syscall fuzzing will trigger this on powerpc: > > .config: https://gitlab.com/cailca/linux-mm/-/blob/master/powerpc.config > > [ 8805.895344][T445431] WARNING: CPU: 61 PID: 445431 at fs/iomap/buffered-io.c:78 iomap_page_release+0x250/0x270 Well, I'm glad it triggered. That warning is: WARN_ON_ONCE(bitmap_full(iop->uptodate, nr_blocks) != PageUptodate(page)); so there was definitely a problem of some kind. truncate_cleanup_page() calls do_invalidatepage() calls iomap_invalidatepage() calls iomap_page_release() Is this the first warning? I'm wondering if maybe there was an I/O error earlier which caused PageUptodate to get cleared again. If it's easy to reproduce, perhaps you could try something like this? +void dump_iomap_page(struct page *page, const char *reason) +{ + struct iomap_page *iop = to_iomap_page(page); + unsigned int nr_blocks = i_blocks_per_page(page->mapping->host, page); + + dump_page(page, reason); + if (iop) + printk("iop:reads %d writes %d uptodate %*pb\n", + atomic_read(&iop->read_bytes_pending), + atomic_read(&iop->write_bytes_pending), + nr_blocks, iop->uptodate); + else + printk("iop:none\n"); +} and then do something like: if (bitmap_full(iop->uptodate, nr_blocks) != PageUptodate(page)) dump_iomap_page(page, NULL); _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org