From patchwork Wed Jun 30 06:14:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Chinner X-Patchwork-Id: 12351271 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 5301EC11F6B for ; Wed, 30 Jun 2021 06:14:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DF0E561D01 for ; Wed, 30 Jun 2021 06:14:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF0E561D01 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=fromorbit.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 703958D017C; Wed, 30 Jun 2021 02:14:38 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6D94A8D017A; Wed, 30 Jun 2021 02:14:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3FFF98D017A; Wed, 30 Jun 2021 02:14:38 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0211.hostedemail.com [216.40.44.211]) by kanga.kvack.org (Postfix) with ESMTP id 0C4458D017A for ; Wed, 30 Jun 2021 02:14:38 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id CF331181B949F for ; Wed, 30 Jun 2021 06:14:37 +0000 (UTC) X-FDA: 78309376194.05.B87ECDB Received: from mail105.syd.optusnet.com.au (mail105.syd.optusnet.com.au [211.29.132.249]) by imf10.hostedemail.com (Postfix) with ESMTP id 122DE6002088 for ; Wed, 30 Jun 2021 06:14:36 +0000 (UTC) Received: from dread.disaster.area (pa49-179-138-183.pa.nsw.optusnet.com.au [49.179.138.183]) by mail105.syd.optusnet.com.au (Postfix) with ESMTPS id 6C7E71044EBF; Wed, 30 Jun 2021 16:14:35 +1000 (AEST) Received: from discord.disaster.area ([192.168.253.110]) by dread.disaster.area with esmtp (Exim 4.92.3) (envelope-from ) id 1lyTUY-0012JJ-JS; Wed, 30 Jun 2021 16:14:34 +1000 Received: from dave by discord.disaster.area with local (Exim 4.94) (envelope-from ) id 1lyTUY-007LTq-Bh; Wed, 30 Jun 2021 16:14:34 +1000 From: Dave Chinner To: linux-xfs@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 1/3] mm: Add kvrealloc() Date: Wed, 30 Jun 2021 16:14:29 +1000 Message-Id: <20210630061431.1750745-2-david@fromorbit.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210630061431.1750745-1-david@fromorbit.com> References: <20210630061431.1750745-1-david@fromorbit.com> MIME-Version: 1.0 X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.3 cv=YKPhNiOx c=1 sm=1 tr=0 a=MnllW2CieawZLw/OcHE/Ng==:117 a=MnllW2CieawZLw/OcHE/Ng==:17 a=r6YtysWOX24A:10 a=20KFwNOVAAAA:8 a=FgU_YNmxFDRv79IIi3MA:9 Authentication-Results: imf10.hostedemail.com; dkim=none; spf=none (imf10.hostedemail.com: domain of david@fromorbit.com has no SPF policy when checking 211.29.132.249) smtp.mailfrom=david@fromorbit.com; dmarc=none X-Stat-Signature: 8psyymmk3qfh48haquku4mkx19rp5wdt X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 122DE6002088 X-HE-Tag: 1625033676-147122 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Dave Chinner During log recovery of an XFS filesystem with 64kB directory buffers, rebuilding a buffer split across two log records results in a memory allocation warning from krealloc like this: xfs filesystem being mounted at /mnt/scratch supports timestamps until 2038 (0x7fffffff) XFS (dm-0): Unmounting Filesystem XFS (dm-0): Mounting V5 Filesystem XFS (dm-0): Starting recovery (logdev: internal) ------------[ cut here ]------------ WARNING: CPU: 5 PID: 3435170 at mm/page_alloc.c:3539 get_page_from_freelist+0xdee/0xe40 ..... RIP: 0010:get_page_from_freelist+0xdee/0xe40 Call Trace: ? complete+0x3f/0x50 __alloc_pages+0x16f/0x300 alloc_pages+0x87/0x110 kmalloc_order+0x2c/0x90 kmalloc_order_trace+0x1d/0x90 __kmalloc_track_caller+0x215/0x270 ? xlog_recover_add_to_cont_trans+0x63/0x1f0 krealloc+0x54/0xb0 xlog_recover_add_to_cont_trans+0x63/0x1f0 xlog_recovery_process_trans+0xc1/0xd0 xlog_recover_process_ophdr+0x86/0x130 xlog_recover_process_data+0x9f/0x160 xlog_recover_process+0xa2/0x120 xlog_do_recovery_pass+0x40b/0x7d0 ? __irq_work_queue_local+0x4f/0x60 ? irq_work_queue+0x3a/0x50 xlog_do_log_recovery+0x70/0x150 xlog_do_recover+0x38/0x1d0 xlog_recover+0xd8/0x170 xfs_log_mount+0x181/0x300 xfs_mountfs+0x4a1/0x9b0 xfs_fs_fill_super+0x3c0/0x7b0 get_tree_bdev+0x171/0x270 ? suffix_kstrtoint.constprop.0+0xf0/0xf0 xfs_fs_get_tree+0x15/0x20 vfs_get_tree+0x24/0xc0 path_mount+0x2f5/0xaf0 __x64_sys_mount+0x108/0x140 do_syscall_64+0x3a/0x70 entry_SYSCALL_64_after_hwframe+0x44/0xae Essentially, we are taking a multi-order allocation from kmem_alloc() (which has an open coded no fail, no warn loop) and then reallocating it out to 64kB using krealloc(__GFP_NOFAIL) and that is then triggering the above warning. This is a regression caused by converting this code from an open coded no fail/no warn reallocation loop to using __GFP_NOFAIL. What we actually need here is kvrealloc(), so that if contiguous page allocation fails we fall back to vmalloc() and we don't get nasty warnings happening in XFS. Fixes: 771915c4f688 ("xfs: remove kmem_realloc()") Signed-off-by: Dave Chinner --- fs/xfs/xfs_log_recover.c | 2 +- include/linux/mm.h | 2 ++ mm/util.c | 15 +++++++++++++++ 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 1721fce2ec94..fee4fbadea0a 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -2062,7 +2062,7 @@ xlog_recover_add_to_cont_trans( old_ptr = item->ri_buf[item->ri_cnt-1].i_addr; old_len = item->ri_buf[item->ri_cnt-1].i_len; - ptr = krealloc(old_ptr, len + old_len, GFP_KERNEL | __GFP_NOFAIL); + ptr = kvrealloc(old_ptr, old_len, len + old_len, GFP_KERNEL); memcpy(&ptr[old_len], dp, len); item->ri_buf[item->ri_cnt-1].i_len += len; item->ri_buf[item->ri_cnt-1].i_addr = ptr; diff --git a/include/linux/mm.h b/include/linux/mm.h index 8ae31622deef..aa720bc0a1d0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -827,6 +827,8 @@ static inline void *kvcalloc(size_t n, size_t size, gfp_t flags) return kvmalloc_array(n, size, flags | __GFP_ZERO); } +extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize, + gfp_t flags); extern void kvfree(const void *addr); extern void kvfree_sensitive(const void *addr, size_t len); diff --git a/mm/util.c b/mm/util.c index a8bf17f18a81..1104339ad2ca 100644 --- a/mm/util.c +++ b/mm/util.c @@ -635,6 +635,21 @@ void kvfree_sensitive(const void *addr, size_t len) } EXPORT_SYMBOL(kvfree_sensitive); +void *kvrealloc(const void *p, size_t oldsize, size_t newsize, gfp_t flags) +{ + void *newp; + + if (oldsize >= newsize) + return (void *)p; + newp = kvmalloc(newsize, flags); + if (!newp) + return NULL; + memcpy(newp, p, oldsize); + kvfree(p); + return newp; +} +EXPORT_SYMBOL(kvrealloc); + static inline void *__page_rmapping(struct page *page) { unsigned long mapping;