From patchwork Fri Sep 23 10:38:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Westphal X-Patchwork-Id: 12986426 X-Patchwork-Delegate: kuba@kernel.org 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1B3EC6FA86 for ; Fri, 23 Sep 2022 10:39:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231639AbiIWKjR (ORCPT ); Fri, 23 Sep 2022 06:39:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231645AbiIWKjO (ORCPT ); Fri, 23 Sep 2022 06:39:14 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD7B112EDA0; Fri, 23 Sep 2022 03:39:13 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1obg5L-0004UW-7n; Fri, 23 Sep 2022 12:39:07 +0200 From: Florian Westphal To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, vbabka@suse.cz, mhocko@suse.com, akpm@linux-foundation.org, urezki@gmail.com, , , Florian Westphal , Martin Zaharinov Subject: [PATCH mm] mm: fix BUG with kvzalloc+GFP_ATOMIC Date: Fri, 23 Sep 2022 12:38:58 +0200 Message-Id: <20220923103858.26729-1-fw@strlen.de> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Martin Zaharinov reports BUG() in mm land for 5.19.10 kernel: kernel BUG at mm/vmalloc.c:2437! invalid opcode: 0000 [#1] SMP CPU: 28 PID: 0 Comm: swapper/28 Tainted: G W O 5.19.9 #1 [..] RIP: 0010:__get_vm_area_node+0x120/0x130 __vmalloc_node_range+0x96/0x1e0 kvmalloc_node+0x92/0xb0 bucket_table_alloc.isra.0+0x47/0x140 rhashtable_try_insert+0x3a4/0x440 rhashtable_insert_slow+0x1b/0x30 [..] bucket_table_alloc uses kvzallocGPF_ATOMIC). If kmalloc fails, this now falls through to vmalloc and hits code paths that assume GFP_KERNEL. Revert the problematic change and stay with slab allocator. Reported-by: Martin Zaharinov Fixes: a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc") Cc: Michal Hocko Link: https://lore.kernel.org/netdev/09BE0B8A-3ADF-458E-B75E-931B74996355@gmail.com/T/#u Signed-off-by: Florian Westphal --- mm/util.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/util.c b/mm/util.c index c9439c66d8cf..ba7fe1cb6846 100644 --- a/mm/util.c +++ b/mm/util.c @@ -593,6 +593,13 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node) gfp_t kmalloc_flags = flags; void *ret; + /* + * vmalloc uses GFP_KERNEL for some internal allocations (e.g page tables) + * so the given set of flags has to be compatible. + */ + if ((flags & GFP_KERNEL) != GFP_KERNEL) + return kmalloc_node(size, flags, node); + /* * We want to attempt a large physically contiguous block first because * it is less likely to fragment multiple larger blocks and therefore