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=-6.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS autolearn=no 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 8857AC07E99 for ; Fri, 9 Jul 2021 22:33:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 70076613C2 for ; Fri, 9 Jul 2021 22:33:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231276AbhGIWgC (ORCPT ); Fri, 9 Jul 2021 18:36:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:53974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229542AbhGIWgB (ORCPT ); Fri, 9 Jul 2021 18:36:01 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BFCA4613B0; Fri, 9 Jul 2021 22:33:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1625869996; bh=vB6UUDCayTxmA7o4zqOKFTp2vJ9b5CMA+bhTA3+T6UY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=oIhUGKASaH0OdOwF/jv5ekgOeIjfDYZ4SnnN43ojN2s7HF2+TkRCDxTG4tSwWzwN1 PidrWQdd+CRTVHnLi5TAImaovQJ6KRAnnbzDyhb80y/hQARBuWd6cfAjx/np8C6S0F o9lKhO5RnWM5z6oC6UQ0Y2BtROjGmca7lB+3lKVQ= Date: Fri, 9 Jul 2021 15:33:16 -0700 From: Andrew Morton To: Yang Huan Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel@vivo.com, syzbot+b07d8440edb5f8988eea@syzkaller.appspotmail.com, Wang Qing Subject: Re: [PATCH] mm/page_alloc: fix alloc_pages_bulk/set_page_owner panic on irq disabled Message-Id: <20210709153316.a81214a453920dbcc2714ae6@linux-foundation.org> In-Reply-To: <20210709090600.9804-1-link@vivo.com> References: <20210709090600.9804-1-link@vivo.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 9 Jul 2021 17:05:59 +0800 Yang Huan wrote: > The problem is caused by set_page_owner alloc memory to save stack with > GFP_KERNEL in local_riq disabled. > So, we just can't assume that alloc flags should be same with new page, > let's split it. But in most situation, same is ok, in alloc_pages_bulk, > input GFP_ATOMIC when prep_new_pages Please more fully describe the bug which is being fixed. A link to the sysbot report would be helpful. I assume there was a stack backtrace available? Seeing the will help others to understand the bug. And if you are able to identify the patch which introduced the bug, a Fixes: tag would be helpful as well. Thanks.