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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B56B0C43334 for ; Thu, 9 Jun 2022 04:43:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237250AbiFIEnI (ORCPT ); Thu, 9 Jun 2022 00:43:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237848AbiFIEnF (ORCPT ); Thu, 9 Jun 2022 00:43:05 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98F2D22369E; Wed, 8 Jun 2022 21:43:03 -0700 (PDT) Received: from dggpemm500022.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4LJWf26nYGzjX3f; Thu, 9 Jun 2022 12:42:02 +0800 (CST) Received: from dggpemm500001.china.huawei.com (7.185.36.107) by dggpemm500022.china.huawei.com (7.185.36.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 9 Jun 2022 12:43:01 +0800 Received: from [10.174.177.243] (10.174.177.243) by dggpemm500001.china.huawei.com (7.185.36.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 9 Jun 2022 12:43:00 +0800 Message-ID: <6763271f-6f65-b83a-6892-dbd502368f5e@huawei.com> Date: Thu, 9 Jun 2022 12:43:00 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [next] arm64: boot failed - next-20220606 Content-Language: en-US From: Kefeng Wang To: Vasily Averin , Naresh Kamboju , Shakeel Butt , Linux ARM CC: Stephen Rothwell , Linux-Next Mailing List , open list , , , linux-mm , Andrew Morton , "Ard Biesheuvel" , Arnd Bergmann , Catalin Marinas , Raghuram Thammiraju , Mark Brown , Will Deacon , "Roman Gushchin" , Qian Cai References: <20220607162504.7fd5a92a@canb.auug.org.au> <2a4cc632-c936-1e42-4fdc-572334c58ee1@openvz.org> <44530040-0384-796e-143f-b7293886753c@huawei.com> In-Reply-To: <44530040-0384-796e-143f-b7293886753c@huawei.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm500001.china.huawei.com (7.185.36.107) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/6/9 11:44, Kefeng Wang wrote: > > On 2022/6/9 10:49, Vasily Averin wrote: >> Dear ARM developers, >> could you please help me to find the reason of this problem? > Hi, >> mem_cgroup_from_obj(): >> ffff80000836cf40:       d503245f        bti     c >> ffff80000836cf44:       d503201f        nop >> ffff80000836cf48:       d503201f        nop >> ffff80000836cf4c:       d503233f        paciasp >> ffff80000836cf50:       d503201f        nop >> ffff80000836cf54:       d2e00021        mov     x1, >> #0x1000000000000            // #281474976710656 >> ffff80000836cf58:       8b010001        add     x1, x0, x1 >> ffff80000836cf5c:       b25657e4        mov     x4, >> #0xfffffc0000000000         // #-4398046511104 >> ffff80000836cf60:       d34cfc21        lsr     x1, x1, #12 >> ffff80000836cf64:       d37ae421        lsl     x1, x1, #6 >> ffff80000836cf68:       8b040022        add     x2, x1, x4 >> ffff80000836cf6c:       f9400443        ldr     x3, [x2, #8] >> >> x5 : ffff80000a96f000 x4 : fffffc0000000000 x3 : ffff80000ad5e680 >> x2 : fffffe00002bc240 x1 : 00000200002bc240 x0 : ffff80000af09740 >> >> x0 = 0xffff80000af09740 is an argument of mem_cgroup_from_obj() >> according to System.map it is init_net >> >> This issue is caused by calling virt_to_page() on address of static >> variable init_net. >> Arm64 consider that addresses of static variables are not valid >> virtual addresses. >> On x86_64 the same API works without any problem. >> >> Unfortunately I do not understand the cause of the problem. >> I do not see any bugs in my patch. >> I'm using an existing API, mem_cgroup_from_obj(), to find the memory >> cgroup used >> to account for the specified object. >> In particular, in the current case, I wanted to get the memory cgroup >> of the >> specified network namespace by the name taken from for_each_net(). >> The first object in this list is the static structure unit_net > > root@test:~# cat /proc/kallsyms |grep -w _data > ffff80000a110000 D _data > root@test:~# cat /proc/kallsyms |grep -w _end > ffff80000a500000 B _end > root@test:~# cat /proc/kallsyms |grep -w init_net > ffff80000a4eb980 B init_net > > the init_net is located in data section, on arm64, it is allowed by > vmalloc, see > >     map_kernel_segment(pgdp, _data, _end, PAGE_KERNEL, &vmlinux_data, > 0, 0); > > and the arm has same behavior. > > We could let init_net be allocated dynamically, but I think it could > change a lot. > > Any better sugguestion, Catalin? or  add vmalloc check in mem_cgroup_from_obj()? diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 27cebaa53472..fb817e5da5f0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2860,7 +2860,10 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)         if (mem_cgroup_disabled())                 return NULL; -       folio = virt_to_folio(p); +       if (unlikely(is_vmalloc_addr(p))) +               folio = page_folio(vmalloc_to_page(p)); +       else +               folio = virt_to_folio(p);         /*          * Slab objects are accounted individually, not per-page.