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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35847C433EF for ; Wed, 29 Jun 2022 06:30:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BC2AF6B0071; Wed, 29 Jun 2022 02:30:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B72C26B0072; Wed, 29 Jun 2022 02:30:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A61B98E0001; Wed, 29 Jun 2022 02:30:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 96D4D6B0071 for ; Wed, 29 Jun 2022 02:30:47 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay11.hostedemail.com (Postfix) with ESMTP id 7567B811A5 for ; Wed, 29 Jun 2022 06:30:47 +0000 (UTC) X-FDA: 79630300134.18.0AD0F64 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by imf19.hostedemail.com (Postfix) with ESMTP id 4449D1A000E for ; Wed, 29 Jun 2022 06:30:46 +0000 (UTC) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.55]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4LXs3X2wHVz1L8f7; Wed, 29 Jun 2022 14:28:24 +0800 (CST) Received: from dggpemm500001.china.huawei.com (7.185.36.107) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 29 Jun 2022 14:30:40 +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; Wed, 29 Jun 2022 14:30:40 +0800 Message-ID: <9b850fd9-f3a1-265e-7de9-4f6d1e217a0c@huawei.com> Date: Wed, 29 Jun 2022 14:30:39 +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: [PATCH v3] powerpc/memhotplug: Add add_pages override for PPC Content-Language: en-US To: Aneesh Kumar K.V , , CC: , Christophe Leroy References: <20220629050925.31447-1-aneesh.kumar@linux.ibm.com> From: Kefeng Wang In-Reply-To: <20220629050925.31447-1-aneesh.kumar@linux.ibm.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 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656484247; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tmZhHWrpbKnC+FcDgRdeidQrEqoR17gvO9dLhYwO5jE=; b=HiiZXOmDk3Mi29/haPE2ybj3rD/Aw91qxbET+bw0GyO6eqa0h48MNpw9Zl7Asvb166Dvga zvKTi4FMbd1Ws4Q+NtNmqyKdbc+iJo7cyzCBdQ6d7/vrsnJil+Lp5xPT96eHpYNTwiaSI4 KIQNe5cYHivvL6ip9teDhMYAOWXtRrE= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=none; spf=pass (imf19.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656484247; a=rsa-sha256; cv=none; b=gbo3E9JfuRa0zDUAJtRhaSne04LGjGJO4ZTQl2UkQi8CRCtdAFNwZ3nKZqwdKsSUHqGgHj SOj3OdE4vAJye5rSsKD2LpXDAfSHjs8e7ruMKssgVDO2zuet+7xTTw5CznKPKV0fAeWMXc vbx0AcUfxkTh/vjh7edDAfG/rSYnMOY= Authentication-Results: imf19.hostedemail.com; dkim=none; spf=pass (imf19.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-Rspam-User: X-Rspamd-Server: rspam06 X-Stat-Signature: mg7zk4izycydu6x941sy3mcw78pges8i X-Rspamd-Queue-Id: 4449D1A000E X-HE-Tag: 1656484246-902515 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: Hi, On 2022/6/29 13:09, Aneesh Kumar K.V wrote: > With commit ffa0b64e3be5 ("powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit") > the kernel now validate the addr against high_memory value. This results > in the below BUG_ON with dax pfns. > > [ 635.798741][T26531] kernel BUG at mm/page_alloc.c:5521! > 1:mon> e > cpu 0x1: Vector: 700 (Program Check) at [c000000007287630] > pc: c00000000055ed48: free_pages.part.0+0x48/0x110 > lr: c00000000053ca70: tlb_finish_mmu+0x80/0xd0 > sp: c0000000072878d0 > msr: 800000000282b033 > current = 0xc00000000afabe00 > paca = 0xc00000037ffff300 irqmask: 0x03 irq_happened: 0x05 > pid = 26531, comm = 50-landscape-sy > kernel BUG at :5521! > Linux version 5.19.0-rc3-14659-g4ec05be7c2e1 (kvaneesh@ltc-boston8) (gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #625 SMP Thu Jun 23 00:35:43 CDT 2022 > 1:mon> t > [link register ] c00000000053ca70 tlb_finish_mmu+0x80/0xd0 > [c0000000072878d0] c00000000053ca54 tlb_finish_mmu+0x64/0xd0 (unreliable) > [c000000007287900] c000000000539424 exit_mmap+0xe4/0x2a0 > [c0000000072879e0] c00000000019fc1c mmput+0xcc/0x210 > [c000000007287a20] c000000000629230 begin_new_exec+0x5e0/0xf40 > [c000000007287ae0] c00000000070b3cc load_elf_binary+0x3ac/0x1e00 > [c000000007287c10] c000000000627af0 bprm_execve+0x3b0/0xaf0 > [c000000007287cd0] c000000000628414 do_execveat_common.isra.0+0x1e4/0x310 > [c000000007287d80] c00000000062858c sys_execve+0x4c/0x60 > [c000000007287db0] c00000000002c1b0 system_call_exception+0x160/0x2c0 > [c000000007287e10] c00000000000c53c system_call_common+0xec/0x250 > > The fix is to make sure we update high_memory on memory hotplug. > This is similar to what x86 does in commit 3072e413e305 ("mm/memory_hotplug: introduce add_pages") > > Fixes: ffa0b64e3be5 ("powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit") > Cc: Kefeng Wang > Cc: Christophe Leroy > Signed-off-by: Aneesh Kumar K.V > --- > Changes from v2: > * drop WARN_ON_ONCE > * check for error from __add_pages > > arch/powerpc/Kconfig | 4 ++++ > arch/powerpc/mm/mem.c | 33 ++++++++++++++++++++++++++++++++- > 2 files changed, 36 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index c2ce2e60c8f0..7aa12e88c580 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -358,6 +358,10 @@ config ARCH_SUSPEND_NONZERO_CPU > def_bool y > depends on PPC_POWERNV || PPC_PSERIES > > +config ARCH_HAS_ADD_PAGES > + def_bool y > + depends on ARCH_ENABLE_MEMORY_HOTPLUG > + > config PPC_DCR_NATIVE > bool > > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c > index 52b77684acda..a97128a48817 100644 > --- a/arch/powerpc/mm/mem.c > +++ b/arch/powerpc/mm/mem.c > @@ -105,6 +105,37 @@ void __ref arch_remove_linear_mapping(u64 start, u64 size) > vm_unmap_aliases(); > } > > +/* > + * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need > + * updating. > + */ > +static void update_end_of_memory_vars(u64 start, u64 size) > +{ > + unsigned long end_pfn = PFN_UP(start + size); > + > + if (end_pfn > max_pfn) { > + max_pfn = end_pfn; > + max_low_pfn = end_pfn; > + high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; > + } > +} > + > +int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, > + struct mhp_params *params) > +{ > + int ret;                 int ret = -EINVAL; > + > + ret = __add_pages(nid, start_pfn, nr_pages, params); > + if (ret) > + return ret; > + > + /* update max_pfn, max_low_pfn and high_memory */ > + update_end_of_memory_vars(start_pfn << PAGE_SHIFT, > + nr_pages << PAGE_SHIFT); > + > + return ret; > +} > + and could we only call update_end_of_memory_vars() in arch_add_memory()? > int __ref arch_add_memory(int nid, u64 start, u64 size, > struct mhp_params *params) > { > @@ -115,7 +146,7 @@ int __ref arch_add_memory(int nid, u64 start, u64 size, > rc = arch_create_linear_mapping(nid, start, size, params); > if (rc) > return rc; > - rc = __add_pages(nid, start_pfn, nr_pages, params); > + rc = add_pages(nid, start_pfn, nr_pages, params); > if (rc) > arch_remove_linear_mapping(start, size); if (!rc)     update_end_of_memory_vars(start_pfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT); else     arch_remove_linear_mapping(start, size); Thanks > return rc;