From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC443DF51 for ; Mon, 22 Jul 2024 07:08:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.187 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721632118; cv=none; b=uVgjYttU9cbAVeN2TN+qwPp01UDZ/KiBc9femEEQDIjW4S3Js0LnSlbgVXbszK60kFGrvcB4+4Y8Li0zzfaCiGd7WRgUnCmd5g977ahL2mQ821q2exwhQ2He4N3BVtM1fxosFSV1vvlGHyXSsK82/j9yYwXYgC0zD6r9Emd7wjs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721632118; c=relaxed/simple; bh=zR0fiIg21DFh/exHdAf9KRFt3nu7sGyvhkwqQpW1Zdk=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=VgyASaQiEVSfijItl0+mdQbHR72tScReIipH5XgodJ18Ml+SOcuC09/eHkfya8RNGt6sJ2Xege9SSm2BW1G7pZ/9jAZaI6J38SssRlfwCCAbuAQnGGGKce2QSYre5PyisyDfRkFwU1kqC2qmmf982XUAMyu/AS9kjTluPIcfqD8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.174]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4WSB860gDrzxTgY; Mon, 22 Jul 2024 15:03:34 +0800 (CST) Received: from kwepemi100008.china.huawei.com (unknown [7.221.188.57]) by mail.maildlp.com (Postfix) with ESMTPS id 63AF4140427; Mon, 22 Jul 2024 15:08:32 +0800 (CST) Received: from [10.67.109.254] (10.67.109.254) by kwepemi100008.china.huawei.com (7.221.188.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Mon, 22 Jul 2024 15:08:31 +0800 Message-ID: <5816d4d5-e038-c90b-5ac2-1a3b3a8b9e46@huawei.com> Date: Mon, 22 Jul 2024 15:08:29 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.2.0 Subject: Re: [PATCH v4 3/3] riscv: kdump: Fix crash memory reserve exceed system memory bug Content-Language: en-US To: Mike Rapoport CC: , , , , , , , , , , , , , , , , , , , , , , , , , References: <20240722035701.696874-1-ruanjinjie@huawei.com> <20240722035701.696874-4-ruanjinjie@huawei.com> From: Jinjie Ruan In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemi100008.china.huawei.com (7.221.188.57) On 2024/7/22 14:38, Mike Rapoport wrote: > Hi, > > On Mon, Jul 22, 2024 at 11:57:01AM +0800, Jinjie Ruan wrote: >> Similar with x86_32, on Riscv32 Qemu "virt" machine with 1GB memory, the >> crash kernel "crashkernel=4G" is ok as below: >> crashkernel reserved: 0x00000000bf400000 - 0x00000001bf400000 (4096 MB) >> >> The cause is that the crash_size is parsed and printed with "unsigned long >> long" data type which is 8 bytes but allocated used with "phys_addr_t" >> which is 4 bytes in memblock_phys_alloc_range(). >> >> Fix it by checking if the crash_size is greater than system RAM size and >> warn out as parse_crashkernel_mem() do it if so. >> >> After this patch, it fails and there is no above confusing reserve >> success info. >> >> Signed-off-by: Jinjie Ruan >> --- >> arch/riscv/mm/init.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c >> index bfa2dea95354..5d66a4937fcd 100644 >> --- a/arch/riscv/mm/init.c >> +++ b/arch/riscv/mm/init.c >> @@ -1381,6 +1381,11 @@ static void __init arch_reserve_crashkernel(void) >> if (ret) >> return; >> >> + if (crash_size >= memblock_phys_mem_size()) { >> + pr_warn("Crashkernel: invalid size."); >> + return; >> + } >> + > > What the point of adding three identical checks right after the call to > parse_crashkernel()? > > This check should be there and parse_crashkernel() should return error in > this case. Hi, Mike How about the folling rough patch? --- a/kernel/crash_reserve.c +++ b/kernel/crash_reserve.c @@ -313,7 +313,7 @@ int __init parse_crashkernel(char *cmdline, if (high && ret == -ENOENT) { ret = __parse_crashkernel(cmdline, 0, crash_size, crash_base, suffix_tbl[SUFFIX_HIGH]); - if (ret || !*crash_size) + if (ret || !*crash_size || crash_size >= system_ram) return -EINVAL; /* @@ -332,7 +332,7 @@ int __init parse_crashkernel(char *cmdline, *high = true; } #endif - if (!*crash_size) + if (!*crash_size || crash_size >= system_ram) ret = -EINVAL; > >> reserve_crashkernel_generic(cmdline, crash_size, crash_base, >> low_size, high); >> } >> -- >> 2.34.1 >> >