From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) (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 CE4791607B9 for ; Mon, 22 Jul 2024 07:49:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.255 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721634597; cv=none; b=Jok4vFoqm/LabW2cVNQW4m65qL7spFNGykVG0NRIPepBbXOCriMz9MqnzvBtChVnjSxweuPzPS4+j4fbmA5PX9eA7QUYcO+K3m5Mt+/MKhURom0NH6e/hL1SAnuI2N9qoUUbNxjfB6RoSCJwuXH1i+LNEItOGDxj5e2QicJNyx0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721634597; c=relaxed/simple; bh=qWES6iMMiupLxaKVo0bUbt2asytFgSHzI/pv7kIz6AQ=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=N9pY1gczV1O4CwxCicF6AltkDyL+JKOCl/1z2YfIpwjES/OOLZoG0sHPNJVjJ5uSPaXbEyd2T80YRNbIXACyZIxIhvZlb+u6tONZ5YmuiNIUa8s3xmlhFdkKVrSeij52Ch2+sSfLfXuDTshSjqxJYPGf2ZqpV8gCVxDV4oVr90c= 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=45.249.212.255 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 [172.19.88.194]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4WSC3l6QmQz1JDK2; Mon, 22 Jul 2024 15:44:51 +0800 (CST) Received: from kwepemi100008.china.huawei.com (unknown [7.221.188.57]) by mail.maildlp.com (Postfix) with ESMTPS id 16FC31402CE; Mon, 22 Jul 2024 15:49:50 +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 15:49:48 +0800 Message-ID: Date: Mon, 22 Jul 2024 15:49:47 +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> <5816d4d5-e038-c90b-5ac2-1a3b3a8b9e46@huawei.com> From: Jinjie Ruan In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemi100008.china.huawei.com (7.221.188.57) On 2024/7/22 15:23, Mike Rapoport wrote: > On Mon, Jul 22, 2024 at 03:08:29PM +0800, Jinjie Ruan wrote: >> >> >> 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; >> > > Why no simply > > diff --git a/kernel/crash_reserve.c b/kernel/crash_reserve.c > index 5b2722a93a48..64312709877d 100644 > --- a/kernel/crash_reserve.c > +++ b/kernel/crash_reserve.c > @@ -336,6 +336,9 @@ int __init parse_crashkernel(char *cmdline, > if (!*crash_size) > ret = -EINVAL; > > + if (*crash_size >= system_ram) > + ret = -EINVAL; > + > return ret; This is good, thank you! > } > > >>> >>>> reserve_crashkernel_generic(cmdline, crash_size, crash_base, >>>> low_size, high); >>>> } >>>> -- >>>> 2.34.1 >>>> >>> >