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 5FD55C433F5 for ; Tue, 1 Mar 2022 04:29:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232385AbiCAEaN (ORCPT ); Mon, 28 Feb 2022 23:30:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231911AbiCAE3w (ORCPT ); Mon, 28 Feb 2022 23:29:52 -0500 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 183784DF4E; Mon, 28 Feb 2022 20:29:09 -0800 (PST) Received: from linux.localdomain (unknown [113.200.148.30]) by mail.loongson.cn (Coremail) with SMTP id AQAAf9Bx4M4NoR1iUhoAAA--.595S3; Tue, 01 Mar 2022 12:29:02 +0800 (CST) From: Tiezhu Yang To: Thomas Bogendoerfer , Mike Rapoport , Andrew Morton Cc: Xuefeng Li , linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 1/4] MIPS: Refactor early_parse_mem() to fix mem= parameter Date: Tue, 1 Mar 2022 12:28:58 +0800 Message-Id: <1646108941-27919-2-git-send-email-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1646108941-27919-1-git-send-email-yangtiezhu@loongson.cn> References: <1646108941-27919-1-git-send-email-yangtiezhu@loongson.cn> X-CM-TRANSID: AQAAf9Bx4M4NoR1iUhoAAA--.595S3 X-Coremail-Antispam: 1UD129KBjvJXoW7Zr15JF17tFyUXF1rCFyrCrg_yoW5JFW5pw 4fZw1fKr48JFnrZayIyrn3Zry5Gw1vkFW3XFW2kr95Z3WUCr17Cr1IqrW2gFy2qrWxJ3W2 qF1ktFyjganFy3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBa14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r1I6r4UM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l84 ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkIecxEwVAFwVW8XwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAI cVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2js IEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JU4q2_UUUUU= X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to Documentation/admin-guide/kernel-parameters.txt, the kernel command-line parameter mem= means "Force usage of a specific amount of memory", but when add "mem=3G" to the command-line, kernel boot hangs in sparse_init(). This commit is similar with the implementation of the other archs such as arm64, powerpc and riscv, refactor the function early_parse_mem() and then use memblock_enforce_memory_limit() to limit the memory size. With this patch, when add "mem=3G" to the command-line, the kernel boots successfully, we can see the following messages: [ 0.000000] Memory limited to 3072MB ... [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000000200000-0x000000000effffff] [ 0.000000] node 0: [mem 0x0000000090200000-0x00000000ffffffff] [ 0.000000] node 0: [mem 0x0000000120000000-0x00000001613fffff] ... [ 0.000000] Memory: 3005280K/3145728K available (...) After login, the output of free command is consistent with the above log. Signed-off-by: Tiezhu Yang --- arch/mips/kernel/setup.c | 26 +++++++++----------------- 1 file changed, 9 insertions(+), 17 deletions(-) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index f979adf..50396ba 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -339,27 +339,15 @@ static void __init bootmem_init(void) #endif /* CONFIG_SGI_IP27 */ static int usermem __initdata; +static phys_addr_t memory_limit; static int __init early_parse_mem(char *p) { - phys_addr_t start, size; - - /* - * If a user specifies memory size, we - * blow away any automatically generated - * size. - */ - if (usermem == 0) { - usermem = 1; - memblock_remove(memblock_start_of_DRAM(), - memblock_end_of_DRAM() - memblock_start_of_DRAM()); - } - start = 0; - size = memparse(p, &p); - if (*p == '@') - start = memparse(p + 1, &p); + if (!p) + return 1; - memblock_add(start, size); + memory_limit = memparse(p, &p) & PAGE_MASK; + pr_notice("Memory limited to %lluMB\n", (u64)memory_limit >> 20); return 0; } @@ -678,6 +666,10 @@ static void __init arch_mem_init(char **cmdline_p) memblock_reserve(__pa_symbol(&__nosave_begin), __pa_symbol(&__nosave_end) - __pa_symbol(&__nosave_begin)); + /* Limit the memory. */ + memblock_enforce_memory_limit(memory_limit); + memblock_allow_resize(); + early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn)); } -- 2.1.0