From patchwork Thu Nov 3 05:05:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Thomson X-Patchwork-Id: 13029547 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 45F93C433FE for ; Thu, 3 Nov 2022 05:06:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230497AbiKCFGS (ORCPT ); Thu, 3 Nov 2022 01:06:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230460AbiKCFGL (ORCPT ); Thu, 3 Nov 2022 01:06:11 -0400 Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 285ED18B33; Wed, 2 Nov 2022 22:06:08 -0700 (PDT) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.west.internal (Postfix) with ESMTP id 2A554320090D; Thu, 3 Nov 2022 01:06:07 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute2.internal (MEProxy); Thu, 03 Nov 2022 01:06:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fastmail.com.au; h=cc:cc:content-transfer-encoding:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to; s=fm3; t=1667451966; x= 1667538366; bh=QsRVga5tuWe80xx7wDivbwAHLsIWBnEEKFpLl7kgfAE=; b=k FRXCcOi4q6XJqXled46FQOW4d6D/A1Y2h0+8V+qGQ0kv7CRK2hTor0cmf2Y2yqWX UCu9w8kAfdwJGBErfLfLwEaaUpmRq/uQp2Kh27l3IIKbmo4zISSsc2/PnQs59Bk9 ypkfhWUnGJyqxcoUZKFO7aM7dGgCGiP38LpyKVYXVsyMEm2Cw8SNk/0VpwNj+g7l CREXD74iD/x1gbI4veIi/f3d3WpZMJTuk7pTJEeXFxRzh7WuWceABR2PcMUEign6 /SqZZ1M9oUH5wYCAYLQVn8vFhBG8v+zV9YPu6nohbbwuLxQVZ9Bv0HPicQM5Rigu xd/8tyGcE16oasJQ4oA/A== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1667451966; x=1667538366; bh=QsRVga5tuWe80 xx7wDivbwAHLsIWBnEEKFpLl7kgfAE=; b=i5jHDt2JM2TQ+2lbBNoIQfq4wzhHM SU8+rRRuFloLvKAYv+u9dvgy3Mh/bI5RMFHP60ePOI2tDQw/BxbfQTtfuA/PuCxu sUHy7/qiyZ7qu1LxRc6UEWlVyPmwioQzS15uRMvpH4Oo1x7Zssh6Y5aaRD9OTIR+ AZCoTD8Kt6Bb1KRuujdNfuNseDZtFwPkd69RhSxWpDEW5R+U0IJZogObU3XdhMRS NPpS6mzasf4iVjEMUJ7UuzjGbTMYicD2pibA7lDP8AU6MhD1mGXOn26U0ICcS6GN WehJX4eDIMegxD4c5bqX+zHmi6JpCpwywuvOPS1tdqTCLJ/Ee4RP/SHdQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvgedrudekgdejkecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvfevufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeflohhhnhcu vfhhohhmshhonhcuoehgihhtsehjohhhnhhthhhomhhsohhnrdhfrghsthhmrghilhdrtg homhdrrghuqeenucggtffrrghtthgvrhhnpeffteegtddtfedvvdfhieefvddvueevgeeh vdeiffdugeduudduheduhfejkefhveenucffohhmrghinhepkhgvrhhnvghlrdhorhhgne cuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepghhithes jhhohhhnthhhohhmshhonhdrfhgrshhtmhgrihhlrdgtohhmrdgruh X-ME-Proxy: Feedback-ID: ic081425d:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 3 Nov 2022 01:06:03 -0400 (EDT) From: John Thomson To: Sergio Paracuellos , =?utf-8?b?QXLEsW4=?= =?utf-8?b?w6cgw5xOQUw=?= , John Crispin , Thomas Bogendoerfer Cc: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, John Thomson Subject: [RFC PATCH 3/3] mips: ralink: mt7621: do not use kzalloc too early Date: Thu, 3 Nov 2022 15:05:38 +1000 Message-Id: <20221103050538.1930758-4-git@johnthomson.fastmail.com.au> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221103050538.1930758-1-git@johnthomson.fastmail.com.au> References: <20221103050538.1930758-1-git@johnthomson.fastmail.com.au> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Following commit 6edf2576a6cc ("mm/slub: enable debugging memory wasting of kmalloc") mt7621 failed to boot very early, without showing any console messages. This exposed the pre-existing bug of mt7621.c using kzalloc before normal memory management was available. Prior to this slub change, there existed the unintended protection against "kmem_cache *s" being NULL as slab_pre_alloc_hook() happened to return NULL and bailed out of slab_alloc_node(). This allowed mt7621 prom_soc_init to fail in the soc_dev_init kzalloc, but continue booting without this soc device. Console output from a DEBUG_ZBOOT vmlinuz kernel loading, with mm/slub modified to warn on kmem_cache zero or null: zimage at: 80B842A0 810B4BC0 Uncompressing Linux at load address 80001000 Copy device tree to address 80B80EE0 Now, booting the kernel... [ 0.000000] Linux version 6.1.0-rc3+ (john@john) (mipsel-buildroot-linux-gnu-gcc.br_real (Buildroot 2021.11-4428-g6b6741b) 12.2.0, GNU ld (GNU Binutils) 2.39) #73 SMP Wed Nov 2 05:10:01 AEST 2022 [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: CPU: 0 PID: 0 at mm/slub.c:3416 kmem_cache_alloc+0x5a4/0x5e8 [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.1.0-rc3+ #73 [ 0.000000] Stack : 810fff78 80084d98 00000000 00000004 00000000 00000000 80889d04 80c90000 [ 0.000000] 80920000 807bd328 8089d368 80923bd3 00000000 00000001 80889cb0 00000000 [ 0.000000] 00000000 00000000 807bd328 8084bcb1 00000002 00000002 00000001 6d6f4320 [ 0.000000] 00000000 80c97d3d 80c97d68 fffffffc 807bd328 00000000 00000000 00000000 [ 0.000000] 00000000 a0000000 80910000 8110a0b4 00000000 00000020 80010000 80010000 [ 0.000000] ... [ 0.000000] Call Trace: [ 0.000000] [<80008260>] show_stack+0x28/0xf0 [ 0.000000] [<8070c958>] dump_stack_lvl+0x60/0x80 [ 0.000000] [<8002e184>] __warn+0xc4/0xf8 [ 0.000000] [<8002e210>] warn_slowpath_fmt+0x58/0xa4 [ 0.000000] [<801c0fac>] kmem_cache_alloc+0x5a4/0x5e8 [ 0.000000] [<8092856c>] prom_soc_init+0x1fc/0x2b4 [ 0.000000] [<80928060>] prom_init+0x44/0xf0 [ 0.000000] [<80929214>] setup_arch+0x4c/0x6a8 [ 0.000000] [<809257e0>] start_kernel+0x88/0x7c0 [ 0.000000] [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] SoC Type: MediaTek MT7621 ver:1 eco:3 [ 0.000000] printk: bootconsole [early0] enabled This early kzalloc was introduced in commit 71b9b5e0130d ("MIPS: ralink: mt7621: introduce 'soc_device' initialization") Link: https://lore.kernel.org/linux-mm/becf2ac3-2a90-4f3a-96d9-a70f67c66e4a@app.fastmail.com/ Signed-off-by: John Thomson Tested-by: Sergio Paracuellos Acked-by: Sergio Paracuellos --- arch/mips/ralink/mt7621.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/mips/ralink/mt7621.c b/arch/mips/ralink/mt7621.c index f2443b833bc3..836965021d5c 100644 --- a/arch/mips/ralink/mt7621.c +++ b/arch/mips/ralink/mt7621.c @@ -25,6 +25,7 @@ #define MT7621_MEM_TEST_PATTERN 0xaa5555aa static u32 detect_magic __initdata; +struct ralink_soc_info *soc_info_ptr; int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) { @@ -147,27 +148,30 @@ static const char __init *mt7621_get_soc_revision(void) return "E1"; } -static void soc_dev_init(struct ralink_soc_info *soc_info) +static int __init mt7621_soc_dev_init(void) { struct soc_device *soc_dev; struct soc_device_attribute *soc_dev_attr; soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); if (!soc_dev_attr) - return; + return -ENOMEM; soc_dev_attr->soc_id = "mt7621"; soc_dev_attr->family = "Ralink"; soc_dev_attr->revision = mt7621_get_soc_revision(); - soc_dev_attr->data = soc_info; + soc_dev_attr->data = soc_info_ptr; soc_dev = soc_device_register(soc_dev_attr); if (IS_ERR(soc_dev)) { kfree(soc_dev_attr); - return; + return PTR_ERR(soc_dev); } + + return 0; } +device_initcall(mt7621_soc_dev_init); void __init prom_soc_init(struct ralink_soc_info *soc_info) { @@ -209,7 +213,7 @@ void __init prom_soc_init(struct ralink_soc_info *soc_info) soc_info->mem_detect = mt7621_memory_detect; - soc_dev_init(soc_info); + soc_info_ptr = soc_info; if (!register_cps_smp_ops()) return;