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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8980DC432BE for ; Tue, 31 Aug 2021 17:40:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7061260FE8 for ; Tue, 31 Aug 2021 17:40:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240482AbhHaRlu (ORCPT ); Tue, 31 Aug 2021 13:41:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:38842 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233619AbhHaRlt (ORCPT ); Tue, 31 Aug 2021 13:41:49 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 512AE60C3E; Tue, 31 Aug 2021 17:40:51 +0000 (UTC) Date: Tue, 31 Aug 2021 18:40:48 +0100 From: Catalin Marinas To: Chen Wandun Cc: will@kernel.org, ardb@kernel.org, rppt@kernel.org, akpm@linux-foundation.org, nsaenz@kernel.org, anshuman.khandual@arm.com, geert+renesas@glider.be, rafael.j.wysocki@intel.com, robh@kernel.org, kirill.shtuemov@linux.intel.com, sfr@canb.auug.org.au, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, wangkefeng.wang@huawei.com, weiyongjun1@huawei.com, guohanjun@huawei.com Subject: Re: [PATCH] arm64: kdump: Skip kmemleak scan reserved memory for kdump Message-ID: References: <20210827092246.3565437-1-chenwandun@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210827092246.3565437-1-chenwandun@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 27, 2021 at 05:22:46PM +0800, Chen Wandun wrote: > Trying to boot with kdump + kmemleak, command will result in a crash: > "echo scan > /sys/kernel/debug/kmemleak" > > crashkernel reserved: 0x0000000007c00000 - 0x0000000027c00000 (512 MB) > Kernel command line: BOOT_IMAGE=(hd1,gpt2)/vmlinuz-5.14.0-rc5-next-20210809+ root=/dev/mapper/ao-root ro rd.lvm.lv=ao/root rd.lvm.lv=ao/swap crashkernel=512M > Unable to handle kernel paging request at virtual address ffff000007c00000 > Mem abort info: > ESR = 0x96000007 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x07: level 3 translation fault > Data abort info: > ISV = 0, ISS = 0x00000007 > CM = 0, WnR = 0 > swapper pgtable: 64k pages, 48-bit VAs, pgdp=00002024f0d80000 > [ffff000007c00000] pgd=1800205ffffd0003, p4d=1800205ffffd0003, pud=1800205ffffd0003, pmd=1800205ffffc0003, pte=0068000007c00f06 > Internal error: Oops: 96000007 [#1] SMP > pstate: 804000c9 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : scan_block+0x98/0x230 > lr : scan_block+0x94/0x230 > sp : ffff80008d6cfb70 > x29: ffff80008d6cfb70 x28: 0000000000000000 x27: 0000000000000000 > x26: 00000000000000c0 x25: 0000000000000001 x24: 0000000000000000 > x23: ffffa88a6b18b398 x22: ffff000007c00ff9 x21: ffffa88a6ac7fc40 > x20: ffffa88a6af6a830 x19: ffff000007c00000 x18: 0000000000000000 > x17: 0000000000000000 x16: 0000000000000000 x15: ffffffffffffffff > x14: ffffffff00000000 x13: ffffffffffffffff x12: 0000000000000020 > x11: 0000000000000000 x10: 0000000001080000 x9 : ffffa88a6951c77c > x8 : ffffa88a6a893988 x7 : ffff203ff6cfb3c0 x6 : ffffa88a6a52b3c0 > x5 : ffff203ff6cfb3c0 x4 : 0000000000000000 x3 : 0000000000000000 > x2 : 0000000000000001 x1 : ffff20226cb56a40 x0 : 0000000000000000 > Call trace: > scan_block+0x98/0x230 > scan_gray_list+0x120/0x270 > kmemleak_scan+0x3a0/0x648 > kmemleak_write+0x3ac/0x4c8 > full_proxy_write+0x6c/0xa0 > vfs_write+0xc8/0x2b8 > ksys_write+0x70/0xf8 > __arm64_sys_write+0x24/0x30 > invoke_syscall+0x4c/0x110 > el0_svc_common+0x9c/0x190 > do_el0_svc+0x30/0x98 > el0_svc+0x28/0xd8 > el0t_64_sync_handler+0x90/0xb8 > el0t_64_sync+0x180/0x184 > > The reserved memory for kdump will be looked up by kmemleak, this area > will be set invalid when kdump service is bring up. That will result in > crash when kmemleak scan this area. > > Fixes: 461ef12c4375 ("memblock: make memblock_find_in_range method private") > Signed-off-by: Chen Wandun > --- > arch/arm64/mm/init.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index b16be52233c6..dc0c44622bfd 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -30,6 +30,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -101,6 +102,7 @@ static void __init reserve_crashkernel(void) > pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", > crash_base, crash_base + crash_size, crash_size >> 20); > > + kmemleak_ignore_phys(crash_base); > crashk_res.start = crash_base; > crashk_res.end = crash_base + crash_size - 1; > } I'd add a comment here along the lines of (feel free to change it): /* * The crashkernel memory will be removed from the kernel linear * map. Inform kmemleak so that it won't try to access it. */ With that: Reviewed-by: Catalin Marinas