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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 054FFC433F5 for ; Tue, 19 Oct 2021 05:45:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD8D76138D for ; Tue, 19 Oct 2021 05:45:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233499AbhJSFsK (ORCPT ); Tue, 19 Oct 2021 01:48:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:36502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229527AbhJSFsI (ORCPT ); Tue, 19 Oct 2021 01:48:08 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D89D36108E; Tue, 19 Oct 2021 05:45:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634622356; bh=4tFcqwTRXqGKGRhpNjefcElR0f+rUUFI3ptNbOGbzQ8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WoCIneDVFecJl23oybkx9yUnJvdgy+f+amkOJAvBqJpz2zuSyoCxeqbT7ng87zswj qO9bagM7SZL6TsJfld6lr8ZrjSld5n5OvUIsy1QbL+9fdwqmQD98DFpVw/omy6UbVN jJpBs7vRcIB+OAMTzjITkRGXLzQwCJTl/YxkFW+1kqCGfh7IMiexscmHgoDk0ImT9P eScU6czzxnj+cFS7CSY8Xt9xuAstWDw4a1UxS9Bslrx+wBxE2u91nwaEem7f1LTzDa BnxUdjZYnJWDsx+324qsKQmw8K9QiL4mKU8XmqFAMtb8/TAP9IGLjQkaq1Jhube4qk uuY6NxPizwwVA== Date: Tue, 19 Oct 2021 08:45:49 +0300 From: Mike Rapoport To: Qian Cai Cc: linux-mm@kvack.org, Andrew Morton , Catalin Marinas , Mike Rapoport , Vladimir Zapolskiy , linux-kernel@vger.kernel.org, Linus Torvalds Subject: Re: [PATCH] memblock: exclude NOMAP regions from kmemleak Message-ID: References: <20211013054756.12177-1-rppt@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Qian, On Mon, Oct 18, 2021 at 11:55:40PM -0400, Qian Cai wrote: > > > On 10/13/2021 1:47 AM, Mike Rapoport wrote: > > From: Mike Rapoport > > > > Vladimir Zapolskiy reports: > > > > commit a7259df76702 ("memblock: make memblock_find_in_range method private") > > invokes a kernel panic while running kmemleak on OF platforms with nomaped > > regions: > > > > Unable to handle kernel paging request at virtual address fff000021e00000 > > [...] > > scan_block+0x64/0x170 > > scan_gray_list+0xe8/0x17c > > kmemleak_scan+0x270/0x514 > > kmemleak_write+0x34c/0x4ac > > > > Indeed, NOMAP regions don't have linear map entries so an attempt to scan > > these areas would fault. > > > > Prevent such faults by excluding NOMAP regions from kmemleak. > > > > Link: https://lore.kernel.org/all/8ade5174-b143-d621-8c8e-dc6a1898c6fb@linaro.org > > Fixes: a7259df76702 ("memblock: make memblock_find_in_range method private") > > Signed-off-by: Mike Rapoport > > Tested-by: Vladimir Zapolskiy > > Mike, reverting this commit on the top of today's linux-next fixed the early booting hang > on an arm64 server with kmemleak. Even with "earlycon", it could only print out those > lines. > > EFI stub: Booting Linux Kernel... > EFI stub: EFI_RNG_PROTOCOL unavailable > EFI stub: ERROR: FIRMWARE BUG: kernel image not aligned on 128k boundary > EFI stub: ERROR: FIRMWARE BUG: Image BSS overlaps adjacent EFI memory region > EFI stub: Using DTB from configuration table > EFI stub: Exiting boot services… > > I could help to confirm if it hangs right in the early boot somewhere if needed. The kernel config and a log of working kernel would help to start with. > start_kernel() > setup_arch() > paging_init() > map_mem() > memblock_mark_nomap( So we have kmemleak_free_part_phys() here. Catalin, any ideas? > > > --- > > mm/memblock.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/mm/memblock.c b/mm/memblock.c > > index 184dcd2e5d99..5c3503c98b2f 100644 > > --- a/mm/memblock.c > > +++ b/mm/memblock.c > > @@ -936,7 +936,12 @@ int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size) > > */ > > int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size) > > { > > - return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP); > > + int ret = memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP); > > + > > + if (!ret) > > + kmemleak_free_part_phys(base, size); > > + > > + return ret; > > } > > > > /** > > > > base-commit: 64570fbc14f8d7cb3fe3995f20e26bc25ce4b2cc > > -- Sincerely yours, Mike.