From patchwork Sun May 24 16:53:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 1296921 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=sparclinux-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=lgVmuHWz; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49VRC24Mflz9sSF for ; Mon, 25 May 2020 02:54:06 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728847AbgEXQyG (ORCPT ); Sun, 24 May 2020 12:54:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:34050 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728375AbgEXQyF (ORCPT ); Sun, 24 May 2020 12:54:05 -0400 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5264B2073B; Sun, 24 May 2020 16:54:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590339245; bh=tbfyF8Gc0VJZg/qt06s+XuPIZbuK7GsvX8u3HOrwBQY=; h=From:To:Cc:Subject:Date:From; b=lgVmuHWzTKcfFO926HF7v+JvUBv/SAafc4WDxcrRf1btKKf9XdaKY99pxOWRYvR3o cScRHiUgRP1zyTfdcx5N0AS1O53w6n/k9rY4271Bk2ptxtvsMFCW0A6E9BlPTGqL4Y 2TEXdt6SqEojy7Nvm6HJ9m+wBUQ2ofw1Cdz0N1j4= From: Mike Rapoport To: Andrew Morton Cc: "David S. Miller" , Guenter Roeck , sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Mike Rapoport , Mike Rapoport Subject: [PATCH] sparc32: register memory occupied by kernel as memblock.memory Date: Sun, 24 May 2020 19:53:58 +0300 Message-Id: <20200524165358.27188-1-rppt@kernel.org> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Sender: sparclinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: sparclinux@vger.kernel.org From: Mike Rapoport sparc32 never registered the memory occupied by the kernel image with memblock_add() and it only reserved this memory with meblock_reserve(). With openbios as system firmware, the memory occupied by the kernel is reserved in openbios and removed from mem.available. The prom setup code in the kernel uses mem.available to set up the memory banks and essentially there is a hole for the memory occupied by the kernel image. Later in bootmem_init() this memory is memblock_reserve()d. Up until recently, memmap initialization would call __init_single_page() for the pages in that hole, the free_low_memory_core_early() would mark them as reserved and everything would be Ok. After the change in memmap initialization introduced by the commit "mm: memmap_init: iterate over memblock regions rather that check each PFN", the hole is skipped and the page structs for it are not initialized. And when they are passed from memblock to page allocator as reserved, the latter gets confused. Simply registering the memory occupied by the kernel with memblock_add() resolves this issue. Tested on qemu-system-sparc with Debian Etch [1] userspace. [1] https://people.debian.org/~aurel32/qemu/sparc/debian_etch_sparc_small.qcow2 Signed-off-by: Mike Rapoport Link: https://lkml.kernel.org/r/20200517000050.GA87467@roeck-us.nlllllet/ Acked-by: David S. Miller --- David, I'd really appreciate your Ack or an explanation where my analysis is wrong :) arch/sparc/mm/init_32.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c index e45160839f79..eb2946b1df8a 100644 --- a/arch/sparc/mm/init_32.c +++ b/arch/sparc/mm/init_32.c @@ -192,6 +192,7 @@ unsigned long __init bootmem_init(unsigned long *pages_avail) /* Reserve the kernel text/data/bss. */ size = (start_pfn << PAGE_SHIFT) - phys_base; memblock_reserve(phys_base, size); + memblock_add(phys_base, size); size = memblock_phys_mem_size() - memblock_reserved_size(); *pages_avail = (size >> PAGE_SHIFT) - high_pages;