Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753488Ab0DHFBn (ORCPT ); Thu, 8 Apr 2010 01:01:43 -0400 Received: from mail.windriver.com ([147.11.1.11]:45519 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751715Ab0DHFBm (ORCPT ); Thu, 8 Apr 2010 01:01:42 -0400 Date: Thu, 8 Apr 2010 12:59:45 +0800 From: Liang Li To: Yinghai Cc: akpm@linux-foundation.org, hpa@zytor.com, mingo@elte.hu, tglx@linutronix.de, wangchen@cn.fujitsu.com, "linux-kernel@vger.kernel.org" Subject: Re: + x86-fix-handling-of-the-reservetop-boot-option.patch added to -mm tree Message-ID: <20100408045945.GB26543@localhost> Reply-To: Liang Li References: <201004072200.o37M0d19009878@imap1.linux-foundation.org> <4BBD1AA3.4000204@oracle.com> <20100408010558.GA4053@localhost> <4BBD2DD4.1060101@oracle.com> <20100408015353.GB4053@localhost> <4BBD5BEF.3000406@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4BBD5BEF.3000406@oracle.com> User-Agent: Mutt/1.5.20 (2009-08-17) X-OriginalArrivalTime: 08 Apr 2010 05:01:01.0071 (UTC) FILETIME=[7BBC79F0:01CAD6D8] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4906 Lines: 144 On Wed, Apr 07, 2010 at 09:30:39PM -0700, Yinghai wrote: > On 04/07/2010 06:53 PM, Liang Li wrote: > > Does this similar modification like this is more preferred? > > > > diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h > > index a1dcfa3..30a3e97 100644 > > --- a/arch/x86/include/asm/io.h > > +++ b/arch/x86/include/asm/io.h > > @@ -347,6 +347,7 @@ extern void __iomem *early_ioremap(resource_size_t phys_addr, > > extern void __iomem *early_memremap(resource_size_t phys_addr, > > unsigned long size); > > extern void early_iounmap(void __iomem *addr, unsigned long size); > > +extern void fixup_early_ioremap(void); > > > > #define IO_SPACE_LIMIT 0xffff > > > > diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c > > index ea82ef0..fe06296 100644 > > --- a/arch/x86/mm/ioremap.c > > +++ b/arch/x86/mm/ioremap.c > > @@ -448,6 +448,23 @@ static inline void __init early_clear_fixmap(enum fixed_addresses idx) > > static void __iomem *prev_map[FIX_BTMAPS_SLOTS] __initdata; > > static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata; > > > > +void __init fixup_early_ioremap(void) > > +{ > > + int i; > > + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) { > > + if (prev_map[i]) > > + break; > > + } > > + > > + if (i == FIX_BTMAPS_SLOTS) > < > > + WARN_ON(1); > BUG_ON() > > + > > + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) > > + slot_virt[i] = __fix_to_virt(FIX_BTMAP_BEGIN - NR_FIX_BTMAPS * i); > > + > need to clear the old PMD, and set new PMD. > > so you can clear old PMD and call early_ioremap_init() in fixup_early_ioremap() Call early_ioremap_init will do the update PMD work. So the preferred patch would be: --------------- >From 61fe7a116cbbf6eef98a49b88ed5861ed9ebd32d Mon Sep 17 00:00:00 2001 From: Liang Li Date: Mon, 22 Mar 2010 18:38:14 +0800 Subject: [PATCH] x86: let 'reservetop' functioning right When specify 'reservetop=0xbadc0de' kernel parameter, the kernel will stop booting due to a early_ioremap bug that relate to commit 8827247ff. The root cause of boot failure problem is the value of 'slot_virt[i]' was initialized in setup_arch->early_ioremap_init. But later in setup_arch, the function 'parse_early_param' will modify 'FIXADDR_TOP' when 'reservetop=0xbadc0de' being specified. When reservetop being handled then FIXADDR_TOP get adjusted, Hence check prev_map then re-initialize slot_virt and PMD based on new FIXADDR_TOP. Signed-off-by: Liang Li Cc: Wang Chen Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Yinghai Lu Cc: Andrew Morton --- arch/x86/include/asm/io.h | 1 + arch/x86/mm/ioremap.c | 15 +++++++++++++++ arch/x86/mm/pgtable.c | 2 ++ 3 files changed, 18 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index a1dcfa3..30a3e97 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -347,6 +347,7 @@ extern void __iomem *early_ioremap(resource_size_t phys_addr, extern void __iomem *early_memremap(resource_size_t phys_addr, unsigned long size); extern void early_iounmap(void __iomem *addr, unsigned long size); +extern void fixup_early_ioremap(void); #define IO_SPACE_LIMIT 0xffff diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 5eb1ba7..e4ab706 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -448,6 +448,21 @@ static inline void __init early_clear_fixmap(enum fixed_addresses idx) static void __iomem *prev_map[FIX_BTMAPS_SLOTS] __initdata; static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata; +void __init fixup_early_ioremap(void) +{ + int i; + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) { + if (prev_map[i]) + break; + } + + if (i < FIX_BTMAPS_SLOTS) + BUG_ON(1); + + early_ioremap_init(); + return; +} + static int __init check_early_ioremap_leak(void) { int count = 0; diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 5c4ee42..ea4d54c 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -4,6 +4,7 @@ #include #include #include +#include #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO @@ -351,6 +352,7 @@ void __init reserve_top_address(unsigned long reserve) printk(KERN_INFO "Reserving virtual address space above 0x%08x\n", (int)-reserve); __FIXADDR_TOP = -reserve - PAGE_SIZE; + fixup_early_ioremap(); #endif } ----------- Acceptable? Thanks and regards, -Liang Li -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/