Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758455Ab0DHG7v (ORCPT ); Thu, 8 Apr 2010 02:59:51 -0400 Received: from acsinet12.oracle.com ([141.146.126.234]:62808 "EHLO acsinet12.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758436Ab0DHG7t (ORCPT ); Thu, 8 Apr 2010 02:59:49 -0400 Message-ID: <4BBD7E52.80507@oracle.com> Date: Wed, 07 Apr 2010 23:57:22 -0700 From: Yinghai User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100228 SUSE/3.0.3-1.1.1 Thunderbird/3.0.3 MIME-Version: 1.0 To: Liang Li , Jeremy Fitzhardinge , Rusty Russell CC: Yinghai , 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 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> <20100408045945.GB26543@localhost> In-Reply-To: <20100408045945.GB26543@localhost> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: acsmt353.oracle.com [141.146.40.153] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090206.4BBD7EB7.00CA:SCFMA4539814,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5441 Lines: 154 On 04/07/2010 09:59 PM, Liang Li wrote: > 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? > good to me. may need to ask xen/lguest/vmi related to check that too. arch/x86/kernel/vmi_32.c: reserve_top_address(-vmi_rom->virtual_top); arch/x86/lguest/boot.c: reserve_top_address(lguest_data.reserve_mem); arch/x86/mm/pgtable_32.c: reserve_top_address(address); arch/x86/xen/mmu.c: reserve_top_address(-top); YH -- 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/