lkml.org 
[lkml]   [2009]   [Aug]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subjectlinux-next: reservetop fix disables mem=
I find the "mem=" boot parameter disabled in today's linux-next:
reverting the tip commit below fixes that.

Hugh

From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Date: Thu, 20 Aug 2009 12:23:11 +0000 (+0800)
Subject: x86: Fix system crash when loading with "reservetop" parameter
X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Fmingo%2Flinux-2.6-x86.git;a=commitdiff_plain;h=8126dec32738421afa362114337331337b4be17f

x86: Fix system crash when loading with "reservetop" parameter

The system will die if the kernel is booted with "reservetop"
parameter, in present code, parse "reservetop" parameter after
early_ioremap_init(), and some function still use
early_ioremap() after it.

The problem is, "reservetop" parameter can modify
'FIXADDR_TOP', then the virtual address got by early_ioremap()
is base on old 'FIXADDR_TOP', but the page mapping is base on
new 'FIXADDR_TOP', it will occur page fault, and the IDT is not
prepare yet, so, the system is dead.

So, put parse_early_param() in the front of
early_ioremap_init() in this patch.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: yinghai@kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A8D402F.4080805@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 63f32d2..02643cc 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -711,6 +711,11 @@ void __init setup_arch(char **cmdline_p)
printk(KERN_INFO "Command line: %s\n", boot_command_line);
#endif

+ strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
+ *cmdline_p = command_line;
+
+ parse_early_param();
+
/* VMI may relocate the fixmap; do this before touching ioremap area */
vmi_init();

@@ -793,11 +798,6 @@ void __init setup_arch(char **cmdline_p)
#endif
#endif

- strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
- *cmdline_p = command_line;
-
- parse_early_param();
-
#ifdef CONFIG_X86_64
check_efer();
#endif

\
 
 \ /
  Last update: 2009-08-24 18:49    [W:0.112 / U:0.212 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site