iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

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

Browse Source 
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>
This commit is contained in:
Xiao Guangrong 2009-08-20 20:23:11 +08:00 committed by Ingo Molnar
parent fc0ce23506
commit 8126dec327
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/kernel/setup.c
View File

@ -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