diff options
| author | Prarit Bhargava <prarit@redhat.com> | 2008-09-24 20:27:49 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-10-08 20:23:01 -0700 |
| commit | 579b4b38460a47b3ba51c35412b960dafe3d0949 (patch) | |
| tree | dc87ce79a86ef76a27ef7dfdb29c61e3c78440de | |
| parent | 130bdec9b321e1c0fdf7c2fdef03166f12815c5a (diff) | |
x86: fix memmap=exactmap boot argument
Backport of d6be118a97ce51ca84035270f91c2bccecbfac5f by Chuck Ebbert
When using kdump modifying the e820 map is yielding strange results.
For example starting with
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000100 - 0000000000093400 (usable)
BIOS-e820: 0000000000093400 - 00000000000a0000 (reserved)
BIOS-e820: 0000000000100000 - 000000003fee0000 (usable)
BIOS-e820: 000000003fee0000 - 000000003fef3000 (ACPI data)
BIOS-e820: 000000003fef3000 - 000000003ff80000 (ACPI NVS)
BIOS-e820: 000000003ff80000 - 0000000040000000 (reserved)
BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
BIOS-e820: 00000000fec00000 - 00000000fec10000 (reserved)
BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
BIOS-e820: 00000000ff000000 - 0000000100000000 (reserved)
and booting with args
memmap=exactmap memmap=640K@0K memmap=5228K@16384K memmap=125188K@22252K memmap=76K#1047424K memmap=564K#1047500K
resulted in:
user-defined physical RAM map:
user: 0000000000000000 - 0000000000093400 (usable)
user: 0000000000093400 - 00000000000a0000 (reserved)
user: 0000000000100000 - 000000003fee0000 (usable)
user: 000000003fee0000 - 000000003fef3000 (ACPI data)
user: 000000003fef3000 - 000000003ff80000 (ACPI NVS)
user: 000000003ff80000 - 0000000040000000 (reserved)
user: 00000000e0000000 - 00000000f0000000 (reserved)
user: 00000000fec00000 - 00000000fec10000 (reserved)
user: 00000000fee00000 - 00000000fee01000 (reserved)
user: 00000000ff000000 - 0000000100000000 (reserved)
But should have resulted in:
user-defined physical RAM map:
user: 0000000000000000 - 00000000000a0000 (usable)
user: 0000000001000000 - 000000000151b000 (usable)
user: 00000000015bb000 - 0000000008ffc000 (usable)
user: 000000003fee0000 - 000000003ff80000 (ACPI data)
This is happening because of an improper usage of strcmp() in the
e820 parsing code. The strcmp() always returns !0 and never resets the
value for e820.nr_map and returns an incorrect user-defined map.
This patch fixes the problem.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | arch/x86/kernel/e820_32.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/e820_64.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/e820_32.c b/arch/x86/kernel/e820_32.c index ed733e7cf4e6..a540c4ee275f 100644 --- a/arch/x86/kernel/e820_32.c +++ b/arch/x86/kernel/e820_32.c @@ -697,7 +697,7 @@ static int __init parse_memmap(char *arg) if (!arg) return -EINVAL; - if (strcmp(arg, "exactmap") == 0) { + if (strncmp(arg, "exactmap", 8) == 0) { #ifdef CONFIG_CRASH_DUMP /* If we are doing a crash dump, we * still need to know the real mem diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c index 124480c0008d..4da8e2bea8b4 100644 --- a/arch/x86/kernel/e820_64.c +++ b/arch/x86/kernel/e820_64.c @@ -776,7 +776,7 @@ static int __init parse_memmap_opt(char *p) char *oldp; unsigned long long start_at, mem_size; - if (!strcmp(p, "exactmap")) { + if (!strncmp(p, "exactmap", 8)) { #ifdef CONFIG_CRASH_DUMP /* * If we are doing a crash dump, we still need to know |