diff options
| author | Yinghai Lu <yinghai@kernel.org> | 2009-02-22 22:14:56 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-02-23 07:41:31 +0100 |
| commit | ecda06289f8202d4c6beb235f59ea464f4a91209 (patch) | |
| tree | 351d1919e4ea31dc727b6793bab2527461d06ef5 | |
| parent | 8e6dafd6c741cd4679b4de3c5d9698851e4fa59c (diff) | |
x86: check mptable physptr with max_low_pfn on 32bit
Impact: fix early crash on LinuxBIOS systems
Kevin O'Connor reported that Coreboot aka LinuxBIOS tries to put
mptable somewhere very high, well above max_low_pfn (below which
BIOSes generally put the mptable), causing a panic.
The BIOS will probably be changed to be compatible with older
Linus versions, but nevertheless the MP-spec does not forbid
an MP-table in arbitrary system RAM, so make sure it all
works even if the table is in an unexpected place.
Check physptr with max_low_pfn * PAGE_SIZE.
Reported-by: Kevin O'Connor <kevin@koconnor.net>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Stefan Reinauer <stepan@coresystems.de>
Cc: coreboot@coreboot.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/mpparse.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c index 7f4d2586972..37cb1bda1ba 100644 --- a/arch/x86/kernel/mpparse.c +++ b/arch/x86/kernel/mpparse.c @@ -710,13 +710,22 @@ static int __init smp_scan_config(unsigned long base, unsigned long length, * of physical memory; so that simply reserving * PAGE_SIZE from mpf->physptr yields BUG() * in reserve_bootmem. + * also need to make sure physptr is below than + * max_low_pfn + * we don't need reserve the area above max_low_pfn */ unsigned long end = max_low_pfn * PAGE_SIZE; - if (mpf->physptr + size > end) - size = end - mpf->physptr; -#endif + + if (mpf->physptr < end) { + if (mpf->physptr + size > end) + size = end - mpf->physptr; + reserve_bootmem_generic(mpf->physptr, size, + BOOTMEM_DEFAULT); + } +#else reserve_bootmem_generic(mpf->physptr, size, BOOTMEM_DEFAULT); +#endif } return 1; |