diff options
| author |   H. Peter Anvin <hpa@linux.intel.com> | 2010-08-25 16:38:20 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2010-08-25 17:10:49 -0700 |
| commit | 9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380 (patch) | |
| tree | 8fc6396e340bdc9fb38c90569dafa1abb34080d4 /arch/x86/kernel/setup.c | |
| parent | x86, bios: By default, reserve the low 64K for all BIOSes (diff) | |
| download | linux-dev-9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380.tar.xz linux-dev-9ea77bdb39b62c9bf9fd3cdd1c25a9420bccd380.zip | |
x86, bios: Make the x86 early memory reservation a kernel option
Add a kernel command-line option so the x86 early memory reservation
size can be adjusted at runtime instead of only at compile time.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <tip-d0cd7425fab774a480cce17c2f649984312d0b55@git.kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel/setup.c')
| -rw-r--r-- | arch/x86/kernel/setup.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index eb87f1c83f91..af277e369def 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -618,6 +618,8 @@ static __init void reserve_ibft_region(void) reserve_early_overlap_ok(addr, addr + size, "ibft"); } +static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10; + static void __init trim_bios_range(void) { /* @@ -627,9 +629,9 @@ static void __init trim_bios_range(void) * * This typically reserves additional memory (64KiB by default) * since some BIOSes are known to corrupt low memory. See the - * Kconfig help text for X86_LOW_RESERVE. + * Kconfig help text for X86_RESERVE_LOW. */ - e820_update_range(0, ALIGN(CONFIG_X86_LOW_RESERVE << 10, PAGE_SIZE), + e820_update_range(0, ALIGN(reserve_low, PAGE_SIZE), E820_RAM, E820_RESERVED); /* @@ -641,6 +643,28 @@ static void __init trim_bios_range(void) sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); } +static int __init parse_reservelow(char *p) +{ + unsigned long long size; + + if (!p) + return -EINVAL; + + size = memparse(p, &p); + + if (size < 4096) + size = 4096; + + if (size > 640*1024) + size = 640*1024; + + reserve_low = size; + + return 0; +} + +early_param("reservelow", parse_reservelow); + /* * Determine if we were loaded by an EFI loader. If so, then we have also been * passed the efi memmap, systab, etc., so we should use these data structures |