From 5dca6a1bb014875a17289fdaae8c31e0a3641c99 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Tue, 18 Mar 2008 16:44:19 -0700 Subject: x86: trim mtrr don't close gap for resource allocation. fix the bug reported here: http://bugzilla.kernel.org/show_bug.cgi?id=10232 use update_memory_range() instead of add_memory_range() directly to avoid closing the gap. ( the new code only affects and runs on systems where the MTRR workaround triggers. ) Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/e820_64.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'arch/x86/kernel/e820_64.c') diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c index 9f65b4cc323c..9be697126013 100644 --- a/arch/x86/kernel/e820_64.c +++ b/arch/x86/kernel/e820_64.c @@ -744,6 +744,33 @@ void __init finish_e820_parsing(void) } } +void __init update_memory_range(u64 start, u64 size, unsigned old_type, + unsigned new_type) +{ + int i; + + BUG_ON(old_type == new_type); + + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + u64 final_start, final_end; + if (ei->type != old_type) + continue; + /* totally covered? */ + if (ei->addr >= start && ei->size <= size) { + ei->type = new_type; + continue; + } + /* partially covered */ + final_start = max(start, ei->addr); + final_end = min(start + size, ei->addr + ei->size); + if (final_start >= final_end) + continue; + add_memory_region(final_start, final_end - final_start, + new_type); + } +} + void __init update_e820(void) { u8 nr_map; -- cgit v1.2.3