Commit 8309cf66 authored Dec 12, 2005 by Eric Dumazet Committed by Linus Torvalds Dec 12, 2005

[PATCH] x86_64: Bug correction in populate_memnodemap()



As reported by Keith Mannthey, there are problems in populate_memnodemap()

The bug was that the compute_hash_shift() was returning 31, with incorrect
initialization of memnodemap[]

To correct the bug, we must use (1UL << shift) instead of (1 << shift) to
avoid an integer overflow, and we must check that shift < 64 to avoid an
infinite loop.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent fd495471

arch/x86_64/mm/numa.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -53,6 +53,8 @@ static int __init populate_memnodemap(
		int res = -1;
		unsigned long addr, end;

		if (shift >= 64)
		return -1;
		memset(memnodemap, 0xff, sizeof(memnodemap));
		for (i = 0; i < numnodes; i++) {
		addr = nodes[i].start;
		@@ -65,7 +67,7 @@ static int __init populate_memnodemap(
		if (memnodemap[addr >> shift] != 0xff)
		return -1;
		memnodemap[addr >> shift] = i;
		addr += (1 << shift);
		addr += (1UL << shift);
		} while (addr < end);
		res = 1;
		}