From eed63519e3e74d515d2007ecd895338d0ba2a85c Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Sun, 28 Mar 2010 19:42:56 -0700 Subject: [PATCH] x86: Do not free zero sized per cpu areas This avoids an infinite loop in free_early_partial(). Add a warning to free_early_partial() to catch future problems. -v5: put back start > end back into WARN_ONCE() -v6: use one line for warning, suggested by Linus -v7: more tests -v8: remove the function name as suggested by Johannes WARN_ONCE() will print out that function name. Signed-off-by: Ian Campbell Signed-off-by: Yinghai Lu Tested-by: Konrad Rzeszutek Wilk Tested-by: Joel Becker Tested-by: Stanislaw Gruszka Acked-by: Johannes Weiner Cc: Peter Zijlstra Cc: David Miller Cc: Benjamin Herrenschmidt Cc: Linus Torvalds LKML-Reference: <1269830604-26214-4-git-send-email-yinghai@kernel.org> Signed-off-by: Ingo Molnar --- kernel/early_res.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/early_res.c b/kernel/early_res.c index 3cb2c661bb781..31aa9332ef3f8 100644 --- a/kernel/early_res.c +++ b/kernel/early_res.c @@ -333,6 +333,12 @@ void __init free_early_partial(u64 start, u64 end) struct early_res *r; int i; + if (start == end) + return; + + if (WARN_ONCE(start > end, " wrong range [%#llx, %#llx]\n", start, end)) + return; + try_next: i = find_overlapped_early(start, end); if (i >= max_early_res)