From eed63519e3e74d515d2007ecd895338d0ba2a85c Mon Sep 17 00:00:00 2001
From: Ian Campbell <ian.campbell@citrix.com>
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 <ian.campbell@citrix.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Joel Becker <joel.becker@oracle.com>
Tested-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Miller <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1269830604-26214-4-git-send-email-yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
kernel/early_res.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/kernel/early_res.c b/kernel/early_res.c
index 3cb2c661bb78..31aa9332ef3f 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)
--
GitLab