Commit 129182e5 authored Jan 08, 2010 by Andrew Morton Committed by Linus Torvalds Jan 11, 2010

percpu: avoid calling __pcpu_ptr_to_addr(NULL)

__pcpu_ptr_to_addr() can be overridden by the architecture and might not
behave well if passed a NULL pointer.  So avoid calling it until we have
verified that its arg is not NULL.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 8767ba27

mm/percpu.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -1271,7 +1271,7 @@ static void pcpu_reclaim(struct work_struct *work)
		*/
		void free_percpu(void *ptr)
		{
		void *addr = __pcpu_ptr_to_addr(ptr);
		void *addr;
		struct pcpu_chunk *chunk;
		unsigned long flags;
		int off;
		@@ -1279,6 +1279,8 @@ void free_percpu(void *ptr)
		if (!ptr)
		return;

		addr = __pcpu_ptr_to_addr(ptr);

		spin_lock_irqsave(&pcpu_lock, flags);

		chunk = pcpu_chunk_addr_search(addr);

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