On 32-bit systems, we'll lose the top bits of index because arithmetic will be performed in unsigned long instead of unsigned long long. This affects files over 4GB in size.
Fixes: 6100e34b2526 ("mm, memory_failure: Teach memory_failure() about dev_pagemap pages") Cc: stable@vger.kernel.org Signed-off-by: Matthew Wilcox (Oracle) willy@infradead.org --- mm/memory-failure.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 82e15baabb48..455093f73a70 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1704,7 +1704,7 @@ static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn, * mapping being torn down is communicated in siginfo, see * kill_proc() */ - loff_t start = (index << PAGE_SHIFT) & ~(size - 1); + loff_t start = ((loff_t)index << PAGE_SHIFT) & ~(size - 1);
unmap_mapping_range(mapping, start, size, 0); }