Re: [PATCH] mm: avoid uninitialized variable in tracepoint
flat view
From: Kirill A. Shutemov <hidden>
Date: 2016-01-18 23:03:30
Also in:
linux-arm-kernel, linux-mm
On Mon, Jan 18, 2016 at 09:50:26PM +0100, Arnd Bergmann wrote:
A newly added tracepoint in the hugepage code uses a variable in the
error handling that is not initialized at that point:
include/trace/events/huge_memory.h:81:230: error: 'isolated' may be used uninitialized in this function [-Werror=maybe-uninitialized]
The result is relatively harmless, as the trace data will in rare
cases contain incorrect data.
This works around the problem by adding an explicit initialization.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 7d2eba0557c1 ("mm: add tracepoint for scanning pages")There's the same patch in mm tree, but it got lost on the way to Linus' tree: https://ozlabs.org/~akpm/mmots/broken-out/mm-make-optimistic-check-for-swapin-readahead-fix.patch Andrew?
quoted hunk ↗ jump to hunk
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index b2db98136af9..bb3b763b1829 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c@@ -2320,7 +2320,7 @@ static void collapse_huge_page(struct mm_struct *mm, pgtable_t pgtable; struct page *new_page; spinlock_t *pmd_ptl, *pte_ptl; - int isolated, result = 0; + int isolated = 0, result = 0; unsigned long hstart, hend; struct mem_cgroup *memcg; unsigned long mmun_start; /* For mmu_notifiers */
-- Kirill A. Shutemov