From: Namhyung Kim <namhyung@xxxxxxxxxx> Since we're finding a cause of broken data, it'd be desired not to miss any suspects. It doesn't use GFP_ATOMIC since it includes __GFP_HIGH which is for system making forward progress. It also adds a WARN_ON whenever it fails to allocate pages even with __GFP_ATOMIC. Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> --- mm/kasan/vchecker.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/kasan/vchecker.c b/mm/kasan/vchecker.c index 6b3824f..df480d5 100644 --- a/mm/kasan/vchecker.c +++ b/mm/kasan/vchecker.c @@ -301,13 +301,20 @@ static noinline depot_stack_handle_t save_stack(int skip, bool *is_new) .max_entries = VCHECKER_STACK_DEPTH, .skip = skip, }; + depot_stack_handle_t handle; save_stack_trace(&trace); if (trace.nr_entries != 0 && trace.entries[trace.nr_entries-1] == ULONG_MAX) trace.nr_entries--; - return depot_save_stack(NULL, &trace, GFP_NOWAIT, is_new); + if (trace.nr_entries == 0) + return 0; + + handle = depot_save_stack(NULL, &trace, __GFP_ATOMIC, is_new); + WARN_ON(!handle); + + return handle; } static ssize_t vchecker_type_write(struct file *filp, const char __user *ubuf, -- 2.7.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
