On 7/15/19 6:06 AM, Matthew Wilcox wrote:
On Sun, Jul 14, 2019 at 08:47:07PM -0700, Yang Shi wrote:
On 7/13/19 2:25 PM, Matthew Wilcox wrote:
On Sat, Jul 13, 2019 at 04:49:04AM +0800, Yang Shi wrote:
When running ltp's oom test with kmemleak enabled, the below warning was
triggerred since kernel detects __GFP_NOFAIL & ~__GFP_DIRECT_RECLAIM is
passed in:
There are lots of places where kmemleak will call kmalloc with
__GFP_NOFAIL and ~__GFP_DIRECT_RECLAIM (including the XArray code, which
is how I know about it). It needs to be fixed to allow its internal
allocations to fail and return failure of the original allocation as
a consequence.
Do you mean kmemleak internal allocation? It would fail even though
__GFP_NOFAIL is passed in if GFP_NOWAIT is specified. Currently buddy
allocator will not retry if the allocation is non-blockable.
Actually it sets off a warning. Which is the right response from the
core mm code because specifying __GFP_NOFAIL and __GFP_NOWAIT makes no
sense.
Yes, this is what I meant. Kmemleak did a trick to fool fault-injection
by passing in __GFP_NOFAIL, but it doesn't make sense for non-blockable
allocation.
