On Wed, Jan 25, 2017 at 5:21 AM, Michal Hocko <mhocko@xxxxxxxxxx> wrote:[...]
On Wed 25-01-17 14:10:06, Michal Hocko wrote:
On Tue 24-01-17 11:17:21, Alexei Starovoitov wrote:
Are there any more comments? I would really appreciate to hear from
networking folks before I resubmit the series.
while this patchset was baking the bpf side switched to use bpf_map_area_alloc()
which fixes the issue with missing __GFP_NORETRY that we had to fix quickly.
See commit d407bd25a204 ("bpf: don't trigger OOM killer under pressure with map alloc")
it covers all kmalloc/vmalloc pairs instead of just one place as in this set.
So please rebase and switch bpf_map_area_alloc() to use kvmalloc().
OK, will do. Thanks for the heads up.
Just for the record, I will fold the following into the patch 1
---
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 19b6129eab23..8697f43cf93c 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -53,21 +53,7 @@ void bpf_register_map_type(struct bpf_map_type_list *tl)
void *bpf_map_area_alloc(size_t size)
{
- /* We definitely need __GFP_NORETRY, so OOM killer doesn't
- * trigger under memory pressure as we really just want to
- * fail instead.
- */
- const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
- void *area;
-
- if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
- area = kmalloc(size, GFP_USER | flags);
- if (area != NULL)
- return area;
- }
-
- return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | flags,
- PAGE_KERNEL);
+ return kvzalloc(size, GFP_USER);
}
void bpf_map_area_free(void *area)
Looks fine by me.
Daniel, thoughts?