On 07/26/2018 09:26 AM, Michal Hocko wrote: > On Thu 26-07-18 09:18:57, Vlastimil Babka wrote: >> On 07/25/2018 09:52 PM, Andrew Morton wrote: >>> (switched to email. Please respond via emailed reply-to-all, not via the >>> bugzilla web interface). >>> >>> On Wed, 25 Jul 2018 11:42:57 +0000 bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: >>> >>>> https://bugzilla.kernel.org/show_bug.cgi?id=200651 >>>> >>>> Bug ID: 200651 >>>> Summary: cgroups iptables-restor: vmalloc: allocation failure >>> >>> Thanks. Please do note the above request. >>> >>>> Product: Memory Management >>>> Version: 2.5 >>>> Kernel Version: 4.14 >>>> Hardware: All >>>> OS: Linux >>>> Tree: Mainline >>>> Status: NEW >>>> Severity: normal >>>> Priority: P1 >>>> Component: Other >>>> Assignee: akpm@xxxxxxxxxxxxxxxxxxxx >>>> Reporter: gnikolov@xxxxxxxxxxx >>>> Regression: No >>>> >>>> Created attachment 277505 >>>> --> https://bugzilla.kernel.org/attachment.cgi?id=277505&action=edit >>>> iptables save >>>> >>>> After creating large number of cgroups and under memory pressure, iptables >>>> command fails with following error: >>>> >>>> "iptables-restor: vmalloc: allocation failure, allocated 3047424 of 3465216 >>>> bytes, mode:0x14010c0(GFP_KERNEL|__GFP_NORETRY), nodemask=(null)" >> >> This is likely the kvmalloc() in xt_alloc_table_info(). Between 4.13 and >> 4.17 it shouldn't use __GFP_NORETRY, but looks like commit 0537250fdc6c >> ("netfilter: x_tables: make allocation less aggressive") was backported >> to 4.14. Removing __GFP_NORETRY might help here, but bring back other >> issues. Less than 4MB is not that much though, maybe find some "sane" >> limit and use __GFP_NORETRY only above that? > > I have seen the same report via http://lkml.kernel.org/r/df6f501c-8546-1f55-40b1-7e3a8f54d872@xxxxxxxxxxx > and the reported confirmed that kvmalloc is not a real culprit > http://lkml.kernel.org/r/d99a9598-808a-6968-4131-c3949b752004@xxxxxxxxxxx Hmm but that was revert of eacd86ca3b03 ("net/netfilter/x_tables.c: use kvmalloc() in xt_alloc_table_info()") which was the 4.13 commit that removed __GFP_NORETRY (there's no __GFP_NORETRY under net/netfilter in v4.14). I assume it was reverted on top of vanilla v4.14 as there would be conflict on the stable with 0537250fdc6c backport. So what should be tested to be sure is either vanilla v4.14 without stable backports, or latest v4.14.y with revert of 0537250fdc6c.
