Re: percpu allocation failures

From: Luis Henriques
Date: Wed Sep 27 2017 - 05:05:52 EST

Dennis Zhou <dennisszhou@xxxxxxxxx> writes:

> Hi Luis,
> This seems to be an issue with the reserved chunk being unable to
> allocate memory when loading kernel modules. Unfortunately, I have not
> been successful in reproducing this with the reserved chunk allocation
> path exposed or by inserting the nft_meta module.
> Could you please send me the output when ran with the following patch
> and the output of the percpu memory statistics file before and after
> inserting the module (PERCPU_STATS)? The stats are in
> /sys/kernel/debug/percpu_stats.

Please find attached all the info you requested. Hope it helps.

Also, here's the nft script I'm using to trigger the issue locally:

#!/usr/sbin/nft -f

flush ruleset

table inet filter {
chain input {
type filter hook input priority 0;
iif lo accept
ct state established,related accept
tcp dport { 22 } ct state new accept
ip6 nexthdr icmpv6 icmpv6 type { nd-neighbor-solicit, nd-router-advert, nd-neighbor-advert } accept
counter drop


Attachment: percpu_stats.before
Description: Binary data

Attachment: percpu_stats.after
Description: Binary data

Attachment: dmesg.debug
Description: Binary data