lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 12 Jun 2020 15:13:22 +0530 From: Naresh Kamboju <naresh.kamboju@...aro.org> To: Michal Hocko <mhocko@...nel.org> Cc: Chris Down <chris@...isdown.name>, Yafang Shao <laoar.shao@...il.com>, Anders Roxell <anders.roxell@...aro.org>, "Linux F2FS DEV, Mailing List" <linux-f2fs-devel@...ts.sourceforge.net>, linux-ext4 <linux-ext4@...r.kernel.org>, linux-block <linux-block@...r.kernel.org>, Andrew Morton <akpm@...ux-foundation.org>, open list <linux-kernel@...r.kernel.org>, Linux-Next Mailing List <linux-next@...r.kernel.org>, linux-mm <linux-mm@...ck.org>, Arnd Bergmann <arnd@...db.de>, Andreas Dilger <adilger.kernel@...ger.ca>, Jaegeuk Kim <jaegeuk@...nel.org>, "Theodore Ts'o" <tytso@....edu>, Chao Yu <chao@...nel.org>, Hugh Dickins <hughd@...gle.com>, Andrea Arcangeli <aarcange@...hat.com>, Matthew Wilcox <willy@...radead.org>, Chao Yu <yuchao0@...wei.com>, lkft-triage@...ts.linaro.org, Johannes Weiner <hannes@...xchg.org>, Roman Gushchin <guro@...com>, Cgroups <cgroups@...r.kernel.org> Subject: Re: mm: mkfs.ext4 invoked oom-killer on i386 - pagecache_get_page On Thu, 11 Jun 2020 at 15:25, Michal Hocko <mhocko@...nel.org> wrote: > > On Fri 29-05-20 11:49:20, Michal Hocko wrote: > > On Fri 29-05-20 02:56:44, Chris Down wrote: > > > Yafang Shao writes: > > Agreed. Even if e{low,min} might still have some rough edges I am > > completely puzzled how we could end up oom if none of the protection > > path triggers which the additional debugging should confirm. Maybe my > > debugging patch is incomplete or used incorrectly (maybe it would be > > esier to use printk rather than trace_printk?). > > It would be really great if we could move forward. While the fix (which > has been dropped from mmotm) is not super urgent I would really like to > understand how it could hit the observed behavior. Can we double check > that the debugging patch really doesn't trigger (e.g. > s@...ce_printk@...ntk in the first step)? Please suggest to me the way to get more debug information by providing kernel debug patches and extra kernel configs. I have applied your debug patch and tested on top on linux next 20200612 but did not find any printk output while running mkfs -t ext4 /drive test case. > I have checked it again but > do not see any potential code path which would be affected by the patch > yet not trigger any output. But another pair of eyes would be really > great. --- diff --git a/mm/vmscan.c b/mm/vmscan.c index b6d84326bdf2..d13ce7b02de4 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2375,6 +2375,8 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, * sc->priority further than desirable. */ scan = max(scan, SWAP_CLUSTER_MAX); + + trace_printk("scan:%lu protection:%lu\n", scan, protection); } else { scan = lruvec_size; } @@ -2618,6 +2620,7 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc) switch (mem_cgroup_protected(target_memcg, memcg)) { case MEMCG_PROT_MIN: + trace_printk("under min:%lu emin:%lu\n", memcg->memory.min, memcg->memory.emin); /* * Hard protection. * If there is no reclaimable memory, OOM. @@ -2630,6 +2633,7 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc) * there is an unprotected supply * of reclaimable memory from other cgroups. */ + trace_printk("under low:%lu elow:%lu\n", memcg->memory.low, memcg->memory.elow); if (!sc->memcg_low_reclaim) { sc->memcg_low_skipped = 1; continue; -- 2.23.0 ref: test output: https://lkft.validation.linaro.org/scheduler/job/1489767#L1388 Test artifacts link (kernel / modules): https://builds.tuxbuild.com/5rRNgQqF_wHsSRptdj4A1A/ - Naresh
Powered by blists - more mailing lists