leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

memcg: swapout refcnt fix

Browse Source 
css's refcnt is dropped before end of following access.
Hold it until end of access.

Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KAMEZAWA Hiroyuki 2009-01-07 18:08:13 -08:00 committed by Linus Torvalds
parent b85a96c0b6
commit a7fe942e94
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
mm/memcontrol.c
View File

@ -1171,6 +1171,8 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
mz = page_cgroup_zoneinfo(pc); mz = page_cgroup_zoneinfo(pc);
unlock_page_cgroup(pc); unlock_page_cgroup(pc);
/* at swapout, this memcg will be accessed to record to swap */
if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
css_put(&mem->css); css_put(&mem->css);
return mem; return mem;
@ -1212,6 +1214,8 @@ void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent)
swap_cgroup_record(ent, memcg); swap_cgroup_record(ent, memcg);
mem_cgroup_get(memcg); mem_cgroup_get(memcg);
} }
if (memcg)
css_put(&memcg->css);
} }
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP