> -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@xxxxxxxxxx] > Sent: Tuesday, June 30, 2015 2:40 AM > To: linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: Jaegeuk Kim > Subject: [f2fs-dev] [PATCH 08/12] f2fs: introduce a shrinker for mounted fs > > This patch introduces a shrinker targeting to reduce memory footprint consumed > by a number of in-memory f2fs data structures. > > In addition, it newly adds: > - sbi->umount_mutex to avoid data races on shrinker and put_super > - sbi->shruinker_run_no to not revisit objects > > Noteh that the basic implementation was copied from fs/btrfs/shrinker.c This file seems not exist... > @@ -1310,6 +1328,7 @@ free_root_inode: > dput(sb->s_root); > sb->s_root = NULL; > free_node_inode: > + f2fs_leave_shrinker(sbi); We should detach shrinker under sbi->umount_mutex. Otherwise we will access freed memory in following call path: mount shrinker ->fill_super Failed after f2fs_join_shrinker ->f2fs_leave_shrinker ->f2fs_shrink_scan spin_lock get sbi pointer spin_unlock spin_lock list_del sbi->s_list spin_unlock free sbi use-after-free for sbi Thanks, -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
