From 16b730a459ca744cd7d3d33954caaa43da8cb3a2 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Fri, 6 Dec 2019 10:54:23 -0600 Subject: fs: avoid softlockups in s_inodes iterators [ Upstream commit 04646aebd30b99f2cfa0182435a2ec252fcb16d0 ] Anything that walks all inodes on sb->s_inodes list without rescheduling risks softlockups. Previous efforts were made in 2 functions, see: c27d82f fs/drop_caches.c: avoid softlockups in drop_pagecache_sb() ac05fbb inode: don't softlockup when evicting inodes but there hasn't been an audit of all walkers, so do that now. This also consistently moves the cond_resched() calls to the bottom of each loop in cases where it already exists. One loop remains: remove_dquot_ref(), because I'm not quite sure how to deal with that one w/o taking the i_lock. Signed-off-by: Eric Sandeen Reviewed-by: Jan Kara Signed-off-by: Al Viro Signed-off-by: Sasha Levin --- fs/inode.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs/inode.c') diff --git a/fs/inode.c b/fs/inode.c index fef457a42882..96d62d97694e 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -676,6 +676,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) struct inode *inode, *next; LIST_HEAD(dispose); +again: spin_lock(&sb->s_inode_list_lock); list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) { spin_lock(&inode->i_lock); @@ -698,6 +699,12 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) inode_lru_list_del(inode); spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); + if (need_resched()) { + spin_unlock(&sb->s_inode_list_lock); + cond_resched(); + dispose_list(&dispose); + goto again; + } } spin_unlock(&sb->s_inode_list_lock); -- cgit v1.2.3