f2fs: Fix deadlock in shutdown ioctl

f2fs_ioc_shutdown() ioctl gets stuck in the below path
when issued with F2FS_GOING_DOWN_FULLSYNC option.

__switch_to+0x90/0xc4
percpu_down_write+0x8c/0xc0
freeze_super+0xec/0x1e4
freeze_bdev+0xc4/0xcc
f2fs_ioctl+0xc0c/0x1ce0
f2fs_compat_ioctl+0x98/0x1f0

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Sahitya Tummala 2018-05-18 11:51:52 +05:30 committed by Jaegeuk Kim
parent f8de433122
commit 60b2b4ee2b
1 changed files with 7 additions and 4 deletions

View File

@ -1857,9 +1857,11 @@ static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
if (get_user(in, (__u32 __user *)arg))
return -EFAULT;
ret = mnt_want_write_file(filp);
if (ret)
return ret;
if (in != F2FS_GOING_DOWN_FULLSYNC) {
ret = mnt_want_write_file(filp);
if (ret)
return ret;
}
switch (in) {
case F2FS_GOING_DOWN_FULLSYNC:
@ -1900,7 +1902,8 @@ static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
f2fs_update_time(sbi, REQ_TIME);
out:
mnt_drop_write_file(filp);
if (in != F2FS_GOING_DOWN_FULLSYNC)
mnt_drop_write_file(filp);
return ret;
}