On Sun, Feb 07, 2021 at 03:46:43PM +0800, Chao Yu wrote: > Hi Eric, > > On 2021/1/16 2:18, Eric Biggers wrote: > > +static int f2fs_ioc_read_verity_metadata(struct file *filp, unsigned long arg) > > +{ > > + if (!f2fs_sb_has_verity(F2FS_I_SB(file_inode(filp)))) > > + return -EOPNOTSUPP; > > One case is after we update kernel image, f2fs module may no longer support > compress algorithm which current file was compressed with, to avoid triggering > IO with empty compress engine (struct f2fs_compress_ops pointer): > > It needs to add f2fs_is_compress_backend_ready() check condition here? > > Thanks, > > > + > > + return fsverity_ioctl_read_metadata(filp, (const void __user *)arg); > > +} In that case it wouldn't have been possible to open the file, because f2fs_file_open() checks for it. So it's not necessary to repeat the same check in every operation on the file descriptor. - Eric