init: fix read-write root mount

If mount flags don't have MS_RDONLY, iso9660 returns EACCES without actually
checking if it's an iso image.

This tricks mount_block_root() into retrying with MS_RDONLY.  This results
in a read-only root despite the "rw" boot parameter if the actual
filesystem was checked after iso9660.

I believe the behavior of iso9660 is okay, while that of mount_block_root()
is not.  It should rather try all types without MS_RDONLY and only then
retry with MS_RDONLY.

This change also makes the code more robust against the case when EACCES is
returned despite MS_RDONLY, which would've resulted in a lockup.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Miklos Szeredi 2014-11-20 16:08:59 +01:00 committed by Al Viro
parent 7d65cf10e3
commit 10975933da

View File

@ -395,8 +395,6 @@ void __init mount_block_root(char *name, int flags)
case 0:
goto out;
case -EACCES:
flags |= MS_RDONLY;
goto retry;
case -EINVAL:
continue;
}
@ -419,6 +417,10 @@ void __init mount_block_root(char *name, int flags)
#endif
panic("VFS: Unable to mount root fs on %s", b);
}
if (!(flags & MS_RDONLY)) {
flags |= MS_RDONLY;
goto retry;
}
printk("List of all partitions:\n");
printk_all_partitions();