Re: linux-next: Tree for Jan 20 -- Kernel panic - Unable to mount root fs
On Tue, Jan 20, 2015 at 07:14:46PM -0500, Paul Moore wrote:
> > with the patch applied (+panic)
> >
> >
> > and:
> >
> > stat("/dev/root") -> 0
> > stat("dev") -> 0
> > with the old version of do_path_lookup.
>
> Wait a minute ... at this early stage of boot, I'm pretty sure we don't
have
> a valid current->audit_context since we haven't fork'd anything. If the
> audit context was non-NULL garbage that might explain the panic ...
Not really - the panic is predicatable result of not finding /dev/root (hell,
not even /dev there!) in mount_block_root().
Could you try initializing the init_task's audit_context to NULL
in the
INIT_TASK macro in include/linux/init_task.h?
Missing fields in struct initializer are treated as zeroes.
The shit hits the fan earlier - when we end up missing /dev. There are
two places where it could've been created (depending on CONFIG_BLK_DEV_INITRD);
sys_mkdir(collected, mode);
in init/initramfs.c (line 353 in linux-next) and
err = sys_mkdir((const char __user __force *) "/dev", 0755);
in init/noinitramfs.c (line 32). The latter would've screamed on failure;
could you printk of collected (%s), mode (%o) and return value (%d) in the
former and see what happens?