On Tue, Sep 03, 2019 at 06:04:56AM -0700, Christoph Hellwig wrote: > On Tue, Sep 03, 2019 at 01:37:19PM +0100, Al Viro wrote: > > On Tue, Sep 03, 2019 at 12:21:36AM -0400, Qian Cai wrote: > > > The linux-next commit "fs/namei.c: keep track of nd->root refcount status” [1] causes boot panic on all > > > architectures here on today’s linux-next (0902). Reverted it will fix the issue. > > > > <swearing> > > > > OK, I see what's going on. Incremental to be folded in: > > > > diff --git a/include/linux/namei.h b/include/linux/namei.h > > index 20ce2f917ef4..2ed0942a67f8 100644 > > --- a/include/linux/namei.h > > +++ b/include/linux/namei.h > > @@ -20,8 +20,8 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; > > #define LOOKUP_FOLLOW 0x0001 /* follow links at the end */ > > #define LOOKUP_DIRECTORY 0x0002 /* require a directory */ > > #define LOOKUP_AUTOMOUNT 0x0004 /* force terminal automount */ > > -#define LOOKUP_EMPTY 0x4000 /* accept empty path [user_... only] */ > > -#define LOOKUP_DOWN 0x8000 /* follow mounts in the starting point */ > > +#define LOOKUP_EMPTY 0x8000 /* accept empty path [user_... only] */ > > +#define LOOKUP_DOWN 0x10000 /* follow mounts in the starting point */ > > > > #define LOOKUP_REVAL 0x0020 /* tell ->d_revalidate() to trust no cache */ > > #define LOOKUP_RCU 0x0040 /* RCU pathwalk mode; semi-internal */ > > Any chance to keep these ordered numerically to avoid someone else > introdcing this kind of bug again later on? Not sure what would be the best way to do it... I don't mind breaking the out-of-tree modules, whatever their license is; what I would rather avoid is _quiet_ breaking of such.