Re: d_lookup: Unable to handle kernel paging request

[Al Viro <viro@xxxxxxxxxxxxxxxxxx>]

On Wed, Jun 19, 2019 at 06:51:51PM +0200, Vicente Bergas wrote:

> > What's your config, BTW?  SMP and DEBUG_SPINLOCK, specifically...
> 
> Hi Al,
> here it is:
> https://paste.debian.net/1088517

Aha...  So LIST_BL_LOCKMASK is 1 there (same as on distro builds)...

Hell knows - how about
static inline void hlist_bl_lock(struct hlist_bl_head *b)
{
	BUG_ON(((u32)READ_ONCE(*b)&~LIST_BL_LOCKMASK) == 0x01000000);
        bit_spin_lock(0, (unsigned long *)b);
}

and

static inline void hlist_bl_unlock(struct hlist_bl_head *b)
{
        __bit_spin_unlock(0, (unsigned long *)b);
	BUG_ON(((u32)READ_ONCE(*b)&~LIST_BL_LOCKMASK) == 0x01000000);
}

to see if we can narrow down where that happens?