slab,slub: don't enable interrupts during early boot

As explained by Benjamin Herrenschmidt:

  Oh and btw, your patch alone doesn't fix powerpc, because it's missing
  a whole bunch of GFP_KERNEL's in the arch code... You would have to
  grep the entire kernel for things that check slab_is_available() and
  even then you'll be missing some.

  For example, slab_is_available() didn't always exist, and so in the
  early days on powerpc, we used a mem_init_done global that is set form
  mem_init() (not perfect but works in practice). And we still have code
  using that to do the test.

Therefore, mask out __GFP_WAIT, __GFP_IO, and __GFP_FS in the slab allocators
in early boot code to avoid enabling interrupts.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/slob_def.h b/include/linux/slob_def.h
index 0ec00b39d00..bb5368df4be 100644
--- a/include/linux/slob_def.h
+++ b/include/linux/slob_def.h
@@ -34,4 +34,9 @@ static __always_inline void *__kmalloc(size_t size, gfp_t flags)
 	return kmalloc(size, flags);
 }
 
+static inline void kmem_cache_init_late(void)
+{
+	/* Nothing to do */
+}
+
 #endif /* __LINUX_SLOB_DEF_H */