diff options
authorChristophe Leroy <>2021-05-14 17:27:39 -0700
committerLinus Torvalds <>2021-05-14 19:41:32 -0700
commit86d0c164272536c732853e19391de5159f860701 (patch)
parentf4d3f25aced3b493e57fd4109e2bc86f0831b23e (diff)
mm/ioremap: fix iomap_max_page_shift
iomap_max_page_shift is expected to contain a page shift, so it can't be a 'bool', has to be an 'unsigned int' And fix the default values: P4D_SHIFT is when huge iomap is allowed. However, on some architectures (eg: powerpc book3s/64), P4D_SHIFT is not a constant so it can't be used to initialise a static variable. So, initialise iomap_max_page_shift with a maximum shift supported by the architecture, it is gated by P4D_SHIFT in vmap_try_huge_p4d() anyway. Link: Fixes: bbc180a5adb0 ("mm: HUGE_VMAP arch support cleanup") Signed-off-by: Christophe Leroy <> Reviewed-by: Nicholas Piggin <> Reviewed-by: Anshuman Khandual <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
1 files changed, 3 insertions, 3 deletions
diff --git a/mm/ioremap.c b/mm/ioremap.c
index d1dcc7e744ac..8ee0136f8cb0 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -16,16 +16,16 @@
#include "pgalloc-track.h"
-static bool __ro_after_init iomap_max_page_shift = PAGE_SHIFT;
+static unsigned int __ro_after_init iomap_max_page_shift = BITS_PER_LONG - 1;
static int __init set_nohugeiomap(char *str)
- iomap_max_page_shift = P4D_SHIFT;
+ iomap_max_page_shift = PAGE_SHIFT;
return 0;
early_param("nohugeiomap", set_nohugeiomap);
-static const bool iomap_max_page_shift = PAGE_SHIFT;
+static const unsigned int iomap_max_page_shift = PAGE_SHIFT;
int ioremap_page_range(unsigned long addr,