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Subject[PATCH] mm: gup: fix access_ok() argument type
Date
MIPS just got changed to only accept a pointer argument for access_ok(),
causing one warning in drivers/scsi/pmcraid.c. I tried changing x86
the same way and found the same warning in __get_user_pages_fast()
and nowhere else in the kernel during randconfig testing:

mm/gup.c: In function '__get_user_pages_fast':
mm/gup.c:1578:6: error: passing argument 1 of '__chk_range_not_ok' makes pointer from integer without a cast [-Werror=int-conversion]

It would probably be a good idea to enforce type-safety in general,
so let's change this file to not cause a warning if we do that.

I don't know why the warning did not appear on MIPS.

Fixes: 2667f50e8b81 ("mm: introduce a general RCU get_user_pages_fast()")
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
mm/gup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/gup.c b/mm/gup.c
index 2559a3987de7..7f5bc26d9229 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1575,7 +1575,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
end = start + len;

if (unlikely(!access_ok(write ? VERIFY_WRITE : VERIFY_READ,
- start, len)))
+ (void __user *)start, len)))
return 0;

/*
--
2.9.0
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