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arm: fix put_user sparse errors

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virtio wants to write bitwise types to userspace using put_user.
At the moment this triggers sparse errors, since the value is passed
through an integer.

For example:

	__le32 __user *p;
	__le32 x;
	put_user(x, p);

is safe, but currently triggers a sparse warning.

Fix that up using __force.

Note: this does not suppress any useful sparse checks since caller
assigns x to typeof(*p), which in turn forces all the necessary type
checks.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Michael S. Tsirkin 2015-01-06 14:37:22 +02:00
parent 09a2f7cf6a
commit e8b94dea38
1 changed files with 2 additions and 2 deletions
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4
arch/arm/include/asm/uaccess.h
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@ -413,14 +413,14 @@ do { \
#ifndef __ARMEB__
#define __put_user_asm_half(x,__pu_addr,err) \
({ \
unsigned long __temp = (unsigned long)(x); \
unsigned long __temp = (__force unsigned long)(x); \
__put_user_asm_byte(__temp, __pu_addr, err); \
__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
})
#else
#define __put_user_asm_half(x,__pu_addr,err) \
({ \
unsigned long __temp = (unsigned long)(x); \
unsigned long __temp = (__force unsigned long)(x); \
__put_user_asm_byte(__temp >> 8, __pu_addr, err); \
__put_user_asm_byte(__temp, __pu_addr + 1, err); \
})