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Date: Tue, 11 Jul 2006 23:14:09 -0700 (PDT)
Message-Id: <20060711.231409.121242621.davem@davemloft.net>
To: kaos@ocs.com.au
Cc: linux-kernel@vger.kernel.org
Subject: Re: sparse annotation question
From: David Miller <davem@davemloft.net>
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References: <27360.1152683223@kao2.melbourne.sgi.com>
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From: Keith Owens <kaos@ocs.com.au>
Date: Wed, 12 Jul 2006 15:47:03 +1000

> func (long regno, unsigned long *contents)
> {
> 	unsigned long i, *bsp;
> 	mm_segment_t old_fs;
> 	bsp = <expression involving only kernel variables>;
> 	old_fs = set_fs(KERNEL_DS);
> 	for (i = 0; i < (regno - 32); ++i)
> 		bsp = ia64_rse_skip_regs(bsp, 1);
> 	put_user(*contents, bsp);
> 	set_fs(old_fs);
> }
> 
> sparse is complaining that the second parameter to put_user() is not
> marked as __user.  How do I tell sparse to ignore this case?  Marking
> bsp as __user does not work, sparse then complains about incorrect type
> in assignment (different address spaces).

Since, in this case, you "know what you are doing" you can force the
matter by using the __force keyword as well as __user.