Date: Sat, 24 Jun 2000 23:38:30 -0700 (PDT) From: Gerry Bash <gersh@sonn.com> To: Matthew Jacob <mjacob@feral.com> Cc: freebsd-alpha@FreeBSD.ORG Subject: Re: Alpha memory managment fault questions Message-ID: <Pine.BSI.4.05L.10006242335360.11986-100000@cara.sonn.com> In-Reply-To: <Pine.BSF.4.10.10006242323340.1165-100000@beppo.feral.com>
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Oh good point.
I changed it to use a copyinstr and all works fine, Thanks alot.
On Sat, 24 Jun 2000, Matthew Jacob wrote:
>
> What makes you think uap->fname is in the kernel's address space?
> The pointer uap points to arguments that are in user space.
>
> Coincidentally on some platforms or implementations you can refer to them
> directly in the part of the kernel that is in a direct call path from a
> syscall. But this is not guaranteed. In fact, the PDP-11/{45,70}
> implementation of Unix had user and kernel in completely different address
> spaces that required the use of special instructions to copy bytes between
> them (e.g., MFPD (move from previous data space)).
>
> If you want to print fname in the kernel, what function do you want to use
> to assist in printing it?
>
> [ hint- you should follow the call path to namei from execve ]
>
> -matt
>
>
>
>
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