Date: Fri, 25 Apr 2008 17:35:12 +0200 From: Joerg Sonnenberger <joerg@britannica.bec.de> To: freebsd-hackers@freebsd.org Subject: Re: CopyOut Size Limits Message-ID: <20080425153511.GB11467@britannica.bec.de> In-Reply-To: <DAB770F2-C987-4AEB-BD02-BD1AEF099702@signallake.com> References: <DAB770F2-C987-4AEB-BD02-BD1AEF099702@signallake.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Apr 25, 2008 at 09:59:55AM -0400, Adam wrote: > Hi, I am writing a custom system call that needs to transfer 16kb of data > from the kernel to userspace. I am transferring the data out of the kernel > by using copyout. This seems to work for a small struct of data < 4k. You are not allowed to use more than a bit of stack space. You are placing a of data on the stack and the kernel stack is typically only a few pages long. Use malloc for this. Joerg
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20080425153511.GB11467>