Re: Syscall from Kernel Space

[Andrea Arcangeli <andrea@suse.de>]

On Thu, Feb 20, 2003 at 12:40:43PM -0500, Jeff Garzik wrote:
> On Thu, Feb 20, 2003 at 11:04:37PM +0530, Prasad wrote:
> > 	Is there a way using which i could invoke a syscall in the kernel 
> > space?  The syscall is to be run disguised as another process.  The actual 
> 
> Call sys_<syscall>.  Look at the kernel code for examples.
> 
> Note that typically you don't want to do this... and you _really_ don't
> want to do this if the syscall is not one of the common file I/O
> syscalls (read/write/open/close, etc.)

you never want to do this, the only point of a syscall is to enter
kernel, if you're just in kernel you're wasting time in calling the
syscall (not to tell about the new non soft interrupt based syscall
instructions, btw this is also why I rejected the int 0x81 thing on
x86-64 for 64bit syscalls)

Andrea