Re: PATCH 2.4.0.9.2: export ethtool interface

[Andrew Morton <andrewm@xxxxxxxxxx>]

Hi, Andi.

Andi Kleen wrote:
> 
> ..
> > Yes.  On 2.4 (at least) there is nothing to prevent the driver's ioctl()
> > function from running on two or more CPUs simultaneously.
> 
> There is (2.4.0test9pre2):
> 
> asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long 
> arg)
> {
>         struct file * filp;
>         unsigned int flag;
>         int on, error = -EBADF;
> 
>         filp = fget(fd);
>         if (!filp)
>                 goto out;
>         error = 0;
>         lock_kernel();                   <--------------
>         switch (cmd) {
> 

But sys_ioctl calls....

int sock_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
            unsigned long arg)
{
        struct socket *sock;
        int err;

        unlock_kernel();                   <---------------
        sock = socki_lookup(inode);
        sock = socki_lookup(inode);
        err = sock->ops->ioctl(sock, cmd, arg);