Re: [RFC] ps command race fix

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, 24 Jul 2006 18:48:47 -0700
Paul Jackson <[email protected]> wrote:

> Another possibility (perhaps a really stupid idea ;) would be to
> snapshot the list of pids on the open, and let the readdir() just
> access that fixed array.

The patch under discussion does precisely this.  (Awkwardly.  Using
kmalloc-pre-object might be better).

> The kernel/cpuset.c cpuset_tasks_open() routine that displays the
> pids of tasks in a cpuset (the per-cpuset 'tasks' file) does this.

Your faith in large kmalloc()s is touching ;) I guess the number of pids
will be smaller for cpusets.

> Then the seek and read and such semantics are nice and stable and
> simple.
> 
> Throw out the snapshot on the last close.

The patch under discussion didn't do this, although it could.  But it still
permits rather a lot of kernel memory to be pinned.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux