x86: Always use irq stacks

IRQ stacks provide much better safety against unexpected stack use from
interrupts, at the minimal downside of slightly higher memory usage.
Enable irq stacks also for the default 8k stack on 32-bit kernels to
minimize the problem of stack overflows through interrupt activity.

This is what the 64-bit kernel and various other architectures already do.

Signed-off-by: Christoph Hellwig <hch@lst.de>
LKML-Reference: <20100628121554.GA6605@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 3 insertions, 3 deletions

diff --git a/Documentation/x86/x86_64/kernel-stacks b/Documentation/x86/x86_64/kernel-stacks
index 5ad65d51fb95..a01eec5d1d0b 100644
--- a/Documentation/x86/x86_64/kernel-stacks
+++ b/Documentation/x86/x86_64/kernel-stacks
@@ -18,9 +18,9 @@ specialized stacks contain no useful data.  The main CPU stacks are:
   Used for external hardware interrupts.  If this is the first external
   hardware interrupt (i.e. not a nested hardware interrupt) then the
   kernel switches from the current task to the interrupt stack.  Like
-  the split thread and interrupt stacks on i386 (with CONFIG_4KSTACKS),
-  this gives more room for kernel interrupt processing without having
-  to increase the size of every per thread stack.
+  the split thread and interrupt stacks on i386, this gives more room
+  for kernel interrupt processing without having to increase the size
+  of every per thread stack.
 
   The interrupt stack is also used when processing a softirq.