Re: [patch] "big IRQ lock" removal, 2.5.27-A9

Ingo Molnar
2002-07-21T21:54:11Z

On Sun, 21 Jul 2002, Christoph Hellwig wrote:

> > the genhd.c bit is safe as well, removed the comment.
>
> Is there any reason the sti is there at all? In -dj almost all drivers
> use module_init() now so it becomes increasingly useless..

well, indeed. While the sti() can be understood to a certain degree - we
used to boot with the IRQ lock on and accidentally leaving it enabled can
cause problems - but otherwise preceeding code should not disable
interrupts in an unbalanced way. I've removed the __sti() from my tree.

there's even more ancient code in the block driver init path, eg. in
drivers/block/ll_rw_blk.c:blk_dev_init():

outb_p(0xc, 0x3f2);

i suspect this is ancient Linux code. 0x3f2 is one of the floppy
controller ports - many modern x86 boxes do not even have a floppy
controller! I've removed this from my tree as well - if this is needed at
all then it belongs into the floppy driver. Latest patch is at:

http://redhat.com/~mingo/remove-irqlock-patches/remove-irqlock-2.5.27-B0

Ingo