On Tue, Apr 26, 2005 at 12:04:00PM -0400, Alan Stern wrote:
> > Sure there is. Every IRQ line goes to an IRQ controller.
> > Arch specific code deals with programming the controller and can
> > mask all interrupts (or not). Historically, they've been left unmasked
> > for ISA IRQ discovery and debugging misrouted IRQ lines.
>
> This doesn't help. Consider what happens when two devices share an IRQ
> line. Suppose device B is generating interrupt requests when the driver
> for device A is probed. The driver registers its handler, which causes
> the IRQ line to be unmasked. Then a multitude of IRQs arrive from B, none
> of which can be handled by A's driver. So the kernel shuts the IRQ line
> down permanently...
Agreed - but this is a different problem than "shutting down IRQs".
My point was arch specific code knows how to mask all IRQs.
irq_disable() is expected to work regardless of what state the
driver is in. On kexec "reboot", kernel drivers can unmask IRQs
as they normally would during initialization. No?
grant
-
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]