[syslinux] lpxelinux.0 with device that doesn't support Interrupts

Wissam Shoukair wissams at mellanox.com
Fri Feb 26 15:10:10 PST 2016

I am experiencing an issue where I ran ipxe (as an option rom) and downloaded the lpxelinux.0 as the bootloader.
Next it should download the ldlinux.c32 file using UNDI API.
but before that it will close and open  the underlying device (which is ipxe), and hooking the device interrupt so it can start getting some packets.

What I'm experiencing is that if the underlying device doesn't support interrupts, i.e. the IntNumber that is returned in PXENV_UNDI_GET_INFORMATION is 0, then lpxelinux.0 will hook IRQ0 which is very bad behavior.

one good example of the faulty code is in undinet.c where we open a device, we hook the IRQ regardless if its 0 or not, while in the latest iPXE code this behavior was corrected and a check expression was added to avoid such bad behavior

-----Original Message-----
From: Syslinux [mailto:syslinux-bounces at zytor.com] On Behalf Of Geert Stappers via Syslinux
Sent: Friday, February 26, 2016 15:35
To: syslinux at zytor.com
Subject: Re: [syslinux] lpxelinux.0 with device that doesn't support Interrupts

On Fri, Feb 26, 2016 at 01:00:21PM +0000, Wissam Shoukair via Syslinux wrote:
> hi
> does anyone know if there are some known issues with running 
> lpxelinux.0 with device that doesn't support Interrupts?
> i.e. irq function is null...

Take some time to elaborate the question.

Geert Stappers
Who thinks that Original Poster  doesn't want to hear/read issues.
Syslinux mailing list
Submissions to Syslinux at zytor.com
Unsubscribe or set options at:

More information about the Syslinux mailing list