Re: Promise PDC20376

From: David Ellingsworth
Date: Mon Dec 01 2008 - 20:43:51 EST

> > Since I put this out there, I felt it was important to follow-up on so
> > others could benefit from my experiences. After extensive testing, the
> > cause of the problems I've experienced are a result of a bug in the
> > Fasttrak bios for the Promise 376 controller. Specifically speaking,
> > bios interrupt 13h, AH=42 fails to read the requested sector from the
> > drive despite the fact that bios interrupt 13h, AH=41, BX=0x55AA
> > indicates the drive supports LBA extensions. The only known
> > work-around at this time is to limit the size of the primary boot
> > partition to 8GB or less and place it below the 8GB boundary where LBA
> > extensions are not required to read the drive. I have contacted
> > Promise concerning this issue and will provide more updates if
> > anything metabolizes. Until then any users experiencing similar issues
> > should use the work-around I've described above to boot the operating
> > system of their choice.
> For booting with grub only /boot needs to be accessible by the BIOS,
> so it's common to make /boot a separate partition early on the disk
> with / and other partitions higher up.
> This is the first I've heard of any Promise SATA controller having
> such lame limitations.

A small update to this. It seems the above mentioned interrupt fails
somewhere around the 128GB boundary. Interrupt 13h, AH=42 uses a 64
bit sector address and should be capable of addressing the entire
drive. For a SATA controller, this limitation seems relatively
arbitrary. For IDE controllers, a limitation such as this is
apparently common.


David Ellingsworth
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at