ide=nodma has no effect

[Daniel Kulesz]

Binary package hint: linux-image-386

Actually it seems that the ide=nodma parameter has no effect when booting into the latest (2.6.28-6-386) kernel in jaunty. I am booting from a CF card using a IDE<->CF Adapter which does not support DMA. I get a lot of errors like this:

[ 116.356217] end_request: I/O error, dev hdb, sector 595

After a while, the kernel informs me then that DMA has been disabled, although specyfing ide=nodma (hdb=nodma didnt work either) I never asked the kernel to ever enable it.

Maybe these lines are also interesting:

[ 0.007288] Working around Cyrix MediaGX virtual DMA bugs.
[ 19.550485] ide0: BM-DMA at 0xf000-0xf007
[ 19.550753] ide1: BM-DMA at 0xf008-0xf00f

According to the last post in this thread (http://ubuntuforums.org/archive/index.php/t-9914.html) a possible solutions seems to be as follows:

--
Open the file "drivers/ide/ide.c" in the kernel source directory.
In this file, there's a global variable defined. Look for

int noautodma = 0;

and set it to 1. That's it.
--

This solution is of course inacceptable, I am not willing to patch the Kernel and maintain a custom Kernel image just because a boot parameter is not working.

[Andy Whitcroft (apw)]

A non-functional kernel parameter would be a real kernel bug and should be on the linux-ports (or even linux) package not the linux-ports-meta package. Shifting to the appropriate package.