Comment 26 for bug 190492

I also confirm that the problem persists with 8.10 beta - I don't know if there has been more than one beta, so be informed that I used the iso CD image named ubuntu-8.10-beta-alternate-i386.iso, with md5sum 108696aafe01d4e90ee145c31ad05b82. I burned it to a new blank CD-R at low speed (8x), checked the CD for defects, and none was found.

With a normal boot, the HD is not detected.
With the pci=nomsi kernel parameter, the HD is detected (I didn't proceed to install the system though).

The motherboard is an ASUS a8v-x. The hard disk is SATA. In the BIOS setup, the item 'Serial ATA IDE controller' is configured as 'SATA'; the options are 'Disabled', 'SATA', 'RAID' and 'AHCI'. Changing to 'AHCI' didn't seem to help. I have not tried 'RAID', nor (obviously) 'Disabled'.

I have attached, in .tar.gz format, the output of dmesg, lsmod, lspci -vv, /proc/cmdline and /proc/cpuinfo for two situations: with a normal boot (except that I removed the 'quiet' kernel parameter) and a boot with the 'pci=nomsi' kernel parameter (and 'quiet' removed too). In both cases, I booted with the alternate CD, chose English language, Brazilian keymap, edited the boot parameters, then allowed the installer to reach its first prompt. Then I switched into a virtual console and gathered the previously mentioned information, saving it into a pen drive.

My attempt to install Linux in that computer involved Ubuntu 8.04 (failed to install), then Ubuntu 7.10 (failed to install), then Debian Etch. Debian Etch installed successfully, but was unstable. KDE would sometimes abruptly disappear and the system would go back to KDM. Then, since NTFS-3g complained that Debian Etch's 2.6.18 kernel was too old, I tried 2.6.24. Didn't work, with error messages similar to Ubuntu. I tried 2.6.26 from Lenny, with the same problem. I then read http://en.wikipedia.org/wiki/Ahci#Common_problems_switching_to_AHCI_under_Linux, saw that VT8251 is faulty, confirmed that this chip is present on the computer, and tried the pci=nomsi workaround. Now the Debian system seems to work stably (and NTFS-3g works without complaints).

I beg you to mention this bug in the Intrepid Release Notes, along with the pci=nomsi workaround. And it should be explained wether or not this workaround has bad side effects (I don't know. I have read the MSI-HOWTO.txt from the kernel documentation, but I still don't know if pci=nomsi is safe).

Of course, making the installer automatically detect the faulty chip and work around the problem would be excellent, if viable. Even better would be to change the kernel itself.

Of course, if you make any additional information request, I will respond as quickly as possible.
Thank you for working in this excellent OS,
     Jorge Peixoto from Brasil