As reported on the Linux Kernel Mailing List (see Posting http://lkml.org/lkml/2007/3/23/312 ) in March 2007, there is a regression in kernel 2.6.21-rc4 which makes booting from the LSI MPT SCSI-controller impossible. Unfortunately, this is exactly the type of SCSI-controller VMware Virtual Machines use by default for virtual harddisks. Which means, VMs using gentoo-sources-2.6.21-r4 can no longer boot from emulated SCSI disks. Reproducible: Always Steps to Reproduce: 1.Install gentoo-sources-2.6.21-r4 on a VMware VM using SCSI disk emulation 2.Reboot 3. Actual Results: After reboot, the kernel panicks complaining it cannot find the root device. Expected Results: Just boot the system as it did before gentoo-sources-2.6.21-r4 gentoo-sources-2.6.21-r4 should either be marked as unstable, or additional patches must be added to fix the problem. In its current form, a "stable" Gentoo Installation on a VMware VM will be rendered unusable with the newly installed kernel after a restart. As the bug only affects VMs using SCSI disk emulation, VMs using IDE disk emulations will not be affected. It should be noted, though, that SCSI disk emulation is the recommended choice by the VMware Disk Creation Wizard when creating new virtual hard disks. Also, *real* machines using the same LSI SCSI-controller will be affected as well, of course.
kernel issues are not a genkernel bug.
(In reply to comment #1) > kernel issues are not a genkernel bug. Sorry for that! I could not find a better place to file it, and as genkernel is based on gentoo-sources I thought it might still apply. There was no "gentoo-sources" entry in the "Gentoo Hosted Projects" product category, but I felt gentoo-sources *is* a Gentoo Hosted Project. Obviously, I was wrong.
*** This bug has been marked as a duplicate of bug 185272 ***