Where to file bug report?

Yesterday I had a second VM guest fail. The day before one failed in the same way. Both suddenly had read only file systems. In both cases these are the last lines in the syslog:

Sep  7 21:19:59 dev init: tty (/dev/tty1) main process ended, respawning
Sep  7 21:59:23 dev kernel: ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
Sep  7 21:59:23 dev kernel: ata1.00: failed command: WRITE DMA
Sep  7 21:59:23 dev kernel: ata1.00: cmd ca/00:08:a0:02:31/00:00:00:00:00/e3 tag 0 dma 4096 out
Sep  7 21:59:23 dev kernel:         res 40/00:01:00:00:00/00:00:00:00:00/a0 Emask 0x4 (timeout)
Sep  7 21:59:23 dev kernel: ata1.00: status: { DRDY }
Sep  7 21:59:23 dev kernel: ata1: soft resetting link
Sep  7 21:59:23 dev kernel: ata1.00: configured for MWDMA2
Sep  7 21:59:23 dev kernel: ata1.00: device reported invalid CHS sector 0
Sep  7 21:59:23 dev kernel: ata1: EH complete

I assume this is the reason the root was suddenly read only.

I am running updated CentOS 6 on the host and all guests. Which list should I search and/or report this to? Kernel or kvn?

Emmett