Comment 73 for bug 442194

In broken case (11.0 dmesg) PATA and SATA via share IRQ 20 (which should
be taken by the network card):

<7>pata_via 0000:00:0f.1: version 0.3.3
<6>ACPI: PCI Interrupt 0000:00:0f.1[A] -> GSI 20 (level, low) -> IRQ 20
...
<6>ACPI: PCI Interrupt 0000:00:0f.0[B] -> GSI 20 (level, low) -> IRQ 20
<6>sata_via 0000:00:0f.0: routed to hard irq line 10

This:
<6>sata_via 0000:00:0f.0: routed to hard irq line 10
Is what pci config says which IRQ should be taken in hex and this is what is done
on 10.3:

<6>ACPI: PCI Interrupt 0000:00:0f.0[B] -> GSI 20 (level, low) -> IRQ 16
<6>sata_via 0000:00:0f.0: routed to hard irq line 10
...
<7>pata_via 0000:00:0f.1: version 0.3.1
<6>ACPI: PCI Interrupt 0000:00:0f.1[A] -> GSI 20 (level, low) -> IRQ 16
<6>scsi2 : pata_via

Hmm, the order of pata_via and sata_via load time is exchanged. Just an idea, but you could try to blacklist pata_via (in /etc/modprobe.conf.local):
blacklist pata_via
-> then run mkinitrd and reboot
to enable it again remove the line from modprobe.conf.local and run mkinitrd again.