KVM Windows 98 sound card passthrough is not working for DOS programs..

This bug has been copied automatically from: https://bugs.launchpad.net/qemu/+bug/1873344

Hello,
im trying to passthrough PCI soundcards into Qemu Windows 98 machine - i
tried Yamaha 724/744 and Aunreal Vortex 1, for Windows 98 its working
fine, but for Windows 98 dosbox mode its at the best half - working - FM
(music) only or nothing with detected by games sound setups.
  All there cards are using SB emulation devices.

  When i try to boot to pure DOS, without Windows 98, even music is not
working with pass through, only sound which i was able to heard its form
Yamaha Setup utility test - Native 16bit sound, aby other test, games
setup etc.. are able to dettect sound cards at all.
  Im pretty sure that drivers are setup correctly, because im using same
setup on other physical machine, when its working. My suspect is missing
or broken Qemu MB DMA channels emulation.. Because its is need to make DOS
sound working.

  Im using pass through because, SB16 emulation in Qemu is incomplete and
for Windows 98 dos box, problem is same as with physical cards. Same with
AC97 emulation and its Win95 drivers, which have SB emulation device
fallback..

Qemu 2.11 + 4.2 Linux Mint 19.3. MB Gigabyte Z170.