ACK: [PATCH 0/6][SRU][K] Fix No HDMI audio under 5.19.0-35 & -37 (regression from -32)

[Cory Todd]

On Fri, Mar 24, 2023 at 05:43:56PM +0800, Koba Ko wrote:
> BugLink: https://bugs.launchpad.net/bugs/2009136
> 
> [Impact]
> For amdgpu/i915, hdmi audio output device has disappeared.
> 
> [Fix]
> The latest fix for the non-contiguous memalloc helper changed the
> allocation method for a non-IOMMU system to use only the fallback
> allocator. This should have worked, but it caused a problem sometimes
> when too many non-contiguous pages are allocated that can't be treated
> by HD-audio controller.
> 
> As a quirk workaround, go back to the original strategy: use
> dma_alloc_noncontiguous() at first, and apply the fallback only when
> it fails, but only for non-IOMMU case
> 
> [Test Case]
> 1. boot with kernel applied the patches.
> 2. check the cards in /proc/asound/cards.
>    Get the hdmi cards.
> 
>  0 [PCH ]: HDA-Intel - HDA Intel PCH
>                       HDA Intel PCH at 0xe2320000 irq 137
>  1 [HDMI ]: HDA-Intel - HDA ATI HDMI
>                       HDA ATI HDMI at 0xe2260000 irq 134
> 
> [Where problems could occur]
> Low, this is just workaround and may have a better solution in the future.
> 
> [Misc]
> All patches has been landed on OEM-6.1 and lunar.
> 
> 
> Takashi Iwai (6):
>  ALSA: memalloc: Try dma_alloc_noncontiguous() at first
>  ALSA: memalloc: Drop special handling of GFP for CONTINUOUS
>     allocation
>  ALSA: vx: Drop superfluous GFP setup
>  ALSA: pdaudiocf: Drop superfluous GFP setup
>  ASoC: Intel: sst: Switch to standard device pages
>  ALSA: memalloc: Workaround for Xen PV
> 
>  include/sound/memalloc.h                     |   3 -
>  sound/core/memalloc.c                        | 230 +++++++++++--------
>  sound/drivers/vx/vx_pcm.c                    |   3 +-
>  sound/pcmcia/pdaudiocf/pdaudiocf_pcm.c       |   3 +-
>  sound/soc/intel/atom/sst-mfld-platform-pcm.c |   7 +-
>  5 files changed, 142 insertions(+), 104 deletions(-)
> 
Acked-by: Cory Todd <cory.todd at canonical.com>