Re: [PATCH v2 0/3] bus: mhi: keep dma buffers through suspend/hibernation cycles

[Baochen Qiang <baochen.qiang@oss.qualcomm.com>]

On 7/15/2025 9:25 PM, Muhammad Usama Anjum wrote:
> When there is memory pressure during resume and no DMA memory is
> available, the ath11k driver fails to resume. The driver currently
> frees its DMA memory during suspend or hibernate, and attempts to
> re-allocate it during resume. However, if the DMA memory has been
> consumed by other software in the meantime, these allocations can
> fail, leading to critical failures in the WiFi driver. It has been
> reported [1].
> 
> Although I have recently fixed several instances [2] [3] to ensure
> DMA memory is not freed once allocated, we continue to receive
> reports of new failures.
> 
> In this series, 3 more such cases are being fixed. There are still
> some cases which I'm trying to fix. They can be discussed separately.
> 
> [1] https://lore.kernel.org/all/ead32f5b-730a-4b81-b38f-93d822f990c6@collabora.com
> [2] https://lore.kernel.org/all/20250428080242.466901-1-usama.anjum@collabora.com
> [3] https://lore.kernel.org/all/20250516184952.878726-1-usama.anjum@collabora.com
> 
> Muhammad Usama Anjum (3):
>   bus: mhi: host: keep bhi buffer through suspend cycle
>   bus: mhi: host: keep bhie buffer through suspend cycle
>   bus: mhi: keep device context through suspend cycles
> 
>  drivers/bus/mhi/host/boot.c     | 44 ++++++++++++++++++++-------------
>  drivers/bus/mhi/host/init.c     | 41 ++++++++++++++++++++++++++----
>  drivers/bus/mhi/host/internal.h |  2 ++
>  include/linux/mhi.h             |  2 ++
>  4 files changed, 67 insertions(+), 22 deletions(-)
> 

changelog missing