Re: [RFC PATCH 0/2] Enhance RPMsg buffer management

[Tanmay Shah <tanmay.shah@amd.com>]

On 12/17/25 3:31 PM, Mathieu Poirier wrote:
> On Fri, Nov 14, 2025 at 10:46:38AM -0800, Tanmay Shah wrote:
>> Take rx and tx buffer size from virtio device config space in the
>> resource table. This allows each firmware to configure RPMsg buffer size
>> as needed in each direction.
>>
>> Original seris:
>> https://lore.kernel.org/all/1548949280-31794-1-git-send-email-xiaoxiang@xiaomi.com/
>>
>> Following modificaitons are done to the original series:
>>   - Separate dma allocation is not done for tx and rx buffers. Instead
>>     allocated chunk of memory is split between tx and rx buffers.
>>   - If vdev doesn't support VIRTIO_RPMSG_F_BUFSZ feature then use the 
>>     default size of 512 bytes for buffers
>>   - Change MAX_RPMSG_BUF_SIZE to DEFAULT_RPMSG_BUF_SIZE
>>   - move virtio_rpmsg.h from uapi to linux dir
>>   - RPMsg buffer size must be set to hold rpmsg header at minimum in the
>>     vdev config space of the firmware.
>>   - align total buf size to page size when allocating and deallocating
>>     memory
>>
>> Xiang Xiao (2):
>>   rpmsg: virtio_rpmsg_bus: allow the different vring size for send/recv
>>   rpmsg: virtio_rpmsg_bus: get buffer size from config space
>>
>>  drivers/rpmsg/virtio_rpmsg_bus.c | 105 ++++++++++++++++++++-----------
>>  include/linux/virtio_rpmsg.h     |  24 +++++++
>>  2 files changed, 93 insertions(+), 36 deletions(-)
>>  create mode 100644 include/linux/virtio_rpmsg.h
>>
> 
> This set is going somewhere.  Please address the comments that were received and
> send a new revision.
> 
> Apologies for the long review delay.
> Mathieu
>  

Sure Mathieu, no problem. I will be on leave in the January, and will start
working on this patch series once I come back.

Thanks,
Tanmay

>>
>> base-commit: f982fbb1a6ca3553c15763ad9eb2beeae78d3684
>> -- 
>> 2.34.1
>>