Re: [PATCH v1 2/5] misc: fastrpc: Move all remote heap allocations to a new list

[Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>]

On 5/19/2025 3:46 PM, Dmitry Baryshkov wrote:
> On Tue, May 13, 2025 at 09:58:22AM +0530, Ekansh Gupta wrote:
>> Remote heap allocations are not organized in a maintainable manner,
>> leading to potential issues with memory management. As the remote
> Which issues? I think I have been asking this question previously.
> Please expand the commit message here.
This is mostly related to the memory clean-up and the other patch where
unmap request was added, I'll try to pull more details about the issue
scenario.
>
>> heap allocations are maintained in fl mmaps list, the allocations
>> will go away if the audio daemon process is killed but there are
> What is audio daemon process?
As audio PD on DSP is static, there is HLOS process(audio daemon) required to
attach to audio PD to fulfill it's memory and file operation requirements.

This daemon can be thought of to be somewhat similar to rootPD(adsprpcd) or
sensorsPD(sscrpcd) daemons. Although, there is a slight difference in case of audio
daemon as it is required to take additional information and resources to audio PD
while attaching.

//Ekansh
>
>> chances that audio PD might still be using the memory. Move all
>> remote heap allocations to a dedicated list where the entries are
>> cleaned only for user requests and subsystem shutdown.
>>
>> Fixes: 0871561055e66 ("misc: fastrpc: Add support for audiopd")
>> Cc: stable@kernel.org
>> Signed-off-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
>> ---
>>  drivers/misc/fastrpc.c | 93 ++++++++++++++++++++++++++++++++----------
>>  1 file changed, 72 insertions(+), 21 deletions(-)
>>