shared memory application to run on non rootcell

[anila...@gmail.com]

Jan,
we are tying to access( read & write) from shared memory region between root cell and non rootcell. I cant use ivshm-shared.bin file because I want to load another linux kernel on non rootcell. After booting into non rootcell, how can I write into shared memory region and trigger interrupt so that root cell can receive it. I am using minimal file system in non rootcell and I cant compile and create some application on non rootcell.
Can I create ivshm-shared memory application instead of binary in rootcell. If yes, I can use this application to run on non rootcell to write into share memory region.
please suggest me is there any way to achieve this.
Regards,
Anil

[Jan Kiszka]

Have a look at Documentation/inter-cell-communication.txt and
specifically also https://github.com/henning-schild-work/ivshmem-guest-code.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux

[a.k...@matellio.com]

Hi,

we followed the steps as mentioned in the below two files.
https://github.com/henning-schild-work/ivshmem-guest-code
Documentation/inter-cell-communication.txt

We are running QEMU in X86_64 laptop.

scenario-1:
----------
able to enable root-cell for shared memory.
loaded ivshmem-demo.bin application for non-root-cell successfully.
interrupts are been sent from demo apps and able to receive "hello from ivshmem " when we run shmem_test.py.
I assume after we receive above "hello ..." message , communication is established and shared memory is tested successfully. Please clarify my assumption or understanding.
ivshmem-demo.c is from the jailhouse tree and we did not do any modification.

scenario-2
------------
tried to communicate between root-cell and non-root-cell linux using shared memory.
followed all steps for enabling root-cell and then non-root-cell-linux.
we tried to verify whether shared memory is present is not using uio_send / uio_read.
parameters given to uio_send is below:
uio_send /dev/uio0 3 3 /dev/uio0
parameters given to uio_read is below:
uio_read /dev/uio0 3

I afraid whether the above parameters given is correct or am i missing some detail.

attached root-cell-linux and non-root-cell-linux config file for reference.
also attached log file(non-root-cell-linux-log.txt) of non-root-cell-linux when booting.

kindly help here as we tried in all ways to establish root-cell-linux <--> non-root-cell-linux shared memory communication, but could not succeed.