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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: UWbBRD8dkMEuZV3KQrE8uhvpqbagp6/tc7nV7WjV1eG5D5ZGsQboxP6YajsX4qZC/HI+UsWk/ENHVnQSNnyyVsZnq7qkyIA3UhbtmB/uzyAQ8zTSd13QwIY4nHcLpcDxgPN2JrNlPGewidvGIf02iJ3dNB+wyNG3z7/MO1huhzU5qHqklc+JDKlJ6aatkqGXCwSbpM4nYK37FVALnxQGuvcX+KYeFhpTTTd8CFVV6tAE8WjNwdD2p5CXvHzhxsDUH9pnRFKkYY3Ls4FPiRTUheiCAArYvnOo6byMgsi/VoWOGrlIbvL9Z/1a8o0UXwX/R2imcAO3KskX8DV7WiX9UpFFcA9tkphAiiEVS4GGeHCG1wLfic5gNBjuTWpK+tMhdxeYcIZNsaeDBPAY2eeF/kdIJmiJW0ikj4lEuDwL8EKdfhglA1zniiZk0Ve2V4pQ X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Jun 2026 22:28:14.8299 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 9a0f0a98-a2d3-4774-b514-08dec28891b3 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ5PEPF000001EA.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4318 On 6/2/2026 3:34 AM, Arnaud POULIQUEN wrote: > > > On 5/29/26 18:43, Tanmay Shah wrote: >> RPMsg MTU size can be variable now and no longer hardcoded to 512 bytes. >> Add log to the sample driver that prints current MTU size of the rpmsg >> buffer. >> >> Signed-off-by: Tanmay Shah >> --- >> >> Changes in v3: >>    - Check for error when retrieving MTU size >>    - %s/mtu/MTU/ >> >>   samples/rpmsg/rpmsg_client_sample.c | 9 +++++++++ >>   1 file changed, 9 insertions(+) >> >> diff --git a/samples/rpmsg/rpmsg_client_sample.c b/samples/rpmsg/ >> rpmsg_client_sample.c >> index ae5081662283..55afa53189af 100644 >> --- a/samples/rpmsg/rpmsg_client_sample.c >> +++ b/samples/rpmsg/rpmsg_client_sample.c >> @@ -52,6 +52,7 @@ static int rpmsg_sample_probe(struct rpmsg_device >> *rpdev) >>   { >>       int ret; >>       struct instance_data *idata; >> +    ssize_t mtu; >>         dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n", >>                       rpdev->src, rpdev->dst); >> @@ -62,6 +63,14 @@ static int rpmsg_sample_probe(struct rpmsg_device >> *rpdev) >>         dev_set_drvdata(&rpdev->dev, idata); >>   +    mtu = rpmsg_get_mtu(rpdev->ept); >> +    if (mtu < 0) { >> +        dev_warn(&rpdev->dev, "invalid rpmsg MTU size = %ld\n", mtu); >> +        return mtu; >> +    } >> + >> +    dev_info(&rpdev->dev, "rpmsg MTU size = %ld\n", mtu); >> + > > Do you really need this commit? rpmsg_send should return an error if the > buffer size is insufficient [1]. > > [1] https://elixir.bootlin.com/linux/v7.0.10/source/drivers/rpmsg/ > virtio_rpmsg_bus.c#L517 > Here, I just want to demonstrate rpmsg_get_mtu() API. Now we can have a configurable size of the RPMsg buffer. So rpmsg_get_mtu() API can be used to check correct buffer length before even using rpmsg_send() API. I think I should check msg length against mtu size as well. > Regards, > Arnaud > >>       /* send a message to our remote processor */ >>       ret = rpmsg_send(rpdev->ept, MSG, strlen(MSG)); >>       if (ret) { >