On Thu, Sep 4, 2025 at 11:27 AM Stanislav Fomichev <[email protected]> wrote:
>
> devmem test fails on NIPA. Most likely we get skb(s) with readable
> frags (why?)
I would expect if we get readable frags that the frags land in the
host buffer we provide ncdevmem and we actually hit this error:
```
1 if (!is_devmem) {
0 pr_err("flow steering error");
1 goto err_close_client;
2 }
```
which as it says, should be root caused in a flow steering error. I
don't know what would cause an EFAULT off the top of my head.
> but the failure manifests as an OOM. The OOM happens
> because ncdevmem spams the following message:
>
> recvmsg ret=-1
> recvmsg: Bad address
>
> As of today, ncdevmem can't deal with various reasons of EFAULT:
> - falling back to regular recvmsg for non-devmem skbs
> - increasing ctrl_data size (can't happen with ncdevmem's large buffer)
>
> Exit (cleanly) with error when recvmsg returns EFAULT. This should at
> least cause the test to cleanup its state.
>
> Signed-off-by: Stanislav Fomichev <[email protected]>
Either way, change looks good to me.
Reviewed-by: Mina Almasry <[email protected]>
--
Thanks,
Mina
