On Wed, 24 Jun 2026 at 02:11, Long Li <[email protected]> wrote: > > The EAL hotplug multi-process messaging uses a fixed-size buffer > (EAL_DEV_MP_DEV_ARGS_MAX_LEN, 128 bytes) for device arguments. > When devargs exceeds this limit, strlcpy silently truncates the > string. This causes secondary processes to receive incomplete > devargs during hotplug re-add, leading to failed port > re-initialization. > > For example, a MANA PCI device with 6 mac= arguments: > > mac=AA:BB:CC:DD:EE:01,mac=AA:BB:CC:DD:EE:02, > mac=AA:BB:CC:DD:EE:03,mac=AA:BB:CC:DD:EE:04, > mac=AA:BB:CC:DD:EE:05,mac=AA:BB:CC:DD:EE:06 > > produces a 131-byte devargs string that gets silently truncated > to 127 bytes, losing the last MAC address. > > Return -E2BIG from rte_dev_probe() when devargs would be truncated, > instead of silently corrupting data. rte_dev_remove() does not need > the same check because the length was already validated at probe time. > > Fixes: 244d5130719c ("eal: enable hotplug on multi-process") > Cc: [email protected] > > Signed-off-by: Long Li <[email protected]>
Re-reading the function, I have one concern about the fix. I agree there is a bug with multiprocess. But this change here also imposes a limit to 128 that was not there before, even if multiprocess is disabled. It may not be a big problem, but we are calling the the multi process machinerie when unneeded (it ends up with a ENOTSUP). I sent a small patch on this topic, could you have a look please? https://inbox.dpdk.org/dev/[email protected]/ -- David Marchand
