Re: [PATCH net-next v10 06/10] tap: Introduce virtio-net hash feature

From: Paolo Abeni
Date: Mon Mar 17 2025 - 04:35:11 EST


On 3/13/25 8:01 AM, Akihiko Odaki wrote:
> @@ -998,6 +1044,16 @@ static long tap_ioctl(struct file *file, unsigned int cmd,
> rtnl_unlock();
> return ret;
>
> + case TUNGETVNETHASHCAP:
> + return tun_vnet_ioctl_gethashcap(argp);
> +
> + case TUNSETVNETHASH:
> + rtnl_lock();
> + tap = rtnl_dereference(q->tap);
> + ret = tap ? tun_vnet_ioctl_sethash(&tap->vnet_hash, argp) : -EBADFD;


Not really a review, but apparently this is causing intermittent memory
leak in self tests:

xx__-> echo scan > /sys/kernel/debug/kmemleak && cat
/sys/kernel/debug/kmemleak
unreferenced object 0xffff88800c6ec248 (size 8):
comm "tap", pid 21124, jiffies 4299141559
hex dump (first 8 bytes):
00 00 00 00 00 00 00 00 ........
backtrace (crc 0):
__kmalloc_cache_noprof+0x2df/0x390
tun_vnet_ioctl_sethash+0xbf/0x3a0
tap_ioctl+0x6f2/0xc10
__x64_sys_ioctl+0x11f/0x180
do_syscall_64+0xc1/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Could you please have a look?

Thanks!

Paolo