Re: [PATCH net v1 1/3] net: core: propagate unreadable flag in skb_zerocopy

[Pavel Begunkov]

On 8/1/26 13:52, Mina Almasry wrote:
> When skb_zerocopy() copies devmem payload fragments, it fails to update
> the target skb's unreadable flag. This causes the target to appear as
> readable memory.
>
> Propagate the unreadable flag if any devmem fragments were copied from
> the source.

From a quick look, it doesn't seem like the function would work reliably
with netmems even with this patch, but that's a different kind of issue
we can return to later. Curious, did you hit this in prod?

Reviewed-by: Pavel Begunkov <asml.silence@xxxxxxxxx>

> Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags")
> Cc: Pavel Begunkov <asml.silence@xxxxxxxxx>
> Cc: Stanislav Fomichev <sdf@xxxxxxxxxxx>
> Cc: Bobby Eshleman <bobbyeshleman@xxxxxxxxx>
> Cc: Florian Westphal <fw@xxxxxxxxx>
> Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>
> ---
>   net/core/skbuff.c | 3 +++
>   1 file changed, 3 insertions(+)
--
Pavel Begunkov