Re: [PATCH net v2] hv_sock: Report EOF instead of -EIO for FIN

[Stefano Garzarella]

On Thu, Apr 16, 2026 at 12:14:33PM -0700, Dexuan Cui wrote:
> Commit f0c5827d07cb unluckily causes a regression for the FIN packet,
> and the final read syscall gets an error rather than 0.
>
> Ideally, we would want to fix hvs_channel_readable_payload() so that it
> could return 0 in the FIN scenario, but it's not good for the hv_sock
> driver to use the VMBus ringbuffer's cached priv_read_index, which is
> internal data in the VMBus driver.
>
> Fix the regression in hv_sock by returning 0 rather than -EIO.
>
> Fixes: f0c5827d07cb ("hv_sock: Return the readable bytes in hvs_stream_has_data()")
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: Ben Hillis <Ben.Hillis@xxxxxxxxxxxxx>
> Reported-by: Mitchell Levy <levymitchell0@xxxxxxxxx>
> Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
> ---
>
> Changes since v1:
>    Removed the local variable 'need_refill' to make the code more
>    readable. Stefano, thanks!

Thanks for the fix!

>    No other change.
>
> net/vmw_vsock/hyperv_transport.c | 20 ++++++++++++++++----
> 1 file changed, 16 insertions(+), 4 deletions(-)

Acked-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>