From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F41FD2F28FF; Wed, 16 Sep 2026 13:15:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789564561; cv=none; b=ncajiQI0H+tHeFaYmbui4Oik0/2w/nwbEiNGaJ6myL9AmRDl9sSWP3SIJxkTcA9xlchC0oDCYruZ0SR9LZu9PFVgvQTDDZv4VWMu5N1S3/k5W++XLgjkciBhgkwYDdo4qdpoJyZabL+SFYNqTljGsXwmNMlZ7dX3/dp+fwxlEuM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789564561; c=relaxed/simple; bh=Lc0rLf19IsM8R3K7ZLPMFRu3XLASZ4jE6WD+1eHBW0Q=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=kJ1FOtZeh8q8tz0a+Czp+R2HOnkRQpecprDAsQxXCBcBYyGfug+R3eZpYgPb0cQHSzUKLqSMmhHo9jYWBbvPljMskfPWIKAwFNJqFEqYZzbuiac33n0z/HFwj5qu9tJceHWPb854kx7rSXKdcNK+rgBgm93DmuHPVvg1DuNvlfY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XUMMVdu1; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="XUMMVdu1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28D9B1F00898; Wed, 16 Sep 2026 13:15:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789564559; bh=xYDFsT51uAGXAOJoe1gXsDtdZ1wy1F5AbNcqAArzh9E=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=XUMMVdu15dqYZ94O34/bjyFuaFLXRMNJrVCSkxJ3g7VKH533a5gwxtOi3v+42f1/n 9NPyHPEpSriyglFKJV2914L5qpdqUQRIbhzwckevVbolqJD3uF4G2ivawST8+fbBVX JQyAaj6wpEotWHB70FeO6R64aEy5OjO2G7tA7ZmQf8uSK6tV/41/jz049WMlnGnJ1l xkHVX9P2SlzmA5klyYBCkOOtmxL7qNTsqG+Vie+KMNOPrGyr2GJwRHFcDZ1uextpRL GdGgM0QXjBaPm2BlUrDtw0kzGpgqPLp1jXsg78ziyJcv5q/O6GKNiWIsuKB1IfRlqh bqiyUtkZyZHPA== From: sashiko-bot@kernel.org Subject: Re: [PATCH net v2 2/5] vsock/virtio: Streamline socket reset on transport/PM event Reply-To: sashiko-reviews@lists.linux.dev To: "Michal Luczaj" Cc: "Michael S. Tsirkin" , virtualization@lists.linux.dev, "Eugenio Perez" , kvm@vger.kernel.org In-Reply-To: <20260915-vsock-connect-reset-closing-v2-2-a1d9abb472f7@rbox.co> References: <20260915-vsock-connect-reset-closing-v2-0-a1d9abb472f7@rbox.co> <20260915-vsock-connect-reset-closing-v2-2-a1d9abb472f7@rbox.co> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 16 Sep 2026 13:15:58 +0000 Message-Id: <20260916131559.28D9B1F00898@smtp.kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [Medium] vsock: lost peer_shutdown update in lockless reset -- commit c52d0f36e0857217fee2a98454aaab9edf069cc3 Author: Michal Luczaj vsock/virtio: Streamline socket reset on transport/PM event This commit streamlines socket resets on transport or power management events by setting SHUTDOWN_MASK in virtio_vsock_reset_sock(). It aligns the virtio transport with similar behavior in vhost and VMCI. > diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_tran= sport.c > --- a/net/vmw_vsock/virtio_transport.c > +++ b/net/vmw_vsock/virtio_transport.c [ ... ] > static void virtio_vsock_reset_sock(struct sock *sk) > { > + struct vsock_sock *vsk =3D vsock_sk(sk); > + > /* vmci_transport.c doesn't take sk_lock here either. At least we're > * under vsock_table_lock so the sock cannot disappear while we're > * executing. > */ > =20 > + vsk->peer_shutdown =3D SHUTDOWN_MASK; [Severity: Medium] Could this lockless assignment race with the lock-protected read-modify-wri= te in the RX path? Looking at virtio_transport_recv_connected(), it processes VIRTIO_VSOCK_OP_SHUTDOWN while holding sk_lock. It reads vsk->peer_shutdown via READ_ONCE(), applies a bitwise OR (such as peer_shutdown |=3D RCV_SHUTD= OWN), and writes it back with WRITE_ONCE(). If the lockless assignment here occurs between the RX thread's read and write, could the RX thread overwrite SHUTDOWN_MASK with its local value, dropping the SEND_SHUTDOWN state? If this lost update occurs, it seems the socket would lose its full shutdown state. Would this cause vsock_poll() to miss setting EPOLLHUP and EPOLLRDHUP flags, breaking API expectations? Additionally, might this plain write trigger KCSAN data race warnings again= st concurrent READ_ONCE() calls? > sk->sk_state =3D TCP_CLOSE; > sk->sk_err =3D ECONNRESET; > sk_error_report(sk); > } --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260915-vsock-conn= ect-reset-closing-v2-0-a1d9abb472f7@rbox.co?part=3D2