From nobody Mon Feb 9 13:02:08 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 C97013128D9 for ; Thu, 8 Jan 2026 18:24:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767896690; cv=none; b=ET05bV+SCs9NVZtG5X0TjrKLUij/PIVVaKqC1Y7rytj64Gtyx/r+vjnpWjqJ1Jgpha8/OOV0phj7jTJH2OqumNefczqCU7ed8LiICfld1YWIUO1I9h2tONUmBV9IOf4QROcM7jXVXkGij0ja0s/SR2KSbYcCfaQHMxvwajIfOsw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767896690; c=relaxed/simple; bh=oONndJ8NVOgwMcyFFG+DGljb+tYe+0Iw4qIuIUve/EI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NCBA/l65Okz0SrhX2nh2l3nEwHymxWH19bHBIYx3RVYm+PrHMmSIzY3XvrARr65eNQdFBLYIh1XXOzKeFmO/zCFO7EYXBAEu1oM6fiMDyK/VnNIf3CxQSQix/DwZ/WTp6Mk9jnIYYqYyHUCEMv8Zt3p8aQ66pr0GSbt1PirQ3jw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=fXxAsLWO; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="fXxAsLWO" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1767896687; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EdJTpB//vW+EpSpID0j5xfF5Qc+6bYBE0DsV+JlakTM=; b=fXxAsLWO3bhy3g9405vNAP9F5srjzYlguyXm0KxmdIg+r9prVm+x5BzRwawLztLCavlRSe gcSwdT56H+HjxcQhM0w9F+F5TAvySE5ssvvZM1gMgDUgOBjl3pgLOl7z45BWnR/UCuZnJk t1o0SKmUlXfGP1gp1xRZrhVZ4xDV9Rw= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-257-5OWADEZhNPK15ahOaubzug-1; Thu, 08 Jan 2026 13:24:41 -0500 X-MC-Unique: 5OWADEZhNPK15ahOaubzug-1 X-Mimecast-MFC-AGG-ID: 5OWADEZhNPK15ahOaubzug_1767896677 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 82A0C1956096; Thu, 8 Jan 2026 18:24:37 +0000 (UTC) Received: from p16v.luc.cera.cz (unknown [10.44.32.20]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 60B17180009E; Thu, 8 Jan 2026 18:24:30 +0000 (UTC) From: Ivan Vecera To: netdev@vger.kernel.org Cc: Vadim Fedorenko , Arkadiusz Kubalewski , Jiri Pirko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Prathosh Satish , Tony Nguyen , Przemek Kitszel , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Saeed Mahameed , Leon Romanovsky , Tariq Toukan , Mark Bloch , Jonathan Lemon , Richard Cochran , Alexander Lobakin , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, intel-wired-lan@lists.osuosl.org, linux-rdma@vger.kernel.org, Michal Schmidt , Petr Oros , Grzegorz Nitka Subject: [PATCH net-next 09/12] dpll: Prevent duplicate registrations Date: Thu, 8 Jan 2026 19:23:15 +0100 Message-ID: <20260108182318.20935-10-ivecera@redhat.com> In-Reply-To: <20260108182318.20935-1-ivecera@redhat.com> References: <20260108182318.20935-1-ivecera@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Content-Type: text/plain; charset="utf-8" Modify the internal registration helpers dpll_xa_ref_{dpll,pin}_add() to reject duplicate registration attempts. Previously, if a caller attempted to register the same pin multiple times (with the same ops, priv, and cookie) on the same device, the core silently increments the reference count and return success. This behavior is incorrect because if the caller makes these duplicate registrations then for the first one dpll_pin_registration is allocated and for others the associated dpll_pin_ref.refcount is incremented. During the first unregistration the associated dpll_pin_registration is freed and for others WARN is fired. Fix this by updating the logic to return `-EEXIST` if a matching registration is found to enforce a strict "register once" policy. Signed-off-by: Ivan Vecera --- drivers/dpll/dpll_core.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c index c1cb9b4a376e7..bc7b75bcf9509 100644 --- a/drivers/dpll/dpll_core.c +++ b/drivers/dpll/dpll_core.c @@ -160,10 +160,8 @@ dpll_xa_ref_pin_add(struct xarray *xa_pins, struct dpl= l_pin *pin, if (ref->pin !=3D pin) continue; reg =3D dpll_pin_registration_find(ref, ops, priv, cookie); - if (reg) { - refcount_inc(&ref->refcount); - return 0; - } + if (reg) + return -EEXIST; ref_exists =3D true; break; } @@ -243,10 +241,8 @@ dpll_xa_ref_dpll_add(struct xarray *xa_dplls, struct d= pll_device *dpll, if (ref->dpll !=3D dpll) continue; reg =3D dpll_pin_registration_find(ref, ops, priv, cookie); - if (reg) { - refcount_inc(&ref->refcount); - return 0; - } + if (reg) + return -EEXIST; ref_exists =3D true; break; } --=20 2.52.0