From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE7C2C43381 for ; Mon, 1 Apr 2019 17:15:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82D0B2133D for ; Mon, 1 Apr 2019 17:15:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554138903; bh=bOEbv97eVOTyrs1zkuO2wC/rpdCpRtcq7MYShRl+ZG8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iDc56vfo9i808+GfoWYWRJEMCqUC7B84BdbB22RWTadh940GRJ/UMcmEi18baEPih MLCcXuLZzPvB9pB4txbsyynI5hMmKKFbQnfRH9iWCsyczAxpmqUi8fWI8foMRNyNqT E6LEYe5uE4LsgLcsHp1ZnOBkQXxxmmi12j/k14Sw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730610AbfDARPC (ORCPT ); Mon, 1 Apr 2019 13:15:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:38728 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730828AbfDARO7 (ORCPT ); Mon, 1 Apr 2019 13:14:59 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7035920856; Mon, 1 Apr 2019 17:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554138898; bh=bOEbv97eVOTyrs1zkuO2wC/rpdCpRtcq7MYShRl+ZG8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HRq+cqHwopQcC7oCKsto5wVTIK+gi9M4/pT7W0LMaZRgCRKb7EzyS/bXPpVU2aFku qSe3dmZRzVOKRK9QhoYJaanr+eJDwWQOvOkEZWPjZ69ThhLV0r0buhMZfxFCaXg1ln MUUr2yUzeBBPbd5DWuauXak0mMbcIjEbnHbHrpdU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Farman , Cornelia Huck Subject: [PATCH 4.19 053/134] vfio: ccw: only free cp on final interrupt Date: Mon, 1 Apr 2019 19:01:29 +0200 Message-Id: <20190401170049.495077280@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170044.243719205@linuxfoundation.org> References: <20190401170044.243719205@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cornelia Huck commit 50b7f1b7236bab08ebbbecf90521e84b068d7a17 upstream. When we get an interrupt for a channel program, it is not necessarily the final interrupt; for example, the issuing guest may request an intermediate interrupt by specifying the program-controlled-interrupt flag on a ccw. We must not switch the state to idle if the interrupt is not yet final; even more importantly, we must not free the translated channel program if the interrupt is not yet final, or the host can crash during cp rewind. Fixes: e5f84dbaea59 ("vfio: ccw: return I/O results asynchronously") Cc: stable@vger.kernel.org # v4.12+ Reviewed-by: Eric Farman Signed-off-by: Cornelia Huck Signed-off-by: Greg Kroah-Hartman --- drivers/s390/cio/vfio_ccw_drv.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/s390/cio/vfio_ccw_drv.c +++ b/drivers/s390/cio/vfio_ccw_drv.c @@ -72,20 +72,24 @@ static void vfio_ccw_sch_io_todo(struct { struct vfio_ccw_private *private; struct irb *irb; + bool is_final; private = container_of(work, struct vfio_ccw_private, io_work); irb = &private->irb; + is_final = !(scsw_actl(&irb->scsw) & + (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)); if (scsw_is_solicited(&irb->scsw)) { cp_update_scsw(&private->cp, &irb->scsw); - cp_free(&private->cp); + if (is_final) + cp_free(&private->cp); } memcpy(private->io_region->irb_area, irb, sizeof(*irb)); if (private->io_trigger) eventfd_signal(private->io_trigger, 1); - if (private->mdev) + if (private->mdev && is_final) private->state = VFIO_CCW_STATE_IDLE; }