From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936113AbcKNCwL (ORCPT ); Sun, 13 Nov 2016 21:52:11 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:47094 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934845AbcKNCY7 (ORCPT ); Sun, 13 Nov 2016 21:24:59 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Dave@decadent.org.uk, "Peter Wu" , "Ben Skeggs" , "Hans de Goede" Date: Mon, 14 Nov 2016 00:14:20 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 133/346] drm/nouveau/acpi: check for function 0x1B before using it In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.39-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Peter Wu commit cba97805cb69d5b1a1d3bb108872c73b5bf0e205 upstream. Do not unconditionally invoke function 0x1B without checking for its availability, it leads to an infinite loop on some firmware. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=104791 Fixes: 5addcf0a5f0fad ("nouveau: add runtime PM support (v0.9)") Reviewed-by: Hans de Goede Signed-off-by: Peter Wu Acked-by: Dave Airlie Signed-off-by: Ben Hutchings --- drivers/gpu/drm/nouveau/nouveau_acpi.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) --- a/drivers/gpu/drm/nouveau/nouveau_acpi.c +++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c @@ -45,6 +45,7 @@ static struct nouveau_dsm_priv { bool dsm_detected; bool optimus_detected; + bool optimus_flags_detected; acpi_handle dhandle; acpi_handle other_handle; acpi_handle rom_handle; @@ -213,7 +214,8 @@ static struct vga_switcheroo_handler nou }; static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out, - bool *has_mux, bool *has_opt) + bool *has_mux, bool *has_opt, + bool *has_opt_flags) { acpi_handle dhandle; bool supports_mux; @@ -238,6 +240,7 @@ static void nouveau_dsm_pci_probe(struct *dhandle_out = dhandle; *has_mux = supports_mux; *has_opt = !!optimus_funcs; + *has_opt_flags = optimus_funcs & (1 << NOUVEAU_DSM_OPTIMUS_FLAGS); if (optimus_funcs) { uint32_t result; @@ -258,6 +261,7 @@ static bool nouveau_dsm_detect(void) acpi_handle dhandle = NULL; bool has_mux = false; bool has_optimus = false; + bool has_optimus_flags = false; int vga_count = 0; bool guid_valid; bool ret = false; @@ -272,13 +276,15 @@ static bool nouveau_dsm_detect(void) while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) { vga_count++; - nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus); + nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus, + &has_optimus_flags); } while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_3D << 8, pdev)) != NULL) { vga_count++; - nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus); + nouveau_dsm_pci_probe(pdev, &dhandle, &has_mux, &has_optimus, + &has_optimus_flags); } /* find the optimus DSM or the old v1 DSM */ @@ -289,6 +295,7 @@ static bool nouveau_dsm_detect(void) printk(KERN_INFO "VGA switcheroo: detected Optimus DSM method %s handle\n", acpi_method_name); nouveau_dsm_priv.optimus_detected = true; + nouveau_dsm_priv.optimus_flags_detected = has_optimus_flags; ret = true; } else if (vga_count == 2 && has_mux && guid_valid) { nouveau_dsm_priv.dhandle = dhandle; @@ -332,8 +339,9 @@ void nouveau_switcheroo_optimus_dsm(void if (!nouveau_dsm_priv.optimus_detected) return; - nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FLAGS, - 0x3, &result); + if (nouveau_dsm_priv.optimus_flags_detected) + nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_FLAGS, + 0x3, &result); nouveau_optimus_dsm(nouveau_dsm_priv.dhandle, NOUVEAU_DSM_OPTIMUS_CAPS, NOUVEAU_DSM_OPTIMUS_SET_POWERDOWN, &result);