From patchwork Fri Dec 7 11:05:54 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10717959 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0E98315A6 for ; Fri, 7 Dec 2018 11:06:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EA7022E600 for ; Fri, 7 Dec 2018 11:06:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DEEBC2E688; Fri, 7 Dec 2018 11:06:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CDA602E600 for ; Fri, 7 Dec 2018 11:06:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C604D6E6DF; Fri, 7 Dec 2018 11:06:09 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 189D96E6DF for ; Fri, 7 Dec 2018 11:06:07 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 14814191-1500050 for multiple; Fri, 07 Dec 2018 11:05:56 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Fri, 7 Dec 2018 11:05:54 +0000 Message-Id: <20181207110554.19897-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.0.rc2 In-Reply-To: <20181207091640.709-1-chris@chris-wilson.co.uk> References: <20181207091640.709-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v3] drm/i915: Skip the ERR_PTR error state X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Although commit fb6f0b64e455 ("drm/i915: Prevent machine hang from Broxton's vtd w/a and error capture") applied cleanly after a 24 month hiatus, the code had moved on with new methods for peeking and fetching the captured gpu info. Make sure we catch all uses of the stashed error state and avoid dereferencing the error pointer. v2: Move error pointer determination into i915_gpu_capture_state v3: Restore early check to avoid capturing and then throwing away subsequent GPU error states. Fixes: fb6f0b64e455 ("drm/i915: Prevent machine hang from Broxton's vtd w/a and error capture") Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Joonas Lahtinen Reviewed-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/i915_debugfs.c | 12 +++++++++--- drivers/gpu/drm/i915/i915_gpu_error.c | 23 ++++++++++++++--------- drivers/gpu/drm/i915/i915_sysfs.c | 4 +++- 3 files changed, 26 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 38dcee1ca062..40a61ef9aac1 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -984,8 +984,8 @@ static int i915_gpu_info_open(struct inode *inode, struct file *file) intel_runtime_pm_get(i915); gpu = i915_capture_gpu_state(i915); intel_runtime_pm_put(i915); - if (!gpu) - return -ENOMEM; + if (IS_ERR(gpu)) + return PTR_ERR(gpu); file->private_data = gpu; return 0; @@ -1018,7 +1018,13 @@ i915_error_state_write(struct file *filp, static int i915_error_state_open(struct inode *inode, struct file *file) { - file->private_data = i915_first_error_state(inode->i_private); + struct i915_gpu_state *error; + + error = i915_first_error_state(inode->i_private); + if (IS_ERR(error)) + return PTR_ERR(error); + + file->private_data = error; return 0; } diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index 07465123c166..3f9ce403c755 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -1907,9 +1907,16 @@ i915_capture_gpu_state(struct drm_i915_private *i915) { struct i915_gpu_state *error; + /* Check if GPU capture has been disabled */ + error = READ_ONCE(i915->gpu_error.first_error); + if (IS_ERR(error)) + return error; + error = kzalloc(sizeof(*error), GFP_ATOMIC); - if (!error) - return NULL; + if (!error) { + i915_disable_error_state(i915, -ENOMEM); + return ERR_PTR(-ENOMEM); + } kref_init(&error->ref); error->i915 = i915; @@ -1945,11 +1952,8 @@ void i915_capture_error_state(struct drm_i915_private *i915, return; error = i915_capture_gpu_state(i915); - if (!error) { - DRM_DEBUG_DRIVER("out of memory, not capturing error state\n"); - i915_disable_error_state(i915, -ENOMEM); + if (IS_ERR(error)) return; - } i915_error_capture_msg(i915, error, engine_mask, error_msg); DRM_INFO("%s\n", error->error_msg); @@ -1987,7 +1991,7 @@ i915_first_error_state(struct drm_i915_private *i915) spin_lock_irq(&i915->gpu_error.lock); error = i915->gpu_error.first_error; - if (error) + if (!IS_ERR_OR_NULL(error)) i915_gpu_state_get(error); spin_unlock_irq(&i915->gpu_error.lock); @@ -2000,10 +2004,11 @@ void i915_reset_error_state(struct drm_i915_private *i915) spin_lock_irq(&i915->gpu_error.lock); error = i915->gpu_error.first_error; - i915->gpu_error.first_error = NULL; + if (error != ERR_PTR(-ENODEV)) /* if disabled, always disabled */ + i915->gpu_error.first_error = NULL; spin_unlock_irq(&i915->gpu_error.lock); - if (!IS_ERR(error)) + if (!IS_ERR_OR_NULL(error)) i915_gpu_state_put(error); } diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c index 535caebd9813..c0cfe7ae2ba5 100644 --- a/drivers/gpu/drm/i915/i915_sysfs.c +++ b/drivers/gpu/drm/i915/i915_sysfs.c @@ -521,7 +521,9 @@ static ssize_t error_state_read(struct file *filp, struct kobject *kobj, ssize_t ret; gpu = i915_first_error_state(i915); - if (gpu) { + if (IS_ERR(gpu)) { + ret = PTR_ERR(gpu); + } else if (gpu) { ret = i915_gpu_state_copy_to_buffer(gpu, buf, off, count); i915_gpu_state_put(gpu); } else {