From patchwork Tue Feb 12 11:49:41 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10807795 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 38DF9184E for ; Tue, 12 Feb 2019 11:49:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 25F512AD74 for ; Tue, 12 Feb 2019 11:49:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 17E642AD7A; Tue, 12 Feb 2019 11:49:54 +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 C16D82AD74 for ; Tue, 12 Feb 2019 11:49:53 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 438726E031; Tue, 12 Feb 2019 11:49:53 +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 CFD3F6E031 for ; Tue, 12 Feb 2019 11:49:51 +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 15549043-1500050 for multiple; Tue, 12 Feb 2019 11:49:43 +0000 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Tue, 12 Feb 2019 11:49:41 +0000 Message-Id: <20190212114941.26181-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915: Detect potential i915_reset_trylock() lockups 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: , Cc: Mika Kuoppala Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Use lockdep to warn before we wait indefinitely in case we may be waiting indefinitely. Suggested-by: Mika Kuoppala References: 2caffbf11762 ("drm/i915: Revoke mmaps and prevent access to fence registers across reset") Signed-off-by: Chris Wilson Cc: Mika Kuoppala --- drivers/gpu/drm/i915/i915_reset.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c index c1b53533ada6..364c74d1d59b 100644 --- a/drivers/gpu/drm/i915/i915_reset.c +++ b/drivers/gpu/drm/i915/i915_reset.c @@ -1305,6 +1305,8 @@ int i915_reset_trylock(struct drm_i915_private *i915) struct i915_gpu_error *error = &i915->gpu_error; int srcu; + might_lock(&error->reset_backoff_srcu); + rcu_read_lock(); while (test_bit(I915_RESET_BACKOFF, &error->flags)) { rcu_read_unlock();