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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 03BD6FD88C5 for ; Tue, 10 Mar 2026 22:50:50 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BE5D410E797; Tue, 10 Mar 2026 22:50:49 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="WHMLS4gE"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9789410E791 for ; Tue, 10 Mar 2026 22:50:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1773183044; x=1804719044; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=1PYGlGe6o5enDEtJxv7ZITtMqjuaLLBnX78P1ipbvd0=; b=WHMLS4gEoOPaaFLZzyAHj2Kt16DeYwm+qVAN59GwcBZUktMj7Ilwaita Ep44OeRGB45MZnubzotv67vAeHE1jUl+7h+Nxg5MCF1LjppnB3tzs6Gax 7aA1dW4vj15njcdNzuTk985QWgPDnTjnocZaSKEjlYI6GlwxRSDFzZG0j 4HyJZs1Aeltt/nFkY/C+f1TQzX/2d1zMz6pCkZ3Byb13HISrwXolWtdt6 WbMohOYsS/ZR1Ojt5JJU258TJvKRGXCxsyPAHCOqW1JIBm1aMyqdpHFEV GnRBdN8IQe32MtrQnRKtLqni5Kn81wD+wLFcPZ0W9q26YZ2B4Po76OkZ+ A==; X-CSE-ConnectionGUID: DEDOT+L0TLy8mgSpk6rRpQ== X-CSE-MsgGUID: 5Qmv1cF4TzCQbFc8koK1TQ== X-IronPort-AV: E=McAfee;i="6800,10657,11725"; a="61817890" X-IronPort-AV: E=Sophos;i="6.23,113,1770624000"; d="scan'208";a="61817890" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2026 15:50:43 -0700 X-CSE-ConnectionGUID: Py+mOid8QH6kgLJOqe57Cw== X-CSE-MsgGUID: 5cnMJ7znSyGSXv39ZbjeSg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,113,1770624000"; d="scan'208";a="220441009" Received: from guc-pnp-dev-box-1.fm.intel.com ([10.1.39.24]) by orviesa007.jf.intel.com with ESMTP; 10 Mar 2026 15:50:42 -0700 From: Zhanjun Dong To: intel-xe@lists.freedesktop.org Cc: Matthew Brost , stable@vger.kernel.org, Zhanjun Dong Subject: [PATCH v9 7/7] drm/xe: Open-code GGTT MMIO access protection Date: Tue, 10 Mar 2026 18:50:39 -0400 Message-Id: <20260310225039.1320161-8-zhanjun.dong@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260310225039.1320161-1-zhanjun.dong@intel.com> References: <20260310225039.1320161-1-zhanjun.dong@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" From: Matthew Brost GGTT MMIO access is currently protected by hotplug (drm_dev_enter), which works correctly when the driver loads successfully and is later unbound or unloaded. However, if driver load fails, this protection is insufficient because drm_dev_unplug() is never called. Additionally, devm release functions cannot guarantee that all BOs with GGTT mappings are destroyed before the GGTT MMIO region is removed, as some BOs may be freed asynchronously by worker threads. To address this, introduce an open-coded flag, protected by the GGTT lock, that guards GGTT MMIO access. The flag is cleared during the dev_fini_ggtt devm release function to ensure MMIO access is disabled once teardown begins. Cc: stable@vger.kernel.org Fixes: 919bb54e989c ("drm/xe: Fix missing runtime outer protection for ggtt_remove_node") Signed-off-by: Matthew Brost Reviewed-by: Zhanjun Dong --- drivers/gpu/drm/xe/xe_ggtt.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_ggtt.c b/drivers/gpu/drm/xe/xe_ggtt.c index 0f2e3af49912..21071b64b09d 100644 --- a/drivers/gpu/drm/xe/xe_ggtt.c +++ b/drivers/gpu/drm/xe/xe_ggtt.c @@ -66,6 +66,9 @@ * give us the correct placement for free. */ +#define XE_GGTT_FLAGS_64K BIT(0) +#define XE_GGTT_FLAGS_ONLINE BIT(1) + /** * struct xe_ggtt_node - A node in GGTT. * @@ -117,6 +120,8 @@ struct xe_ggtt { * @flags: Flags for this GGTT * Acceptable flags: * - %XE_GGTT_FLAGS_64K - if PTE size is 64K. Otherwise, regular is 4K. + * - %XE_GGTT_FLAGS_ONLINE - is GGTT online, protected by ggtt->lock + * after init */ unsigned int flags; /** @scratch: Internal object allocation used as a scratch page */ @@ -367,6 +372,8 @@ static void dev_fini_ggtt(void *arg) { struct xe_ggtt *ggtt = arg; + scoped_guard(mutex, &ggtt->lock) + ggtt->flags &= ~XE_GGTT_FLAGS_ONLINE; drain_workqueue(ggtt->wq); } @@ -437,6 +444,7 @@ int xe_ggtt_init_early(struct xe_ggtt *ggtt) if (err) return err; + ggtt->flags |= XE_GGTT_FLAGS_ONLINE; return devm_add_action_or_reset(xe->drm.dev, dev_fini_ggtt, ggtt); } ALLOW_ERROR_INJECTION(xe_ggtt_init_early, ERRNO); /* See xe_pci_probe() */ @@ -465,13 +473,10 @@ static void ggtt_node_fini(struct xe_ggtt_node *node) static void ggtt_node_remove(struct xe_ggtt_node *node) { struct xe_ggtt *ggtt = node->ggtt; - struct xe_device *xe = tile_to_xe(ggtt->tile); bool bound; - int idx; - - bound = drm_dev_enter(&xe->drm, &idx); mutex_lock(&ggtt->lock); + bound = ggtt->flags & XE_GGTT_FLAGS_ONLINE; if (bound) xe_ggtt_clear(ggtt, xe_ggtt_node_addr(node), xe_ggtt_node_size(node)); drm_mm_remove_node(&node->base); @@ -484,8 +489,6 @@ static void ggtt_node_remove(struct xe_ggtt_node *node) if (node->invalidate_on_remove) xe_ggtt_invalidate(ggtt); - drm_dev_exit(idx); - free_node: ggtt_node_fini(node); } -- 2.34.1