From patchwork Wed Nov 6 18:58:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liviu Dudau X-Patchwork-Id: 13865286 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 77D9ED59F68 for ; Wed, 6 Nov 2024 18:58:21 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EBE4D10E760; Wed, 6 Nov 2024 18:58:20 +0000 (UTC) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by gabe.freedesktop.org (Postfix) with ESMTP id DC21B10E760 for ; Wed, 6 Nov 2024 18:58:18 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 490F7497; Wed, 6 Nov 2024 10:58:48 -0800 (PST) Received: from e110455-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 067FE3F528; Wed, 6 Nov 2024 10:58:16 -0800 (PST) From: Liviu Dudau To: Boris Brezillon Cc: Liviu Dudau , Steven Price , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Jann Horn Subject: [PATCH v2] drm/panthor: Lock XArray when getting entries for the VM Date: Wed, 6 Nov 2024 18:58:06 +0000 Message-ID: <20241106185806.389089-1-liviu.dudau@arm.com> X-Mailer: git-send-email 2.47.0 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Similar to cac075706f29 ("drm/panthor: Fix race when converting group handle to group object") we need to use the XArray's internal locking when retrieving a vm pointer from there. v2: Removed part of the patch that was trying to protect fetching the heap pointer from XArray, as that operation is protected by the @pool->lock. Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block") Reported-by: Jann Horn Cc: Boris Brezillon Cc: Steven Price Signed-off-by: Liviu Dudau Reviewed-by: Boris Brezillon Reviewed-by: Steven Price --- drivers/gpu/drm/panthor/panthor_mmu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c index 8ca85526491e6..46b84a557d9cc 100644 --- a/drivers/gpu/drm/panthor/panthor_mmu.c +++ b/drivers/gpu/drm/panthor/panthor_mmu.c @@ -1580,7 +1580,9 @@ panthor_vm_pool_get_vm(struct panthor_vm_pool *pool, u32 handle) { struct panthor_vm *vm; + xa_lock(&pool->xa); vm = panthor_vm_get(xa_load(&pool->xa, handle)); + xa_unlock(&pool->xa); return vm; }