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 643E3FF4943 for ; Mon, 30 Mar 2026 05:30:38 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 044CE10E42E; Mon, 30 Mar 2026 05:30:37 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="FH+K+Md+"; dkim-atps=neutral Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0839A10E42B for ; Mon, 30 Mar 2026 05:30:36 +0000 (UTC) Received: by mail-ed1-f44.google.com with SMTP id 4fb4d7f45d1cf-6634bb959a2so4720087a12.1 for ; Sun, 29 Mar 2026 22:30:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1774848634; x=1775453434; darn=lists.freedesktop.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=rzyOkW6psCI+1rNPxWyjW/PJoO9NXtwwLlsKbLLkl+8=; b=FH+K+Md+QQnL4XlTnQ7HLl4ryVH7zKR71FvJl4XqrngL6j+DYRRwOkbRYNaVOx7lGZ eEHBNCQvhfTCsAP0Dw5aMTee/y3Lx3tNOLqLTAXei6Rd7qX18LVzlgTqPyc8d/Cym0xy aJDNs7qU3rX7F1Wp+8DkPQTIc9GLor7lkTcG8vzGL38pBJayQlKbcfsRO1t+KCoicDMp xWOi6zcD/yGDrCMldCBWtugKUC8x8a0gNIgUE2qG9hkZZ7Aai0ffah8+EZXw6G8tuFyQ hxn2+TsEwbSkT7yeQFDQKvS+NHAYAVUUwmwL1Fa5q2Fa8niXTQ+JhbpglB6sXNeTdS/s vszg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774848634; x=1775453434; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=rzyOkW6psCI+1rNPxWyjW/PJoO9NXtwwLlsKbLLkl+8=; b=CdMEaEI4p0ic85Ry3r3XGUEVCtk78QVmfRhdFz9Ddl5pEG/NOPAVKUw1MekTuxIcFQ WUMiiHlCjA2Q4wzj+jdsQIAnHbytm0Fx8Mim86mgAfnzHoWYifb9uFUZMFpSNj+ffBu1 tMp34yD58H94eKZyVzt21LAF+R3OkTfESlsN6C7dt1ltf0YSEebp52E7NmKKsffPjm/s JWb1rLcWNw4lNOVJtiIzShgdkT6cDNJPN+UMjACJIj7g8ZmXYz4c4nGDd6nMbnQLj9Ht JHdEkC3JYf/GCY1U3kdWjyuDkD7Wn0ieCZKO3Oi4pvXu9G+fJVAPdZxasnR7LQ00VkKu XgTA== X-Forwarded-Encrypted: i=1; AJvYcCUDhTmy1ODOdKyBlmtCdLYC3zsi8u6jVB8cAgCW3Ue3ZlqCsKVyHXl6I2PYxjNTHRCjURDRi4XdLX4=@lists.freedesktop.org X-Gm-Message-State: AOJu0YwROSfV0D7O0ssCSTgcZ+ZoznM9zpGAGzVv4q5l2XT4Vynhw3rH blaXYc9PmVc13yLdaWZ68lEEq0JLQdvLwBfHrOPFttRUAF7Q6mKKbmSy X-Gm-Gg: ATEYQzyZm5QZ13ftR6czBGrdxULsmuW+c2/s5cwnzu83sm5nYaglI9CSEjXmJdZUGYJ PIZ11pCbDX73l9PTttdOh94v3RrqBRNF3ReWpLIwwVoFotyvRw1W1fYbKQYsU1MUXCQ/sq7NWzf S+NSaI1YvkmzQAE5Ovf5/qnBaLyS7kRK/CjI1+2mojyE/g+YaCcMD2Ik+IJPoYYM0Kbi9kA/Ut4 IjN/wHZf5t84NHNOA99QgYM2RWwEaHkQXtJv53jro4Ja00RdnXDQrfg/UmnEr9ztXZMXaCSBD2a EVuXTw7dPplkBKt0GDKZrSLbomTBCM49NmB5LpTMrysHqx1Q+mPdcyH8/lQ5s/zWfscx/LZwVzv GNQV8rAHG4ZV7FZbbwuDkkLOdTNlIvL5kYhPG6uxC3/Eown5+/qJqETR12GyQVpqZfHzSxbUzVP mWLZKKGtO6wgNnnTQXZNgnWeOjl+tkTQl8LLdafo+zqkc= X-Received: by 2002:a17:906:b39e:b0:b98:3e7a:22c2 with SMTP id a640c23a62f3a-b9b5090a9admr504129566b.31.1774848633956; Sun, 29 Mar 2026 22:30:33 -0700 (PDT) Received: from localhost ([178.214.243.78]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b9b7b1a5fc9sm240417066b.36.2026.03.29.22.30.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 29 Mar 2026 22:30:32 -0700 (PDT) From: Mikhail Gavrilov To: Alex Deucher , =?UTF-8?q?Christian=20K=C3=B6nig?= Cc: Eric Huang , David Airlie , Simona Vetter , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, stable@vger.kernel.org, Mikhail Gavrilov Subject: [PATCH v2 0/2] drm/amdgpu: fix locking issues in PASID IDR management Date: Mon, 30 Mar 2026 10:30:23 +0500 Message-ID: <20260330053025.19203-1-mikhail.v.gavrilov@gmail.com> X-Mailer: git-send-email 2.53.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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" Commit 8f1de51f49be ("drm/amdgpu: prevent immediate PASID reuse case") converted the global PASID allocator from IDA to IDR with a spinlock for cyclic allocation. This introduced two locking bugs: 1) idr_alloc_cyclic() is called with GFP_KERNEL under spin_lock(), which can sleep. 2) amdgpu_pasid_free() can be called from hardirq context via the fence signal path (amdgpu_pasid_free_cb), but the lock is taken with plain spin_lock() in process context, creating a potential deadlock: CPU0 ---- spin_lock(&amdgpu_pasid_idr_lock) // process context, IRQs on spin_lock(&amdgpu_pasid_idr_lock) // deadlock The hardirq call chain is: sdma_v6_0_process_trap_irq -> amdgpu_fence_process -> dma_fence_signal -> drm_sched_job_done -> dma_fence_signal -> amdgpu_pasid_free_cb -> amdgpu_pasid_free This was observed on an RX 7900 XTX when exiting a Vulkan game running under Proton/Wine, which triggers the fence callback path during VM teardown. Patch 1 fixes the sleeping-under-spinlock by using idr_preload() with GFP_KERNEL before taking the lock, then GFP_NOWAIT for the actual allocation. Patch 2 converts all three spin_lock/spin_unlock call sites to spin_lock_irqsave/spin_unlock_irqrestore. Tested on ASUS ROG STRIX B650E-I / Ryzen 9 7950X / RX 7900 XTX with CONFIG_PROVE_LOCKING=y. The lockdep warning is no longer triggered after applying both patches. Mikhail Gavrilov (2): drm/amdgpu: fix sleeping allocation under spinlock in PASID IDR drm/amdgpu: use spin_lock_irqsave for PASID IDR lock drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) -- 2.53.0