From nobody Fri Jun 19 22:20:51 2026 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8E0AF2DECA3; Tue, 21 Apr 2026 17:52:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.81 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776793980; cv=none; b=genueSndbH0kWdiaZ2CllDWZqAHJYZJoHcuMTuDl01AXHXTzoo/hK6tWu6wvc3Hf8rOXYDJnxeTXavvENjnoIjBQ4FyXGL+eJAprMbjL1x2h1yv4ixYwWpyi6Gv926lzZgYMdAFJmtFwsVUw9IwgiqUOu1uDaL5CuxsDqfHlyNQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776793980; c=relaxed/simple; bh=vklTnXTtH2G3GzboPedzFr7jTeM/HFTCXqlHIaNUhB0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=UPzSzSSsYIpIXXLr1SmCMk5EgprhxOZ+bbMbT5oPGyb1C9IpToe+dTv2JQHlOvABDBxh5q2JwVl0yedL6dF8x4P2FNlvOi1YTTVu00mtfY8kv5S5B7ne+Hl+i/HOWE0Uvqiw+7RvlaEMYntiNj0lJd24AvaBsol11lRNYSFCHr8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from edelgard.fodlan.icenowy.me (unknown [112.94.102.10]) by APP-03 (Coremail) with SMTP id rQCowAC3vcReuedpblTLDg--.22569S2; Wed, 22 Apr 2026 01:52:32 +0800 (CST) From: Icenowy Zheng To: Frank Binns , Matt Coster , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: Brendan King , Danilo Krummrich , Donald Robson , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Icenowy Zheng , Icenowy Zheng , stable@vger.kernel.org Subject: [PATCH] pvr: acquire vm_ctx->lock before mapping memory to GPU VM Date: Wed, 22 Apr 2026 01:52:28 +0800 Message-ID: <20260421175228.1928742-1-zhengxingda@iscas.ac.cn> X-Mailer: git-send-email 2.52.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: rQCowAC3vcReuedpblTLDg--.22569S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Ww4kWw4Dury8Kw17tw1DWrg_yoW8Xry5pa 1fX3ySg3y8KrW0q3WUJ3Wj9ry3Zw4rua4xGFykX3Z3Zr1rJ3Wqyr1Fqry5XF90yFs7tr42 qrs0y343Xw12k3JanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9F14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVCY1x0267AKxVW8Jr 0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj 6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr 0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E 8cxan2IY04v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFV Cjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWl x4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r 1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_ JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcS sGvfC2KfnxnUUI43ZEXa7VUbGQ6JUUUUU== X-CM-SenderInfo: x2kh0wp0lqwv3d6l2u1dvotugofq/ Content-Type: text/plain; charset="utf-8" The drm gpuvm code doesn't protect find operation against map operation, and the driver needs to ensure a map operation shouldn't happen when a find operation is in progress. As all occurences of drm_gpuva_find*() is already guarded by vm_ctx->lock, make pvr_vm_map() to acquire this lock to prevent disturbing any find operation. This fixes occasional NULL deference in drm_gpuva_find*(). Cc: stable@vger.kernel.org Fixes: 4bc736f890ce ("drm/imagination: vm: make use of GPUVM's drm_exec hel= per") Signed-off-by: Icenowy Zheng --- drivers/gpu/drm/imagination/pvr_vm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/imagination/pvr_vm.c b/drivers/gpu/drm/imagina= tion/pvr_vm.c index e1ec60f34b6e6..eea88e7ad03c1 100644 --- a/drivers/gpu/drm/imagination/pvr_vm.c +++ b/drivers/gpu/drm/imagination/pvr_vm.c @@ -747,6 +747,7 @@ pvr_vm_map(struct pvr_vm_context *vm_ctx, struct pvr_ge= m_object *pvr_obj, =20 pvr_gem_object_get(pvr_obj); =20 + mutex_lock(&vm_ctx->lock); err =3D drm_gpuvm_exec_lock(&vm_exec); if (err) goto err_cleanup; @@ -754,9 +755,11 @@ pvr_vm_map(struct pvr_vm_context *vm_ctx, struct pvr_g= em_object *pvr_obj, err =3D pvr_vm_bind_op_exec(&bind_op); =20 drm_gpuvm_exec_unlock(&vm_exec); + mutex_unlock(&vm_ctx->lock); =20 err_cleanup: pvr_vm_bind_op_fini(&bind_op); + mutex_unlock(&vm_ctx->lock); =20 return err; } --=20 2.52.0