From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout06.his.huawei.com (canpmsgout06.his.huawei.com [113.46.200.221]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A8C149A3AB; Fri, 18 Sep 2026 08:43:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.221 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789721006; cv=none; b=cRIIKps21M0V4BEgxmhRVm9Bi5gPcadWcUKtxwoePRZhWV4DE1dRLB6my1RYE3+q6NpsCBY8sYMM9BpVOHZrdlyNTJQCfcmYg9j40oyHcbFLBwZ9EVS7p1/K+YCwtJ0DQGILMzH+XLSo5NdgPXP34u1fn6qB7StIy9H4+iTxOtY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789721006; c=relaxed/simple; bh=EY8K/VzeOI3yuxlBnPBiEIl1h5qybRiUtB8bGEOUjaA=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=KZOcgAkp6ZT3fcUpPFm8BkoEIJnlTam8D6Y1ayTxMMYpFb1n3nDB+f88m4UBvBoMGuaNTRxHnkOhYQHdlgEGvd7vk50zmY1IDuPYVGpmOvtQ4+vLCxKkUeZETAHabgoanlH2JB2iKO7I36SVwS6sqg2OFZvPw/buVYcecE89g7Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=KYpuxGPW; arc=none smtp.client-ip=113.46.200.221 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="KYpuxGPW" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=foFuPJGFKDj9ITO6MPchpecWpxif5LDmm96lzrsIlUk=; b=KYpuxGPWPDfqI8xEunzxseA1IFG1YGy8aHOf1ghHOn83hRV9fQKxCxhjBfEqHEld2vKENXZDH 7LsCjVyB+eWRhD19Xko1GR/X0+1QNiQIfpGr33YPpaxMm7snuXI5nk1k6z7YHnWjGTbeVMok59y 8Esoh+DVR4Pa2DBH8RNRvFk= Received: from mail.maildlp.com (unknown [172.19.162.144]) by canpmsgout06.his.huawei.com (SkyGuard) with ESMTPS id 4hmQpq6j8rzRhQs; Fri, 18 Sep 2026 16:32:19 +0800 (CST) Received: from whupemk100014.china.huawei.com (unknown [7.152.184.20]) by mail.maildlp.com (Postfix) with ESMTPS id 52BDF4056D; Fri, 18 Sep 2026 16:43:17 +0800 (CST) Received: from huawei.com (10.50.163.32) by whupemk100014.china.huawei.com (7.152.184.20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.45; Fri, 18 Sep 2026 16:43:16 +0800 From: Longfang Liu To: , CC: , , Subject: [PATCH v4 1/2] hisi_acc_vfio_pci: fix NULL dereference in reset_prepare on PF passthrough Date: Fri, 18 Sep 2026 16:42:43 +0800 Message-ID: <20260918084244.1485837-2-liulongfang@huawei.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260918084244.1485837-1-liulongfang@huawei.com> References: <20260918084244.1485837-1-liulongfang@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To whupemk100014.china.huawei.com (7.152.184.20) When a PF is bound to the driver via driver_override and passed through to a VM, its pf_qm stays NULL. The PCI error handler reset_prepare() runs during open_device through pci_try_reset_function(), before the mig_ops gate, and dereferences the NULL pf_qm for the timeout log, crashing the kernel. Move the mig_ops check to the entry of reset_prepare() and aer_reset_done() so non-migration devices skip the QM_RESETTING coordination. Also clear set_reset_flag together with QM_RESETTING in aer_reset_done(); the flag was never cleared before, so a later timed-out reset could release a foreign lock. Replace pci_iov_vf_id() >= 0 with pdev->is_virtfn in probe() for clearer on-VF gating. Fixes: b0eed085903e ("hisi_acc_vfio_pci: Add support for VFIO live migration") Fixes: a22099ed7936f ("hisi_acc_vfio_pci: fix VF reset timeout issue") Signed-off-by: Longfang Liu --- .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c index 86362ec424a5..8ff69c8d1ff7 100644 --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c @@ -1154,9 +1154,14 @@ static void hisi_acc_vf_pci_reset_prepare(struct pci_dev *pdev) { struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev); struct hisi_qm *qm = hisi_acc_vdev->pf_qm; - struct device *dev = &qm->pdev->dev; + struct device *dev = &pdev->dev; u32 delay = 0; + if (!hisi_acc_vdev->core_device.vdev.mig_ops) { + dev_err(dev, "device not support migration\n"); + return; + } + /* All reset requests need to be queued for processing */ while (test_and_set_bit(QM_RESETTING, &qm->misc_ctl)) { msleep(1); @@ -1174,12 +1179,14 @@ static void hisi_acc_vf_pci_aer_reset_done(struct pci_dev *pdev) struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev); struct hisi_qm *qm = hisi_acc_vdev->pf_qm; - if (hisi_acc_vdev->set_reset_flag) - clear_bit(QM_RESETTING, &qm->misc_ctl); - if (!hisi_acc_vdev->core_device.vdev.mig_ops) return; + if (hisi_acc_vdev->set_reset_flag) { + clear_bit(QM_RESETTING, &qm->misc_ctl); + hisi_acc_vdev->set_reset_flag = false; + } + mutex_lock(&hisi_acc_vdev->state_mutex); hisi_acc_vf_reset(hisi_acc_vdev); mutex_unlock(&hisi_acc_vdev->state_mutex); @@ -1670,13 +1677,11 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device struct hisi_acc_vf_core_device *hisi_acc_vdev; const struct vfio_device_ops *ops = &hisi_acc_vfio_pci_ops; struct hisi_qm *pf_qm; - int vf_id; int ret; pf_qm = hisi_acc_get_pf_qm(pdev); if (pf_qm && pf_qm->ver >= QM_HW_V3) { - vf_id = pci_iov_vf_id(pdev); - if (vf_id >= 0) + if (pdev->is_virtfn) ops = &hisi_acc_vfio_pci_migrn_ops; else pci_warn(pdev, "migration support failed, continue with generic interface\n"); -- 2.43.0