| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <Y8WKfcWrBHvgh11E@nvidia.com>
Date: Mon, 16 Jan 2023 13:33:49 -0400
From: Jason Gunthorpe <jgg@...dia.com>
To: Longfang Liu <liulongfang@...wei.com>
Cc: alex.williamson@...hat.com, shameerali.kolothum.thodi@...wei.com,
jonathan.cameron@...wei.com, cohuck@...hat.com,
linux-kernel@...r.kernel.org, linuxarm@...neuler.org
Subject: Re: [PATCH v6 1/5] vfio/migration: Add debugfs to live migration
driver
On Sat, Jan 14, 2023 at 05:26:11PM +0800, Longfang Liu wrote:
> There are multiple devices, software and operational steps involved
> in the process of live migration. An error occurred on any node may
> cause the live migration operation to fail.
> This complex process makes it very difficult to locate and analyze
> the cause when the function fails.
>
> In order to quickly locate the cause of the problem when the
> live migration fails, I added a set of debugfs to the vfio
> live migration driver.
>
> +------------------------------------------+
> | |
> | |
> | QEMU |
> | |
> | |
> +-----+-------------------------+----------+
> | ^ | ^
> v | v |
> +-----+--+ +-----+--+
> | src VF | | dst VF |
> +-+------+ +-+------+
> | ^ | ^
> v | v |
> +-------+-+------+ +-------+-+------+
> |Debugfs|state | |Debugfs|state |
> +-------+--------+ +-------+--------+
> | debug_root | | debug_root |
> +-------+--------+ +-------+--------+
>
> The entire debugfs directory will be based on the definition of
> the CONFIG_DEBUG_FS macro. If this macro is not enabled, the
> interfaces in vfio_pci_debugfs.h will be empty definitions,
> and the creation and initialization of the debugfs directory
> will not be executed.
>
> debugfs will create a public root directory "vfio_mig" file.
> then create a "debug_root" file for each live migration VF device.
> state file: used to get the status of the live migration device.
> debug_root: used to create your own custom debug files for live
> migration device drivers.
>
> The live migration function of the current device can be tested by
> operating the debug files, and the functional status of the equipment
> and software at each stage can be tested step by step without
> performing the complete live migration function. And after the live
> migration is performed, the migration device data of the live migration
> can be obtained through the debug files.
>
> Signed-off-by: Longfang Liu <liulongfang@...wei.com>
> ---
> drivers/vfio/pci/Makefile | 1 +
> drivers/vfio/pci/vfio_pci_core.c | 3 ++
> drivers/vfio/pci/vfio_pci_debugfs.c | 82 +++++++++++++++++++++++++++++
> drivers/vfio/pci/vfio_pci_debugfs.h | 30 +++++++++++
> include/linux/vfio.h | 6 +++
> 5 files changed, 122 insertions(+)
> create mode 100644 drivers/vfio/pci/vfio_pci_debugfs.c
> create mode 100644 drivers/vfio/pci/vfio_pci_debugfs.h
>
> diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile
> index 24c524224da5..75fe37e72e8d 100644
> --- a/drivers/vfio/pci/Makefile
> +++ b/drivers/vfio/pci/Makefile
> @@ -2,6 +2,7 @@
>
> vfio-pci-core-y := vfio_pci_core.o vfio_pci_intrs.o vfio_pci_rdwr.o vfio_pci_config.o
> vfio-pci-core-$(CONFIG_VFIO_PCI_ZDEV_KVM) += vfio_pci_zdev.o
> +vfio-pci-core-$(CONFIG_DEBUG_FS) += vfio_pci_debugfs.o
> obj-$(CONFIG_VFIO_PCI_CORE) += vfio-pci-core.o
>
> vfio-pci-y := vfio_pci.o
> diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
> index f9365a5bc961..e85df2deb8e6 100644
> --- a/drivers/vfio/pci/vfio_pci_core.c
> +++ b/drivers/vfio/pci/vfio_pci_core.c
> @@ -31,6 +31,7 @@
> #include <asm/eeh.h>
> #endif
>
> +#include "vfio_pci_debugfs.h"
> #include "vfio_pci_priv.h"
>
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@...hat.com>"
> @@ -2555,11 +2556,13 @@ EXPORT_SYMBOL_GPL(vfio_pci_core_set_params);
>
> static void vfio_pci_core_cleanup(void)
> {
> + vfio_pci_debugfs_remove_root();
> vfio_pci_uninit_perm_bits();
> }
>
> static int __init vfio_pci_core_init(void)
> {
> + vfio_pci_debugfs_create_root();
> /* Allocate shared config space permission data used by all devices */
> return vfio_pci_init_perm_bits();
> }
> diff --git a/drivers/vfio/pci/vfio_pci_debugfs.c b/drivers/vfio/pci/vfio_pci_debugfs.c
> new file mode 100644
> index 000000000000..169570de7ccb
> --- /dev/null
> +++ b/drivers/vfio/pci/vfio_pci_debugfs.c
> @@ -0,0 +1,82 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2022, HiSilicon Ltd.
> + */
> +
> +#include <linux/pci.h>
> +#include <linux/vfio_pci_core.h>
> +
> +#include "vfio_pci_debugfs.h"
> +
> +static struct dentry *vfio_pci_debugfs_root;
> +
> +static int vfio_pci_vf_state_read(struct seq_file *seq, void *data)
> +{
> + struct device *vf_dev = seq->private;
> + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev);
> + struct vfio_device *vdev = &core_device->vdev;
> + enum vfio_device_mig_state state;
> + int ret;
> +
> + ret = vdev->mig_ops->migration_get_state(vdev, &state);
> + if (ret) {
> + dev_err("failed to get device migration state");
Don't print
> + return -EINVAL;
> + }
> +
> + switch (state) {
> + case VFIO_DEVICE_STATE_RUNNING:
> + seq_printf(seq, "%s\n", "RUNNING");
> + break;
> + case VFIO_DEVICE_STATE_STOP_COPY:
> + seq_printf(seq, "%s\n", "STOP_COPY");
> + break;
> + case VFIO_DEVICE_STATE_STOP:
> + seq_printf(seq, "%s\n", "STOP");
> + break;
> + case VFIO_DEVICE_STATE_RESUMING:
> + seq_printf(seq, "%s\n", "RESUMING");
> + break;
> + case VFIO_DEVICE_STATE_RUNNING_P2P:
> + seq_printf(seq, "%s\n", "RESUMING_P2P");
> + break;
> + case VFIO_DEVICE_STATE_ERROR:
> + seq_printf(seq, "%s\n", "ERROR");
> + break;
> + default:
> + seq_printf(seq, "%s\n", "Invalid");
> + }
> +
> + return 0;
> +}
> +
> +void vfio_pci_vf_debugfs_init(struct vfio_device *vdev)
> +{
> + struct device *dev = vdev->dev;
> +
> + vdev->debug_root = debugfs_create_dir(dev_name(dev), vfio_pci_debugfs_root);
> +
> + debugfs_create_devm_seqfile(dev, "state", vdev->debug_root,
> + vfio_pci_vf_state_read);
> +}
> +EXPORT_SYMBOL_GPL(vfio_pci_vf_debugfs_init);
> +
> +void vfio_pci_vf_debugfs_exit(struct vfio_device *vdev)
> +{
> + debugfs_remove_recursive(vdev->debug_root);
> +}
> +EXPORT_SYMBOL_GPL(vfio_pci_vf_debugfs_exit);
> +
> +void vfio_pci_debugfs_create_root(void)
> +{
> + vfio_pci_debugfs_root = debugfs_create_dir("vfio_mig", NULL);
> +}
> +EXPORT_SYMBOL_GPL(vfio_pci_debugfs_create_root);
> +
> +void vfio_pci_debugfs_remove_root(void)
> +{
> + debugfs_remove_recursive(vfio_pci_debugfs_root);
> + vfio_pci_debugfs_root = NULL;
> +}
> +EXPORT_SYMBOL_GPL(vfio_pci_debugfs_remove_root);
> +
> diff --git a/drivers/vfio/pci/vfio_pci_debugfs.h b/drivers/vfio/pci/vfio_pci_debugfs.h
> new file mode 100644
> index 000000000000..8d1a4aef05db
> --- /dev/null
> +++ b/drivers/vfio/pci/vfio_pci_debugfs.h
> @@ -0,0 +1,30 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * vfio_pci_debugfs.h - VFIO migration debugfs interface
> + *
> + * Copyright (c) 2022, HiSilicon Ltd.
> + *
> + * Author: Longfang Liu <liulongfang@...wei.com>
> + */
> +
> +#ifndef __VFIO_PCI_DEBUGFS_H
> +#define __VFIO_PCI_DEBUGFS_H
> +
> +#include <linux/debugfs.h>
> +#include <linux/vfio.h>
> +
> +#ifdef CONFIG_DEBUG_FS
> +void vfio_pci_debugfs_create_root(void);
> +void vfio_pci_debugfs_remove_root(void);
extra whitespace
> +void vfio_pci_vf_debugfs_init(struct vfio_device *vdev);
> +void vfio_pci_vf_debugfs_exit(struct vfio_device *vdev);
> +#else
> +static inline void vfio_pci_debugfs_create_root(void) { }
> +static inline void vfio_pci_debugfs_remove_root(void) { }
> +
> +static inline void vfio_pci_vf_debugfs_init(struct vfio_device *vdev) { }
> +static inline void vfio_pci_vf_debugfs_exit(struct vfio_device *vdev) { }
> +#endif /* CONFIG_DEBUG_FS */
Just {}
> +
> +#endif /* __VFIO_PCI_DEBUGFS_H */
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index b4d5d4ca3d7d..7d6d02f165cf 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -54,6 +54,12 @@ struct vfio_device {
> struct completion comp;
> struct list_head group_next;
> struct list_head iommu_entry;
> +
> + /*
> + * debug_root is a static property of the vfio_device
> + * which must be set prior to registering the vfio_device.
> + */
> + struct dentry *debug_root;
This should be ifdefd too if you are doing it like this
Jason
Powered by blists - more mailing lists