| 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: <20251120123647.3522082-7-michal.winiarski@intel.com>
Date: Thu, 20 Nov 2025 13:36:47 +0100
From: Michał Winiarski <michal.winiarski@...el.com>
To: Jason Gunthorpe <jgg@...pe.ca>, Alex Williamson <alex@...zbot.org>, "Kevin
Tian" <kevin.tian@...el.com>, Yishai Hadas <yishaih@...dia.com>, Longfang Liu
<liulongfang@...wei.com>, Shameer Kolothum <skolothumtho@...dia.com>, "Brett
Creeley" <brett.creeley@....com>, Giovanni Cabiddu
<giovanni.cabiddu@...el.com>, <kvm@...r.kernel.org>, <qat-linux@...el.com>,
<virtualization@...ts.linux.dev>, <linux-kernel@...r.kernel.org>
CC: Michał Winiarski <michal.winiarski@...el.com>
Subject: [PATCH 6/6] vfio/virtio: Use .migration_reset_state() callback
Move the migration device state reset code from .reset_done() to
dedicated callback.
Remove the deferred reset mechanism, as it's no longer needed.
Signed-off-by: Michał Winiarski <michal.winiarski@...el.com>
---
drivers/vfio/pci/virtio/common.h | 3 --
drivers/vfio/pci/virtio/main.c | 1 -
drivers/vfio/pci/virtio/migrate.c | 71 +++++++++----------------------
3 files changed, 21 insertions(+), 54 deletions(-)
diff --git a/drivers/vfio/pci/virtio/common.h b/drivers/vfio/pci/virtio/common.h
index c7d7e27af386e..cb27d3d2d3bb9 100644
--- a/drivers/vfio/pci/virtio/common.h
+++ b/drivers/vfio/pci/virtio/common.h
@@ -92,12 +92,9 @@ struct virtiovf_pci_core_device {
/* LM related */
u8 migrate_cap:1;
- u8 deferred_reset:1;
/* protect migration state */
struct mutex state_mutex;
enum vfio_device_mig_state mig_state;
- /* protect the reset_done flow */
- spinlock_t reset_lock;
struct virtiovf_migration_file *resuming_migf;
struct virtiovf_migration_file *saving_migf;
};
diff --git a/drivers/vfio/pci/virtio/main.c b/drivers/vfio/pci/virtio/main.c
index 8084f3e36a9f7..b80cb740f9a5d 100644
--- a/drivers/vfio/pci/virtio/main.c
+++ b/drivers/vfio/pci/virtio/main.c
@@ -203,7 +203,6 @@ static void virtiovf_pci_aer_reset_done(struct pci_dev *pdev)
#ifdef CONFIG_VIRTIO_VFIO_PCI_ADMIN_LEGACY
virtiovf_legacy_io_reset_done(pdev);
#endif
- virtiovf_migration_reset_done(pdev);
}
static const struct pci_error_handlers virtiovf_err_handlers = {
diff --git a/drivers/vfio/pci/virtio/migrate.c b/drivers/vfio/pci/virtio/migrate.c
index 7dd0ac866461d..5c7f9091d84e8 100644
--- a/drivers/vfio/pci/virtio/migrate.c
+++ b/drivers/vfio/pci/virtio/migrate.c
@@ -247,49 +247,6 @@ static void virtiovf_disable_fds(struct virtiovf_pci_core_device *virtvdev)
}
}
-/*
- * This function is called in all state_mutex unlock cases to
- * handle a 'deferred_reset' if exists.
- */
-static void virtiovf_state_mutex_unlock(struct virtiovf_pci_core_device *virtvdev)
-{
-again:
- spin_lock(&virtvdev->reset_lock);
- if (virtvdev->deferred_reset) {
- virtvdev->deferred_reset = false;
- spin_unlock(&virtvdev->reset_lock);
- virtvdev->mig_state = VFIO_DEVICE_STATE_RUNNING;
- virtiovf_disable_fds(virtvdev);
- goto again;
- }
- mutex_unlock(&virtvdev->state_mutex);
- spin_unlock(&virtvdev->reset_lock);
-}
-
-void virtiovf_migration_reset_done(struct pci_dev *pdev)
-{
- struct virtiovf_pci_core_device *virtvdev = dev_get_drvdata(&pdev->dev);
-
- if (!virtvdev->migrate_cap)
- return;
-
- /*
- * As the higher VFIO layers are holding locks across reset and using
- * those same locks with the mm_lock we need to prevent ABBA deadlock
- * with the state_mutex and mm_lock.
- * In case the state_mutex was taken already we defer the cleanup work
- * to the unlock flow of the other running context.
- */
- spin_lock(&virtvdev->reset_lock);
- virtvdev->deferred_reset = true;
- if (!mutex_trylock(&virtvdev->state_mutex)) {
- spin_unlock(&virtvdev->reset_lock);
- return;
- }
- spin_unlock(&virtvdev->reset_lock);
- virtiovf_state_mutex_unlock(virtvdev);
-}
-
static int virtiovf_release_file(struct inode *inode, struct file *filp)
{
struct virtiovf_migration_file *migf = filp->private_data;
@@ -513,7 +470,7 @@ static long virtiovf_precopy_ioctl(struct file *filp, unsigned int cmd,
goto err_state_unlock;
done:
- virtiovf_state_mutex_unlock(virtvdev);
+ mutex_unlock(&virtvdev->state_mutex);
if (copy_to_user((void __user *)arg, &info, minsz))
return -EFAULT;
return 0;
@@ -521,7 +478,7 @@ static long virtiovf_precopy_ioctl(struct file *filp, unsigned int cmd,
err_migf_unlock:
mutex_unlock(&migf->lock);
err_state_unlock:
- virtiovf_state_mutex_unlock(virtvdev);
+ mutex_unlock(&virtvdev->state_mutex);
return ret;
}
@@ -1048,7 +1005,7 @@ static ssize_t virtiovf_resume_write(struct file *filp, const char __user *buf,
if (ret)
migf->state = VIRTIOVF_MIGF_STATE_ERROR;
mutex_unlock(&migf->lock);
- virtiovf_state_mutex_unlock(migf->virtvdev);
+ mutex_unlock(&migf->virtvdev->state_mutex);
return ret ? ret : done;
}
@@ -1245,7 +1202,7 @@ virtiovf_pci_set_device_state(struct vfio_device *vdev,
break;
}
}
- virtiovf_state_mutex_unlock(virtvdev);
+ mutex_unlock(&virtvdev->state_mutex);
return res;
}
@@ -1257,10 +1214,24 @@ static int virtiovf_pci_get_device_state(struct vfio_device *vdev,
mutex_lock(&virtvdev->state_mutex);
*curr_state = virtvdev->mig_state;
- virtiovf_state_mutex_unlock(virtvdev);
+ mutex_unlock(&virtvdev->state_mutex);
return 0;
}
+static void virtiovf_pci_reset_device_state(struct vfio_device *vdev)
+{
+ struct virtiovf_pci_core_device *virtvdev = container_of(
+ vdev, struct virtiovf_pci_core_device, core_device.vdev);
+
+ if (!virtvdev->migrate_cap)
+ return;
+
+ mutex_lock(&virtvdev->state_mutex);
+ virtvdev->mig_state = VFIO_DEVICE_STATE_RUNNING;
+ virtiovf_disable_fds(virtvdev);
+ mutex_unlock(&virtvdev->state_mutex);
+}
+
static int virtiovf_pci_get_data_size(struct vfio_device *vdev,
unsigned long *stop_copy_length)
{
@@ -1297,13 +1268,14 @@ static int virtiovf_pci_get_data_size(struct vfio_device *vdev,
if (!obj_id_exists)
virtiovf_pci_free_obj_id(virtvdev, obj_id);
end:
- virtiovf_state_mutex_unlock(virtvdev);
+ mutex_unlock(&virtvdev->state_mutex);
return ret;
}
static const struct vfio_migration_ops virtvdev_pci_mig_ops = {
.migration_set_state = virtiovf_pci_set_device_state,
.migration_get_state = virtiovf_pci_get_device_state,
+ .migration_reset_state = virtiovf_pci_reset_device_state,
.migration_get_data_size = virtiovf_pci_get_data_size,
};
@@ -1311,7 +1283,6 @@ void virtiovf_set_migratable(struct virtiovf_pci_core_device *virtvdev)
{
virtvdev->migrate_cap = 1;
mutex_init(&virtvdev->state_mutex);
- spin_lock_init(&virtvdev->reset_lock);
virtvdev->core_device.vdev.migration_flags =
VFIO_MIGRATION_STOP_COPY |
VFIO_MIGRATION_P2P |
--
2.51.2
Powered by blists - more mailing lists