Commit 17b17be2 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'vfio-v6.7-rc4' of https://github.com/awilliam/linux-vfio 

Pull vfio fixes from Alex Williamson:

 - Fix the lifecycle of a mutex in the pds variant driver such that a
   reset prior to opening the device won't find it uninitialized.
   Implement the release path to symmetrically destroy the mutex. Also
   switch a different lock from spinlock to mutex as the code path has
   the potential to sleep and doesn't need the spinlock context
   otherwise (Brett Creeley)

 - Fix an issue detected via randconfig where KVM tries to symbol_get an
   undeclared function. The symbol is temporarily declared
   unconditionally here, which resolves the problem and avoids churn
   relative to a series pending for the next merge window which resolves
   some of this symbol ugliness, but also fixes Kconfig dependencies
   (Sean Christopherson)

* tag 'vfio-v6.7-rc4' of https://github.com/awilliam/linux-vfio:
  vfio: Drop vfio_file_iommu_group() stub to fudge around a KVM wart
  vfio/pds: Fix possible sleep while in atomic context
  vfio/pds: Fix mutex lock->magic != lock warning
parents deb4b9dd 4ea95c04

drivers/vfio/pci/pds/pci_drv.c

+2 −2
Original line number Diff line number Diff line
@@ -55,10 +55,10 @@ static void pds_vfio_recovery(struct pds_vfio_pci_device *pds_vfio) 
	 * VFIO_DEVICE_STATE_RUNNING.

	 */

	if (deferred_reset_needed) {

		spin_lock(&pds_vfio->reset_lock);

		mutex_lock(&pds_vfio->reset_mutex);

		pds_vfio->deferred_reset = true;

		pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_ERROR;

		spin_unlock(&pds_vfio->reset_lock);

		mutex_unlock(&pds_vfio->reset_mutex);

	}

}

drivers/vfio/pci/pds/vfio_dev.c

+21 −9
Original line number Diff line number Diff line
@@ -29,7 +29,7 @@ struct pds_vfio_pci_device *pds_vfio_pci_drvdata(struct pci_dev *pdev) 
void pds_vfio_state_mutex_unlock(struct pds_vfio_pci_device *pds_vfio)

{

again:

	spin_lock(&pds_vfio->reset_lock);

	mutex_lock(&pds_vfio->reset_mutex);

	if (pds_vfio->deferred_reset) {

		pds_vfio->deferred_reset = false;

		if (pds_vfio->state == VFIO_DEVICE_STATE_ERROR) {
@@ -39,23 +39,23 @@ void pds_vfio_state_mutex_unlock(struct pds_vfio_pci_device *pds_vfio) 
		}

		pds_vfio->state = pds_vfio->deferred_reset_state;

		pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;

		spin_unlock(&pds_vfio->reset_lock);

		mutex_unlock(&pds_vfio->reset_mutex);

		goto again;

	}

	mutex_unlock(&pds_vfio->state_mutex);

	spin_unlock(&pds_vfio->reset_lock);

	mutex_unlock(&pds_vfio->reset_mutex);

}



void pds_vfio_reset(struct pds_vfio_pci_device *pds_vfio)

{

	spin_lock(&pds_vfio->reset_lock);

	mutex_lock(&pds_vfio->reset_mutex);

	pds_vfio->deferred_reset = true;

	pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;

	if (!mutex_trylock(&pds_vfio->state_mutex)) {

		spin_unlock(&pds_vfio->reset_lock);

		mutex_unlock(&pds_vfio->reset_mutex);

		return;

	}

	spin_unlock(&pds_vfio->reset_lock);

	mutex_unlock(&pds_vfio->reset_mutex);

	pds_vfio_state_mutex_unlock(pds_vfio);

}
@@ -155,6 +155,9 @@ static int pds_vfio_init_device(struct vfio_device *vdev) 


	pds_vfio->vf_id = vf_id;



	mutex_init(&pds_vfio->state_mutex);

	mutex_init(&pds_vfio->reset_mutex);



	vdev->migration_flags = VFIO_MIGRATION_STOP_COPY | VFIO_MIGRATION_P2P;

	vdev->mig_ops = &pds_vfio_lm_ops;

	vdev->log_ops = &pds_vfio_log_ops;
@@ -168,6 +171,17 @@ static int pds_vfio_init_device(struct vfio_device *vdev) 
	return 0;

}



static void pds_vfio_release_device(struct vfio_device *vdev)

{

	struct pds_vfio_pci_device *pds_vfio =

		container_of(vdev, struct pds_vfio_pci_device,

			     vfio_coredev.vdev);



	mutex_destroy(&pds_vfio->state_mutex);

	mutex_destroy(&pds_vfio->reset_mutex);

	vfio_pci_core_release_dev(vdev);

}



static int pds_vfio_open_device(struct vfio_device *vdev)

{

	struct pds_vfio_pci_device *pds_vfio =
@@ -179,7 +193,6 @@ static int pds_vfio_open_device(struct vfio_device *vdev) 
	if (err)

		return err;



	mutex_init(&pds_vfio->state_mutex);

	pds_vfio->state = VFIO_DEVICE_STATE_RUNNING;

	pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
@@ -199,14 +212,13 @@ static void pds_vfio_close_device(struct vfio_device *vdev) 
	pds_vfio_put_save_file(pds_vfio);

	pds_vfio_dirty_disable(pds_vfio, true);

	mutex_unlock(&pds_vfio->state_mutex);

	mutex_destroy(&pds_vfio->state_mutex);

	vfio_pci_core_close_device(vdev);

}



static const struct vfio_device_ops pds_vfio_ops = {

	.name = "pds-vfio",

	.init = pds_vfio_init_device,

	.release = vfio_pci_core_release_dev,

	.release = pds_vfio_release_device,

	.open_device = pds_vfio_open_device,

	.close_device = pds_vfio_close_device,

	.ioctl = vfio_pci_core_ioctl,

drivers/vfio/pci/pds/vfio_dev.h

+1 −1
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ struct pds_vfio_pci_device { 
	struct pds_vfio_dirty dirty;

	struct mutex state_mutex; /* protect migration state */

	enum vfio_device_mig_state state;

	spinlock_t reset_lock; /* protect reset_done flow */

	struct mutex reset_mutex; /* protect reset_done flow */

	u8 deferred_reset;

	enum vfio_device_mig_state deferred_reset_state;

	struct notifier_block nb;

include/linux/vfio.h

+2 −6
Original line number Diff line number Diff line
@@ -289,16 +289,12 @@ void vfio_combine_iova_ranges(struct rb_root_cached *root, u32 cur_nodes, 
/*

 * External user API

 */

#if IS_ENABLED(CONFIG_VFIO_GROUP)

struct iommu_group *vfio_file_iommu_group(struct file *file);



#if IS_ENABLED(CONFIG_VFIO_GROUP)

bool vfio_file_is_group(struct file *file);

bool vfio_file_has_dev(struct file *file, struct vfio_device *device);

#else

static inline struct iommu_group *vfio_file_iommu_group(struct file *file)

{

	return NULL;

}



static inline bool vfio_file_is_group(struct file *file)

{

	return false;