[+cc Bartosz] On Fri, Feb 02, 2024 at 05:25:56PM -0500, Hamza Mahfooz wrote: > Removing an amdgpu device that still has user space references allocated > to it causes undefined behaviour. So, implement amdgpu_pci_can_remove() > and disallow devices that still have files allocated to them from being > unbound. Maybe this would help for things that are completely built-in or soldered down, but nothing can prevent a user from physically pulling a card or cable, so I don't think this is a generic solution to the problem of dangling user space references. Maybe Bartosz's recent LPC talk is relevant: https://lpc.events/event/17/contributions/1627/ > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Hamza Mahfooz <hamza.mahfooz@xxxxxxx> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > index cc69005f5b46..cfa64f3c5be5 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > @@ -2323,6 +2323,22 @@ static int amdgpu_pci_probe(struct pci_dev *pdev, > return ret; > } > > +static bool amdgpu_pci_can_remove(struct pci_dev *pdev) > +{ > + struct drm_device *dev = pci_get_drvdata(pdev); > + > + mutex_lock(&dev->filelist_mutex); > + > + if (!list_empty(&dev->filelist)) { > + mutex_unlock(&dev->filelist_mutex); > + return false; > + } > + > + mutex_unlock(&dev->filelist_mutex); > + > + return true; > +} > + > static void > amdgpu_pci_remove(struct pci_dev *pdev) > { > @@ -2929,6 +2945,7 @@ static struct pci_driver amdgpu_kms_pci_driver = { > .name = DRIVER_NAME, > .id_table = pciidlist, > .probe = amdgpu_pci_probe, > + .can_remove = amdgpu_pci_can_remove, > .remove = amdgpu_pci_remove, > .shutdown = amdgpu_pci_shutdown, > .driver.pm = &amdgpu_pm_ops, > -- > 2.43.0 >
