Jason Wang
2023-Jul-20 02:27 UTC
[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe
On Wed, Jul 19, 2023 at 11:46?PM Feng Liu <feliu at nvidia.com> wrote:> > The 'is_legacy' flag is used to differentiate between legacy vs modern > device. Currently, it is based on the value of vp_dev->ldev.ioaddr. > However, due to the shared memory of the union between struct > virtio_pci_legacy_device and struct virtio_pci_modern_device, when > virtio_pci_modern_probe modifies the content of struct > virtio_pci_modern_device, it affects the content of struct > virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing > the 'is_legacy' flag to be set as true. To resolve issue, when legacy > device is probed, mark 'is_legacy' as true, when modern device is > probed, keep 'is_legacy' as false. > > Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure size") > Signed-off-by: Feng Liu <feliu at nvidia.com> > Reviewed-by: Parav Pandit <parav at nvidia.com> > Reviewed-by: Jiri Pirko <jiri at nvidia.com> > --- > drivers/virtio/virtio_pci_common.c | 2 -- > drivers/virtio/virtio_pci_legacy.c | 1 + > 2 files changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > index a6c86f916dbd..c2524a7207cf 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev, > > pci_set_master(pci_dev); > > - vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false; > - > rc = register_virtio_device(&vp_dev->vdev); > reg_dev = vp_dev; > if (rc) > diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c > index 2257f1b3d8ae..d9cbb02b35a1 100644 > --- a/drivers/virtio/virtio_pci_legacy.c > +++ b/drivers/virtio/virtio_pci_legacy.c > @@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) > vp_dev->config_vector = vp_config_vector; > vp_dev->setup_vq = setup_vq; > vp_dev->del_vq = del_vq; > + vp_dev->is_legacy = true;This seems break force_legacy for modern device: if (force_legacy) { rc = virtio_pci_legacy_probe(vp_dev); /* Also try modern mode if we can't map BAR0 (no IO space). */ if (rc == -ENODEV || rc == -ENOMEM) rc = virtio_pci_modern_probe(vp_dev); Thanks> > return 0; > } > -- > 2.37.1 (Apple Git-137.1) >
Feng Liu
2023-Jul-20 02:46 UTC
[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe
On 2023-07-19 p.m.10:27, Jason Wang wrote:> External email: Use caution opening links or attachments > > > On Wed, Jul 19, 2023 at 11:46?PM Feng Liu <feliu at nvidia.com> wrote: >> >> The 'is_legacy' flag is used to differentiate between legacy vs modern >> device. Currently, it is based on the value of vp_dev->ldev.ioaddr. >> However, due to the shared memory of the union between struct >> virtio_pci_legacy_device and struct virtio_pci_modern_device, when >> virtio_pci_modern_probe modifies the content of struct >> virtio_pci_modern_device, it affects the content of struct >> virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing >> the 'is_legacy' flag to be set as true. To resolve issue, when legacy >> device is probed, mark 'is_legacy' as true, when modern device is >> probed, keep 'is_legacy' as false. >> >> Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure size") >> Signed-off-by: Feng Liu <feliu at nvidia.com> >> Reviewed-by: Parav Pandit <parav at nvidia.com> >> Reviewed-by: Jiri Pirko <jiri at nvidia.com> >> --- >> drivers/virtio/virtio_pci_common.c | 2 -- >> drivers/virtio/virtio_pci_legacy.c | 1 + >> 2 files changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c >> index a6c86f916dbd..c2524a7207cf 100644 >> --- a/drivers/virtio/virtio_pci_common.c >> +++ b/drivers/virtio/virtio_pci_common.c >> @@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev, >> >> pci_set_master(pci_dev); >> >> - vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false; >> - >> rc = register_virtio_device(&vp_dev->vdev); >> reg_dev = vp_dev; >> if (rc) >> diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c >> index 2257f1b3d8ae..d9cbb02b35a1 100644 >> --- a/drivers/virtio/virtio_pci_legacy.c >> +++ b/drivers/virtio/virtio_pci_legacy.c >> @@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) >> vp_dev->config_vector = vp_config_vector; >> vp_dev->setup_vq = setup_vq; >> vp_dev->del_vq = del_vq; >> + vp_dev->is_legacy = true; > > This seems break force_legacy for modern device: > > if (force_legacy) { > rc = virtio_pci_legacy_probe(vp_dev); > /* Also try modern mode if we can't map BAR0 (no IO space). */ > if (rc == -ENODEV || rc == -ENOMEM) > rc = virtio_pci_modern_probe(vp_dev); > > Thanks >Will do, thanks>> >> return 0; >> } >> -- >> 2.37.1 (Apple Git-137.1) >> >
Feng Liu
2023-Jul-20 16:43 UTC
[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe
On 2023-07-19 p.m.10:27, Jason Wang wrote:> External email: Use caution opening links or attachments > > > On Wed, Jul 19, 2023 at 11:46?PM Feng Liu <feliu at nvidia.com> wrote: >> >> The 'is_legacy' flag is used to differentiate between legacy vs modern >> device. Currently, it is based on the value of vp_dev->ldev.ioaddr. >> However, due to the shared memory of the union between struct >> virtio_pci_legacy_device and struct virtio_pci_modern_device, when >> virtio_pci_modern_probe modifies the content of struct >> virtio_pci_modern_device, it affects the content of struct >> virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing >> the 'is_legacy' flag to be set as true. To resolve issue, when legacy >> device is probed, mark 'is_legacy' as true, when modern device is >> probed, keep 'is_legacy' as false. >> >> Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure size") >> Signed-off-by: Feng Liu <feliu at nvidia.com> >> Reviewed-by: Parav Pandit <parav at nvidia.com> >> Reviewed-by: Jiri Pirko <jiri at nvidia.com> >> --- >> drivers/virtio/virtio_pci_common.c | 2 -- >> drivers/virtio/virtio_pci_legacy.c | 1 + >> 2 files changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c >> index a6c86f916dbd..c2524a7207cf 100644 >> --- a/drivers/virtio/virtio_pci_common.c >> +++ b/drivers/virtio/virtio_pci_common.c >> @@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev, >> >> pci_set_master(pci_dev); >> >> - vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false; >> - >> rc = register_virtio_device(&vp_dev->vdev); >> reg_dev = vp_dev; >> if (rc) >> diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c >> index 2257f1b3d8ae..d9cbb02b35a1 100644 >> --- a/drivers/virtio/virtio_pci_legacy.c >> +++ b/drivers/virtio/virtio_pci_legacy.c >> @@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) >> vp_dev->config_vector = vp_config_vector; >> vp_dev->setup_vq = setup_vq; >> vp_dev->del_vq = del_vq; >> + vp_dev->is_legacy = true; > > This seems break force_legacy for modern device: > > if (force_legacy) { > rc = virtio_pci_legacy_probe(vp_dev); > /* Also try modern mode if we can't map BAR0 (no IO space). */ > if (rc == -ENODEV || rc == -ENOMEM) > rc = virtio_pci_modern_probe(vp_dev); > > Thanks >Hi, Jason In the case of force_legacy, if no IO space occurs, function will return directly after vp_legacy_probe, and will not run vp_dev->is_legacy = true; because vp_dev is allocated through kzalloc, the default vp_dev->is_legacy is false, which It is expected for modern device, so it will not break modern device. What do you think? int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) { [...] rc = vp_legacy_probe(ldev); if (rc) return rc; /* if no IO space, function will return from here */ [...] vp_dev->is_legacy = true; }>> >> return 0; >> } >> -- >> 2.37.1 (Apple Git-137.1) >> >
Michael S. Tsirkin
2023-Jul-20 17:14 UTC
[PATCH v1] virtio-pci: Fix legacy device flag setting error in probe
On Thu, Jul 20, 2023 at 10:27:04AM +0800, Jason Wang wrote:> On Wed, Jul 19, 2023 at 11:46?PM Feng Liu <feliu at nvidia.com> wrote: > > > > The 'is_legacy' flag is used to differentiate between legacy vs modern > > device. Currently, it is based on the value of vp_dev->ldev.ioaddr. > > However, due to the shared memory of the union between struct > > virtio_pci_legacy_device and struct virtio_pci_modern_device, when > > virtio_pci_modern_probe modifies the content of struct > > virtio_pci_modern_device, it affects the content of struct > > virtio_pci_legacy_device, and ldev.ioaddr is no longer zero, causing > > the 'is_legacy' flag to be set as true. To resolve issue, when legacy > > device is probed, mark 'is_legacy' as true, when modern device is > > probed, keep 'is_legacy' as false. > > > > Fixes: 4f0fc22534e3 ("virtio_pci: Optimize virtio_pci_device structure size") > > Signed-off-by: Feng Liu <feliu at nvidia.com> > > Reviewed-by: Parav Pandit <parav at nvidia.com> > > Reviewed-by: Jiri Pirko <jiri at nvidia.com> > > --- > > drivers/virtio/virtio_pci_common.c | 2 -- > > drivers/virtio/virtio_pci_legacy.c | 1 + > > 2 files changed, 1 insertion(+), 2 deletions(-) > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > index a6c86f916dbd..c2524a7207cf 100644 > > --- a/drivers/virtio/virtio_pci_common.c > > +++ b/drivers/virtio/virtio_pci_common.c > > @@ -557,8 +557,6 @@ static int virtio_pci_probe(struct pci_dev *pci_dev, > > > > pci_set_master(pci_dev); > > > > - vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false; > > - > > rc = register_virtio_device(&vp_dev->vdev); > > reg_dev = vp_dev; > > if (rc) > > diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c > > index 2257f1b3d8ae..d9cbb02b35a1 100644 > > --- a/drivers/virtio/virtio_pci_legacy.c > > +++ b/drivers/virtio/virtio_pci_legacy.c > > @@ -223,6 +223,7 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) > > vp_dev->config_vector = vp_config_vector; > > vp_dev->setup_vq = setup_vq; > > vp_dev->del_vq = del_vq; > > + vp_dev->is_legacy = true; > > This seems break force_legacy for modern device: > > if (force_legacy) { > rc = virtio_pci_legacy_probe(vp_dev); > /* Also try modern mode if we can't map BAR0 (no IO space). */ > if (rc == -ENODEV || rc == -ENOMEM) > rc = virtio_pci_modern_probe(vp_dev); > > Thanksdon't see the breakage here - can you explain a bit more?> > > > return 0; > > } > > -- > > 2.37.1 (Apple Git-137.1) > >