On Sat, Oct 31, 2020 at 6:09 AM Luben Tuikov <[email protected]> wrote: > > On 2020-10-30 08:04, Daniel Vetter wrote: > > On Fri, Oct 30, 2020 at 11:41 AM Liu, Monk <[email protected]> wrote: > >> > >> [AMD Official Use Only - Internal Distribution Only] > >> > >> What's the purpose of the patch sets > >> > >> e.g.: what bug can those 5 patches fix or what feature provided > >> > >> for this particular one (3/5) I didn't see how it helpful, could you give > >> a background ? > > > > It's good to make function tables const, so that they can be write > > protected. More resilience against exploits and all that. This patch > > here is needed to be able to make drm_device->driver const so that all > > other drivers can make their drm_driver structure const. Would be good > > to fully fix up amdgpu like in the comment, but I'm not going that in > > this series here. > > -Daniel > > Hi Daniel, > > I feel that that's a good change. > > But if you can clarify this for me... Is this leading > towards a single instance of a struct drm_driver per > low-level driver, i.e. amdgpu? > > And as such, being able to be defined as const? > > So that we have many GPU devices driven by one > low-level driver (amdgpu_drv), represented by one > const drm_driver (and thus const)? > > Which would imply that if varied devices can be handled > by a single low-level driver, whose struct drm_driver > settings cannot be shared among subset of devices (say > very old and new), then the low-level driver > would have to create more than one "const" struct drm_driver?
This is already the case, minus the const. Which is why it's problemantic if you change that shared drm_driver instance at runtime from a specific driver, since you always change it for all instances. -Daniel > > Regards, > Luben > > > > >> > >> thanks > >> _____________________________________ > >> Monk Liu|GPU Virtualization Team |AMD > >> > >> > >> -----Original Message----- > >> From: Daniel Vetter <[email protected]> > >> Sent: Friday, October 30, 2020 6:11 PM > >> To: DRI Development <[email protected]> > >> Cc: Intel Graphics Development <[email protected]>; Daniel > >> Vetter <[email protected]>; Deucher, Alexander > >> <[email protected]>; Koenig, Christian <[email protected]>; > >> Quan, Evan <[email protected]>; Kuehling, Felix <[email protected]>; > >> Zhang, Hawking <[email protected]>; Grodzovsky, Andrey > >> <[email protected]>; Tuikov, Luben <[email protected]>; Thomas > >> Zimmermann <[email protected]>; Liu, Monk <[email protected]>; Yintian > >> Tao <[email protected]>; Li, Dennis <[email protected]>; Liu, Shaoyun > >> <[email protected]>; Zhang, Bokun <[email protected]>; Yang, Stanley > >> <[email protected]>; Sheng, Wenhui <[email protected]>; Gong, Curry > >> <[email protected]>; Daniel Vetter <[email protected]> > >> Subject: [PATCH 3/5] drm/amdgpu: Paper over the drm_driver mangling for > >> virt > >> > >> Prep work to make drm_device->driver const. > >> > >> Signed-off-by: Daniel Vetter <[email protected]> > >> Cc: Alex Deucher <[email protected]> > >> Cc: "Christian König" <[email protected]> > >> Cc: Evan Quan <[email protected]> > >> Cc: Felix Kuehling <[email protected]> > >> Cc: Hawking Zhang <[email protected]> > >> Cc: Andrey Grodzovsky <[email protected]> > >> Cc: Luben Tuikov <[email protected]> > >> Cc: Thomas Zimmermann <[email protected]> > >> Cc: Monk Liu <[email protected]> > >> Cc: Yintian Tao <[email protected]> > >> Cc: Dennis Li <[email protected]> > >> Cc: shaoyunl <[email protected]> > >> Cc: Bokun Zhang <[email protected]> > >> Cc: "Stanley.Yang" <[email protected]> > >> Cc: Wenhui Sheng <[email protected]> > >> Cc: chen gong <[email protected]> > >> Signed-off-by: Daniel Vetter <[email protected]> > >> --- > >> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 8 ++++---- > >> drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 12 +++++++++++- > >> 2 files changed, 15 insertions(+), 5 deletions(-) > >> > >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >> index 024c3b70b1aa..3d337f13ae4e 100644 > >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >> @@ -1093,7 +1093,7 @@ static const struct pci_device_id pciidlist[] = { > >> > >> MODULE_DEVICE_TABLE(pci, pciidlist); > >> > >> -static struct drm_driver kms_driver; > >> +struct drm_driver amdgpu_kms_driver; > >> > >> static int amdgpu_pci_probe(struct pci_dev *pdev, > >> const struct pci_device_id *ent) @@ -1164,7 +1164,7 @@ static int > >> amdgpu_pci_probe(struct pci_dev *pdev, > >> if (ret) > >> return ret; > >> > >> -adev = devm_drm_dev_alloc(&pdev->dev, &kms_driver, typeof(*adev), ddev); > >> +adev = devm_drm_dev_alloc(&pdev->dev, &amdgpu_kms_driver, > >> +typeof(*adev), ddev); > >> if (IS_ERR(adev)) > >> return PTR_ERR(adev); > >> > >> @@ -1508,7 +1508,7 @@ int amdgpu_file_to_fpriv(struct file *filp, struct > >> amdgpu_fpriv **fpriv) > >> return 0; > >> } > >> > >> -static struct drm_driver kms_driver = { > >> +struct drm_driver amdgpu_kms_driver = { > >> .driver_features = > >> DRIVER_ATOMIC | > >> DRIVER_GEM | > >> @@ -1571,7 +1571,7 @@ static int __init amdgpu_init(void) > >> goto error_fence; > >> > >> DRM_INFO("amdgpu kernel modesetting enabled.\n"); > >> -kms_driver.num_ioctls = amdgpu_max_kms_ioctl; > >> +amdgpu_kms_driver.num_ioctls = amdgpu_max_kms_ioctl; > >> amdgpu_register_atpx_handler(); > >> > >> /* Ignore KFD init failures. Normal when CONFIG_HSA_AMD is not set. */ > >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c > >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c > >> index d0aea5e39531..dde4c449c284 100644 > >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c > >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c > >> @@ -45,13 +45,23 @@ bool amdgpu_virt_mmio_blocked(struct amdgpu_device > >> *adev) > >> return RREG32_NO_KIQ(0xc040) == 0xffffffff; } > >> > >> +extern struct drm_driver amdgpu_kms_driver; > >> + > >> void amdgpu_virt_init_setting(struct amdgpu_device *adev) { > >> /* enable virtual display */ > >> if (adev->mode_info.num_crtc == 0) > >> adev->mode_info.num_crtc = 1; > >> adev->enable_virtual_display = true; > >> -adev_to_drm(adev)->driver->driver_features &= ~DRIVER_ATOMIC; > >> + > >> +/* > >> + * FIXME: Either make virt support atomic or make sure you have two > >> + * drm_driver structs, these kind of tricks are only ok when there's > >> + * guaranteed only a single device per system. This should also be done > >> + * before struct drm_device is initialized. > >> + */ > >> +amdgpu_kms_driver.driver_features &= ~DRIVER_ATOMIC; > >> + > >> adev->cg_flags = 0; > >> adev->pg_flags = 0; > >> } > >> -- > >> 2.28.0 > >> > > > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
