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? 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 >> > > _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
