On 2019-04-30 9:25 a.m., Andrey Konovalov wrote: > [CAUTION: External Email] > > This patch is a part of a series that extends arm64 kernel ABI to allow to > pass tagged user pointers (with the top byte set to something else other > than 0x00) as syscall arguments. > > radeon_ttm_tt_pin_userptr() uses provided user pointers for vma > lookups, which can only by done with untagged pointers. This patch > untags user pointers when they are being set in > radeon_ttm_tt_pin_userptr(). > > In amdgpu_gem_userptr_ioctl() an MMU notifier is set up with a (tagged) > userspace pointer. The untagged address should be used so that MMU > notifiers for the untagged address get correctly matched up with the right > BO. This patch untags user pointers in radeon_gem_userptr_ioctl(). > > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > --- > drivers/gpu/drm/radeon/radeon_gem.c | 2 ++ > drivers/gpu/drm/radeon/radeon_ttm.c | 2 +- > 2 files changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c > index 44617dec8183..90eb78fb5eb2 100644 > --- a/drivers/gpu/drm/radeon/radeon_gem.c > +++ b/drivers/gpu/drm/radeon/radeon_gem.c > @@ -291,6 +291,8 @@ int radeon_gem_userptr_ioctl(struct drm_device *dev, void *data, > uint32_t handle; > int r; > > + args->addr = untagged_addr(args->addr); > + > if (offset_in_page(args->addr | args->size)) > return -EINVAL; > > diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c > index 9920a6fc11bf..dce722c494c1 100644 > --- a/drivers/gpu/drm/radeon/radeon_ttm.c > +++ b/drivers/gpu/drm/radeon/radeon_ttm.c > @@ -742,7 +742,7 @@ int radeon_ttm_tt_set_userptr(struct ttm_tt *ttm, uint64_t addr, > if (gtt == NULL) > return -EINVAL; > > - gtt->userptr = addr; > + gtt->userptr = untagged_addr(addr); Doing this here seems unnecessary, because you already untagged the address in the only caller of this function in radeon_gem_userptr_ioctl. The change there will affect both the userptr and MMU notifier setup and makes sure that both are in sync, using the same untagged address. Regards, Felix > gtt->usermm = current->mm; > gtt->userflags = flags; > return 0; > -- > 2.21.0.593.g511ec345e18-goog >
