[v18,09/15] drm/amdgpu: untag user pointers

Submitted by Andrey Konovalov on June 24, 2019, 2:32 p.m.

Details

Message ID 1d036fc5bec4be059ee7f4f42bf7417dc44651dd.1561386715.git.andreyknvl@google.com
State New
Headers show
Series "arm64: untag user pointers passed to the kernel" ( rev: 9 8 ) in AMD X.Org drivers

Not browsing as part of any series.

Commit Message

Andrey Konovalov June 24, 2019, 2:32 p.m.
This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.

In amdgpu_gem_userptr_ioctl() and amdgpu_amdkfd_gpuvm.c/init_user_pages()
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 untag user pointers in
amdgpu_gem_userptr_ioctl() for the GEM case and in amdgpu_amdkfd_gpuvm_
alloc_memory_of_gpu() for the KFD case. This also makes sure that an
untagged pointer is passed to amdgpu_ttm_tt_get_user_pages(), which uses
it for vma lookups.

Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 2 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c          | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index a6e5184d436c..5d476e9bbc43 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -1108,7 +1108,7 @@  int amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu(
 		alloc_flags = 0;
 		if (!offset || !*offset)
 			return -EINVAL;
-		user_addr = *offset;
+		user_addr = untagged_addr(*offset);
 	} else if (flags & ALLOC_MEM_FLAGS_DOORBELL) {
 		domain = AMDGPU_GEM_DOMAIN_GTT;
 		alloc_domain = AMDGPU_GEM_DOMAIN_CPU;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index d4fcf5475464..e91df1407618 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -287,6 +287,8 @@  int amdgpu_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;
 

Comments

On Mon, Jun 24, 2019 at 04:32:54PM +0200, Andrey Konovalov wrote:
> This patch is a part of a series that extends kernel ABI to allow to pass
> tagged user pointers (with the top byte set to something else other than
> 0x00) as syscall arguments.
> 
> In amdgpu_gem_userptr_ioctl() and amdgpu_amdkfd_gpuvm.c/init_user_pages()
> 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 untag user pointers in
> amdgpu_gem_userptr_ioctl() for the GEM case and in amdgpu_amdkfd_gpuvm_
> alloc_memory_of_gpu() for the KFD case. This also makes sure that an
> untagged pointer is passed to amdgpu_ttm_tt_get_user_pages(), which uses
> it for vma lookups.
> 
> Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com>
> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 2 +-
>  drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c          | 2 ++
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> index a6e5184d436c..5d476e9bbc43 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> @@ -1108,7 +1108,7 @@ int amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu(
>  		alloc_flags = 0;
>  		if (!offset || !*offset)
>  			return -EINVAL;
> -		user_addr = *offset;
> +		user_addr = untagged_addr(*offset);
>  	} else if (flags & ALLOC_MEM_FLAGS_DOORBELL) {
>  		domain = AMDGPU_GEM_DOMAIN_GTT;
>  		alloc_domain = AMDGPU_GEM_DOMAIN_CPU;
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> index d4fcf5475464..e91df1407618 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> @@ -287,6 +287,8 @@ int amdgpu_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;
>  
> -- 
> 2.22.0.410.gd8fdbe21b5-goog
>