lkml.org 
[lkml]   [2019]   [Mar]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
Subject[PATCH v13 14/20] drm/amdgpu, arm64: untag user pointers in amdgpu_ttm_tt_get_user_pages
From
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.

amdgpu_ttm_tt_get_user_pages() uses provided user pointers for vma
lookups, which can only by done with untagged pointers.

Untag user pointers in this function.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 73e71e61dc99..891b027fa33b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -751,10 +751,11 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages)
* check that we only use anonymous memory to prevent problems
* with writeback
*/
- unsigned long end = gtt->userptr + ttm->num_pages * PAGE_SIZE;
+ unsigned long userptr = untagged_addr(gtt->userptr);
+ unsigned long end = userptr + ttm->num_pages * PAGE_SIZE;
struct vm_area_struct *vma;

- vma = find_vma(mm, gtt->userptr);
+ vma = find_vma(mm, userptr);
if (!vma || vma->vm_file || vma->vm_end < end) {
up_read(&mm->mmap_sem);
return -EPERM;
--
2.21.0.225.g810b269d1ac-goog
\
 
 \ /
  Last update: 2019-03-20 15:54    [W:0.161 / U:0.336 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site