Re: [PATCH] drm/amdgpu: Fix cat debugfs amdgpu_regs_didt causes kernel null pointer
Hi Lu,
kernel test robot noticed the following build errors:
[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on linus/master v6.7-rc2 next-20231124]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url:
https://github.com/intel-lab-lkp/linux/commits/Lu-Yao/drm-amdgpu-Fix-cat-debugfs-amdgpu_regs_didt-causes-kernel-null-pointer/20231122-203138
base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:
https://lore.kernel.org/r/20231122093509.34302-1-yaolu%40kylinos.cn
patch subject: [PATCH] drm/amdgpu: Fix cat debugfs amdgpu_regs_didt causes
kernel null pointer
config: x86_64-randconfig-001-20231123
(https://download.01.org/0day-ci/archive/20231124/202311241442.f0s4bazk-...@intel.com/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git
ae42196bc493ffe877a7e3dff8be32035dea4d07)
reproduce (this is a W=1 build):
(https://download.01.org/0day-ci/archive/20231124/202311241442.f0s4bazk-...@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot
| Closes:
https://lore.kernel.org/oe-kbuild-all/202311241442.f0s4bazk-...@intel.com/
All errors (new ones prefixed by >>):
warning: unknown warning option '-Wstringop-truncation'; did you mean
'-Wstring-concatenation'? [-Wunknown-warning-option]
warning: unknown warning option '-Wpacked-not-aligned'; did you mean
'-Wpacked-non-pod'? [-Wunknown-warning-option]
>> drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c:642:55: error: use of undeclared
>> identifier '__FUNC__'
dev_err(adev->dev, "%s adev->didt_rreg is null!\n",
__FUNC__);
^
drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c:703:55: error: use of undeclared
identifier '__FUNC__'
dev_err(adev->dev, "%s adev->didt_wreg is null!\n",
__FUNC__);
^
2 warnings and 2 errors generated.
vim +/__FUNC__ +642 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
618
619 /**
620 * amdgpu_debugfs_regs_didt_read - Read from a DIDT register
621 *
622 * @f: open file handle
623 * @buf: User buffer to store read data in
624 * @size: Number of bytes to read
625 * @pos: Offset to seek to
626 *
627 * The lower bits are the BYTE offset of the register to read. This
628 * allows reading multiple registers in a single call and having
629 * the returned size reflect that.
630 */
631 static ssize_t amdgpu_debugfs_regs_didt_read(struct file *f, char
__user *buf,
632 size_t size, loff_t *pos)
633 {
634 struct amdgpu_device *adev = file_inode(f)->i_private;
635 ssize_t result = 0;
636 int r;
637
638 if (size & 0x3 || *pos & 0x3)
639 return -EINVAL;
640
641 if (adev->didt_rreg == NULL) {
> 642 dev_err(adev->dev, "%s adev->didt_rreg is null!\n",
> __FUNC__);
643 return -EPERM;
644 }
645
646 r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
647 if (r < 0) {
648 pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
649 return r;
650 }
651
652 r = amdgpu_virt_enable_access_debugfs(adev);
653 if (r < 0) {
654 pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
655 return r;
656 }
657
658 while (size) {
659 uint32_t value;
660
661 value = RREG32_DIDT(*pos >> 2);
662 r = put_user(value, (uint32_t *)buf);
663 if (r)
664 goto out;
665
666 result += 4;
667 buf += 4;
668 *pos += 4;
669 size -= 4;
670 }
671
672 r = result;
673 out:
674 pm_runtime_mark_last_busy(adev_to_drm(adev)->dev);
675 pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
676 amdgpu_virt_disable_access_debugfs(adev);
677 return r;
678 }
679
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
[PATCH] drm/amdgpu: Fix cat debugfs amdgpu_regs_didt causes kernel null pointer
For 'AMDGPU_FAMILY_SI' family cards, in 'si_common_early_init' func, init
'didt_rreg' and 'didt_wreg' to 'NULL'. But in func
'amdgpu_debugfs_regs_didt_read/write', using 'RREG32_DIDT' 'WREG32_DIDT'
lacks of relevant judgment. And other 'amdgpu_ip_block_version' that use
these two definitions won't be added for 'AMDGPU_FAMILY_SI'.
So, add null pointer judgment before calling.
Signed-off-by: Lu Yao
---
drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 10 ++
1 file changed, 10 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index a53f436fa9f1..797d7d3bfd50 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -638,6 +638,11 @@ static ssize_t amdgpu_debugfs_regs_didt_read(struct file
*f, char __user *buf,
if (size & 0x3 || *pos & 0x3)
return -EINVAL;
+ if (adev->didt_rreg == NULL) {
+ dev_err(adev->dev, "%s adev->didt_rreg is null!\n", __FUNC__);
+ return -EPERM;
+ }
+
r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
if (r < 0) {
pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
@@ -694,6 +699,11 @@ static ssize_t amdgpu_debugfs_regs_didt_write(struct file
*f, const char __user
if (size & 0x3 || *pos & 0x3)
return -EINVAL;
+ if (adev->didt_wreg == NULL) {
+ dev_err(adev->dev, "%s adev->didt_wreg is null!\n", __FUNC__);
+ return -EPERM;
+ }
+
r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
if (r < 0) {
pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
--
2.25.1
Re: [PATCH] drm/amdgpu: Fix cat debugfs amdgpu_regs_didt causes kernel null pointer
Am 22.11.23 um 10:35 schrieb Lu Yao:
For 'AMDGPU_FAMILY_SI' family cards, in 'si_common_early_init' func, init
'didt_rreg' and 'didt_wreg' to 'NULL'. But in func
'amdgpu_debugfs_regs_didt_read/write', using 'RREG32_DIDT' 'WREG32_DIDT'
lacks of relevant judgment. And other 'amdgpu_ip_block_version' that use
these two definitions won't be added for 'AMDGPU_FAMILY_SI'.
So, add null pointer judgment before calling.
Signed-off-by: Lu Yao
---
drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 10 ++
1 file changed, 10 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index a53f436fa9f1..797d7d3bfd50 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -638,6 +638,11 @@ static ssize_t amdgpu_debugfs_regs_didt_read(struct file
*f, char __user *buf,
if (size & 0x3 || *pos & 0x3)
return -EINVAL;
+ if (adev->didt_rreg == NULL) {
+ dev_err(adev->dev, "%s adev->didt_rreg is null!\n", __FUNC__);
Please drop the dev_err(), this is not a device error but rather
userspace using a functionality not applicable for this device type.
+ return -EPERM;
Maybe rather use EOPNOTSUPP here.
Regards,
Christian.
+ }
+
r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
if (r < 0) {
pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
@@ -694,6 +699,11 @@ static ssize_t amdgpu_debugfs_regs_didt_write(struct file
*f, const char __user
if (size & 0x3 || *pos & 0x3)
return -EINVAL;
+ if (adev->didt_wreg == NULL) {
+ dev_err(adev->dev, "%s adev->didt_wreg is null!\n", __FUNC__);
+ return -EPERM;
+ }
+
r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
if (r < 0) {
pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
