Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
On Tue, Sep 5, 2023 at 12:15 PM Francis, David wrote:
>
> [AMD Official Use Only - General]
>
>
> [AMD Official Use Only - General]
>
> Yeah we've had JIRAs (e.g.
> https://ontrack-internal.amd.com/browse/SWDEV-409711 ) raised that ASAN can't
> compile the thunk due to using = {0} . Using memset is definitely preferred
> to save trouble later.
>
> Kent
>
> This is kernel code, not thunk. {} and {0} are extensively used throughout
> the kernel in general and our driver in particular, so I don't see this
> causing problems.
Speaking for the kernel, we've seen problematic behavior when using {}
vs {0} vs memset. memset always seems to do the right thing, the
others don't. E.g., there was a series of patch sets to switch
everything from {} to {0} or vice versa, we just traded one issue for
another. For this patch, you can probably just drop that hunk as I
don't see a need to change it. Whether you switch to memset or not is
up to you.
Alex
>
> David
>
> -Original Message-
> From: amd-gfx On Behalf Of Alex
> Deucher
> Sent: Tuesday, September 5, 2023 10:53 AM
> To: Francis, David
> Cc: amd-gfx@lists.freedesktop.org
> Subject: Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
>
> On Tue, Sep 5, 2023 at 10:50 AM David Francis wrote:
>
> On some APU systems, there is no atom context and so the
> atom_context struct is null.
>
> Add a check to the VBIOS_INFO branch of amdgpu_info_ioctl
> to handle this case, returning all zeroes.
>
> Signed-off-by: David Francis
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 19 ---
> 1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>
> index 3a48bec10aea..86748290ead7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -947,16 +947,21 @@ int amdgpu_info_ioctl(struct drm_device *dev, void
>
> *data, struct drm_file *filp)
>
> ? -EFAULT : 0;
> }
> case AMDGPU_INFO_VBIOS_INFO: {
> - struct drm_amdgpu_info_vbios vbios_info = {};
> + struct drm_amdgpu_info_vbios vbios_info = {0};
>
> IIRC, these should be equivalent. That said, I believe memset is
> generally preferred as not all compilers seem to handle these cases
> correctly.
>
> Alex
>
> struct atom_context *atom_context;
>
> atom_context = adev->mode_info.atom_context;
> - memcpy(vbios_info.name, atom_context->name,
>
> sizeof(atom_context->name));
>
> - memcpy(vbios_info.vbios_pn, atom_context->vbios_pn,
>
> sizeof(atom_context->vbios_pn));
>
> - vbios_info.version = atom_context->version;
> - memcpy(vbios_info.vbios_ver_str,
> atom_context->vbios_ver_str,
> -
> sizeof(atom_context->vbios_ver_str));
> - memcpy(vbios_info.date, atom_context->date,
>
> sizeof(atom_context->date));
>
> + if (atom_context) {
> + memcpy(vbios_info.name, atom_context->name,
> + sizeof(atom_context->name));
> + memcpy(vbios_info.vbios_pn,
> atom_context->vbios_pn,
> + sizeof(atom_context->vbios_pn));
> + vbios_info.version = atom_context->version;
> + memcpy(vbios_info.vbios_ver_str, atom_context-
> vbios_ver_str,
> + sizeof(atom_context->vbios_ver_str));
> + memcpy(vbios_info.date, atom_context->date,
> + sizeof(atom_context->date));
> + }
>
> return copy_to_user(out, &vbios_info,
> min((size_t)size,
> sizeof(vbios_info))) ? -EFAULT : 0;
> --
> 2.34.1
>
RE: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
[AMD Official Use Only - General]
Sorry, meant to keep the JIRA part internal. As it stands, the amd/ folder
alone has 458 {0}s (plus 55 {}s), and 741 memset-to-0s. So I guess it’s a
matter of whether or not we’ll start enforcing memsets vs {0} in the near
future. If we intend to switch over soon anyways, we may as well start using
memset now and in all future patches.
Kent
From: Francis, David
Sent: Tuesday, September 5, 2023 11:38 AM
To: Russell, Kent ; amd-gfx@lists.freedesktop.org
Subject: Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
[AMD Official Use Only - General]
[AMD Official Use Only - General]
Yeah we've had JIRAs (e.g. https://ontrack-internal.amd.com/browse/SWDEV-409711
) raised that ASAN can't compile the thunk due to using = {0} . Using memset is
definitely preferred to save trouble later.
Kent
This is kernel code, not thunk. {} and {0} are extensively used throughout
the kernel in general and our driver in particular, so I don't see this causing
problems.
David
-Original Message-
From: amd-gfx
<mailto:amd-gfx-boun...@lists.freedesktop.org>
On Behalf Of Alex
Deucher
Sent: Tuesday, September 5, 2023 10:53 AM
To: Francis, David <mailto:david.fran...@amd.com>
Cc: amd-gfx@lists.freedesktop.org<mailto:amd-gfx@lists.freedesktop.org>
Subject: Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
On Tue, Sep 5, 2023 at 10:50 AM David Francis
<mailto:david.fran...@amd.com> wrote:
On some APU systems, there is no atom context and so the
atom_context struct is null.
Add a check to the VBIOS_INFO branch of amdgpu_info_ioctl
to handle this case, returning all zeroes.
Signed-off-by: David Francis
<mailto:david.fran...@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 19 ---
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index 3a48bec10aea..86748290ead7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -947,16 +947,21 @@ int amdgpu_info_ioctl(struct drm_device *dev, void
*data, struct drm_file *filp)
? -EFAULT : 0;
}
case AMDGPU_INFO_VBIOS_INFO: {
- struct drm_amdgpu_info_vbios vbios_info = {};
+ struct drm_amdgpu_info_vbios vbios_info = {0};
IIRC, these should be equivalent. That said, I believe memset is
generally preferred as not all compilers seem to handle these cases
correctly.
Alex
struct atom_context *atom_context;
atom_context = adev->mode_info.atom_context;
- memcpy(vbios_info.name, atom_context->name,
sizeof(atom_context->name));
- memcpy(vbios_info.vbios_pn, atom_context->vbios_pn,
sizeof(atom_context->vbios_pn));
- vbios_info.version = atom_context->version;
- memcpy(vbios_info.vbios_ver_str,
atom_context->vbios_ver_str,
-
sizeof(atom_context->vbios_ver_str));
- memcpy(vbios_info.date, atom_context->date,
sizeof(atom_context->date));
+ if (atom_context) {
+ memcpy(vbios_info.name, atom_context->name,
+ sizeof(atom_context->name));
+ memcpy(vbios_info.vbios_pn,
atom_context->vbios_pn,
+ sizeof(atom_context->vbios_pn));
+ vbios_info.version = atom_context->version;
+ memcpy(vbios_info.vbios_ver_str, atom_context-
vbios_ver_str,
+ sizeof(atom_context->vbios_ver_str));
+ memcpy(vbios_info.date, atom_context->date,
+ sizeof(atom_context->date));
+ }
return copy_to_user(out, &vbios_info,
min((size_t)size,
sizeof(vbios_info))) ? -EFAULT : 0;
--
2.34.1
Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
[AMD Official Use Only - General]
[AMD Official Use Only - General]
Yeah we've had JIRAs (e.g. https://ontrack-internal.amd.com/browse/SWDEV-409711
) raised that ASAN can't compile the thunk due to using = {0} . Using memset is
definitely preferred to save trouble later.
Kent
This is kernel code, not thunk. {} and {0} are extensively used throughout
the kernel in general and our driver in particular, so I don't see this causing
problems.
David
-Original Message-
From: amd-gfx
<mailto:amd-gfx-boun...@lists.freedesktop.org>
On Behalf Of Alex
Deucher
Sent: Tuesday, September 5, 2023 10:53 AM
To: Francis, David <mailto:david.fran...@amd.com>
Cc: amd-gfx@lists.freedesktop.org<mailto:amd-gfx@lists.freedesktop.org>
Subject: Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
On Tue, Sep 5, 2023 at 10:50 AM David Francis
<mailto:david.fran...@amd.com> wrote:
On some APU systems, there is no atom context and so the
atom_context struct is null.
Add a check to the VBIOS_INFO branch of amdgpu_info_ioctl
to handle this case, returning all zeroes.
Signed-off-by: David Francis
<mailto:david.fran...@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 19 ---
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index 3a48bec10aea..86748290ead7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -947,16 +947,21 @@ int amdgpu_info_ioctl(struct drm_device *dev, void
*data, struct drm_file *filp)
? -EFAULT : 0;
}
case AMDGPU_INFO_VBIOS_INFO: {
- struct drm_amdgpu_info_vbios vbios_info = {};
+ struct drm_amdgpu_info_vbios vbios_info = {0};
IIRC, these should be equivalent. That said, I believe memset is
generally preferred as not all compilers seem to handle these cases
correctly.
Alex
struct atom_context *atom_context;
atom_context = adev->mode_info.atom_context;
- memcpy(vbios_info.name, atom_context->name,
sizeof(atom_context->name));
- memcpy(vbios_info.vbios_pn, atom_context->vbios_pn,
sizeof(atom_context->vbios_pn));
- vbios_info.version = atom_context->version;
- memcpy(vbios_info.vbios_ver_str,
atom_context->vbios_ver_str,
-
sizeof(atom_context->vbios_ver_str));
- memcpy(vbios_info.date, atom_context->date,
sizeof(atom_context->date));
+ if (atom_context) {
+ memcpy(vbios_info.name, atom_context->name,
+ sizeof(atom_context->name));
+ memcpy(vbios_info.vbios_pn,
atom_context->vbios_pn,
+ sizeof(atom_context->vbios_pn));
+ vbios_info.version = atom_context->version;
+ memcpy(vbios_info.vbios_ver_str, atom_context-
vbios_ver_str,
+ sizeof(atom_context->vbios_ver_str));
+ memcpy(vbios_info.date, atom_context->date,
+ sizeof(atom_context->date));
+ }
return copy_to_user(out, &vbios_info,
min((size_t)size,
sizeof(vbios_info))) ? -EFAULT : 0;
--
2.34.1
Re: [PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
On Tue, Sep 5, 2023 at 10:50 AM David Francis wrote:
>
> On some APU systems, there is no atom context and so the
> atom_context struct is null.
>
> Add a check to the VBIOS_INFO branch of amdgpu_info_ioctl
> to handle this case, returning all zeroes.
>
> Signed-off-by: David Francis
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 19 ---
> 1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> index 3a48bec10aea..86748290ead7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -947,16 +947,21 @@ int amdgpu_info_ioctl(struct drm_device *dev, void
> *data, struct drm_file *filp)
> ? -EFAULT : 0;
> }
> case AMDGPU_INFO_VBIOS_INFO: {
> - struct drm_amdgpu_info_vbios vbios_info = {};
> + struct drm_amdgpu_info_vbios vbios_info = {0};
IIRC, these should be equivalent. That said, I believe memset is
generally preferred as not all compilers seem to handle these cases
correctly.
Alex
> struct atom_context *atom_context;
>
> atom_context = adev->mode_info.atom_context;
> - memcpy(vbios_info.name, atom_context->name,
> sizeof(atom_context->name));
> - memcpy(vbios_info.vbios_pn, atom_context->vbios_pn,
> sizeof(atom_context->vbios_pn));
> - vbios_info.version = atom_context->version;
> - memcpy(vbios_info.vbios_ver_str,
> atom_context->vbios_ver_str,
> -
> sizeof(atom_context->vbios_ver_str));
> - memcpy(vbios_info.date, atom_context->date,
> sizeof(atom_context->date));
> + if (atom_context) {
> + memcpy(vbios_info.name, atom_context->name,
> + sizeof(atom_context->name));
> + memcpy(vbios_info.vbios_pn,
> atom_context->vbios_pn,
> + sizeof(atom_context->vbios_pn));
> + vbios_info.version = atom_context->version;
> + memcpy(vbios_info.vbios_ver_str,
> atom_context->vbios_ver_str,
> + sizeof(atom_context->vbios_ver_str));
> + memcpy(vbios_info.date, atom_context->date,
> + sizeof(atom_context->date));
> + }
>
> return copy_to_user(out, &vbios_info,
> min((size_t)size,
> sizeof(vbios_info))) ? -EFAULT : 0;
> --
> 2.34.1
>
[PATCH] drm/amdgpu: Handle null atom context in VBIOS info ioctl
On some APU systems, there is no atom context and so the
atom_context struct is null.
Add a check to the VBIOS_INFO branch of amdgpu_info_ioctl
to handle this case, returning all zeroes.
Signed-off-by: David Francis
---
drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 19 ---
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index 3a48bec10aea..86748290ead7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -947,16 +947,21 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data,
struct drm_file *filp)
? -EFAULT : 0;
}
case AMDGPU_INFO_VBIOS_INFO: {
- struct drm_amdgpu_info_vbios vbios_info = {};
+ struct drm_amdgpu_info_vbios vbios_info = {0};
struct atom_context *atom_context;
atom_context = adev->mode_info.atom_context;
- memcpy(vbios_info.name, atom_context->name,
sizeof(atom_context->name));
- memcpy(vbios_info.vbios_pn, atom_context->vbios_pn,
sizeof(atom_context->vbios_pn));
- vbios_info.version = atom_context->version;
- memcpy(vbios_info.vbios_ver_str,
atom_context->vbios_ver_str,
-
sizeof(atom_context->vbios_ver_str));
- memcpy(vbios_info.date, atom_context->date,
sizeof(atom_context->date));
+ if (atom_context) {
+ memcpy(vbios_info.name, atom_context->name,
+ sizeof(atom_context->name));
+ memcpy(vbios_info.vbios_pn,
atom_context->vbios_pn,
+ sizeof(atom_context->vbios_pn));
+ vbios_info.version = atom_context->version;
+ memcpy(vbios_info.vbios_ver_str,
atom_context->vbios_ver_str,
+ sizeof(atom_context->vbios_ver_str));
+ memcpy(vbios_info.date, atom_context->date,
+ sizeof(atom_context->date));
+ }
return copy_to_user(out, &vbios_info,
min((size_t)size,
sizeof(vbios_info))) ? -EFAULT : 0;
--
2.34.1
