drivers/gpu/drm/i915/gvt/opregion.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
When a character array without a terminating NUL character has a static
initializer, GCC 15's -Wunterminated-string-initialization will only
warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
with __nonstring to and correctly identify the char array as "not a C
string" and thereby eliminate the warning.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.wang.linux@gmail.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tursulin@ursulin.net>
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: intel-gvt-dev@lists.freedesktop.org
Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Kees Cook <kees@kernel.org>
---
drivers/gpu/drm/i915/gvt/opregion.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
index 509f9ccae3a9..f701638d3145 100644
--- a/drivers/gpu/drm/i915/gvt/opregion.c
+++ b/drivers/gpu/drm/i915/gvt/opregion.c
@@ -43,7 +43,7 @@
#define DEVICE_TYPE_EFP4 0x10
struct opregion_header {
- u8 signature[16];
+ u8 signature[16] __nonstring;
u32 size;
u32 opregion_ver;
u8 bios_ver[32];
@@ -222,7 +222,7 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
u8 *buf;
struct opregion_header *header;
struct vbt v;
- const char opregion_signature[16] = OPREGION_SIGNATURE;
+ const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
--
2.34.1On 10.03.25 23:23, Kees Cook wrote: > When a character array without a terminating NUL character has a static > initializer, GCC 15's -Wunterminated-string-initialization will only > warn if the array lacks the "nonstring" attribute[1]. Mark the arrays > with __nonstring to and correctly identify the char array as "not a C > string" and thereby eliminate the warning. > > Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1] > [...] > Signed-off-by: Kees Cook <kees@kernel.org> To provide another small data point: Tested-by: Thorsten Leemhuis <linux@leemhuis.info> A "Compile-Tested-by", to be precise: after a handful similar patches reached mainline recently this is the only one I still need to compile the pretty broad Fedora rawhide config on rawhide using the GCC 15 pre-release it currently includes. The latter or the final will hopefully soon also reach Fedora 42 beta as well and bring the "[1]" mentioned in the patch description above to F42 -- which will be released in a few weeks, so I guess it would be nice to have this patch mainlined rather sooner that later to avoid more people running into this. HTH, ciao, Thorsten
On Mon, 31 Mar 2025, Thorsten Leemhuis <linux@leemhuis.info> wrote: > On 10.03.25 23:23, Kees Cook wrote: >> When a character array without a terminating NUL character has a static >> initializer, GCC 15's -Wunterminated-string-initialization will only >> warn if the array lacks the "nonstring" attribute[1]. Mark the arrays >> with __nonstring to and correctly identify the char array as "not a C >> string" and thereby eliminate the warning. >> >> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1] >> [...] >> Signed-off-by: Kees Cook <kees@kernel.org> > > To provide another small data point: > > Tested-by: Thorsten Leemhuis <linux@leemhuis.info> > > A "Compile-Tested-by", to be precise: after a handful similar patches > reached mainline recently this is the only one I still need to compile > the pretty broad Fedora rawhide config on rawhide using the GCC 15 > pre-release it currently includes. The latter or the final will > hopefully soon also reach Fedora 42 beta as well and bring the "[1]" > mentioned in the patch description above to F42 -- which will be > released in a few weeks, so I guess it would be nice to have this patch > mainlined rather sooner that later to avoid more people running into this. Thanks for testing, though I've merged [1] instead. BR, Jani. [1] https://lore.kernel.org/r/20250327124739.2609656-1-jani.nikula@intel.com -- Jani Nikula, Intel
On 01.04.25 10:46, Jani Nikula wrote: > On Mon, 31 Mar 2025, Thorsten Leemhuis <linux@leemhuis.info> wrote: >> On 10.03.25 23:23, Kees Cook wrote: >>> When a character array without a terminating NUL character has a static >>> initializer, GCC 15's -Wunterminated-string-initialization will only >>> warn if the array lacks the "nonstring" attribute[1]. Mark the arrays >>> with __nonstring to and correctly identify the char array as "not a C >>> string" and thereby eliminate the warning. >>> >>> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1] >>> [...] >>> Signed-off-by: Kees Cook <kees@kernel.org> >> >> To provide another small data point: >> >> Tested-by: Thorsten Leemhuis <linux@leemhuis.info> >> >> A "Compile-Tested-by", to be precise: after a handful similar patches >> reached mainline recently this is the only one I still need to compile >> the pretty broad Fedora rawhide config on rawhide using the GCC 15 >> pre-release it currently includes. The latter or the final will >> hopefully soon also reach Fedora 42 beta as well and bring the "[1]" >> mentioned in the patch description above to F42 -- which will be >> released in a few weeks, so I guess it would be nice to have this patch >> mainlined rather sooner that later to avoid more people running into this. > > Thanks for testing, though I've merged [1] instead. > > [1] https://lore.kernel.org/r/20250327124739.2609656-1-jani.nikula@intel.com Yeah, sorry, I only spotted that one two hours ago and started a test compile a while ago, but seems I'm too late here. Whatever, happens. :-D Many thx for taking care of that! Ciao, Thorsten
On Mon, 10. Mar 15:23, Kees Cook wrote:
> When a character array without a terminating NUL character has a static
> initializer, GCC 15's -Wunterminated-string-initialization will only
> warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
> with __nonstring to and correctly identify the char array as "not a C
> string" and thereby eliminate the warning.
>
> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
> Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
> Cc: Zhi Wang <zhi.wang.linux@gmail.com>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Tvrtko Ursulin <tursulin@ursulin.net>
> Cc: David Airlie <airlied@gmail.com>
> Cc: Simona Vetter <simona@ffwll.ch>
> Cc: intel-gvt-dev@lists.freedesktop.org
> Cc: intel-gfx@lists.freedesktop.org
> Cc: dri-devel@lists.freedesktop.org
> Signed-off-by: Kees Cook <kees@kernel.org>
> ---
> drivers/gpu/drm/i915/gvt/opregion.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> index 509f9ccae3a9..f701638d3145 100644
> --- a/drivers/gpu/drm/i915/gvt/opregion.c
> +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> @@ -43,7 +43,7 @@
> #define DEVICE_TYPE_EFP4 0x10
>
> struct opregion_header {
> - u8 signature[16];
> + u8 signature[16] __nonstring;
> u32 size;
> u32 opregion_ver;
> u8 bios_ver[32];
> @@ -222,7 +222,7 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> u8 *buf;
> struct opregion_header *header;
> struct vbt v;
> - const char opregion_signature[16] = OPREGION_SIGNATURE;
> + const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
>
> gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
> vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
> --
> 2.34.1
>
Hello together,
it doesnt resolve the build issue with gcc15 gcc (GCC) 15.0.1 20250228
CC [M] drivers/gpu/drm/i915/gvt/scheduler.o
/home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c: In function ‘intel_vgpu_init_opregion’:
/home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:35:28: error: initializer-string for array of ‘char’ is too long [-Werror=unterminated-string-initialization]
35 | #define OPREGION_SIGNATURE "IntelGraphicsMem"
| ^~~~~~~~~~~~~~~~~~
/home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:225:57: note: in expansion of macro ‘OPREGION_SIGNATURE’
225 | const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
| ^~~~~~~~~~~~~~~~~~
CC [M] drivers/gpu/drm/i915/gvt/trace_points.o
cc1: all warnings being treated as errors
make[7]: *** [/home/damian/kernel/linux/scripts/Makefile.build:207: drivers/gpu/drm/i915/gvt/opregion.o] Error 1
make[7]: *** Waiting for unfinished jobs....
CC [M] drivers/gpu/drm/i915/gvt/vgpu.o
make[6]: *** [/home/damian/kernel/linux/scripts/Makefile.build:465: drivers/gpu/drm/i915] Error 2
make[5]: *** [/home/damian/kernel/linux/s
--
VG
Damian Tometzki
On Sun, Mar 23, 2025 at 12:42:41PM +0000, Damian Tometzki wrote:
> On Mon, 10. Mar 15:23, Kees Cook wrote:
> > When a character array without a terminating NUL character has a static
> > initializer, GCC 15's -Wunterminated-string-initialization will only
> > warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
> > with __nonstring to and correctly identify the char array as "not a C
> > string" and thereby eliminate the warning.
> >
> > Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
> > Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
> > Cc: Zhi Wang <zhi.wang.linux@gmail.com>
> > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > Cc: Tvrtko Ursulin <tursulin@ursulin.net>
> > Cc: David Airlie <airlied@gmail.com>
> > Cc: Simona Vetter <simona@ffwll.ch>
> > Cc: intel-gvt-dev@lists.freedesktop.org
> > Cc: intel-gfx@lists.freedesktop.org
> > Cc: dri-devel@lists.freedesktop.org
> > Signed-off-by: Kees Cook <kees@kernel.org>
> > ---
> > drivers/gpu/drm/i915/gvt/opregion.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> > index 509f9ccae3a9..f701638d3145 100644
> > --- a/drivers/gpu/drm/i915/gvt/opregion.c
> > +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> > @@ -43,7 +43,7 @@
> > #define DEVICE_TYPE_EFP4 0x10
> >
> > struct opregion_header {
> > - u8 signature[16];
> > + u8 signature[16] __nonstring;
> > u32 size;
> > u32 opregion_ver;
> > u8 bios_ver[32];
> > @@ -222,7 +222,7 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> > u8 *buf;
> > struct opregion_header *header;
> > struct vbt v;
> > - const char opregion_signature[16] = OPREGION_SIGNATURE;
> > + const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
> >
> > gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
> > vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
> > --
> > 2.34.1
> >
> Hello together,
>
> it doesnt resolve the build issue with gcc15 gcc (GCC) 15.0.1 20250228
This was a recent enhancement to GCC, and that 20250228 build does not
include it. (GCC 15 is not actually released yet...)
--
Kees Cook
On Sun, 23 Mar 2025, Damian Tometzki <damian@riscv-rocks.de> wrote:
> On Mon, 10. Mar 15:23, Kees Cook wrote:
>> When a character array without a terminating NUL character has a static
>> initializer, GCC 15's -Wunterminated-string-initialization will only
>> warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
>> with __nonstring to and correctly identify the char array as "not a C
>> string" and thereby eliminate the warning.
>>
>> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
>> Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
>> Cc: Zhi Wang <zhi.wang.linux@gmail.com>
>> Cc: Jani Nikula <jani.nikula@linux.intel.com>
>> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
>> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
>> Cc: Tvrtko Ursulin <tursulin@ursulin.net>
>> Cc: David Airlie <airlied@gmail.com>
>> Cc: Simona Vetter <simona@ffwll.ch>
>> Cc: intel-gvt-dev@lists.freedesktop.org
>> Cc: intel-gfx@lists.freedesktop.org
>> Cc: dri-devel@lists.freedesktop.org
>> Signed-off-by: Kees Cook <kees@kernel.org>
>> ---
>> drivers/gpu/drm/i915/gvt/opregion.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
>> index 509f9ccae3a9..f701638d3145 100644
>> --- a/drivers/gpu/drm/i915/gvt/opregion.c
>> +++ b/drivers/gpu/drm/i915/gvt/opregion.c
>> @@ -43,7 +43,7 @@
>> #define DEVICE_TYPE_EFP4 0x10
>>
>> struct opregion_header {
>> - u8 signature[16];
>> + u8 signature[16] __nonstring;
Why would this annotation be needed? It's not treated as a string
anywhere, and it's u8 not char.
>> u32 size;
>> u32 opregion_ver;
>> u8 bios_ver[32];
>> @@ -222,7 +222,7 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
>> u8 *buf;
>> struct opregion_header *header;
>> struct vbt v;
>> - const char opregion_signature[16] = OPREGION_SIGNATURE;
>> + const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
>>
>> gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
>> vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
>> --
>> 2.34.1
>>
> Hello together,
>
> it doesnt resolve the build issue with gcc15 gcc (GCC) 15.0.1 20250228
>
> CC [M] drivers/gpu/drm/i915/gvt/scheduler.o
> /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c: In function ‘intel_vgpu_init_opregion’:
> /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:35:28: error: initializer-string for array of ‘char’ is too long [-Werror=unterminated-string-initialization]
> 35 | #define OPREGION_SIGNATURE "IntelGraphicsMem"
> | ^~~~~~~~~~~~~~~~~~
> /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:225:57: note: in expansion of macro ‘OPREGION_SIGNATURE’
> 225 | const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
> | ^~~~~~~~~~~~~~~~~~
> CC [M] drivers/gpu/drm/i915/gvt/trace_points.o
> cc1: all warnings being treated as errors
> make[7]: *** [/home/damian/kernel/linux/scripts/Makefile.build:207: drivers/gpu/drm/i915/gvt/opregion.o] Error 1
> make[7]: *** Waiting for unfinished jobs....
> CC [M] drivers/gpu/drm/i915/gvt/vgpu.o
> make[6]: *** [/home/damian/kernel/linux/scripts/Makefile.build:465: drivers/gpu/drm/i915] Error 2
> make[5]: *** [/home/damian/kernel/linux/s
What about this?
IMO it's anyway good practice to use sizeof(dest) rather than
sizeof(src) for memcpy.
diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
index 509f9ccae3a9..dbad4d853d3a 100644
--- a/drivers/gpu/drm/i915/gvt/opregion.c
+++ b/drivers/gpu/drm/i915/gvt/opregion.c
@@ -222,7 +222,6 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
u8 *buf;
struct opregion_header *header;
struct vbt v;
- const char opregion_signature[16] = OPREGION_SIGNATURE;
gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
@@ -236,8 +235,10 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
/* emulated opregion with VBT mailbox only */
buf = (u8 *)vgpu_opregion(vgpu)->va;
header = (struct opregion_header *)buf;
- memcpy(header->signature, opregion_signature,
- sizeof(opregion_signature));
+
+ static_assert(sizeof(header->signature) == sizeof(OPREGION_SIGNATURE) - 1);
+ memcpy(header->signature, OPREGION_SIGNATURE, sizeof(header->signature));
+
header->size = 0x8;
header->opregion_ver = 0x02000000;
header->mboxes = MBOX_VBT;
--
Jani Nikula, Intel
Le lun. 24 mars 2025 à 13:54, Jani Nikula
<jani.nikula@linux.intel.com> a écrit :
>
> On Sun, 23 Mar 2025, Damian Tometzki <damian@riscv-rocks.de> wrote:
> > On Mon, 10. Mar 15:23, Kees Cook wrote:
> >> When a character array without a terminating NUL character has a static
> >> initializer, GCC 15's -Wunterminated-string-initialization will only
> >> warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
> >> with __nonstring to and correctly identify the char array as "not a C
> >> string" and thereby eliminate the warning.
> >>
> >> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
> >> Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
> >> Cc: Zhi Wang <zhi.wang.linux@gmail.com>
> >> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> >> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> >> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> >> Cc: Tvrtko Ursulin <tursulin@ursulin.net>
> >> Cc: David Airlie <airlied@gmail.com>
> >> Cc: Simona Vetter <simona@ffwll.ch>
> >> Cc: intel-gvt-dev@lists.freedesktop.org
> >> Cc: intel-gfx@lists.freedesktop.org
> >> Cc: dri-devel@lists.freedesktop.org
> >> Signed-off-by: Kees Cook <kees@kernel.org>
> >> ---
> >> drivers/gpu/drm/i915/gvt/opregion.c | 4 ++--
> >> 1 file changed, 2 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> >> index 509f9ccae3a9..f701638d3145 100644
> >> --- a/drivers/gpu/drm/i915/gvt/opregion.c
> >> +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> >> @@ -43,7 +43,7 @@
> >> #define DEVICE_TYPE_EFP4 0x10
> >>
> >> struct opregion_header {
> >> - u8 signature[16];
> >> + u8 signature[16] __nonstring;
>
> Why would this annotation be needed? It's not treated as a string
> anywhere, and it's u8 not char.
>
> >> u32 size;
> >> u32 opregion_ver;
> >> u8 bios_ver[32];
> >> @@ -222,7 +222,7 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> >> u8 *buf;
> >> struct opregion_header *header;
> >> struct vbt v;
> >> - const char opregion_signature[16] = OPREGION_SIGNATURE;
> >> + const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
> >>
> >> gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
> >> vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
> >> --
> >> 2.34.1
> >>
> > Hello together,
> >
> > it doesnt resolve the build issue with gcc15 gcc (GCC) 15.0.1 20250228
> >
> > CC [M] drivers/gpu/drm/i915/gvt/scheduler.o
> > /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c: In function ‘intel_vgpu_init_opregion’:
> > /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:35:28: error: initializer-string for array of ‘char’ is too long [-Werror=unterminated-string-initialization]
> > 35 | #define OPREGION_SIGNATURE "IntelGraphicsMem"
> > | ^~~~~~~~~~~~~~~~~~
> > /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:225:57: note: in expansion of macro ‘OPREGION_SIGNATURE’
> > 225 | const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
> > | ^~~~~~~~~~~~~~~~~~
> > CC [M] drivers/gpu/drm/i915/gvt/trace_points.o
> > cc1: all warnings being treated as errors
> > make[7]: *** [/home/damian/kernel/linux/scripts/Makefile.build:207: drivers/gpu/drm/i915/gvt/opregion.o] Error 1
> > make[7]: *** Waiting for unfinished jobs....
> > CC [M] drivers/gpu/drm/i915/gvt/vgpu.o
> > make[6]: *** [/home/damian/kernel/linux/scripts/Makefile.build:465: drivers/gpu/drm/i915] Error 2
> > make[5]: *** [/home/damian/kernel/linux/s
>
> What about this?
>
> IMO it's anyway good practice to use sizeof(dest) rather than
> sizeof(src) for memcpy.
>
>
> diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> index 509f9ccae3a9..dbad4d853d3a 100644
> --- a/drivers/gpu/drm/i915/gvt/opregion.c
> +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> @@ -222,7 +222,6 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> u8 *buf;
> struct opregion_header *header;
> struct vbt v;
> - const char opregion_signature[16] = OPREGION_SIGNATURE;
>
> gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
> vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
> @@ -236,8 +235,10 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> /* emulated opregion with VBT mailbox only */
> buf = (u8 *)vgpu_opregion(vgpu)->va;
> header = (struct opregion_header *)buf;
> - memcpy(header->signature, opregion_signature,
> - sizeof(opregion_signature));
> +
> + static_assert(sizeof(header->signature) == sizeof(OPREGION_SIGNATURE) - 1);
> + memcpy(header->signature, OPREGION_SIGNATURE, sizeof(header->signature));
> +
> header->size = 0x8;
> header->opregion_ver = 0x02000000;
> header->mboxes = MBOX_VBT;
>
>
>
> --
> Jani Nikula, Intel
This patch does solve the build issue with gcc-15 on Fedora-42
(gcc-15.0.1-0.9.fc42.x86_64).
https://copr.fedorainfracloud.org/coprs/kwizart/kernel-longterm-6.12/build/8812754/
Thanks.
On Mon, 24. Mar 22:19, Nicolas Chauvet wrote:
> Le lun. 24 mars 2025 à 13:54, Jani Nikula
> <jani.nikula@linux.intel.com> a écrit :
> >
> > On Sun, 23 Mar 2025, Damian Tometzki <damian@riscv-rocks.de> wrote:
> > > On Mon, 10. Mar 15:23, Kees Cook wrote:
> > >> When a character array without a terminating NUL character has a static
> > >> initializer, GCC 15's -Wunterminated-string-initialization will only
> > >> warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
> > >> with __nonstring to and correctly identify the char array as "not a C
> > >> string" and thereby eliminate the warning.
> > >>
> > >> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
> > >> Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
> > >> Cc: Zhi Wang <zhi.wang.linux@gmail.com>
> > >> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > >> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> > >> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > >> Cc: Tvrtko Ursulin <tursulin@ursulin.net>
> > >> Cc: David Airlie <airlied@gmail.com>
> > >> Cc: Simona Vetter <simona@ffwll.ch>
> > >> Cc: intel-gvt-dev@lists.freedesktop.org
> > >> Cc: intel-gfx@lists.freedesktop.org
> > >> Cc: dri-devel@lists.freedesktop.org
> > >> Signed-off-by: Kees Cook <kees@kernel.org>
> > >> ---
> > >> drivers/gpu/drm/i915/gvt/opregion.c | 4 ++--
> > >> 1 file changed, 2 insertions(+), 2 deletions(-)
> > >>
> > >> diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> > >> index 509f9ccae3a9..f701638d3145 100644
> > >> --- a/drivers/gpu/drm/i915/gvt/opregion.c
> > >> +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> > >> @@ -43,7 +43,7 @@
> > >> #define DEVICE_TYPE_EFP4 0x10
> > >>
> > >> struct opregion_header {
> > >> - u8 signature[16];
> > >> + u8 signature[16] __nonstring;
> >
> > Why would this annotation be needed? It's not treated as a string
> > anywhere, and it's u8 not char.
> >
> > >> u32 size;
> > >> u32 opregion_ver;
> > >> u8 bios_ver[32];
> > >> @@ -222,7 +222,7 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> > >> u8 *buf;
> > >> struct opregion_header *header;
> > >> struct vbt v;
> > >> - const char opregion_signature[16] = OPREGION_SIGNATURE;
> > >> + const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
> > >>
> > >> gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
> > >> vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
> > >> --
> > >> 2.34.1
> > >>
> > > Hello together,
> > >
> > > it doesnt resolve the build issue with gcc15 gcc (GCC) 15.0.1 20250228
> > >
> > > CC [M] drivers/gpu/drm/i915/gvt/scheduler.o
> > > /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c: In function ‘intel_vgpu_init_opregion’:
> > > /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:35:28: error: initializer-string for array of ‘char’ is too long [-Werror=unterminated-string-initialization]
> > > 35 | #define OPREGION_SIGNATURE "IntelGraphicsMem"
> > > | ^~~~~~~~~~~~~~~~~~
> > > /home/damian/kernel/linux/drivers/gpu/drm/i915/gvt/opregion.c:225:57: note: in expansion of macro ‘OPREGION_SIGNATURE’
> > > 225 | const char opregion_signature[16] __nonstring = OPREGION_SIGNATURE;
> > > | ^~~~~~~~~~~~~~~~~~
> > > CC [M] drivers/gpu/drm/i915/gvt/trace_points.o
> > > cc1: all warnings being treated as errors
> > > make[7]: *** [/home/damian/kernel/linux/scripts/Makefile.build:207: drivers/gpu/drm/i915/gvt/opregion.o] Error 1
> > > make[7]: *** Waiting for unfinished jobs....
> > > CC [M] drivers/gpu/drm/i915/gvt/vgpu.o
> > > make[6]: *** [/home/damian/kernel/linux/scripts/Makefile.build:465: drivers/gpu/drm/i915] Error 2
> > > make[5]: *** [/home/damian/kernel/linux/s
> >
> > What about this?
> >
> > IMO it's anyway good practice to use sizeof(dest) rather than
> > sizeof(src) for memcpy.
> >
> >
> > diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c
> > index 509f9ccae3a9..dbad4d853d3a 100644
> > --- a/drivers/gpu/drm/i915/gvt/opregion.c
> > +++ b/drivers/gpu/drm/i915/gvt/opregion.c
> > @@ -222,7 +222,6 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> > u8 *buf;
> > struct opregion_header *header;
> > struct vbt v;
> > - const char opregion_signature[16] = OPREGION_SIGNATURE;
> >
> > gvt_dbg_core("init vgpu%d opregion\n", vgpu->id);
> > vgpu_opregion(vgpu)->va = (void *)__get_free_pages(GFP_KERNEL |
> > @@ -236,8 +235,10 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu)
> > /* emulated opregion with VBT mailbox only */
> > buf = (u8 *)vgpu_opregion(vgpu)->va;
> > header = (struct opregion_header *)buf;
> > - memcpy(header->signature, opregion_signature,
> > - sizeof(opregion_signature));
> > +
> > + static_assert(sizeof(header->signature) == sizeof(OPREGION_SIGNATURE) - 1);
> > + memcpy(header->signature, OPREGION_SIGNATURE, sizeof(header->signature));
> > +
> > header->size = 0x8;
> > header->opregion_ver = 0x02000000;
> > header->mboxes = MBOX_VBT;
> >
> >
> >
> > --
> > Jani Nikula, Intel
>
> This patch does solve the build issue with gcc-15 on Fedora-42
> (gcc-15.0.1-0.9.fc42.x86_64).
> https://copr.fedorainfracloud.org/coprs/kwizart/kernel-longterm-6.12/build/8812754/
testet-by Damian Tometzki
Thanks
Damian
>
> Thanks.
--
VG
Damian Tometzki
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