2022-11-25 12:24:45

by Lee Jones

Subject: [PATCH v2 1/2] drm/amdgpu: Temporarily disable broken Clang builds due to blown stack-frame

calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
architectures built with Clang (all released versions), whereby the stack
frame gets blown up to well over 5k. This would cause an immediate kernel
panic on most architectures. We'll revert this when the following bug report
has been resolved: https://github.com/llvm/llvm-project/issues/41896.

Suggested-by: Arnd Bergmann <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
---
drivers/gpu/drm/amd/display/Kconfig | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
index 6925e0280dbe6..f4f3d2665a6b2 100644
--- a/drivers/gpu/drm/amd/display/Kconfig
+++ b/drivers/gpu/drm/amd/display/Kconfig
@@ -5,6 +5,7 @@ menu "Display Engine Configuration"
config DRM_AMD_DC
bool "AMD DC - Enable new display engine"
default y
+ depends on BROKEN || !CC_IS_CLANG || X86_64 || SPARC64 || ARM64
select SND_HDA_COMPONENT if SND_HDA_CORE
select DRM_AMD_DC_DCN if (X86 || PPC_LONG_DOUBLE_128)
help
@@ -12,6 +13,12 @@ config DRM_AMD_DC
support for AMDGPU. This adds required support for Vega and
Raven ASICs.

+ calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
+ architectures built with Clang (all released versions), whereby the stack
+ frame gets blown up to well over 5k. This would cause an immediate kernel
+ panic on most architectures. We'll revert this when the following bug report
+ has been resolved: https://github.com/llvm/llvm-project/issues/41896.
+
config DRM_AMD_DC_DCN
def_bool n
help
--
2.38.1.584.g0f3c55d4c2-goog

2022-11-25 12:50:56

by Arnd Bergmann

Subject: Re: [PATCH v2 1/2] drm/amdgpu: Temporarily disable broken Clang builds due to blown stack-frame

On Fri, Nov 25, 2022, at 13:07, Lee Jones wrote:
> calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
> architectures built with Clang (all released versions), whereby the stack
> frame gets blown up to well over 5k. This would cause an immediate kernel
> panic on most architectures. We'll revert this when the following bug report
> has been resolved: https://github.com/llvm/llvm-project/issues/41896.
>
> Suggested-by: Arnd Bergmann <[email protected]>
> Signed-off-by: Lee Jones <[email protected]>

Acked-by: Arnd Bergmann <[email protected]>

2022-11-28 06:19:48

by Nathan Chancellor

Subject: Re: [PATCH v2 1/2] drm/amdgpu: Temporarily disable broken Clang builds due to blown stack-frame

On Fri, Nov 25, 2022 at 12:07:49PM +0000, Lee Jones wrote:
> calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
> architectures built with Clang (all released versions), whereby the stack
> frame gets blown up to well over 5k. This would cause an immediate kernel
> panic on most architectures. We'll revert this when the following bug report
> has been resolved: https://github.com/llvm/llvm-project/issues/41896.
>
> Suggested-by: Arnd Bergmann <[email protected]>
> Signed-off-by: Lee Jones <[email protected]>

Reviewed-by: Nathan Chancellor <[email protected]>

> ---
> drivers/gpu/drm/amd/display/Kconfig | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
> index 6925e0280dbe6..f4f3d2665a6b2 100644
> --- a/drivers/gpu/drm/amd/display/Kconfig
> +++ b/drivers/gpu/drm/amd/display/Kconfig
> @@ -5,6 +5,7 @@ menu "Display Engine Configuration"
> config DRM_AMD_DC
> bool "AMD DC - Enable new display engine"
> default y
> + depends on BROKEN || !CC_IS_CLANG || X86_64 || SPARC64 || ARM64
> select SND_HDA_COMPONENT if SND_HDA_CORE
> select DRM_AMD_DC_DCN if (X86 || PPC_LONG_DOUBLE_128)
> help
> @@ -12,6 +13,12 @@ config DRM_AMD_DC
> support for AMDGPU. This adds required support for Vega and
> Raven ASICs.
>
> + calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
> + architectures built with Clang (all released versions), whereby the stack
> + frame gets blown up to well over 5k. This would cause an immediate kernel
> + panic on most architectures. We'll revert this when the following bug report
> + has been resolved: https://github.com/llvm/llvm-project/issues/41896.
> +
> config DRM_AMD_DC_DCN
> def_bool n
> help
> --
> 2.38.1.584.g0f3c55d4c2-goog
>