Re: [PATCH] tools: testing: fix phys_addr_t size on 64-bit systems

From: Liam R. Howlett
Date: Thu Oct 17 2024 - 13:12:21 EST


* Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> [241017 12:56]:
> The phys_addr_t size is predicated on whether CONFIG_PHYS_ADDR_T_64BIT is
> set or not.
>
> In the VMA tests, virt_to_phys() from tools/include/linux casts a volatile
> void * pointer to phys_addr_t, if CONFIG_PHYS_ADDR_T_64BIT is not set, this
> will be 32-bit and trigger a warning.
>
> Obviously this might also lead to truncation, which we would rather avoid.
>
> Fix this by adjusting the generation of generated/bit-length.h to generate
> a CONFIG_PHYS_ADDR_T{bits}BIT define.
>
> This does result in the generation of the useless CONFIG_PHYS_ADDR_T_32BIT
> define for 32-bit systems, but this should have no effect, and makes
> implementation of this easier.
>
> This resolves the issue and the warning.
>
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>

Thanks, I just saw this, but your change fixes the vma test code for me.

Tested-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>

(both tags since I don't see the double tag in the submitting-patches
doc)

> ---
> tools/testing/shared/shared.mk | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/tools/testing/shared/shared.mk b/tools/testing/shared/shared.mk
> index a6bc51d0b0bf..b37362224a73 100644
> --- a/tools/testing/shared/shared.mk
> +++ b/tools/testing/shared/shared.mk
> @@ -69,6 +69,7 @@ generated/bit-length.h: FORCE
> @if ! grep -qws CONFIG_$(LONG_BIT)BIT generated/bit-length.h; then \
> echo "Generating $@"; \
> echo "#define CONFIG_$(LONG_BIT)BIT 1" > $@; \
> + echo "#define CONFIG_PHYS_ADDR_T_$(LONG_BIT)BIT 1" > $@; \
> fi
>
> FORCE: ;
> --
> 2.46.2
>