[PATCH v3 4/8] powerpc/pseries/svm: Add a powerpc version of cc_platform_has()

[Christophe Leroy]

Le 14/09/2021 à 13:58, Borislav Petkov a écrit :
> On Wed, Sep 08, 2021 at 05:58:35PM -0500, Tom Lendacky wrote:
>> Introduce a powerpc version of the cc_platform_has() function. This will
>> be used to replace the powerpc mem_encrypt_active() implementation, so
>> the implementation will initially only support the CC_ATTR_MEM_ENCRYPT
>> attribute.
>>
>> Cc: Michael Ellerman <mpe at ellerman.id.au>
>> Cc: Benjamin Herrenschmidt <benh at kernel.crashing.org>
>> Cc: Paul Mackerras <paulus at samba.org>
>> Signed-off-by: Tom Lendacky <thomas.lendacky at amd.com>
>> ---
>>   arch/powerpc/platforms/pseries/Kconfig       |  1 +
>>   arch/powerpc/platforms/pseries/Makefile      |  2 ++
>>   arch/powerpc/platforms/pseries/cc_platform.c | 26 ++++++++++++++++++++
>>   3 files changed, 29 insertions(+)
>>   create mode 100644 arch/powerpc/platforms/pseries/cc_platform.c
> 
> Michael,
> 
> can I get an ACK for the ppc bits to carry them through the tip tree
> pls?
> 
> Btw, on a related note, cross-compiling this throws the following error here:
> 
> $ make CROSS_COMPILE=/home/share/src/crosstool/gcc-9.4.0-nolibc/powerpc64-linux/bin/powerpc64-linux- V=1 ARCH=powerpc
> 
> ...
> 
> /home/share/src/crosstool/gcc-9.4.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc -Wp,-MD,arch/powerpc/boot/.crt0.o.d -D__ASSEMBLY__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -O2 -msoft-float -mno-altivec -mno-vsx -pipe -fomit-frame-pointer -fno-builtin -fPIC -nostdinc -include ./include/linux/compiler_attributes.h -I./arch/powerpc/include -I./arch/powerpc/include/generated  -I./include -I./arch/powerpc/include/uapi -I./arch/powerpc/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/compiler-version.h -include ./include/linux/kconfig.h -m32 -isystem /home/share/src/crosstool/gcc-9.4.0-nolibc/powerpc64-linux/bin/../lib/gcc/powerpc64-linux/9.4.0/include -mbig-endian -nostdinc -c -o arch/powerpc/boot/crt0.o arch/powerpc/boot/crt0.S
> In file included from <command-line>:
> ././include/linux/compiler_attributes.h:62:5: warning: "__has_attribute" is not defined, evaluates to 0 [-Wundef]
>     62 | #if __has_attribute(__assume_aligned__)
>        |     ^~~~~~~~~~~~~~~
> ././include/linux/compiler_attributes.h:62:20: error: missing binary operator before token "("
>     62 | #if __has_attribute(__assume_aligned__)
>        |                    ^
> ././include/linux/compiler_attributes.h:88:5: warning: "__has_attribute" is not defined, evaluates to 0 [-Wundef]
>     88 | #if __has_attribute(__copy__)
>        |     ^~~~~~~~~~~~~~~
> ...
> 
> Known issue?
> 
> This __has_attribute() thing is supposed to be supported
> in gcc since 5.1 and I'm using the crosstool stuff from
> https://www.kernel.org/pub/tools/crosstool/ and gcc-9.4 above is pretty
> new so that should not happen actually.
> 
> But it does...
> 
> Hmmm.
> 


Yes, see 
https://lore.kernel.org/linuxppc-dev/20210914123919.58203eef@canb.auug.org.au/T/#t