On 7/17/2018 7:47 PM, LEROY Christophe wrote:
> Diana Craciun <diana.crac...@nxp.com> a écrit :
>
>> The NXP PPC Book3E platforms are not vulnerable to meltdown and
>> Spectre v4, so make them PPC_BOOK3S_64 specific.
>>
>> Signed-off-by: Diana Craciun <diana.crac...@nxp.com>
>> ---
>> History:
>>
>> v2-->v3
>> - used the existing functions for spectre v1/v2
>>
>> arch/powerpc/Kconfig | 7 ++++++-
>> arch/powerpc/kernel/security.c | 2 ++
>> 2 files changed, 8 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 9f2b75f..116c953 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -165,7 +165,7 @@ config PPC
>> select GENERIC_CLOCKEVENTS_BROADCAST if SMP
>> select GENERIC_CMOS_UPDATE
>> select GENERIC_CPU_AUTOPROBE
>> - select GENERIC_CPU_VULNERABILITIES if PPC_BOOK3S_64
>> + select GENERIC_CPU_VULNERABILITIES if PPC_NOSPEC
> I don't understand. You say this patch is to make something specific
> to book3s64 specific, and you are creating a new config param that
> make things less specific
>
> Christophe
In order to enable the vulnerabilities reporting on NXP socs I need to
enable them for PPC_FSL_BOOK3E. So they will be enabled for both
PPC_FSL_BOOK3E and PPC_BOOK3S_64. This is the reason for adding the
Kconfig. However this will enable: spectre v1/v2 and meltdown. NXP socs
are not vulnerable to meltdown, so I made the meltdown reporting
PPC_BOOK3S_64 specific. I guess I can have the PPC_NOSPEC definition in
a separate patch to be more clear.
Diana
>
>> select GENERIC_IRQ_SHOW
>> select GENERIC_IRQ_SHOW_LEVEL
>> select GENERIC_SMP_IDLE_THREAD
>> @@ -240,6 +240,11 @@ config PPC
>> # Please keep this list sorted alphabetically.
>> #
>>
>> +config PPC_NOSPEC
>> + bool
>> + default y
>> + depends on PPC_BOOK3S_64 || PPC_FSL_BOOK3E
>> +
>> config GENERIC_CSUM
>> def_bool n
>>
>> diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
>> index 3a4e5c3..539c744 100644
>> --- a/arch/powerpc/kernel/security.c
>> +++ b/arch/powerpc/kernel/security.c
>> @@ -92,6 +92,7 @@ static __init int barrier_nospec_debugfs_init(void)
>> device_initcall(barrier_nospec_debugfs_init);
>> #endif /* CONFIG_DEBUG_FS */
>>
>> +#ifdef CONFIG_PPC_BOOK3S_64
>> ssize_t cpu_show_meltdown(struct device *dev, struct
>> device_attribute *attr, char *buf)
>> {
>> bool thread_priv;
>> @@ -124,6 +125,7 @@ ssize_t cpu_show_meltdown(struct device *dev,
>> struct device_attribute *attr, cha
>>
>> return sprintf(buf, "Vulnerable\n");
>> }
>> +#endif
>>
>> ssize_t cpu_show_spectre_v1(struct device *dev, struct
>> device_attribute *attr, char *buf)
>> {
>> --
>> 2.5.5
>
>
