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LoongArch: Enable generic CPU vulnerabilites support

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Currently, many architectures support generic CPU vulnerabilites, such
as x86, arm64 and riscv:

 commit 61dc0f555b ("x86/cpu: Implement CPU vulnerabilites sysfs functions")
 commit 61ae1321f0 ("arm64: enable generic CPU vulnerabilites support")
 commit 0e3f3649d4 ("riscv: Enable generic CPU vulnerabilites support")

All LoongArch CPUs (since Loongson-3A5000) implement a special mechanism
in the processor core to prevent "Meltdown" and "Spectre" attacks, so it
can enable generic CPU vulnerabilites support for LoongArch too.

Without this patch, there are no user interfaces of vulnerabilities to
check on LoongArch. The output of those files reflects the state of the
CPUs in the system, the output value "Not affected" means "CPU is not
affected by the vulnerability".

Before:

 # cat /sys/devices/system/cpu/vulnerabilities/spec_rstack_overflow
 cat: /sys/devices/system/cpu/vulnerabilities/spec_rstack_overflow: No such file or directory
 # cat /sys/devices/system/cpu/vulnerabilities/spec_store_bypass
 cat: /sys/devices/system/cpu/vulnerabilities/spec_store_bypass: No such file or directory
 # cat /sys/devices/system/cpu/vulnerabilities/meltdown
 cat: /sys/devices/system/cpu/vulnerabilities/meltdown: No such file or directory

After:

 # cat /sys/devices/system/cpu/vulnerabilities/spec_rstack_overflow
 Not affected
 # cat /sys/devices/system/cpu/vulnerabilities/spec_store_bypass
 Not affected
 # cat /sys/devices/system/cpu/vulnerabilities/meltdown
 Not affected

Link: https://www.loongson.cn/EN/news/show?id=633
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
This commit is contained in:
Tiezhu Yang 2024-09-24 15:31:51 +08:00 committed by Huacai Chen
parent 0eb0bd21e8
commit e8dd556c74
1 changed files with 1 additions and 0 deletions
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1
arch/loongarch/Kconfig
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@ -82,6 +82,7 @@ config LOONGARCH
select GENERIC_CMOS_UPDATE select GENERIC_CMOS_UPDATE
select GENERIC_CPU_AUTOPROBE select GENERIC_CPU_AUTOPROBE
select GENERIC_CPU_DEVICES select GENERIC_CPU_DEVICES
select GENERIC_CPU_VULNERABILITIES
select GENERIC_ENTRY select GENERIC_ENTRY
select GENERIC_GETTIMEOFDAY select GENERIC_GETTIMEOFDAY
select GENERIC_IOREMAP if !ARCH_IOREMAP select GENERIC_IOREMAP if !ARCH_IOREMAP