Hi Jeremy,
On 09/01/2019 23:55, Jeremy Linton wrote:
From: Mian Yousaf Kaukab <ykau...@suse.de>
Add is_meltdown_safe() which is a whitelist of known safe cores.
Signed-off-by: Mian Yousaf Kaukab <ykau...@suse.de>
[Moved location of function]
Signed-off-by: Jeremy Linton <jeremy.lin...@arm.com>
---
arch/arm64/kernel/cpufeature.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 4f272399de89..ab784d7a0083 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -947,8 +947,7 @@ has_useable_cnp(const struct arm64_cpu_capabilities *entry,
int scope)
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */
-static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
- int scope)
+static bool is_cpu_meltdown_safe(void)
{
/* List of CPUs that are not vulnerable and don't need KPTI */
static const struct midr_range kpti_safe_list[] = {
@@ -962,6 +961,15 @@ static bool unmap_kernel_at_el0(const struct
arm64_cpu_capabilities *entry,
MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
{ /* sentinel */ }
};
+ if (is_midr_in_range_list(read_cpuid_id(), kpti_safe_list))
nit: Does it make sense to rename the list to "meltdown_safe_list", to match the
function name ?
Also also, you may do :
return is_midr_in_range_list(read_cpuid_id(), kpti_safe_list);
Either way
Reviewed-by: Suzuki K Poulose <suzuki.poul...@arm.com>
