commit be68a8aaf925aaf35574260bf820bb09d2f9e07f upstream.
Our field definitions for CTR_EL0 suffer from a number of problems:
- The IDC and DIC fields are missing, which causes us to enable CTR trapping on CPUs with either of these returning non-zero values.
- The ERG is FTR_LOWER_SAFE, whereas it should be treated like CWG as FTR_HIGHER_SAFE so that applications can use it to avoid false sharing.
- [nit] A RES1 field is described as "RAO"
This patch updates the CTR_EL0 field definitions to fix these issues.
Cc: stable@vger.kernel.org # 4.4.y only Cc: Shanker Donthineni shankerd@codeaurora.org Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/kernel/cpufeature.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index c1eddc07d9968..fff0bf2f889e1 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -126,10 +126,12 @@ static struct arm64_ftr_bits ftr_id_aa64mmfr1[] = { };
static struct arm64_ftr_bits ftr_ctr[] = { - U_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RAO */ - ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 28, 3, 0), + U_ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */ + ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, 30, 1, 0), + U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 29, 1, 1), /* DIC */ + U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 28, 1, 1), /* IDC */ U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0), /* CWG */ - U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), /* ERG */ + U_ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, 20, 4, 0), /* ERG */ U_ARM64_FTR_BITS(FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1), /* DminLine */ /* * Linux can handle differing I-cache policies. Userspace JITs will