4.15-stable review patch. If anyone has any objections, please let me know.
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From: Will Deacon will.deacon@arm.com
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 Cc: Shanker Donthineni shankerd@codeaurora.org Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm64/kernel/cpufeature.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -197,9 +197,11 @@ static const struct arm64_ftr_bits ftr_i };
static const struct arm64_ftr_bits ftr_ctr[] = { - ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RAO */ + ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */ + ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 29, 1, 1), /* DIC */ + ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 28, 1, 1), /* IDC */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, 24, 4, 0), /* CWG */ - ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0), /* ERG */ + ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, 20, 4, 0), /* ERG */ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 1), /* DminLine */ /* * Linux can handle differing I-cache policies. Userspace JITs will