Re: [PATCH 5/6] arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register

From: Suzuki K Poulose
Date: Fri Mar 20 2020 - 14:14:41 EST


On 01/28/2020 12:39 PM, Anshuman Khandual wrote:
ID_DFR0 based TraceFilt feature should not be exposed.

... to guests.

Hence lets drop it.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>


Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 2726bd6441da..a8ded1f0eeaf 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -374,7 +374,6 @@ static const struct arm64_ftr_bits ftr_id_pfr2[] = {
};
static const struct arm64_ftr_bits ftr_id_dfr0[] = {
- ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf), /* PerfMon */
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 20, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 16, 4, 0),