[PATCH v4 16/17] arm64: Add handling of CNTVCTSS traps

Marc Zyngier
2021-10-17T12:46:50Z

Since CNTVCTSS obey the same control bits as CNTVCT, add the necessary
decoding to the hook table. Note that there is no known user of
this at the moment.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/include/asm/esr.h | 6 ++++++
arch/arm64/kernel/traps.c | 11 +++++++++++
2 files changed, 17 insertions(+)

diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h
index 29f97eb3dad4..a305ce256090 100644
--- a/arch/arm64/include/asm/esr.h
+++ b/arch/arm64/include/asm/esr.h
@@ -227,6 +227,9 @@
#define ESR_ELx_SYS64_ISS_SYS_CNTVCT (ESR_ELx_SYS64_ISS_SYS_VAL(3, 3, 2, 14, 0) | \
ESR_ELx_SYS64_ISS_DIR_READ)

+#define ESR_ELx_SYS64_ISS_SYS_CNTVCTSS (ESR_ELx_SYS64_ISS_SYS_VAL(3, 3, 6, 14, 0) | \
+ ESR_ELx_SYS64_ISS_DIR_READ)
+
#define ESR_ELx_SYS64_ISS_SYS_CNTFRQ (ESR_ELx_SYS64_ISS_SYS_VAL(3, 3, 0, 14, 0) | \
ESR_ELx_SYS64_ISS_DIR_READ)

@@ -317,6 +320,9 @@
#define ESR_ELx_CP15_64_ISS_SYS_CNTVCT (ESR_ELx_CP15_64_ISS_SYS_VAL(1, 14) | \
ESR_ELx_CP15_64_ISS_DIR_READ)

+#define ESR_ELx_CP15_64_ISS_SYS_CNTVCTSS (ESR_ELx_CP15_64_ISS_SYS_VAL(9, 14) | \
+ ESR_ELx_CP15_64_ISS_DIR_READ)
+
#define ESR_ELx_CP15_32_ISS_SYS_CNTFRQ (ESR_ELx_CP15_32_ISS_SYS_VAL(0, 0, 14, 0) |\
ESR_ELx_CP15_32_ISS_DIR_READ)

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index b03e383d944a..16710ca55fbb 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -653,6 +653,12 @@ static const struct sys64_hook sys64_hooks[] = {
.esr_val = ESR_ELx_SYS64_ISS_SYS_CNTVCT,
.handler = cntvct_read_handler,
},
+ {
+ /* Trap read access to CNTVCTSS_EL0 */
+ .esr_mask = ESR_ELx_SYS64_ISS_SYS_OP_MASK,
+ .esr_val = ESR_ELx_SYS64_ISS_SYS_CNTVCTSS,
+ .handler = cntvct_read_handler,
+ },
{
/* Trap read access to CNTFRQ_EL0 */
.esr_mask = ESR_ELx_SYS64_ISS_SYS_OP_MASK,
@@ -729,6 +735,11 @@ static const struct sys64_hook cp15_64_hooks[] = {
.esr_val = ESR_ELx_CP15_64_ISS_SYS_CNTVCT,
.handler = compat_cntvct_read_handler,
},
+ {
+ .esr_mask = ESR_ELx_CP15_64_ISS_SYS_MASK,
+ .esr_val = ESR_ELx_CP15_64_ISS_SYS_CNTVCTSS,
+ .handler = compat_cntvct_read_handler,
+ },
{},
};

--
2.30.2