X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=arch%2Farm64%2Fkernel%2Ftraps.c;fp=arch%2Farm64%2Fkernel%2Ftraps.c;h=93445f8b530c5e6f9d012ff0db1d96fa09093bde;hb=116c81f427ff6c5380850963e3fb8798cc821d2b;hp=224f64eddd93ad8ff97fb48ae60bbce69bc8d05f;hpb=9dbd5bb25c56e35e6b4c34d968689a1ded850924;p=cascardo%2Flinux.git

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 224f64eddd93..93445f8b530c 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -480,6 +480,14 @@ static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
 		regs->pc += 4;
 }
 
+static void ctr_read_handler(unsigned int esr, struct pt_regs *regs)
+{
+	int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT;
+
+	regs->regs[rt] = arm64_ftr_reg_ctrel0.sys_val;
+	regs->pc += 4;
+}
+
 struct sys64_hook {
 	unsigned int esr_mask;
 	unsigned int esr_val;
@@ -492,6 +500,12 @@ static struct sys64_hook sys64_hooks[] = {
 		.esr_val = ESR_ELx_SYS64_ISS_EL0_CACHE_OP_VAL,
 		.handler = user_cache_maint_handler,
 	},
+	{
+		/* Trap read access to CTR_EL0 */
+		.esr_mask = ESR_ELx_SYS64_ISS_SYS_OP_MASK,
+		.esr_val = ESR_ELx_SYS64_ISS_SYS_CTR_READ,
+		.handler = ctr_read_handler,
+	},
 	{},
 };