Merge branch kvm-arm64/coresight-6.14 into kvmarm-master/next

* kvm-arm64/coresight-6.14:
  : .
  : Trace filtering update from James Clark. From the cover letter:
  :
  : "The guest filtering rules from the Perf session are now honored for both
  : nVHE and VHE modes. This is done by either writing to TRFCR_EL12 at the
  : start of the Perf session and doing nothing else further, or caching the
  : guest value and writing it at guest switch for nVHE. In pKVM, trace is
  : now be disabled for both protected and unprotected guests."
  : .
  KVM: arm64: Fix selftests after sysreg field name update
  coresight: Pass guest TRFCR value to KVM
  KVM: arm64: Support trace filtering for guests
  KVM: arm64: coresight: Give TRBE enabled state to KVM
  coresight: trbe: Remove redundant disable call
  arm64/sysreg/tools: Move TRFCR definitions to sysreg
  tools: arm64: Update sysreg.h header files

Signed-off-by: Marc Zyngier <[email protected]>

Author: Marc Zyngier

arch/arm64/include/asm/kvm_host.h

@@ -617,6 +617,8 @@ struct kvm_host_data {
 #define KVM_HOST_DATA_FLAG_HAS_TRBE			1
 #define KVM_HOST_DATA_FLAG_HOST_SVE_ENABLED		2
 #define KVM_HOST_DATA_FLAG_HOST_SME_ENABLED		3
+#define KVM_HOST_DATA_FLAG_TRBE_ENABLED			4
+#define KVM_HOST_DATA_FLAG_EL1_TRACING_CONFIGURED	5
 	unsigned long flags;
 
 	struct kvm_cpu_context host_ctxt;
@@ -662,6 +664,9 @@ struct kvm_host_data {
 		u64 mdcr_el2;
 	} host_debug_state;
 
+	/* Guest trace filter value */
+	u64 trfcr_while_in_guest;
+
 	/* Number of programmable event counters (PMCR_EL0.N) for this CPU */
 	unsigned int nr_event_counters;
 
@@ -1389,13 +1394,19 @@ static inline bool kvm_pmu_counter_deferred(struct perf_event_attr *attr)
 void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr);
 void kvm_clr_pmu_events(u64 clr);
 bool kvm_set_pmuserenr(u64 val);
+void kvm_enable_trbe(void);
+void kvm_disable_trbe(void);
+void kvm_tracing_set_el1_configuration(u64 trfcr_while_in_guest);
 #else
 static inline void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr) {}
 static inline void kvm_clr_pmu_events(u64 clr) {}
 static inline bool kvm_set_pmuserenr(u64 val)
 {
 	return false;
 }
+static inline void kvm_enable_trbe(void) {}
+static inline void kvm_disable_trbe(void) {}
+static inline void kvm_tracing_set_el1_configuration(u64 trfcr_while_in_guest) {}
 #endif
 
 void kvm_vcpu_load_vhe(struct kvm_vcpu *vcpu);

arch/arm64/include/asm/sysreg.h

@@ -283,8 +283,6 @@
 #define SYS_RGSR_EL1			sys_reg(3, 0, 1, 0, 5)
 #define SYS_GCR_EL1			sys_reg(3, 0, 1, 0, 6)
 
-#define SYS_TRFCR_EL1			sys_reg(3, 0, 1, 2, 1)
-
 #define SYS_TCR_EL1			sys_reg(3, 0, 2, 0, 2)
 
 #define SYS_APIAKEYLO_EL1		sys_reg(3, 0, 2, 1, 0)
@@ -523,7 +521,6 @@
 #define SYS_VTTBR_EL2			sys_reg(3, 4, 2, 1, 0)
 #define SYS_VTCR_EL2			sys_reg(3, 4, 2, 1, 2)
 
-#define SYS_TRFCR_EL2			sys_reg(3, 4, 1, 2, 1)
 #define SYS_VNCR_EL2			sys_reg(3, 4, 2, 2, 0)
 #define SYS_HAFGRTR_EL2			sys_reg(3, 4, 3, 1, 6)
 #define SYS_SPSR_EL2			sys_reg(3, 4, 4, 0, 0)
@@ -987,15 +984,6 @@
 /* Safe value for MPIDR_EL1: Bit31:RES1, Bit30:U:0, Bit24:MT:0 */
 #define SYS_MPIDR_SAFE_VAL	(BIT(31))
 
-#define TRFCR_ELx_TS_SHIFT		5
-#define TRFCR_ELx_TS_MASK		((0x3UL) << TRFCR_ELx_TS_SHIFT)
-#define TRFCR_ELx_TS_VIRTUAL		((0x1UL) << TRFCR_ELx_TS_SHIFT)
-#define TRFCR_ELx_TS_GUEST_PHYSICAL	((0x2UL) << TRFCR_ELx_TS_SHIFT)
-#define TRFCR_ELx_TS_PHYSICAL		((0x3UL) << TRFCR_ELx_TS_SHIFT)
-#define TRFCR_EL2_CX			BIT(3)
-#define TRFCR_ELx_ExTRE			BIT(1)
-#define TRFCR_ELx_E0TRE			BIT(0)
-
 /* GIC Hypervisor interface registers */
 /* ICH_MISR_EL2 bit definitions */
 #define ICH_MISR_EOI		(1 << 0)

arch/arm64/kvm/debug.c

@@ -81,9 +81,15 @@ void kvm_init_host_debug_data(void)
 	    !(read_sysreg_s(SYS_PMBIDR_EL1) & PMBIDR_EL1_P))
 		host_data_set_flag(HAS_SPE);
 
-	if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_TraceBuffer_SHIFT) &&
-	    !(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_EL1_P))
-		host_data_set_flag(HAS_TRBE);
+	if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_TraceFilt_SHIFT)) {
+		/* Force disable trace in protected mode in case of no TRBE */
+		if (is_protected_kvm_enabled())
+			host_data_set_flag(EL1_TRACING_CONFIGURED);
+
+		if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_TraceBuffer_SHIFT) &&
+		    !(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_EL1_P))
+			host_data_set_flag(HAS_TRBE);
+	}
 }
 
 /*
@@ -219,3 +225,41 @@ void kvm_debug_handle_oslar(struct kvm_vcpu *vcpu, u64 val)
 	kvm_arch_vcpu_load(vcpu, smp_processor_id());
 	preempt_enable();
 }
+
+void kvm_enable_trbe(void)
+{
+	if (has_vhe() || is_protected_kvm_enabled() ||
+	    WARN_ON_ONCE(preemptible()))
+		return;
+
+	host_data_set_flag(TRBE_ENABLED);
+}
+EXPORT_SYMBOL_GPL(kvm_enable_trbe);
+
+void kvm_disable_trbe(void)
+{
+	if (has_vhe() || is_protected_kvm_enabled() ||
+	    WARN_ON_ONCE(preemptible()))
+		return;
+
+	host_data_clear_flag(TRBE_ENABLED);
+}
+EXPORT_SYMBOL_GPL(kvm_disable_trbe);
+
+void kvm_tracing_set_el1_configuration(u64 trfcr_while_in_guest)
+{
+	if (is_protected_kvm_enabled() || WARN_ON_ONCE(preemptible()))
+		return;
+
+	if (has_vhe()) {
+		write_sysreg_s(trfcr_while_in_guest, SYS_TRFCR_EL12);
+		return;
+	}
+
+	*host_data_ptr(trfcr_while_in_guest) = trfcr_while_in_guest;
+	if (read_sysreg_s(SYS_TRFCR_EL1) != trfcr_while_in_guest)
+		host_data_set_flag(EL1_TRACING_CONFIGURED);
+	else
+		host_data_clear_flag(EL1_TRACING_CONFIGURED);
+}
+EXPORT_SYMBOL_GPL(kvm_tracing_set_el1_configuration);

arch/arm64/kvm/hyp/nvhe/debug-sr.c

@@ -51,42 +51,55 @@ static void __debug_restore_spe(u64 pmscr_el1)
 	write_sysreg_el1(pmscr_el1, SYS_PMSCR);
 }
 
-static void __debug_save_trace(u64 *trfcr_el1)
+static void __trace_do_switch(u64 *saved_trfcr, u64 new_trfcr)
 {
-	*trfcr_el1 = 0;
+	*saved_trfcr = read_sysreg_el1(SYS_TRFCR);
+	write_sysreg_el1(new_trfcr, SYS_TRFCR);
+}
 
-	/* Check if the TRBE is enabled */
-	if (!(read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_EL1_E))
-		return;
-	/*
-	 * Prohibit trace generation while we are in guest.
-	 * Since access to TRFCR_EL1 is trapped, the guest can't
-	 * modify the filtering set by the host.
-	 */
-	*trfcr_el1 = read_sysreg_el1(SYS_TRFCR);
-	write_sysreg_el1(0, SYS_TRFCR);
-	isb();
-	/* Drain the trace buffer to memory */
-	tsb_csync();
+static bool __trace_needs_drain(void)
+{
+	if (is_protected_kvm_enabled() && host_data_test_flag(HAS_TRBE))
+		return read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_EL1_E;
+
+	return host_data_test_flag(TRBE_ENABLED);
 }
 
-static void __debug_restore_trace(u64 trfcr_el1)
+static bool __trace_needs_switch(void)
 {
-	if (!trfcr_el1)
-		return;
+	return host_data_test_flag(TRBE_ENABLED) ||
+	       host_data_test_flag(EL1_TRACING_CONFIGURED);
+}
+
+static void __trace_switch_to_guest(void)
+{
+	/* Unsupported with TRBE so disable */
+	if (host_data_test_flag(TRBE_ENABLED))
+		*host_data_ptr(trfcr_while_in_guest) = 0;
+
+	__trace_do_switch(host_data_ptr(host_debug_state.trfcr_el1),
+			  *host_data_ptr(trfcr_while_in_guest));
 
-	/* Restore trace filter controls */
-	write_sysreg_el1(trfcr_el1, SYS_TRFCR);
+	if (__trace_needs_drain()) {
+		isb();
+		tsb_csync();
+	}
+}
+
+static void __trace_switch_to_host(void)
+{
+	__trace_do_switch(host_data_ptr(trfcr_while_in_guest),
+			  *host_data_ptr(host_debug_state.trfcr_el1));
 }
 
 void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
 {
 	/* Disable and flush SPE data generation */
 	if (host_data_test_flag(HAS_SPE))
 		__debug_save_spe(host_data_ptr(host_debug_state.pmscr_el1));
-	/* Disable and flush Self-Hosted Trace generation */
-	if (host_data_test_flag(HAS_TRBE))
-		__debug_save_trace(host_data_ptr(host_debug_state.trfcr_el1));
+
+	if (__trace_needs_switch())
+		__trace_switch_to_guest();
 }
 
 void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
@@ -98,8 +111,8 @@ void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
 {
 	if (host_data_test_flag(HAS_SPE))
 		__debug_restore_spe(*host_data_ptr(host_debug_state.pmscr_el1));
-	if (host_data_test_flag(HAS_TRBE))
-		__debug_restore_trace(*host_data_ptr(host_debug_state.trfcr_el1));
+	if (__trace_needs_switch())
+		__trace_switch_to_host();
 }
 
 void __debug_switch_to_host(struct kvm_vcpu *vcpu)

arch/arm64/tools/sysreg

@@ -1999,6 +1999,22 @@ Field	17:16	ZEN
 Res0	15:0
 EndSysreg
 
+SysregFields TRFCR_ELx
+Res0	63:7
+UnsignedEnum	6:5	TS
+	0b0001	VIRTUAL
+	0b0010	GUEST_PHYSICAL
+	0b0011	PHYSICAL
+EndEnum
+Res0	4:2
+Field	1	ExTRE
+Field	0	E0TRE
+EndSysregFields
+
+Sysreg	TRFCR_EL1	3	0	1	2	1
+Fields	TRFCR_ELx
+EndSysreg
+
 Sysreg	SMPRI_EL1	3	0	1	2	4
 Res0	63:4
 Field	3:0	PRIORITY
@@ -2548,6 +2564,22 @@ Field	1	ICIALLU
 Field	0	ICIALLUIS
 EndSysreg
 
+Sysreg TRFCR_EL2	3	4	1	2	1
+Res0	63:7
+UnsignedEnum	6:5	TS
+	0b0000	USE_TRFCR_EL1_TS
+	0b0001	VIRTUAL
+	0b0010	GUEST_PHYSICAL
+	0b0011	PHYSICAL
+EndEnum
+Res0	4
+Field	3	CX
+Res0	2
+Field	1	E2TRE
+Field	0	E0HTRE
+EndSysreg
+
+
 Sysreg HDFGRTR_EL2	3	4	3	1	4
 Field	63	PMBIDR_EL1
 Field	62	nPMSNEVFR_EL1
@@ -2958,6 +2990,10 @@ Sysreg	ZCR_EL12	3	5	1	2	0
 Mapping	ZCR_EL1
 EndSysreg
 
+Sysreg	TRFCR_EL12	3	5	1	2	1
+Fields	TRFCR_ELx
+EndSysreg
+
 Sysreg	SMCR_EL12	3	5	1	2	6
 Mapping	SMCR_EL1
 EndSysreg

drivers/hwtracing/coresight/coresight-etm4x-core.c

@@ -6,6 +6,7 @@
 #include <linux/acpi.h>
 #include <linux/bitops.h>
 #include <linux/kernel.h>
+#include <linux/kvm_host.h>
 #include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/types.h>
@@ -268,10 +269,28 @@ struct etm4_enable_arg {
  */
 static void etm4x_prohibit_trace(struct etmv4_drvdata *drvdata)
 {
+	u64 trfcr;
+
 	/* If the CPU doesn't support FEAT_TRF, nothing to do */
 	if (!drvdata->trfcr)
 		return;
-	cpu_prohibit_trace();
+
+	trfcr = drvdata->trfcr & ~(TRFCR_ELx_ExTRE | TRFCR_ELx_E0TRE);
+
+	write_trfcr(trfcr);
+	kvm_tracing_set_el1_configuration(trfcr);
+}
+
+static u64 etm4x_get_kern_user_filter(struct etmv4_drvdata *drvdata)
+{
+	u64 trfcr = drvdata->trfcr;
+
+	if (drvdata->config.mode & ETM_MODE_EXCL_KERN)
+		trfcr &= ~TRFCR_ELx_ExTRE;
+	if (drvdata->config.mode & ETM_MODE_EXCL_USER)
+		trfcr &= ~TRFCR_ELx_E0TRE;
+
+	return trfcr;
 }
 
 /*
@@ -286,18 +305,28 @@ static void etm4x_prohibit_trace(struct etmv4_drvdata *drvdata)
  */
 static void etm4x_allow_trace(struct etmv4_drvdata *drvdata)
 {
-	u64 trfcr = drvdata->trfcr;
+	u64 trfcr, guest_trfcr;
 
 	/* If the CPU doesn't support FEAT_TRF, nothing to do */
-	if (!trfcr)
+	if (!drvdata->trfcr)
 		return;
 
-	if (drvdata->config.mode & ETM_MODE_EXCL_KERN)
-		trfcr &= ~TRFCR_ELx_ExTRE;
-	if (drvdata->config.mode & ETM_MODE_EXCL_USER)
-		trfcr &= ~TRFCR_ELx_E0TRE;
+	if (drvdata->config.mode & ETM_MODE_EXCL_HOST)
+		trfcr = drvdata->trfcr & ~(TRFCR_ELx_ExTRE | TRFCR_ELx_E0TRE);
+	else
+		trfcr = etm4x_get_kern_user_filter(drvdata);
 
 	write_trfcr(trfcr);
+
+	/* Set filters for guests and pass to KVM */
+	if (drvdata->config.mode & ETM_MODE_EXCL_GUEST)
+		guest_trfcr = drvdata->trfcr & ~(TRFCR_ELx_ExTRE | TRFCR_ELx_E0TRE);
+	else
+		guest_trfcr = etm4x_get_kern_user_filter(drvdata);
+
+	/* TRFCR_EL1 doesn't have CX so mask it out. */
+	guest_trfcr &= ~TRFCR_EL2_CX;
+	kvm_tracing_set_el1_configuration(guest_trfcr);
 }
 
 #ifdef CONFIG_ETM4X_IMPDEF_FEATURE
@@ -655,6 +684,12 @@ static int etm4_parse_event_config(struct coresight_device *csdev,
 	if (attr->exclude_user)
 		config->mode = ETM_MODE_EXCL_USER;
 
+	if (attr->exclude_host)
+		config->mode |= ETM_MODE_EXCL_HOST;
+
+	if (attr->exclude_guest)
+		config->mode |= ETM_MODE_EXCL_GUEST;
+
 	/* Always start from the default config */
 	etm4_set_default_config(config);
 

drivers/hwtracing/coresight/coresight-etm4x.h

@@ -817,7 +817,7 @@ enum etm_impdef_type {
  * @s_ex_level: Secure ELs where tracing is supported.
  */
 struct etmv4_config {
-	u32				mode;
+	u64				mode;
 	u32				pe_sel;
 	u32				cfg;
 	u32				eventctrl0;

drivers/hwtracing/coresight/coresight-priv.h

@@ -42,6 +42,9 @@ extern const struct device_type coresight_dev_type[];
 
 #define ETM_MODE_EXCL_KERN	BIT(30)
 #define ETM_MODE_EXCL_USER	BIT(31)
+#define ETM_MODE_EXCL_HOST	BIT(32)
+#define ETM_MODE_EXCL_GUEST	BIT(33)
+
 struct cs_pair_attribute {
 	struct device_attribute attr;
 	u32 lo_off;

drivers/hwtracing/coresight/coresight-self-hosted-trace.h

@@ -21,13 +21,4 @@ static inline void write_trfcr(u64 val)
 	isb();
 }
 
-static inline u64 cpu_prohibit_trace(void)
-{
-	u64 trfcr = read_trfcr();
-
-	/* Prohibit tracing at EL0 & the kernel EL */
-	write_trfcr(trfcr & ~(TRFCR_ELx_ExTRE | TRFCR_ELx_E0TRE));
-	/* Return the original value of the TRFCR */
-	return trfcr;
-}
 #endif /*  __CORESIGHT_SELF_HOSTED_TRACE_H */