Commit 700b8860 authored by Reiji Watanabe's avatar Reiji Watanabe Committed by Marc Zyngier
Browse files

KVM: arm64: selftests: Remove the hard-coded {b,w}pn#0 from debug-exceptions 



Remove the hard-coded {break,watch}point #0 from the guest_code() in
debug-exceptions to allow {break,watch}point number to be specified.
Change reset_debug_state() to zeroing all dbg{b,w}{c,v}r_el0 registers
so that guest_code() can use the function to reset those registers
even when non-zero {break,watch}points are specified for guest_code().
Subsequent patches will add test cases for non-zero {break,watch}points.

Signed-off-by: default avatarReiji Watanabe <reijiw@google.com>
Reviewed-by: default avatarRicardo Koller <ricarkol@google.com>
Reviewed-by: default avatarOliver Upton <oliver.upton@linux.dev>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221020054202.2119018-4-reijiw@google.com
parent f6d02aa2

tools/testing/selftests/kvm/aarch64/debug-exceptions.c

+32 −18
Original line number Diff line number Diff line
@@ -95,6 +95,9 @@ GEN_DEBUG_WRITE_REG(dbgwvr) 


static void reset_debug_state(void)

{

	uint8_t brps, wrps, i;

	uint64_t dfr0;



	asm volatile("msr daifset, #8");



	write_sysreg(0, osdlr_el1);
@@ -102,11 +105,20 @@ static void reset_debug_state(void) 
	isb();



	write_sysreg(0, mdscr_el1);

	/* This test only uses the first bp and wp slot. */

	write_sysreg(0, dbgbvr0_el1);

	write_sysreg(0, dbgbcr0_el1);

	write_sysreg(0, dbgwcr0_el1);

	write_sysreg(0, dbgwvr0_el1);



	/* Reset all bcr/bvr/wcr/wvr registers */

	dfr0 = read_sysreg(id_aa64dfr0_el1);

	brps = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_BRPS), dfr0);

	for (i = 0; i <= brps; i++) {

		write_dbgbcr(i, 0);

		write_dbgbvr(i, 0);

	}

	wrps = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_WRPS), dfr0);

	for (i = 0; i <= wrps; i++) {

		write_dbgwcr(i, 0);

		write_dbgwvr(i, 0);

	}



	isb();

}
@@ -118,14 +130,14 @@ static void enable_os_lock(void) 
	GUEST_ASSERT(read_sysreg(oslsr_el1) & 2);

}



static void install_wp(uint64_t addr)

static void install_wp(uint8_t wpn, uint64_t addr)

{

	uint32_t wcr;

	uint32_t mdscr;



	wcr = DBGWCR_LEN8 | DBGWCR_RD | DBGWCR_WR | DBGWCR_EL1 | DBGWCR_E;

	write_dbgwcr(0, wcr);

	write_dbgwvr(0, addr);

	write_dbgwcr(wpn, wcr);

	write_dbgwvr(wpn, addr);



	isb();
@@ -136,14 +148,14 @@ static void install_wp(uint64_t addr) 
	isb();

}



static void install_hw_bp(uint64_t addr)

static void install_hw_bp(uint8_t bpn, uint64_t addr)

{

	uint32_t bcr;

	uint32_t mdscr;



	bcr = DBGBCR_LEN8 | DBGBCR_EXEC | DBGBCR_EL1 | DBGBCR_E;

	write_dbgbcr(0, bcr);

	write_dbgbvr(0, addr);

	write_dbgbcr(bpn, bcr);

	write_dbgbvr(bpn, addr);

	isb();



	asm volatile("msr daifclr, #8");
@@ -166,7 +178,7 @@ static void install_ss(void) 


static volatile char write_data;



static void guest_code(void)

static void guest_code(uint8_t bpn, uint8_t wpn)

{

	GUEST_SYNC(0);
@@ -179,7 +191,7 @@ static void guest_code(void) 


	/* Hardware-breakpoint */

	reset_debug_state();

	install_hw_bp(PC(hw_bp));

	install_hw_bp(bpn, PC(hw_bp));

	asm volatile("hw_bp: nop");

	GUEST_ASSERT_EQ(hw_bp_addr, PC(hw_bp));
@@ -187,7 +199,7 @@ static void guest_code(void) 


	/* Hardware-breakpoint + svc */

	reset_debug_state();

	install_hw_bp(PC(bp_svc));

	install_hw_bp(bpn, PC(bp_svc));

	asm volatile("bp_svc: svc #0");

	GUEST_ASSERT_EQ(hw_bp_addr, PC(bp_svc));

	GUEST_ASSERT_EQ(svc_addr, PC(bp_svc) + 4);
@@ -196,7 +208,7 @@ static void guest_code(void) 


	/* Hardware-breakpoint + software-breakpoint */

	reset_debug_state();

	install_hw_bp(PC(bp_brk));

	install_hw_bp(bpn, PC(bp_brk));

	asm volatile("bp_brk: brk #0");

	GUEST_ASSERT_EQ(sw_bp_addr, PC(bp_brk));

	GUEST_ASSERT_EQ(hw_bp_addr, PC(bp_brk));
@@ -205,7 +217,7 @@ static void guest_code(void) 


	/* Watchpoint */

	reset_debug_state();

	install_wp(PC(write_data));

	install_wp(wpn, PC(write_data));

	write_data = 'x';

	GUEST_ASSERT_EQ(write_data, 'x');

	GUEST_ASSERT_EQ(wp_data_addr, PC(write_data));
@@ -239,7 +251,7 @@ static void guest_code(void) 
	/* OS Lock blocking hardware-breakpoint */

	reset_debug_state();

	enable_os_lock();

	install_hw_bp(PC(hw_bp2));

	install_hw_bp(bpn, PC(hw_bp2));

	hw_bp_addr = 0;

	asm volatile("hw_bp2: nop");

	GUEST_ASSERT_EQ(hw_bp_addr, 0);
@@ -251,7 +263,7 @@ static void guest_code(void) 
	enable_os_lock();

	write_data = '\0';

	wp_data_addr = 0;

	install_wp(PC(write_data));

	install_wp(wpn, PC(write_data));

	write_data = 'x';

	GUEST_ASSERT_EQ(write_data, 'x');

	GUEST_ASSERT_EQ(wp_data_addr, 0);
@@ -376,6 +388,8 @@ static void test_guest_debug_exceptions(void) 
	vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,

				ESR_EC_SVC64, guest_svc_handler);



	/* Run tests with breakpoint#0 and watchpoint#0. */

	vcpu_args_set(vcpu, 2, 0, 0);

	for (stage = 0; stage < 11; stage++) {

		vcpu_run(vcpu);