@@ -12,6 +12,10 @@
#define DBGBCR_EXEC (0x0 << 3)
#define DBGBCR_EL1 (0x1 << 1)
#define DBGBCR_E (0x1 << 0)
+#define DBGBCR_LBN_SHIFT 16
+#define DBGBCR_BT_SHIFT 20
+#define DBGBCR_BT_ADDR_LINK_CTX (0x1 << DBGBCR_BT_SHIFT)
+#define DBGBCR_BT_CTX_LINK (0x3 << DBGBCR_BT_SHIFT)
#define DBGWCR_LEN8 (0xff << 5)
#define DBGWCR_RD (0x1 << 3)
@@ -22,7 +26,7 @@
#define SPSR_D (1 << 9)
#define SPSR_SS (1 << 21)
-extern unsigned char sw_bp, sw_bp2, hw_bp, hw_bp2, bp_svc, bp_brk, hw_wp, ss_start;
+extern unsigned char sw_bp, sw_bp2, hw_bp, hw_bp2, bp_svc, bp_brk, hw_wp, ss_start, hw_bp_ctx;
extern unsigned char iter_ss_begin, iter_ss_end;
static volatile uint64_t sw_bp_addr, hw_bp_addr;
static volatile uint64_t wp_addr, wp_data_addr;
@@ -105,6 +109,7 @@ static void reset_debug_state(void)
isb();
write_sysreg(0, mdscr_el1);
+ write_sysreg(0, contextidr_el1);
/* Reset all bcr/bvr/wcr/wvr registers */
dfr0 = read_sysreg(id_aa64dfr0_el1);
@@ -166,6 +171,31 @@ static void install_hw_bp(uint8_t bpn, uint64_t addr)
enable_monitor_debug_exceptions();
}
+void install_hw_bp_ctx(uint8_t addr_bp, uint8_t ctx_bp, uint64_t addr,
+ uint64_t ctx)
+{
+ uint32_t addr_bcr, ctx_bcr;
+
+ /* Setup a context-aware breakpoint for Linked Context ID Match */
+ ctx_bcr = DBGBCR_LEN8 | DBGBCR_EXEC | DBGBCR_EL1 | DBGBCR_E |
+ DBGBCR_BT_CTX_LINK;
+ write_dbgbcr(ctx_bp, ctx_bcr);
+ write_dbgbvr(ctx_bp, ctx);
+
+ /*
+ * Setup a normal breakpoint for Linked Address Match, and link it
+ * to the context-aware breakpoint.
+ */
+ addr_bcr = DBGBCR_LEN8 | DBGBCR_EXEC | DBGBCR_EL1 | DBGBCR_E |
+ DBGBCR_BT_ADDR_LINK_CTX |
+ ((uint32_t)ctx_bp << DBGBCR_LBN_SHIFT);
+ write_dbgbcr(addr_bp, addr_bcr);
+ write_dbgbvr(addr_bp, addr);
+ isb();
+
+ enable_monitor_debug_exceptions();
+}
+
static void install_ss(void)
{
uint32_t mdscr;
@@ -179,8 +209,10 @@ static void install_ss(void)
static volatile char write_data;
-static void guest_code(uint8_t bpn, uint8_t wpn)
+static void guest_code(uint8_t bpn, uint8_t wpn, uint8_t ctx_bpn)
{
+ uint64_t ctx = 0xabcdef; /* a random context number */
+
/* Software-breakpoint */
reset_debug_state();
asm volatile("sw_bp: brk #0");
@@ -263,6 +295,17 @@ static void guest_code(uint8_t bpn, uint8_t wpn)
: : : "x0");
GUEST_ASSERT_EQ(ss_addr[0], 0);
+ /* Linked hardware-breakpoint */
+ hw_bp_addr = 0;
+ reset_debug_state();
+ install_hw_bp_ctx(bpn, ctx_bpn, PC(hw_bp_ctx), ctx);
+ /* Set context id */
+ write_sysreg(ctx, contextidr_el1);
+ isb();
+ asm volatile("hw_bp_ctx: nop");
+ write_sysreg(0, contextidr_el1);
+ GUEST_ASSERT_EQ(hw_bp_addr, PC(hw_bp_ctx));
+
GUEST_DONE();
}
@@ -342,11 +385,12 @@ static int debug_version(uint64_t id_aa64dfr0)
return FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_DEBUGVER), id_aa64dfr0);
}
-static void test_guest_debug_exceptions(void)
+static void test_guest_debug_exceptions(uint64_t aa64dfr0)
{
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
struct ucall uc;
+ uint8_t brp_num;
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
ucall_init(vm, NULL);
@@ -365,8 +409,15 @@ 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);
+ /* Number of breakpoints */
+ brp_num = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_BRPS), aa64dfr0) + 1;
+ __TEST_REQUIRE(brp_num >= 2, "At least two breakpoints are required");
+
+ /*
+ * Run tests with breakpoint#0, watchpoint#0, and the higiest
+ * numbered (context-aware) breakpoint.
+ */
+ vcpu_args_set(vcpu, 3, 0, 0, brp_num - 1);
vcpu_run(vcpu);
switch (get_ucall(vcpu, &uc)) {
@@ -483,7 +534,7 @@ int main(int argc, char *argv[])
}
}
- test_guest_debug_exceptions();
+ test_guest_debug_exceptions(aa64dfr0);
test_single_step_from_userspace(ss_iteration);
return 0;
Currently, the debug-exceptions test doesn't have a test case for a linked breakpoint. Add a test case for the linked breakpoint to the test. The new test case uses a pair of breakpoints. One is the higiest numbered context-aware breakpoint (for Context ID match), and the other one is the breakpoint#0 (for Address Match), which is linked to the context-aware breakpoint. Signed-off-by: Reiji Watanabe <reijiw@google.com> --- .../selftests/kvm/aarch64/debug-exceptions.c | 63 +++++++++++++++++-- 1 file changed, 57 insertions(+), 6 deletions(-)