arch_timer_edge_cases currently fails on ampere-one machines with the following assertion failure:
==== Test Assertion Failure ==== arm64/arch_timer_edge_cases.c:169: timer_condition == istatus pid=11236 tid=11236 errno=4 - Interrupted system call 1 0x0000000000404ce7: test_run at arch_timer_edge_cases.c:938 2 0x0000000000401ebb: main at arch_timer_edge_cases.c:1053 3 0x0000ffff9fa8625b: ?? ??:0 4 0x0000ffff9fa8633b: ?? ??:0 5 0x0000000000401fef: _start at ??:? 0x1 != 0x0 (timer_condition != istatus)
Meaning that the timer condition was met and an interrupt was presented but the timer status bit in the control register was not set.
This happens due to AC03_CPU_14 "Timer CVAL programming of a delta greater than 2^63 will result in incorrect behavior."
Work around this issue by reducing the value that is used to reset the counter and thus reduce the delta.
Link: https://lore.kernel.org/kvmarm/ac1de1d2-ef2b-d439-dc48-8615e121b07b@redhat.c... Link: https://amperecomputing.com/assets/AmpereOne_Developer_ER_v0_80_20240823_289... Signed-off-by: Sebastian Ott sebott@redhat.com --- tools/testing/selftests/kvm/arm64/arch_timer_edge_cases.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/arm64/arch_timer_edge_cases.c b/tools/testing/selftests/kvm/arm64/arch_timer_edge_cases.c index a813b4c6c817..2f0397df0aa6 100644 --- a/tools/testing/selftests/kvm/arm64/arch_timer_edge_cases.c +++ b/tools/testing/selftests/kvm/arm64/arch_timer_edge_cases.c @@ -31,7 +31,7 @@ static const int32_t TVAL_MIN = INT32_MIN; static const uint32_t TIMEOUT_NO_IRQ_US = 50000;
/* A nice counter value to use as the starting one for most tests. */ -static const uint64_t DEF_CNT = (CVAL_MAX / 2); +static const uint64_t DEF_CNT = (CVAL_MAX / 4);
/* Number of runs. */ static const uint32_t NR_TEST_ITERS_DEF = 5;