Auger Eric [off-list ref] writes:

Hi Alex,

On 5/25/21 7:26 PM, Alex Bennée wrote:

quoted

When running the test in TCG we are basically running on bare metal so
don't rely on having a particular kernel errata applied.

You might wonder why we handle this with a totally new test name
instead of adjusting the append to take an extra parameter? Well the
run_migration shell script uses eval "$@" which unwraps the -append
leading to any second parameter being split and leaving QEMU very
confused and the test hanging. This seemed simpler than re-writing all
the test running logic in something sane ;-)

there is
lib/s390x/vm.h:bool vm_is_tcg(void)

but I don't see any particular ID we could use to differentiate both the
KVM and the TCG mode, do you?

For -cpu max we do:

        /*
         * Reset MIDR so the guest doesn't mistake our 'max' CPU type for a real
         * one and try to apply errata workarounds or use impdef features we
         * don't provide.
         * An IMPLEMENTER field of 0 means "reserved for software use";
         * ARCHITECTURE must be 0xf indicating "v7 or later, check ID registers
         * to see which features are present";
         * the VARIANT, PARTNUM and REVISION fields are all implementation
         * defined and we choose to define PARTNUM just in case guest
         * code needs to distinguish this QEMU CPU from other software
         * implementations, though this shouldn't be needed.
         */
        t = FIELD_DP64(0, MIDR_EL1, IMPLEMENTER, 0);
        t = FIELD_DP64(t, MIDR_EL1, ARCHITECTURE, 0xf);
        t = FIELD_DP64(t, MIDR_EL1, PARTNUM, 'Q');
        t = FIELD_DP64(t, MIDR_EL1, VARIANT, 0);
        t = FIELD_DP64(t, MIDR_EL1, REVISION, 0);
        cpu->midr = t;

However for the default -cpu cortex-a57 we aim to look just like the
real thing - only without any annoying micro-architecture bugs ;-)

without a more elegant solution,

I'll look into the suggestion made by Richard.

Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric

quoted

Signed-off-by: Alex Bennée <redacted>
Cc: Shashi Mallela <redacted>
---
 arm/gic.c         |  8 +++++++-
 arm/unittests.cfg | 10 +++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/arm/gic.c b/arm/gic.c
index bef061a..0fce2a4 100644
--- a/arm/gic.c
+++ b/arm/gic.c

@@ -36,6 +36,7 @@ static struct gic *gic;
 static int acked[NR_CPUS], spurious[NR_CPUS];
 static int irq_sender[NR_CPUS], irq_number[NR_CPUS];
 static cpumask_t ready;
+static bool under_tcg;
 
 static void nr_cpu_check(int nr)
 {

@@ -834,7 +835,7 @@ static void test_migrate_unmapped_collection(void)
 		goto do_migrate;
 	}
 
-	if (!errata(ERRATA_UNMAPPED_COLLECTIONS)) {
+	if (!errata(ERRATA_UNMAPPED_COLLECTIONS) && !under_tcg) {
 		report_skip("Skipping test, as this test hangs without the fix. "
 			    "Set %s=y to enable.", ERRATA_UNMAPPED_COLLECTIONS);
 		test_skipped = true;

@@ -1005,6 +1006,11 @@ int main(int argc, char **argv)
 		report_prefix_push(argv[1]);
 		test_migrate_unmapped_collection();
 		report_prefix_pop();
+	} else if (!strcmp(argv[1], "its-migrate-unmapped-collection-tcg")) {
+		under_tcg = true;
+		report_prefix_push(argv[1]);
+		test_migrate_unmapped_collection();
+		report_prefix_pop();
 	} else if (strcmp(argv[1], "its-introspection") == 0) {
 		report_prefix_push(argv[1]);
 		test_its_introspection();

diff --git a/arm/unittests.cfg b/arm/unittests.cfg
index 1a39428..adc1bbf 100644
--- a/arm/unittests.cfg
+++ b/arm/unittests.cfg

@@ -205,7 +205,7 @@ extra_params = -machine gic-version=3 -append 'its-pending-migration'
 groups = its migration
 arch = arm64
 
-[its-migrate-unmapped-collection]
+[its-migrate-unmapped-collection-kvm]
 file = gic.flat
 smp = $MAX_SMP
 accel = kvm

@@ -213,6 +213,14 @@ extra_params = -machine gic-version=3 -append 'its-migrate-unmapped-collection'
 groups = its migration
 arch = arm64
 
+[its-migrate-unmapped-collection-tcg]
+file = gic.flat
+smp = $MAX_SMP
+accel = tcg
+extra_params = -machine gic-version=3 -append 'its-migrate-unmapped-collection-tcg'
+groups = its migration
+arch = arm64
+
 # Test PSCI emulation
 [psci]
 file = psci.flat

-- 
Alex Bennée

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