* [PATCH v5 1/2] target/arm: Provide cpu property for controling FEAT_LPA2
2022-03-04 20:02 [PATCH v5 0/2] target/arm: Enable LPA2 Richard Henderson
@ 2022-03-04 20:03 ` Richard Henderson
2022-03-04 20:03 ` [PATCH v5 2/2] hw/core: Disable LPA2 for -machine virt-6.2 Richard Henderson
1 sibling, 0 replies; 3+ messages in thread
From: Richard Henderson @ 2022-03-04 20:03 UTC (permalink / raw)
To: qemu-devel; +Cc: peter.maydell, qemu-arm
There is a Linux kernel bug present until v5.12 that prevents
booting with FEAT_LPA2 enabled. As a workaround for TCG, allow
the feature to be disabled from -cpu max.
Since this kernel bug is present in the Fedora 31 image that
we test in avocado, disable lpa2 on the command-line.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
target/arm/cpu.h | 5 ++++-
target/arm/cpu.c | 6 ++++++
target/arm/cpu64.c | 24 ++++++++++++++++++++++++
tests/avocado/boot_linux.py | 2 ++
4 files changed, 36 insertions(+), 1 deletion(-)
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 24d9fff170..4aa70ceca1 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -204,10 +204,12 @@ typedef struct {
# define ARM_MAX_VQ 16
void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp);
void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp);
+void arm_cpu_lpa2_finalize(ARMCPU *cpu, Error **errp);
#else
# define ARM_MAX_VQ 1
static inline void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) { }
static inline void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp) { }
+static inline void arm_cpu_lpa2_finalize(ARMCPU *cpu, Error **errp) { }
#endif
typedef struct ARMVectorReg {
@@ -975,10 +977,11 @@ struct ARMCPU {
/*
* Intermediate values used during property parsing.
- * Once finalized, the values should be read from ID_AA64ISAR1.
+ * Once finalized, the values should be read from ID_AA64*.
*/
bool prop_pauth;
bool prop_pauth_impdef;
+ bool prop_lpa2;
/* DCZ blocksize, in log_2(words), ie low 4 bits of DCZID_EL0 */
uint32_t dcz_blocksize;
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 7091684a16..185d4e774d 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -1392,6 +1392,12 @@ void arm_cpu_finalize_features(ARMCPU *cpu, Error **errp)
error_propagate(errp, local_err);
return;
}
+
+ arm_cpu_lpa2_finalize(cpu, &local_err);
+ if (local_err != NULL) {
+ error_propagate(errp, local_err);
+ return;
+ }
}
if (kvm_enabled()) {
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 2fdc16bf18..eb44c05822 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -688,6 +688,29 @@ void aarch64_add_pauth_properties(Object *obj)
}
}
+static Property arm_cpu_lpa2_property =
+ DEFINE_PROP_BOOL("lpa2", ARMCPU, prop_lpa2, true);
+
+void arm_cpu_lpa2_finalize(ARMCPU *cpu, Error **errp)
+{
+ uint64_t t;
+
+ /*
+ * We only install the property for tcg -cpu max; this is the
+ * only situation in which the cpu field can be true.
+ */
+ if (!cpu->prop_lpa2) {
+ return;
+ }
+
+ t = cpu->isar.id_aa64mmfr0;
+ t = FIELD_DP64(t, ID_AA64MMFR0, TGRAN16, 2); /* 16k pages w/ LPA2 */
+ t = FIELD_DP64(t, ID_AA64MMFR0, TGRAN4, 1); /* 4k pages w/ LPA2 */
+ t = FIELD_DP64(t, ID_AA64MMFR0, TGRAN16_2, 3); /* 16k stage2 w/ LPA2 */
+ t = FIELD_DP64(t, ID_AA64MMFR0, TGRAN4_2, 3); /* 4k stage2 w/ LPA2 */
+ cpu->isar.id_aa64mmfr0 = t;
+}
+
static void aarch64_host_initfn(Object *obj)
{
#if defined(CONFIG_KVM)
@@ -897,6 +920,7 @@ static void aarch64_max_initfn(Object *obj)
aarch64_add_sve_properties(obj);
object_property_add(obj, "sve-max-vq", "uint32", cpu_max_get_sve_max_vq,
cpu_max_set_sve_max_vq, NULL, NULL);
+ qdev_property_add_static(DEVICE(obj), &arm_cpu_lpa2_property);
}
static void aarch64_a64fx_initfn(Object *obj)
diff --git a/tests/avocado/boot_linux.py b/tests/avocado/boot_linux.py
index ab19146d1e..ee584d2fdf 100644
--- a/tests/avocado/boot_linux.py
+++ b/tests/avocado/boot_linux.py
@@ -79,6 +79,7 @@ def test_virt_tcg_gicv2(self):
"""
self.require_accelerator("tcg")
self.vm.add_args("-accel", "tcg")
+ self.vm.add_args("-cpu", "max,lpa2=off")
self.vm.add_args("-machine", "virt,gic-version=2")
self.add_common_args()
self.launch_and_wait(set_up_ssh_connection=False)
@@ -91,6 +92,7 @@ def test_virt_tcg_gicv3(self):
"""
self.require_accelerator("tcg")
self.vm.add_args("-accel", "tcg")
+ self.vm.add_args("-cpu", "max,lpa2=off")
self.vm.add_args("-machine", "virt,gic-version=3")
self.add_common_args()
self.launch_and_wait(set_up_ssh_connection=False)
--
2.25.1
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