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| author | Christian Krinitsin <mail@krinitsin.com> | 2025-05-21 21:21:26 +0200 |
|---|---|---|
| committer | Christian Krinitsin <mail@krinitsin.com> | 2025-05-21 21:21:26 +0200 |
| commit | 4b927bc37359dec23f67d3427fc982945f24f404 (patch) | |
| tree | 245449ef9146942dc7fffd0235b48b7e70a00bf2 /gitlab/issues/target_arm/host_missing/accel_missing/1899.toml | |
| parent | aa8bd79cec7bf6790ddb01d156c2ef2201abbaab (diff) | |
| download | qemu-analysis-4b927bc37359dec23f67d3427fc982945f24f404.tar.gz qemu-analysis-4b927bc37359dec23f67d3427fc982945f24f404.zip | |
add gitlab issues in toml format
Diffstat (limited to 'gitlab/issues/target_arm/host_missing/accel_missing/1899.toml')
| -rw-r--r-- | gitlab/issues/target_arm/host_missing/accel_missing/1899.toml | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/gitlab/issues/target_arm/host_missing/accel_missing/1899.toml b/gitlab/issues/target_arm/host_missing/accel_missing/1899.toml new file mode 100644 index 000000000..9501e522d --- /dev/null +++ b/gitlab/issues/target_arm/host_missing/accel_missing/1899.toml @@ -0,0 +1,49 @@ +id = 1899 +title = "AArch64: Wrong SCR_EL3 after turning on secondary cores via PSCI" +state = "closed" +created_at = "2023-09-21T13:00:42.972Z" +closed_at = "2023-10-21T07:31:16.981Z" +labels = ["kind::Bug", "target: arm", "workflow::Patch available"] +url = "https://gitlab.com/qemu-project/qemu/-/issues/1899" +host-os = "openSUSE Tumbleweed" +host-arch = "x86_64" +qemu-version = "current master ( 55394dcbec) + https://lore.kernel.org/qemu-devel/4831384.GXAFRqVoOG@linux-e202.suse.de/" +guest-os = "Linux / Windows 11" +guest-arch = "aarch64" +description = """The system fails to boot when using "direct kernel boot" with EL3 enabled. After the guest OS enables secondary cores via PSCI, those have an incorrectly set up `SCR_EL3`. When the OS then executes an intruction which traps into (QEMU provided fake) EL3, the core ends up in an endless loop of "Undefined Instruction" exceptions. + +This is nicely visible with `-serial stdio -append "earlycon=pl011,0x9000000 console=/dev/ttyAMA0" -d int`: + +```plaintext +[ 0.173173][ T1] smp: Bringing up secondary CPUs ... +(...) +Taking exception 11 [Hypervisor Call] on CPU 0 +...from EL1 to EL2 +...with ESR 0x16/0x5a000000 +...handled as PSCI call +Taking exception 5 [IRQ] on CPU 0 +...from EL1 to EL1 +...with ESR 0x16/0x5a000000 +...with ELR 0xffffa9ff8b593438 +...to EL1 PC 0xffffa9ff8aa11280 PSTATE 0x3c5 +Exception return from AArch64 EL1 to AArch64 EL1 PC 0xffffa9ff8b593438 +Exception return from AArch64 EL1 to AArch64 EL1 PC 0x41f7832c +Taking exception 1 [Undefined Instruction] on CPU 1 +...from EL1 to EL3 +...with ESR 0x18/0x62300882 +...with ELR 0xffffa9ff8aa3d0d8 +...to EL3 PC 0x400 PSTATE 0x3cd +Taking exception 1 [Undefined Instruction] on CPU 1 +...from EL3 to EL3 +...with ESR 0x0/0x2000000 +...with ELR 0x400 +...to EL3 PC 0x200 PSTATE 0x3cd +(repeats forever, CPU 1 is stuck) +```""" +reproduce = """1. `qemu-system-aarch64 -M virt,secure=on -cpu max -smp 1 -kernel linux` works +2. `qemu-system-aarch64 -M virt,secure=on -cpu max -smp 2 -kernel linux` does not""" +additional = """The setup for `SCR_EL3` is done by `do_cpu_reset` in hw/arm/boot.c, but this is only called on full system reset. The PSCI call ends up in `arm_set_cpu_on_async_work` (target/arm/arm-powerctl.c) which calls `cpu_reset`. This clears `SCR_EL3` to the architectural reset value, not the one needed for direct kernel boot. + +`arm_set_cpu_on_async_work` has code for `SCR_HCE`, but none of the other flags handled by `do_cpu_reset`. It would probably work after copying all of `do_cpu_reset` into `arm_set_cpu_on_async_work`, but that seems wrong. I prepared a patch which makes `do_cpu_reset` public such that `arm_set_cpu_on_async_work` can call it (works here), but I'm not sure whether that's the right way. + +CC @pm215""" |