On Sat, Jun 10, 2023 at 01:32:59AM -0700, Nadav Amit wrote: > > > On May 30, 2023, at 9:08 AM, Nikos Nikoleris <nikos.nikoleris@xxxxxxx> wrote: > > > > Hello, > > > > This series adds initial support for building arm64 tests as EFI > > apps and running them under QEMU. Much like x86_64, we import external > > dependencies from gnu-efi and adapt them to work with types and other > > assumptions from kvm-unit-tests. In addition, this series adds support > > for enumerating parts of the system using ACPI. > > Just an issue I encountered, which I am not sure is arm64 specific: > > All the printf’s in efi_main() are before current_thread_info() is > initialized (or even memset’d to zero, as done in setup_efi). > > But printf() calls puts() which checks if mmu_enabled(). And > mmu_enabled() uses is_user() and current_thread_info()->cpu, both > of which read uninitialized data from current_thread_info(). > > IOW: Any printf in efi_main() can cause a crash. > Nice catch, Nadav. Nikos, shouldn't we drop the memset() in setup_efi and put a zero_range call, similar to the one in arm/cstart64.S which zero's the thread-info area, in arm/efi/crt0-efi-aarch64.S? Thanks, drew
