AArch64: don't expose FDT to kernel

There is a check that if FDT is stub when ACPI table initialized in linux kernel [1]. So, if full FDT is given, FDT will be used instead of ACPI. It is aginst our primary goal to use UEFI. So, full FDT can't be given here. For simplicity, just neglict it here. Remember that this is just a workaround as we are required to pass a FDT to kernel/grub to meet Arm Base Boot Requirement 7.4.3 [2]. It can be improved by making a stub FDT and pass it through configuration table. Maybe later. Fixes: cloud-hypervisor#261 Signed-off-by: Jianyong Wu <[email protected]> [1] https://github.com/torvalds/linux/blob/d528014517f2b0531862c02865b9d4c908019dc4/arch/arm64/kernel/acpi.c#L203 [2] https://developer.arm.com/documentation/den0044/latest
jongwu · Jul 20, 2023 · 3e5cf85 · 3e5cf85
1 parent d551946
commit 3e5cf85
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/src/efi/mod.rs b/src/efi/mod.rs
@@ -1115,6 +1115,10 @@ pub fn efi_exec(
     let mut ct_index = 0;
 
     // Populate with FDT table if present
+    // To boot linux kernel with ACPI, we can't offer full fdt. Simply, neglect
+    // it. See
+    // https://github.com/torvalds/linux/blob/d528014517f2b0531862c02865b9d4c908019dc4/arch/arm64/kernel/acpi.c#L203
+    #[cfg(not(target_arch = "aarch64"))]
     if let Some(fdt_entry) = info.fdt_reservation() {
         ct[ct_index] = efi::ConfigurationTable {
             vendor_guid: Guid::from_fields(