From a8a788d6b79c7231dc20e869684491dca0333e41 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?= <mkroening@posteo.net>
Date: Wed, 1 Dec 2021 22:42:53 +0100
Subject: [PATCH 1/4] Upgrade toolchain channel to nightly-2021-10-20

CI: Explicitly set build-std without std
Else, cargo unifies with rusty-hermit's outer .cargo/config.toml and
tries to build std for the kernel, which fails with:

error[E0432]: unresolved import `crate::sys::hermit::thread_local_dtor`
 --> /home/mkroening/.rustup/toolchains/nightly-2021-10-20-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sys/hermit/thread.rs:9:25
  |
9 | use crate::sys::hermit::thread_local_dtor::run_dtors;
  |                         ^^^^^^^^^^^^^^^^^ could not find `thread_local_dtor` in `hermit`

error[E0432]: unresolved import `crate::sys::hermit::thread_local_dtor`
   --> /home/mkroening/.rustup/toolchains/nightly-2021-10-20-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sys/hermit/mod.rs:122:29
    |
122 |     use crate::sys::hermit::thread_local_dtor::run_dtors;
    |                             ^^^^^^^^^^^^^^^^^ could not find `thread_local_dtor` in `hermit`
---
 .cargo/config.toml        | 1 +
 .github/workflows/x86.yml | 2 +-
 rust-toolchain.toml       | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/.cargo/config.toml b/.cargo/config.toml
index 334b3e8f5b..4b1b35d413 100644
--- a/.cargo/config.toml
+++ b/.cargo/config.toml
@@ -1,4 +1,5 @@
 [unstable]
+# Keep in sync with CI!
 build-std = ["core", "alloc"]
 build-std-features = ["compiler-builtins-mem"]
 
diff --git a/.github/workflows/x86.yml b/.github/workflows/x86.yml
index 554fd66f67..04b3a29cca 100644
--- a/.github/workflows/x86.yml
+++ b/.github/workflows/x86.yml
@@ -39,7 +39,7 @@ jobs:
         run: rustup show
       - name: Build minimal kernel
         working-directory: libhermit-rs
-        run: cargo build --no-default-features
+        run: cargo build --no-default-features -Z build-std=core,alloc
       - name: Build dev profile
         run: cargo build
       - name: Unittests on host (ubuntu)
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index fe707619c2..37093c294d 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,5 +1,5 @@
 [toolchain]
-channel = "nightly-2021-09-29"
+channel = "nightly-2021-10-20"
 components = [
     "rust-src",
     "llvm-tools-preview",

From c8eb43a48ebbf42a3e7fa4762532b0b4a8d231fd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?= <mkroening@posteo.net>
Date: Wed, 1 Dec 2021 23:09:43 +0100
Subject: [PATCH 2/4] Upgrade toolchain channel to nightly-2021-11-01

The kernel's target os was removed in https://github.com/rust-lang/rust/pull/90404.
It is only used for x86_64 and not for aarch64.
Adjust filter on __rg_oom since the filter for `target_os = "hermit"` does not
work anymore for the kernel target: https://github.com/rust-lang/rust/commit/bc6b2ac449a0f6d9a8bd87788a0eae9516cb58ce
---
 rust-toolchain.toml                 |  2 +-
 src/arch/mod.rs                     |  8 ++++--
 src/arch/x86_64/kernel/apic.rs      |  4 +--
 src/arch/x86_64/kernel/irq.rs       |  2 +-
 src/arch/x86_64/kernel/mod.rs       | 25 ++++++++++---------
 src/arch/x86_64/kernel/percore.rs   |  4 +--
 src/arch/x86_64/kernel/processor.rs |  6 ++---
 src/arch/x86_64/kernel/scheduler.rs |  4 +--
 src/console.rs                      |  2 +-
 src/lib.rs                          | 38 +++++++++++++++++------------
 src/mm/allocator.rs                 |  4 +--
 src/mm/freelist.rs                  |  6 ++---
 src/mm/hole.rs                      |  6 ++---
 src/mm/mod.rs                       |  2 +-
 src/mm/test.rs                      | 30 +++++++++++------------
 src/runtime_glue.rs                 |  3 ++-
 src/syscalls/interfaces/uhyve.rs    |  2 +-
 src/syscalls/mod.rs                 |  8 +++---
 18 files changed, 85 insertions(+), 71 deletions(-)

diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index 37093c294d..bb73df0cf8 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,5 +1,5 @@
 [toolchain]
-channel = "nightly-2021-10-20"
+channel = "nightly-2021-11-01"
 components = [
     "rust-src",
     "llvm-tools-preview",
diff --git a/src/arch/mod.rs b/src/arch/mod.rs
index d9c5496b98..8d6d741739 100644
--- a/src/arch/mod.rs
+++ b/src/arch/mod.rs
@@ -44,7 +44,11 @@ pub use crate::arch::x86_64::*;
 
 #[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::kernel::apic::{set_oneshot_timer, wakeup_core};
-#[cfg(all(target_arch = "x86_64", target_os = "hermit", feature = "smp"))]
+#[cfg(all(
+	target_arch = "x86_64",
+	any(target_os = "none", target_os = "hermit"),
+	feature = "smp"
+))]
 pub use crate::arch::x86_64::kernel::application_processor_init;
 #[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::kernel::gdt::set_current_kernel_stack;
@@ -60,7 +64,7 @@ pub use crate::arch::x86_64::kernel::scheduler;
 pub use crate::arch::x86_64::kernel::switch;
 #[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::kernel::systemtime::get_boot_time;
-#[cfg(all(target_arch = "x86_64", target_os = "hermit"))]
+#[cfg(all(target_arch = "x86_64", any(target_os = "none", target_os = "hermit")))]
 pub use crate::arch::x86_64::kernel::{boot_application_processors, boot_processor_init};
 #[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::kernel::{
diff --git a/src/arch/x86_64/kernel/apic.rs b/src/arch/x86_64/kernel/apic.rs
index 688e87ad50..8b222ecec6 100644
--- a/src/arch/x86_64/kernel/apic.rs
+++ b/src/arch/x86_64/kernel/apic.rs
@@ -2,7 +2,7 @@ use crate::arch;
 #[cfg(feature = "acpi")]
 use crate::arch::x86_64::kernel::acpi;
 use crate::arch::x86_64::kernel::irq::IrqStatistics;
-#[cfg(all(target_os = "hermit", feature = "smp"))]
+#[cfg(all(any(target_os = "none", target_os = "hermit"), feature = "smp"))]
 use crate::arch::x86_64::kernel::smp_boot_code::SMP_BOOT_CODE;
 use crate::arch::x86_64::kernel::IRQ_COUNTERS;
 use crate::arch::x86_64::mm::paging::{BasePageSize, PageSize, PageTableEntryFlags};
@@ -568,7 +568,7 @@ extern "C" {
 /// This algorithm is derived from Intel MultiProcessor Specification 1.4, B.4, but testing has shown
 /// that a second STARTUP IPI and setting the BIOS Reset Vector are no longer necessary.
 /// This is partly confirmed by https://wiki.osdev.org/Symmetric_Multiprocessing
-#[cfg(all(target_os = "hermit", feature = "smp"))]
+#[cfg(all(any(target_os = "none", target_os = "hermit"), feature = "smp"))]
 pub fn boot_application_processors() {
 	// We shouldn't have any problems fitting the boot code into a single page, but let's better be sure.
 	assert!(
diff --git a/src/arch/x86_64/kernel/irq.rs b/src/arch/x86_64/kernel/irq.rs
index 6d9e0ec3ac..b8e96d03bc 100644
--- a/src/arch/x86_64/kernel/irq.rs
+++ b/src/arch/x86_64/kernel/irq.rs
@@ -90,7 +90,7 @@ pub fn disable() {
 /// were not activated before calling this function.
 #[inline]
 pub fn nested_disable() -> bool {
-	cfg!(target_os = "hermit") && {
+	cfg!(any(target_os = "none", target_os = "hermit")) && {
 		let ret = rflags::read().contains(RFlags::FLAGS_IF);
 		disable();
 		ret
diff --git a/src/arch/x86_64/kernel/mod.rs b/src/arch/x86_64/kernel/mod.rs
index cc57b123b6..7f95415aa0 100644
--- a/src/arch/x86_64/kernel/mod.rs
+++ b/src/arch/x86_64/kernel/mod.rs
@@ -119,14 +119,14 @@ impl BootInfo {
 }
 
 /// Kernel header to announce machine features
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 static mut BOOT_INFO: *mut BootInfo = ptr::null_mut();
 
-#[cfg(all(target_os = "hermit", not(feature = "newlib")))]
+#[cfg(all(any(target_os = "none", target_os = "hermit"), not(feature = "newlib")))]
 #[link_section = ".data"]
 static mut BOOT_INFO: *mut BootInfo = ptr::null_mut();
 
-#[cfg(all(target_os = "hermit", feature = "newlib"))]
+#[cfg(all(any(target_os = "none", target_os = "hermit"), feature = "newlib"))]
 #[link_section = ".mboot"]
 static mut BOOT_INFO: *mut BootInfo = ptr::null_mut();
 
@@ -298,7 +298,10 @@ pub fn message_output_init() {
 	}
 }
 
-#[cfg(all(not(target_os = "hermit"), not(target_os = "windows")))]
+#[cfg(all(
+	not(any(target_os = "none", target_os = "hermit")),
+	not(target_os = "windows")
+))]
 pub fn output_message_byte(byte: u8) {
 	extern "C" {
 		fn write(fd: i32, buf: *const u8, count: usize) -> isize;
@@ -320,7 +323,7 @@ pub fn output_message_byte(byte: u8) {
 	}
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[test]
 fn test_output() {
 	output_message_byte('t' as u8);
@@ -330,7 +333,7 @@ fn test_output() {
 	output_message_byte('\n' as u8);
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub fn output_message_byte(byte: u8) {
 	if environment::is_single_kernel() {
 		// Output messages to the serial port and VGA screen in unikernel mode.
@@ -348,7 +351,7 @@ pub fn output_message_byte(byte: u8) {
 	}
 }
 
-//#[cfg(target_os = "hermit")]
+//#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub fn output_message_buf(buf: &[u8]) {
 	for byte in buf {
 		output_message_byte(*byte);
@@ -356,7 +359,7 @@ pub fn output_message_buf(buf: &[u8]) {
 }
 
 /// Real Boot Processor initialization as soon as we have put the first Welcome message on the screen.
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub fn boot_processor_init() {
 	processor::detect_features();
 	processor::configure();
@@ -403,7 +406,7 @@ pub fn boot_processor_init() {
 
 /// Boots all available Application Processors on bare-metal or QEMU.
 /// Called after the Boot Processor has been fully initialized along with its scheduler.
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub fn boot_application_processors() {
 	#[cfg(feature = "smp")]
 	apic::boot_application_processors();
@@ -411,7 +414,7 @@ pub fn boot_application_processors() {
 }
 
 /// Application Processor initialization
-#[cfg(all(target_os = "hermit", feature = "smp"))]
+#[cfg(all(any(target_os = "none", target_os = "hermit"), feature = "smp"))]
 pub fn application_processor_init() {
 	percore::init();
 	processor::configure();
@@ -466,7 +469,7 @@ pub fn print_statistics() {
 	}
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[inline(never)]
 #[no_mangle]
 unsafe fn pre_init(boot_info: &'static mut BootInfo) -> ! {
diff --git a/src/arch/x86_64/kernel/percore.rs b/src/arch/x86_64/kernel/percore.rs
index aa3324faad..7bee11e01e 100644
--- a/src/arch/x86_64/kernel/percore.rs
+++ b/src/arch/x86_64/kernel/percore.rs
@@ -137,13 +137,13 @@ impl<T: Is32BitVariable> PerCoreVariableMethods<T> for PerCoreVariable<T> {
 	}
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[inline]
 pub fn core_id() -> CoreId {
 	unsafe { PERCORE.core_id.get() }
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 pub fn core_id() -> CoreId {
 	0
 }
diff --git a/src/arch/x86_64/kernel/processor.rs b/src/arch/x86_64/kernel/processor.rs
index 13bc22e4bd..936d0d4a07 100644
--- a/src/arch/x86_64/kernel/processor.rs
+++ b/src/arch/x86_64/kernel/processor.rs
@@ -337,14 +337,14 @@ impl CpuFrequency {
 		pic::eoi(pit::PIT_INTERRUPT_NUMBER);
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	fn measure_frequency(&mut self) -> Result<(), ()> {
 		// return just Ok because the real implementation must run in ring 0
 		self.source = CpuFrequencySources::Measurement;
 		Ok(())
 	}
 
-	#[cfg(target_os = "hermit")]
+	#[cfg(any(target_os = "none", target_os = "hermit"))]
 	fn measure_frequency(&mut self) -> Result<(), ()> {
 		// The PIC is not initialized for uhyve, so we cannot measure anything.
 		if environment::is_uhyve() {
@@ -865,7 +865,7 @@ pub fn print_information() {
 	infofooter!();
 }
 
-/*#[cfg(not(target_os = "hermit"))]
+/*#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[test]
 fn print_cpu_information() {
 	::logging::init();
diff --git a/src/arch/x86_64/kernel/scheduler.rs b/src/arch/x86_64/kernel/scheduler.rs
index 2aabfe14d8..bfcfa8bda4 100644
--- a/src/arch/x86_64/kernel/scheduler.rs
+++ b/src/arch/x86_64/kernel/scheduler.rs
@@ -305,12 +305,12 @@ impl Clone for TaskTLS {
 	}
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 extern "C" fn task_start(_f: extern "C" fn(usize), _arg: usize, _user_stack: u64) -> ! {
 	unimplemented!()
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[naked]
 extern "C" fn task_start(_f: extern "C" fn(usize), _arg: usize, _user_stack: u64) -> ! {
 	// `f` is in the `rdi` register
diff --git a/src/console.rs b/src/console.rs
index 0682612aa4..d9155c703c 100644
--- a/src/console.rs
+++ b/src/console.rs
@@ -31,7 +31,7 @@ impl Console {
 
 pub static CONSOLE: SpinlockIrqSave<Console> = SpinlockIrqSave::new(Console(()));
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[test]
 fn test_console() {
 	println!("HelloWorld");
diff --git a/src/lib.rs b/src/lib.rs
index 897f28dc48..ae5f6d6e6f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -30,13 +30,19 @@
 #![feature(llvm_asm)]
 #![feature(global_asm)]
 #![no_std]
-#![cfg_attr(target_os = "hermit", feature(custom_test_frameworks))]
-#![cfg_attr(target_os = "hermit", cfg_attr(test, test_runner(crate::test_runner)))]
 #![cfg_attr(
-	target_os = "hermit",
+	any(target_os = "none", target_os = "hermit"),
+	feature(custom_test_frameworks)
+)]
+#![cfg_attr(
+	any(target_os = "none", target_os = "hermit"),
+	cfg_attr(test, test_runner(crate::test_runner))
+)]
+#![cfg_attr(
+	any(target_os = "none", target_os = "hermit"),
 	cfg_attr(test, reexport_test_harness_main = "test_main")
 )]
-#![cfg_attr(target_os = "hermit", cfg_attr(test, no_main))]
+#![cfg_attr(any(target_os = "none", target_os = "hermit"), cfg_attr(test, no_main))]
 
 // EXTERNAL CRATES
 #[macro_use]
@@ -47,7 +53,7 @@ extern crate bitflags;
 extern crate log;
 #[macro_use]
 extern crate num_derive;
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[macro_use]
 extern crate std;
 #[cfg(target_arch = "aarch64")]
@@ -88,7 +94,7 @@ mod errno;
 mod ffi;
 mod kernel_message_buffer;
 mod mm;
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 mod runtime_glue;
 mod scheduler;
 mod synch;
@@ -102,7 +108,7 @@ pub fn _print(args: ::core::fmt::Arguments<'_>) {
 }
 
 #[cfg(test)]
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[no_mangle]
 extern "C" fn runtime_entry(_argc: i32, _argv: *const *const u8, _env: *const *const u8) -> ! {
 	println!("Executing hermit unittests. Any arguments are dropped");
@@ -120,14 +126,14 @@ pub fn test_runner(tests: &[&dyn Fn()]) {
 	sys_exit(0);
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[test_case]
 fn trivial_test() {
 	println!("Test test test");
 	panic!("Test called");
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[global_allocator]
 static ALLOCATOR: LockedHeap = LockedHeap::empty();
 
@@ -137,7 +143,7 @@ static ALLOCATOR: LockedHeap = LockedHeap::empty();
 /// Returning a null pointer indicates that either memory is exhausted or
 /// `size` and `align` do not meet this allocator's size or alignment constraints.
 ///
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub extern "C" fn __sys_malloc(size: usize, align: usize) -> *mut u8 {
 	let layout_res = Layout::from_size_align(size, align);
 	if layout_res.is_err() || size == 0 {
@@ -179,7 +185,7 @@ pub extern "C" fn __sys_malloc(size: usize, align: usize) -> *mut u8 {
 /// # Errors
 /// Returns null if the new layout does not meet the size and alignment constraints of the
 /// allocator, or if reallocation otherwise fails.
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub extern "C" fn __sys_realloc(
 	ptr: *mut u8,
 	size: usize,
@@ -224,7 +230,7 @@ pub extern "C" fn __sys_realloc(
 ///
 /// # Errors
 /// May panic if debug assertions are enabled and invalid parameters `size` or `align` where passed.
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub extern "C" fn __sys_free(ptr: *mut u8, size: usize, align: usize) {
 	unsafe {
 		let layout_res = Layout::from_size_align(size, align);
@@ -247,7 +253,7 @@ pub extern "C" fn __sys_free(ptr: *mut u8, size: usize, align: usize) {
 	}
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 extern "C" {
 	static mut __bss_start: usize;
 }
@@ -259,7 +265,7 @@ fn has_ipdevice() -> bool {
 }
 
 /// Entry point of a kernel thread, which initialize the libos
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 extern "C" fn initd(_arg: usize) {
 	extern "C" {
 		#[cfg(not(test))]
@@ -319,7 +325,7 @@ fn synch_all_cores() {
 }
 
 /// Entry Point of HermitCore for the Boot Processor
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 fn boot_processor_main() -> ! {
 	// Initialize the kernel and hardware.
 	arch::message_output_init();
@@ -372,7 +378,7 @@ fn boot_processor_main() -> ! {
 }
 
 /// Entry Point of HermitCore for an Application Processor
-#[cfg(all(target_os = "hermit", feature = "smp"))]
+#[cfg(all(any(target_os = "none", target_os = "hermit"), feature = "smp"))]
 fn application_processor_main() -> ! {
 	arch::application_processor_init();
 	scheduler::add_current_core();
diff --git a/src/mm/allocator.rs b/src/mm/allocator.rs
index 6a31d99e27..ce2c14e2a7 100644
--- a/src/mm/allocator.rs
+++ b/src/mm/allocator.rs
@@ -31,9 +31,9 @@ pub struct Heap {
 	index: usize,
 	bottom: usize,
 	size: usize,
-	#[cfg(target_os = "hermit")]
+	#[cfg(any(target_os = "none", target_os = "hermit"))]
 	holes: HoleList,
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	pub holes: HoleList,
 }
 
diff --git a/src/mm/freelist.rs b/src/mm/freelist.rs
index 5dd5b2576e..7db3bd02fc 100644
--- a/src/mm/freelist.rs
+++ b/src/mm/freelist.rs
@@ -190,7 +190,7 @@ impl FreeList {
 	}
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[test]
 fn add_element() {
 	let mut freelist = FreeList::new();
@@ -208,7 +208,7 @@ fn add_element() {
 	}
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[test]
 fn allocate() {
 	let mut freelist = FreeList::new();
@@ -241,7 +241,7 @@ fn allocate() {
 	}
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[test]
 fn deallocate() {
 	let mut freelist = FreeList::new();
diff --git a/src/mm/hole.rs b/src/mm/hole.rs
index 86a9337221..c1fa95c422 100644
--- a/src/mm/hole.rs
+++ b/src/mm/hole.rs
@@ -80,7 +80,7 @@ impl HoleList {
 	}
 
 	/// Returns information about the first hole for test purposes.
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[cfg(test)]
 	pub fn first_hole(&self) -> Option<(usize, usize)> {
 		self.first
@@ -91,13 +91,13 @@ impl HoleList {
 }
 
 /// A block containing free memory. It points to the next hole and thus forms a linked list.
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub struct Hole {
 	size: usize,
 	next: Option<&'static mut Hole>,
 }
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 pub struct Hole {
 	pub size: usize,
 	pub next: Option<&'static mut Hole>,
diff --git a/src/mm/mod.rs b/src/mm/mod.rs
index 97a04f9627..4299bec47e 100644
--- a/src/mm/mod.rs
+++ b/src/mm/mod.rs
@@ -71,7 +71,7 @@ fn map_heap<S: PageSize>(virt_addr: VirtAddr, size: usize) -> usize {
 	i
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 pub fn init() {
 	// Calculate the start and end addresses of the 2 MiB page(s) that map the kernel.
 	unsafe {
diff --git a/src/mm/test.rs b/src/mm/test.rs
index a17d6ab2fb..dda0e90562 100644
--- a/src/mm/test.rs
+++ b/src/mm/test.rs
@@ -5,7 +5,7 @@
 // To avoid false sharing, our version allocate as smallest block 64 byte (= cache line).
 // In addition, for pre
 
-#[cfg(not(target_os = "hermit"))]
+#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 #[cfg(test)]
 mod tests {
 	use super::*;
@@ -42,7 +42,7 @@ mod tests {
 		heap
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn empty() {
 		let mut heap = Heap::empty();
@@ -55,7 +55,7 @@ mod tests {
 		assert!(addr.is_err());
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn oom() {
 		let mut heap = new_heap();
@@ -64,7 +64,7 @@ mod tests {
 		assert!(addr.is_err());
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn allocate_double_usize() {
 		let mut heap = new_heap();
@@ -86,7 +86,7 @@ mod tests {
 		}
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn allocate_and_free_double_usize() {
 		let mut heap = new_heap();
@@ -102,7 +102,7 @@ mod tests {
 		}
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn deallocate_right_before() {
 		let mut heap = new_heap();
@@ -129,7 +129,7 @@ mod tests {
 		}
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn deallocate_right_behind() {
 		let mut heap = new_heap();
@@ -151,7 +151,7 @@ mod tests {
 		}
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn deallocate_middle() {
 		let mut heap = new_heap();
@@ -178,7 +178,7 @@ mod tests {
 		}
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn reallocate_double_usize() {
 		let mut heap = new_heap();
@@ -198,7 +198,7 @@ mod tests {
 		assert_eq!(x, y);
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn allocate_usize() {
 		let mut heap = new_heap();
@@ -208,7 +208,7 @@ mod tests {
 		assert!(heap.allocate_first_fit(layout.clone()).is_ok());
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn allocate_usize_in_bigger_block() {
 		let mut heap = new_heap();
@@ -233,7 +233,7 @@ mod tests {
 		}
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	// see https://github.com/phil-opp/blog_os/issues/160
 	fn align_from_small_to_big() {
@@ -248,7 +248,7 @@ mod tests {
 		assert!(heap.allocate_first_fit(layout_2.clone()).is_ok());
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn extend_empty_heap() {
 		let mut heap = new_max_heap();
@@ -262,7 +262,7 @@ mod tests {
 		assert!(heap.allocate_first_fit(layout.clone()).is_ok());
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn extend_full_heap() {
 		let mut heap = new_max_heap();
@@ -277,7 +277,7 @@ mod tests {
 		assert!(heap.allocate_first_fit(layout.clone()).is_ok());
 	}
 
-	#[cfg(not(target_os = "hermit"))]
+	#[cfg(not(any(target_os = "none", target_os = "hermit")))]
 	#[test]
 	fn extend_fragmented_heap() {
 		let mut heap = new_max_heap();
diff --git a/src/runtime_glue.rs b/src/runtime_glue.rs
index 8a9e65271d..c81cbcd2f3 100644
--- a/src/runtime_glue.rs
+++ b/src/runtime_glue.rs
@@ -7,7 +7,7 @@ use alloc::alloc::Layout;
 use core::panic::PanicInfo;
 
 // see https://users.rust-lang.org/t/psa-breaking-change-panic-fmt-language-item-removed-in-favor-of-panic-implementation/17875
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[panic_handler]
 fn panic(info: &PanicInfo<'_>) -> ! {
 	print!("[{}][!!!PANIC!!!] ", arch::percore::core_id());
@@ -44,6 +44,7 @@ fn rust_oom(layout: Layout) -> ! {
 	}
 }
 
+#[cfg(target_os = "hermit")]
 #[no_mangle]
 pub unsafe extern "C" fn __rg_oom(size: usize, align: usize) -> ! {
 	let layout = Layout::from_size_align_unchecked(size, align);
diff --git a/src/syscalls/interfaces/uhyve.rs b/src/syscalls/interfaces/uhyve.rs
index a13bcc74d9..bad7c4df05 100644
--- a/src/syscalls/interfaces/uhyve.rs
+++ b/src/syscalls/interfaces/uhyve.rs
@@ -207,7 +207,7 @@ impl SyscallInterface for Uhyve {
 	///
 	/// ToDo: Add Safety section under which circumctances this is safe/unsafe to use
 	/// ToDo: Add an Errors section - What happens when e.g. malloc fails, how is that handled (currently it isn't)
-	#[cfg(target_os = "hermit")]
+	#[cfg(any(target_os = "none", target_os = "hermit"))]
 	fn get_application_parameters(&self) -> (i32, *const *const u8, *const *const u8) {
 		// determine the number of arguments and environment variables
 		let mut syscmdsize = SysCmdsize::new();
diff --git a/src/syscalls/mod.rs b/src/syscalls/mod.rs
index 2ba403ce44..b61ee7f251 100644
--- a/src/syscalls/mod.rs
+++ b/src/syscalls/mod.rs
@@ -6,7 +6,7 @@ use crate::environment;
 #[cfg(feature = "newlib")]
 use crate::synch::spinlock::SpinlockIrqSave;
 use crate::syscalls::interfaces::SyscallInterface;
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 use crate::{__sys_free, __sys_malloc, __sys_realloc};
 
 pub use self::condvar::*;
@@ -60,19 +60,19 @@ pub fn init() {
 	sbrk_init();
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[no_mangle]
 pub extern "C" fn sys_malloc(size: usize, align: usize) -> *mut u8 {
 	__sys_malloc(size, align)
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[no_mangle]
 pub extern "C" fn sys_realloc(ptr: *mut u8, size: usize, align: usize, new_size: usize) -> *mut u8 {
 	__sys_realloc(ptr, size, align, new_size)
 }
 
-#[cfg(target_os = "hermit")]
+#[cfg(any(target_os = "none", target_os = "hermit"))]
 #[no_mangle]
 pub extern "C" fn sys_free(ptr: *mut u8, size: usize, align: usize) {
 	__sys_free(ptr, size, align)

From e5cceb583cb2b6560f6800efe91ab407ca290e4a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?= <mkroening@posteo.net>
Date: Wed, 1 Dec 2021 23:26:24 +0100
Subject: [PATCH 3/4] Upgrade toolchain channel to nightly-2021-11-08

Experimental features have been split off of the `asm` feature gate.
---
 rust-toolchain.toml | 2 +-
 src/lib.rs          | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index bb73df0cf8..cf9f83138f 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,5 +1,5 @@
 [toolchain]
-channel = "nightly-2021-11-01"
+channel = "nightly-2021-11-08"
 components = [
     "rust-src",
     "llvm-tools-preview",
diff --git a/src/lib.rs b/src/lib.rs
index ae5f6d6e6f..9750430b2b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -11,6 +11,8 @@
 #![feature(abi_x86_interrupt)]
 #![feature(allocator_api)]
 #![feature(asm)]
+#![feature(asm_const)]
+#![feature(asm_sym)]
 #![feature(const_btree_new)]
 #![feature(const_fn_trait_bound)]
 #![feature(const_mut_refs)]

From e13eaaaf1992f79ad7e1941d70522de1d5264e9a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?= <mkroening@posteo.net>
Date: Sun, 5 Dec 2021 01:08:06 +0100
Subject: [PATCH 4/4] Upgrade toolchain channel to nightly-2021-12-04

---
 rust-toolchain.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index cf9f83138f..36d415aa2c 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,5 +1,5 @@
 [toolchain]
-channel = "nightly-2021-11-08"
+channel = "nightly-2021-12-04"
 components = [
     "rust-src",
     "llvm-tools-preview",