fix: Leave .bss initialization of loader to firmware

Overriding the own bss after load is problematic if items are already in use. The firmware that loads and jumps into the loader should zero the .bss already. Signed-off-by: Martin Kröning <[email protected]>
hermit-os · Aug 10, 2023 · 0ea9038 · 0ea9038
1 parent c03ecd0
commit 0ea9038
Show file tree

Hide file tree

Showing 4 changed files with 0 additions and 21 deletions.
diff --git a/src/arch/aarch64/link.ld b/src/arch/aarch64/link.ld
@@ -36,10 +36,8 @@ SECTIONS
     *(.data.*)
   } :segment_rw
   .bss    : ALIGN(8) {
-    bss_start = .;
     *(.bss)
     *(.bss.*)
-    bss_end = .;
   } :segment_rw
   . = ALIGN(4K); /* Align to page boundary */
   /***********************************************************************************************

diff --git a/src/arch/x86_64/link.ld b/src/arch/x86_64/link.ld
@@ -22,10 +22,8 @@ SECTIONS
     *(.data.*)
   }
   .bss ALIGN(4096) : AT(ADDR(.bss)) {
-    bss_start = .;
     *(.bss)
     *(.bss.*)
   }
-  bss_end = .;
   kernel_end = .;
 }
diff --git a/src/arch/x86_64/link_fc.ld b/src/arch/x86_64/link_fc.ld
@@ -21,10 +21,8 @@ SECTIONS
     *(.data.*)
   }
   .bss ALIGN(4096) : AT(ADDR(.bss)) {
-    bss_start = .;
     *(.bss)
     *(.bss.*)
   }
-  bss_end = .;
   kernel_end = .;
 }
diff --git a/src/none.rs b/src/none.rs
@@ -1,6 +1,5 @@
 use core::fmt::Write;
 use core::mem::MaybeUninit;
-use core::ptr::addr_of_mut;
 use core::slice;
 
 use hermit_entry::elf::KernelObject;
@@ -17,7 +16,6 @@ extern "C" {
 /// (called from entry.asm or entry.rs)
 #[no_mangle]
 unsafe extern "C" fn loader_main() -> ! {
-	init_bss();
 	arch::message_output_init();
 	crate::log::init();
 
@@ -38,19 +36,6 @@ unsafe extern "C" fn loader_main() -> ! {
 	arch::boot_kernel(kernel_info)
 }
 
-unsafe fn init_bss() {
-	extern "C" {
-		static mut bss_start: MaybeUninit<u8>;
-		static mut bss_end: MaybeUninit<u8>;
-	}
-
-	let start_ptr = addr_of_mut!(bss_start);
-	let end_ptr = addr_of_mut!(bss_end);
-	let len = end_ptr.offset_from(start_ptr).try_into().unwrap();
-	let slice = slice::from_raw_parts_mut(start_ptr, len);
-	slice.fill(MaybeUninit::new(0));
-}
-
 #[panic_handler]
 fn panic(info: &core::panic::PanicInfo<'_>) -> ! {
 	// We can't use `println!` or related macros, because `_print` unwraps a result and might panic again