dyld: remove KERNEL_EXIDX_START/END globals, move dl_unwind_find_exidx() into runtime::kernel::core1

Gitea issue #16
This commit is contained in:
Astro 2020-07-27 19:54:53 +02:00
parent 641204425e
commit b388b529ad
3 changed files with 51 additions and 43 deletions

View File

@ -4,7 +4,7 @@ extern crate alloc;
extern crate log; extern crate log;
extern crate libcortex_a9; extern crate libcortex_a9;
use core::{convert, fmt, str}; use core::{convert, fmt, ops::Range, str};
use alloc::string::String; use alloc::string::String;
use log::{debug, trace}; use log::{debug, trace};
use elf::*; use elf::*;
@ -58,44 +58,11 @@ fn elf_hash(name: &[u8]) -> u32 {
h h
} }
// linker symbols
extern "C" {
#[no_mangle]
static __text_start: u32;
#[no_mangle]
static __text_end: u32;
#[no_mangle]
static __exidx_start: u32;
#[no_mangle]
static __exidx_end: u32;
}
static mut KERNEL_EXIDX_START: u32 = 0;
static mut KERNEL_EXIDX_END: u32 = 0;
#[no_mangle]
extern fn dl_unwind_find_exidx(pc: u32, len_ptr: *mut u32) -> u32 {
let length: u32;
let start: u32;
unsafe {
if (&__text_start as *const u32 as u32) <= pc && pc < (&__text_end as *const u32 as u32) {
length = (&__exidx_end - &__exidx_start) as u32;
start = &__exidx_start as *const u32 as u32;
} else {
// make sure that the kernel is loaded
assert_ne!(KERNEL_EXIDX_START, 0);
length = (KERNEL_EXIDX_END - KERNEL_EXIDX_START) / core::mem::size_of::<u32>() as u32;
start = KERNEL_EXIDX_START;
}
*len_ptr = length;
}
start
}
pub struct Library { pub struct Library {
pub image: Image, pub image: Image,
pub arch: Arch, pub arch: Arch,
dyn_section: DynamicSection, dyn_section: DynamicSection,
exidx: Range<usize>,
} }
impl Library { impl Library {
@ -170,6 +137,10 @@ impl Library {
pub fn rebind(&self, name: &[u8], addr: *const ()) -> Result<(), Error> { pub fn rebind(&self, name: &[u8], addr: *const ()) -> Result<(), Error> {
reloc::rebind(self.arch, self, name, addr as Elf32_Word) reloc::rebind(self.arch, self, name, addr as Elf32_Word)
} }
pub fn exidx(&self) -> &[u32] {
self.image.get_ref_slice_unchecked(&self.exidx)
}
} }
pub fn load( pub fn load(
@ -226,18 +197,17 @@ pub fn load(
} }
} }
let mut exidx = None;
// Obtain EXIDX // Obtain EXIDX
for shdr in file.section_headers() { for shdr in file.section_headers() {
let shdr = shdr.ok_or("cannot read section header")?; let shdr = shdr.ok_or("cannot read section header")?;
match shdr.sh_type as usize { match shdr.sh_type as usize {
SHT_ARM_EXIDX => { SHT_ARM_EXIDX => {
let slice = image.get(shdr.sh_addr as usize.. let range = shdr.sh_addr as usize..
(shdr.sh_addr + shdr.sh_size) as usize) (shdr.sh_addr + shdr.sh_size) as usize;
.ok_or("section header requests an out of bounds load (in target)")?; let _ = image.get(range.clone())
unsafe { .ok_or("section header specifies EXIDX outside of image (in target)")?;
KERNEL_EXIDX_START = slice.as_ptr() as u32; exidx = Some(range);
KERNEL_EXIDX_END = slice.as_ptr().add(slice.len()) as u32;
}
} }
_ => {} _ => {}
} }
@ -252,7 +222,8 @@ pub fn load(
let lib = Library { let lib = Library {
arch, arch,
image, image,
dyn_section dyn_section,
exidx: exidx.ok_or("no EXIDX section")?,
}; };
for rela in lib.rela() { for rela in lib.rela() {

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@ -22,6 +22,18 @@ use super::{
cache cache
}; };
// linker symbols
extern "C" {
#[no_mangle]
static __text_start: u32;
#[no_mangle]
static __text_end: u32;
#[no_mangle]
static __exidx_start: u32;
#[no_mangle]
static __exidx_end: u32;
}
unsafe fn attribute_writeback(typeinfo: *const ()) { unsafe fn attribute_writeback(typeinfo: *const ()) {
struct Attr { struct Attr {
offset: usize, offset: usize,
@ -205,3 +217,27 @@ pub fn terminate(exception: &'static eh_artiq::Exception<'static>, backtrace: &'
error!("Core1 uncaught exception"); error!("Core1 uncaught exception");
loop {} loop {}
} }
/// Called by llvm_libunwind
#[no_mangle]
extern fn dl_unwind_find_exidx(pc: *const u32, len_ptr: *mut u32) -> *const u32 {
let exidx = unsafe {
KERNEL_IMAGE.as_ref()
.expect("dl_unwind_find_exidx kernel image")
.library.get().as_ref().unwrap().exidx()
};
let length;
let start: *const u32;
unsafe {
if &__text_start as *const u32 <= pc && pc < &__text_end as *const u32 {
length = (&__exidx_end as *const u32).offset_from(&__exidx_start) as u32;
start = &__exidx_start;
} else {
length = exidx.len() as u32;
start = exidx.as_ptr();
}
*len_ptr = length;
}
start
}

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@ -5,6 +5,7 @@
#![feature(panic_info_message)] #![feature(panic_info_message)]
#![feature(c_variadic)] #![feature(c_variadic)]
#![feature(const_btree_new)] #![feature(const_btree_new)]
#![feature(ptr_offset_from)]
extern crate alloc; extern crate alloc;