Implement a generic access rights modification procedure instead
of the procedures that only do one thing (enable/disable write)
to one section (text).
When the .elf file is loaded from disk, the kernel must be given write
access to the allocated .text section in the task's address environment.
The access is removed after the elf is loaded and relocations are done.
NOTE:
The reason this works for the ARM implementation, is that the ARM MMU
can be configured to give write access for the privileged mode, but
revoke write access for the user mode.
Regardless, it would be smart to revoke write access even for the
kernel, when the kernel does not need it. This framework allows doing
that, if someone wishes to take up the task.
Basically, mirror the following two commits from modlib.
It's shame we have two copies of elf loaders.
```
commit 51490bad55
Author: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Wed Apr 14 17:07:39 2021 +0900
modlib: Implement sh_addralign handling
I've seen a module with 16 bytes .rodata alignment for xmm operations.
It was getting SEGV on sim/Linux because of the alignment issue.
The same module binary seems working fine after applying this patch.
Also, tested on sim/macOS and esp32 on qemu,
using a module with an artificially large alignment. (64 bytes)
```
```
commit 418e11b8b3
Author: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Thu Apr 15 11:33:48 2021 +0900
modlib: Always use separate allocation for text and data
Pros:
* Reduce code differences
* Smaller allocations for !CONFIG_ARCH_USE_MODULE_TEXT
Cons:
* Likely to use more memory for !CONFIG_ARCH_USE_MODULE_TEXT in total
Tested with:
* sim:module on macOS
* esp32-devkit:nsh + CONFIG_MODULE on qemu
* lm3s6965-ek:qemu-protected + CONFIG_EXAMPLES_SOTEST on qemu
```
Summary:
- This commit introduces a separate text memory for ELF
- The logic is similar to modlib
Impact:
- None
Testing:
- Tested with spresense:elf
- NOTE: needs separate commits
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
to avoid close the same handle twice because
the caller also call elf_uninit in this case
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: Iddcbae9587d11d3b5b06e876d4a037ac0d11992e
When CONFIG_SYMTAB_ORDEREDBYNAME is selected most code will use
the ordered search function. When it is not selected no code will
use the ordered search function. This change merges the two
functions and varies its behaviour based on the config setting,
such that all callers can simply call the one search function
and get the best behaviour.
An additional configuration option allows leading underscores to
be stripped from symbols being relocated in loaded objects. This
allows toolchains which prefix C symbol with underscores to make
loadable ELF objects.
since other arch has the different unwind approach
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: Icefa0d4bc31bff967372949216d337770cd7e768
* The appropriate size of stack varies among archs.
E.g. for 64-bit sim, 2048 is way too small, especially when the task
happens to use host OS functionalities.
I plan to allow an arch provide its own default.
* I plan to use this to replace hardcoded "STACKSIZE = 2048" in APPDIR.
* include: Introduce elf64.h and elf.h
Added elf64.h for 64bit ELF support and moved common definitions
from elf32.h to elf.h. Also introduced Elf_xxx to be used in
common libraries such as binfmt.
* binfmt, include, modlib, module: Add support for ELF64
Elf_xxx must be used instead of Elf32_xxx to support ELF64.
To use ELF64, CONFIG_ELF_64BIT must be enabled.
* binfmt, modlib: Add support for relocate address
* arch: risc-v: Add include/elf.h
* libs: machine: Add risc-v related files.
NOTE: Currently only supports ELF64
* boards: maix-bit: Add elf and posix_spawn configurations
* boards: maix-bit: Add support for module configuration
* fix warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'long unsigned int'
* fix warning: implicit declaration of function 'up_init_exidx'
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
