Pull LoongArch updates from Huacai Chen:
- Allow usage of LSX/LASX in the kernel, and use them for
SIMD-optimized RAID5/RAID6 routines
- Add Loongson Binary Translation (LBT) extension support
- Add basic KGDB & KDB support
- Add building with kcov coverage
- Add KFENCE (Kernel Electric-Fence) support
- Add KASAN (Kernel Address Sanitizer) support
- Some bug fixes and other small changes
- Update the default config file
* tag 'loongarch-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (25 commits)
LoongArch: Update Loongson-3 default config file
LoongArch: Add KASAN (Kernel Address Sanitizer) support
LoongArch: Simplify the processing of jumping new kernel for KASLR
kasan: Add (pmd|pud)_init for LoongArch zero_(pud|p4d)_populate process
kasan: Add __HAVE_ARCH_SHADOW_MAP to support arch specific mapping
LoongArch: Add KFENCE (Kernel Electric-Fence) support
LoongArch: Get partial stack information when providing regs parameter
LoongArch: mm: Add page table mapped mode support for virt_to_page()
kfence: Defer the assignment of the local variable addr
LoongArch: Allow building with kcov coverage
LoongArch: Provide kaslr_offset() to get kernel offset
LoongArch: Add basic KGDB & KDB support
LoongArch: Add Loongson Binary Translation (LBT) extension support
raid6: Add LoongArch SIMD recovery implementation
raid6: Add LoongArch SIMD syndrome calculation
LoongArch: Add SIMD-optimized XOR routines
LoongArch: Allow usage of LSX/LASX in the kernel
LoongArch: Define symbol 'fault' as a local label in fpu.S
LoongArch: Adjust {copy, clear}_user exception handler behavior
LoongArch: Use static defined zero page rather than allocated
...
1/8 of kernel addresses reserved for shadow memory. But for LoongArch,
There are a lot of holes between different segments and valid address
space (256T available) is insufficient to map all these segments to kasan
shadow memory with the common formula provided by kasan core, saying
(addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
So LoongArch has a arch-specific mapping formula, different segments are
mapped individually, and only limited space lengths of these specific
segments are mapped to shadow.
At early boot stage the whole shadow region populated with just one
physical page (kasan_early_shadow_page). Later, this page is reused as
readonly zero shadow for some memory that kasan currently don't track.
After mapping the physical memory, pages for shadow memory are allocated
and mapped.
Functions like memset()/memcpy()/memmove() do a lot of memory accesses.
If bad pointer passed to one of these function it is important to be
caught. Compiler's instrumentation cannot do this since these functions
are written in assembly.
KASan replaces memory functions with manually instrumented variants.
Original functions declared as weak symbols so strong definitions in
mm/kasan/kasan.c could replace them. Original functions have aliases
with '__' prefix in names, so we could call non-instrumented variant
if needed.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
