If we directly compile the switch.S file into the kernel, the address of
the kvm_exc_entry function will definitely be within the DMW memory area.
Therefore, we will no longer need to perform a copy relocation of the
kvm_exc_entry.

So this patch compiles switch.S directly into the kernel, and then remove
the copy relocation execution logic for the kvm_exc_entry function.

Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

The custom definition is identical to the generic fallback one.

So remove it.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

The SYM_SIGFUNC_START definition should match sigcontext that the length
of GPRs are 8 bytes for both 32BIT and 64BIT. So replace SZREG with 8 to
fix it.

Cc: stable@vger.kernel.org
Fixes: e4878c37f6679fde ("LoongArch: vDSO: Emit GNU_EH_FRAME correctly")
Suggested-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Pull LoongArch updates from Huacai Chen:

 - Adjust build infrastructure for 32BIT/64BIT

 - Add HIGHMEM (PKMAP and FIX_KMAP) support

 - Show and handle CPU vulnerabilites correctly

 - Batch the icache maintenance for jump_label

 - Add more atomic instructions support for BPF JIT

 - Add more features (e.g. fsession) support for BPF trampoline

 - Some bug fixes and other small changes

* tag 'loongarch-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (21 commits)
  selftests/bpf: Enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch
  LoongArch: BPF: Add fsession support for trampolines
  LoongArch: BPF: Introduce emit_store_stack_imm64() helper
  LoongArch: BPF: Support up to 12 function arguments for trampoline
  LoongArch: BPF: Support small struct arguments for trampoline
  LoongArch: BPF: Open code and remove invoke_bpf_mod_ret()
  LoongArch: BPF: Support load-acquire and store-release instructions
  LoongArch: BPF: Support 8 and 16 bit read-modify-write instructions
  LoongArch: BPF: Add the default case in emit_atomic() and rename it
  LoongArch: Define instruction formats for AM{SWAP/ADD}.{B/H} and DBAR
  LoongArch: Batch the icache maintenance for jump_label
  LoongArch: Add flush_icache_all()/local_flush_icache_all()
  LoongArch: Add spectre boundry for syscall dispatch table
  LoongArch: Show CPU vulnerabilites correctly
  LoongArch: Make arch_irq_work_has_interrupt() true only if IPI HW exist
  LoongArch: Use get_random_canary() for stack canary init
  LoongArch: Improve the logging of disabling KASLR
  LoongArch: Align FPU register state to 32 bytes
  LoongArch: Handle CONFIG_32BIT in syscall_get_arch()
  LoongArch: Add HIGHMEM (PKMAP and FIX_KMAP) support
  ...

The 8 and 16 bit read-modify-write atomic instructions amadd.{b/h} and
amswap.{b/h} were newly added in the latest LoongArch Reference Manual,
define the instruction format and check whether support via CPUCFG.

Furthermore, define the instruction format for DBAR which will be used
to support BPF load-acquire and store-release instructions.

This is preparation for later patches.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Switch to the batched version of the jump label update functions so
instruction cache maintenance is deferred until the end of the update.

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch maintains ICache/DCache coherency by hardware, so we just need
"ibar 0" to avoid instruction hazard here.

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

After commit 7c405fb3279b3924 ("rcu: Use an intermediate irq_work to
start process_srcu()"), Loongson-2K0300/2K0500 fail to boot. Because
IRQ_WORK need IPI but Loongson-2K0300/2K0500 don't have IPI HW.

So make arch_irq_work_has_interrupt() return true only if IPI HW exist.

Cc: stable@vger.kernel.org
Reported-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Like others, replace the custom stack canary initialization with the
get_random_canary() helper, following the pattern established in commit
622754e84b10 ("stackprotector: actually use get_random_canary()").

Signed-off-by: Luo Qiu <luoqiu@kylinsec.com.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Move fpr to the beginning of struct loongarch_fpu so it is naturally
aligned to FPU_ALIGN (32 bytes), improving 256-bit SIMD (LASX) context
switch performance.

Also adjust process.c and fpu.S to work well with the new loongarch_fpu
layout.

Signed-off-by: Lisa Robinson <lisa@bytefly.space>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>