apply changes from rpi-6.6.y-coreforge-amdgpu, plus new patches, to rpi-6.12.y

Author: nicholasaiello

arch/arm64/Kconfig

@@ -1694,6 +1694,14 @@ config ARM64_TAGGED_ADDR_ABI
 	  to system calls as pointer arguments. For details, see
 	  Documentation/arch/arm64/tagged-address-abi.rst.
 
+config ARM64_ALIGNMENT_FIXUPS
+    bool "Fix up misaligned loads and stores from userspace for 64bit code"
+    default n
+    help
+      Userspace may incorrectly assume that certain memory does not need
+      any special alignment considerations, which may result in Bus Erros.
+      Enable to handle these faults in the kernel.
+
 menuconfig COMPAT
 	bool "Kernel support for 32-bit EL0"
 	depends on ARM64_4K_PAGES || EXPERT

arch/arm64/include/asm/exception.h

@@ -68,6 +68,7 @@ void do_sp_pc_abort(unsigned long addr, unsigned long esr, struct pt_regs *regs)
 void bad_el0_sync(struct pt_regs *regs, int reason, unsigned long esr);
 void do_el0_cp15(unsigned long esr, struct pt_regs *regs);
 int do_compat_alignment_fixup(unsigned long addr, struct pt_regs *regs);
+int do_alignment_fixup(unsigned long addr, struct pt_regs *regs);
 void do_el0_svc(struct pt_regs *regs);
 void do_el0_svc_compat(struct pt_regs *regs);
 void do_el0_fpac(struct pt_regs *regs, unsigned long esr);

arch/arm64/kernel/Makefile

@@ -39,6 +39,7 @@ obj-$(CONFIG_COMPAT)			+= sys32.o signal32.o			\
 					   sys_compat.o
 obj-$(CONFIG_COMPAT)			+= sigreturn32.o
 obj-$(CONFIG_COMPAT_ALIGNMENT_FIXUPS)	+= compat_alignment.o
+obj-$(CONFIG_ARM64_ALIGNMENT_FIXUPS)	+= compat_alignment_64.o
 obj-$(CONFIG_KUSER_HELPERS)		+= kuser32.o
 obj-$(CONFIG_FUNCTION_TRACER)		+= ftrace.o entry-ftrace.o
 obj-$(CONFIG_MODULES)			+= module.o module-plts.o

arch/arm64/kernel/compat_alignment.c

@@ -318,7 +318,6 @@ int do_compat_alignment_fixup(unsigned long addr, struct pt_regs *regs)
 	int thumb2_32b = 0;
 
 	instrptr = instruction_pointer(regs);
-
 	if (compat_thumb_mode(regs)) {
 		__le16 __user *ptr = (__le16 __user *)(instrptr & ~1);
 		u16 tinstr, tinst2;