Merge branch 'for-next/entry-s-to-c' into for-next/core

Move the synchronous exception paths from entry.S into a C file to
improve the code readability.

* for-next/entry-s-to-c:
  arm64: entry-common: don't touch daif before bp-hardening
  arm64: Remove asmlinkage from updated functions
  arm64: entry: convert el0_sync to C
  arm64: entry: convert el1_sync to C
  arm64: add local_daif_inherit()
  arm64: Add prototypes for functions called by entry.S
  arm64: remove __exception annotations

1 files changed, 13 insertions, 49 deletions

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 9fc6db0bcbad..7ae3a5bb8a53 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -32,7 +32,8 @@
 #include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/esr.h>
-#include <asm/kasan.h>
+#include <asm/kprobes.h>
+#include <asm/processor.h>
 #include <asm/sysreg.h>
 #include <asm/system_misc.h>
 #include <asm/pgtable.h>
@@ -101,18 +102,6 @@ static void mem_abort_decode(unsigned int esr)
 		data_abort_decode(esr);
 }
 
-static inline bool is_ttbr0_addr(unsigned long addr)
-{
-	/* entry assembly clears tags for TTBR0 addrs */
-	return addr < TASK_SIZE;
-}
-
-static inline bool is_ttbr1_addr(unsigned long addr)
-{
-	/* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */
-	return arch_kasan_reset_tag(addr) >= PAGE_OFFSET;
-}
-
 static inline unsigned long mm_to_pgd_phys(struct mm_struct *mm)
 {
 	/* Either init_pg_dir or swapper_pg_dir */
@@ -736,8 +725,7 @@ static const struct fault_info fault_info[] = {
 	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 63"			},
 };
 
-asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
-					 struct pt_regs *regs)
+void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
 	const struct fault_info *inf = esr_to_fault_info(esr);
 
@@ -753,43 +741,21 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
 	arm64_notify_die(inf->name, regs,
 			 inf->sig, inf->code, (void __user *)addr, esr);
 }
+NOKPROBE_SYMBOL(do_mem_abort);
 
-asmlinkage void __exception do_el0_irq_bp_hardening(void)
+void do_el0_irq_bp_hardening(void)
 {
 	/* PC has already been checked in entry.S */
 	arm64_apply_bp_hardening();
 }
+NOKPROBE_SYMBOL(do_el0_irq_bp_hardening);
 
-asmlinkage void __exception do_el0_ia_bp_hardening(unsigned long addr,
-						   unsigned int esr,
-						   struct pt_regs *regs)
-{
-	/*
-	 * We've taken an instruction abort from userspace and not yet
-	 * re-enabled IRQs. If the address is a kernel address, apply
-	 * BP hardening prior to enabling IRQs and pre-emption.
-	 */
-	if (!is_ttbr0_addr(addr))
-		arm64_apply_bp_hardening();
-
-	local_daif_restore(DAIF_PROCCTX);
-	do_mem_abort(addr, esr, regs);
-}
-
-
-asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
-					   unsigned int esr,
-					   struct pt_regs *regs)
+void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
-	if (user_mode(regs)) {
-		if (!is_ttbr0_addr(instruction_pointer(regs)))
-			arm64_apply_bp_hardening();
-		local_daif_restore(DAIF_PROCCTX);
-	}
-
 	arm64_notify_die("SP/PC alignment exception", regs,
 			 SIGBUS, BUS_ADRALN, (void __user *)addr, esr);
 }
+NOKPROBE_SYMBOL(do_sp_pc_abort);
 
 int __init early_brk64(unsigned long addr, unsigned int esr,
 		       struct pt_regs *regs);
@@ -872,8 +838,7 @@ NOKPROBE_SYMBOL(debug_exception_exit);
 #ifdef CONFIG_ARM64_ERRATUM_1463225
 DECLARE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa);
 
-static int __exception
-cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
 {
 	if (user_mode(regs))
 		return 0;
@@ -892,16 +857,15 @@ cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
 	return 1;
 }
 #else
-static int __exception
-cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
 {
 	return 0;
 }
 #endif /* CONFIG_ARM64_ERRATUM_1463225 */
+NOKPROBE_SYMBOL(cortex_a76_erratum_1463225_debug_handler);
 
-asmlinkage void __exception do_debug_exception(unsigned long addr_if_watchpoint,
-					       unsigned int esr,
-					       struct pt_regs *regs)
+void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr,
+			struct pt_regs *regs)
 {
 	const struct fault_info *inf = esr_to_debug_fault_info(esr);
 	unsigned long pc = instruction_pointer(regs);