With commit 63dc68a8cf60cb110b147dab1704d990808b39e2, kernel can not
handle BUG() and BUG_ON() properly since get_user() returns false for
kernel code. Use __get_user() to skip unnecessary access_ok(). This
patch also make BRK_BUG code encoded in the TNE instruction.
Signed-off-by: Atsushi Nemoto <anemo@xxxxxxxxxxxxx>
---
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 7d76a85..56a770c 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -650,7 +650,7 @@ asmlinkage void do_bp(struct pt_regs *regs)
unsigned int opcode, bcode;
siginfo_t info;
- if (get_user(opcode, (unsigned int __user *) exception_epc(regs)))
+ if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
goto out_sigsegv;
/*
@@ -700,7 +700,7 @@ asmlinkage void do_tr(struct pt_regs *regs)
unsigned int opcode, tcode = 0;
siginfo_t info;
- if (get_user(opcode, (unsigned int __user *) exception_epc(regs)))
+ if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
goto out_sigsegv;
/* Immediate versions don't provide a code. */
diff --git a/include/asm-mips/bug.h b/include/asm-mips/bug.h
index 4d560a5..7eb63de 100644
--- a/include/asm-mips/bug.h
+++ b/include/asm-mips/bug.h
@@ -18,7 +18,8 @@ do { \
#define BUG_ON(condition) \
do { \
- __asm__ __volatile__("tne $0, %0" : : "r" (condition)); \
+ __asm__ __volatile__("tne $0, %0, %1" \
+ : : "r" (condition), "i" (BRK_BUG)); \
} while (0)
#define HAVE_ARCH_BUG_ON
