Commit 408b1d3c authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: add trap handler for division by zero 



Add c-level handler for the division by zero exception and kill the task
if it was thrown from the kernel space or send SIGFPE otherwise.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent b011946d

arch/xtensa/kernel/traps.c

+7 −1
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ 
 */



static void do_illegal_instruction(struct pt_regs *regs);

static void do_div0(struct pt_regs *regs);

static void do_interrupt(struct pt_regs *regs);

#if XTENSA_FAKE_NMI

static void do_nmi(struct pt_regs *regs);
@@ -95,7 +96,7 @@ static dispatch_init_table_t __initdata dispatch_init_table[] = { 
#ifdef SUPPORT_WINDOWED

{ EXCCAUSE_ALLOCA,		USER|KRNL, fast_alloca },

#endif

/* EXCCAUSE_INTEGER_DIVIDE_BY_ZERO unhandled */

{ EXCCAUSE_INTEGER_DIVIDE_BY_ZERO, 0,	   do_div0 },

/* EXCCAUSE_PRIVILEGED unhandled */

#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION

#ifdef CONFIG_XTENSA_UNALIGNED_USER
@@ -307,6 +308,11 @@ static void do_illegal_instruction(struct pt_regs *regs) 
	force_sig(SIGILL);

}



static void do_div0(struct pt_regs *regs)

{

	__die_if_kernel("Unhandled division by 0 in kernel", regs, SIGKILL);

	force_sig_fault(SIGFPE, FPE_INTDIV, (void __user *)regs->pc);

}



/*

 * Handle unaligned memory accesses from user space. Kill task.