diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c index b5afbec1db59..6010750c90b4 100644 --- a/arch/sh/kernel/signal_32.c +++ b/arch/sh/kernel/signal_32.c @@ -40,6 +40,16 @@ struct fdpic_func_descriptor { unsigned long GOT; }; +/* + * The following define adds a 64 byte gap between the signal + * stack frame and previous contents of the stack. This allows + * frame unwinding in a function epilogue but only if a frame + * pointer is used in the function. This is necessary because + * current gcc compilers (<4.3) do not generate unwind info on + * SH for function epilogues. + */ +#define UNWINDGUARD 64 + /* * Atomically swap in the new signal mask, and wait for a signal. */ @@ -327,7 +337,7 @@ get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) sp = current->sas_ss_sp + current->sas_ss_size; } - return (void __user *)((sp - frame_size) & -8ul); + return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul); } /* These symbols are defined with the addresses in the vsyscall page.