1 files changed, 62 insertions, 0 deletions

diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index 62a66f38a913..cde9e766b5b4 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -9,12 +9,74 @@
 #include <errno.h>
 #include <signal.h>
 #include <strings.h>
+#include "as-layout.h"
+#include "kern_constants.h"
 #include "kern_util.h"
 #include "os.h"
 #include "sysdep/barrier.h"
 #include "sysdep/sigcontext.h"
+#include "task.h"
 #include "user.h"
 
+void (*sig_info[NSIG])(int, struct uml_pt_regs *) = {
+	[SIGTRAP]	= relay_signal,
+	[SIGFPE]	= relay_signal,
+	[SIGILL]	= relay_signal,
+	[SIGWINCH]	= winch,
+	[SIGBUS]	= bus_handler,
+	[SIGSEGV]	= segv_handler,
+	[SIGIO]		= sigio_handler,
+	[SIGVTALRM]	= timer_handler };
+
+static struct uml_pt_regs ksig_regs[UM_NR_CPUS];
+
+void sig_handler_common_skas(int sig, void *sc_ptr)
+{
+	struct sigcontext *sc = sc_ptr;
+	struct uml_pt_regs *r;
+	void (*handler)(int, struct uml_pt_regs *);
+	int save_user, save_errno = errno;
+
+	/*
+	 * This is done because to allow SIGSEGV to be delivered inside a SEGV
+	 * handler.  This can happen in copy_user, and if SEGV is disabled,
+	 * the process will die.
+	 * XXX Figure out why this is better than SA_NODEFER
+	 */
+	if (sig == SIGSEGV) {
+		change_sig(SIGSEGV, 1);
+		/*
+		 * For segfaults, we want the data from the
+		 * sigcontext.  In this case, we don't want to mangle
+		 * the process registers, so use a static set of
+		 * registers.  For other signals, the process
+		 * registers are OK.
+		 */
+		r = &ksig_regs[cpu()];
+		copy_sc(r, sc_ptr);
+	} else
+		r = TASK_REGS(get_current());
+
+	save_user = r->is_user;
+	r->is_user = 0;
+	if ((sig == SIGFPE) || (sig == SIGSEGV) || (sig == SIGBUS) ||
+	    (sig == SIGILL) || (sig == SIGTRAP))
+		GET_FAULTINFO_FROM_SC(r->faultinfo, sc);
+
+	change_sig(SIGUSR1, 1);
+
+	handler = sig_info[sig];
+
+	/* unblock SIGVTALRM, SIGIO if sig isn't IRQ signal */
+	if ((sig != SIGIO) && (sig != SIGWINCH) && (sig != SIGVTALRM))
+		unblock_signals();
+
+	handler(sig, r);
+
+	errno = save_errno;
+	r->is_user = save_user;
+}
+
 /* Copied from linux/compiler-gcc.h since we can't include it directly */
 #define barrier() __asm__ __volatile__("": : :"memory")