commit 31efaef1d9b80b7803e22ef28ffc51df04db60ab
author Peter Maydell <peter.maydell@linaro.org> Wed Jul 06 15:09:29 2016 +0100
committer Riku Voipio <riku.voipio@linaro.org> Tue Jul 19 15:23:16 2016 +0300
tree d46156d7a59537b364e30aa6365e40e1c85f4630
parent f2c2fb50be13aca9c449d9156817c915d9cd2acb

linux-user: Forget about synchronous signal once it is delivered

Commit 655ed67c2a248cf which switched synchronous signals to
benig recorded in ts->sync_signal rather than in a queue
with every other signal had a bug: we failed to clear
the flag indicating that a synchronous signal was pending
when we delivered it. This meant that we would take the signal
again and again every time the guest made a syscall.
(This is a bug introduced in my refactoring of Timothy Baldwin's
original code.)

Fix this by passing in the struct emulated_sigtable* to
handle_pending_signal(), so that we clear the pending flag
in the ts->sync_signal struct when handling a synchronous signal.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

linux-user/signal.c

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 9d98045..9a4d894 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -5826,7 +5826,8 @@
 
 #endif
 
-static void handle_pending_signal(CPUArchState *cpu_env, int sig)
+static void handle_pending_signal(CPUArchState *cpu_env, int sig,
+                                  struct emulated_sigtable *k)
 {
     CPUState *cpu = ENV_GET_CPU(cpu_env);
     abi_ulong handler;
@@ -5834,7 +5835,6 @@
     target_sigset_t target_old_set;
     struct target_sigaction *sa;
     TaskState *ts = cpu->opaque;
-    struct emulated_sigtable *k = &ts->sigtab[sig - 1];
 
     trace_user_handle_signal(cpu_env, sig);
     /* dequeue signal */
@@ -5937,7 +5937,7 @@
                 sigact_table[sig - 1]._sa_handler = TARGET_SIG_DFL;
             }
 
-            handle_pending_signal(cpu_env, sig);
+            handle_pending_signal(cpu_env, sig, &ts->sync_signal);
         }
 
         for (sig = 1; sig <= TARGET_NSIG; sig++) {
@@ -5947,7 +5947,7 @@
             if (ts->sigtab[sig - 1].pending &&
                 (!sigismember(blocked_set,
                               target_to_host_signal_table[sig]))) {
-                handle_pending_signal(cpu_env, sig);
+                handle_pending_signal(cpu_env, sig, &ts->sigtab[sig - 1]);
                 /* Restart scan from the beginning */
                 sig = 1;
             }