Merge remote-tracking branch 'remotes/rth-gitlab/tags/pull-tcg-20220211' into staging

Fix safe_syscall_base for sparc64.
Fix host signal handling for sparc64-linux.
Speedups for jump cache and work list probing.
Fix for exception replays.
Raise guest SIGBUS for user-only misaligned accesses.

# gpg: Signature made Fri 11 Feb 2022 01:27:16 GMT
# gpg:                using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg:                issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth-gitlab/tags/pull-tcg-20220211: (34 commits)
  tests/tcg/multiarch: Add sigbus.c
  tcg/sparc: Support unaligned access for user-only
  tcg/sparc: Add tcg_out_jmpl_const for better tail calls
  tcg/sparc: Use the constant pool for 64-bit constants
  tcg/sparc: Convert patch_reloc to return bool
  tcg/sparc: Improve code gen for shifted 32-bit constants
  tcg/sparc: Add scratch argument to tcg_out_movi_int
  tcg/sparc: Split out tcg_out_movi_imm32
  tcg/sparc: Use tcg_out_movi_imm13 in tcg_out_addsub2_i64
  tcg/mips: Support unaligned access for softmmu
  tcg/mips: Support unaligned access for user-only
  tcg/arm: Support raising sigbus for user-only
  tcg/arm: Reserve a register for guest_base
  tcg/arm: Support unaligned access for softmmu
  tcg/arm: Check alignment for ldrd and strd
  tcg/arm: Remove use_armv6_instructions
  tcg/arm: Remove use_armv5t_instructions
  tcg/arm: Drop support for armv4 and armv5 hosts
  tcg/loongarch64: Support raising sigbus for user-only
  tcg/tci: Support raising sigbus for user-only
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 10 insertions, 12 deletions

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 32854bb375..27a0ff30e9 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -800,7 +800,7 @@ void queue_signal(CPUArchState *env, int sig, int si_type,
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    ucontext_t *uc = (ucontext_t *)puc;
+    host_sigcontext *uc = (host_sigcontext *)puc;
     uintptr_t pcreg = host_signal_pc(uc);
 
     if (pcreg > (uintptr_t)safe_syscall_start
@@ -815,11 +815,12 @@ static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
     CPUState *cpu = env_cpu(env);
     TaskState *ts = cpu->opaque;
     target_siginfo_t tinfo;
-    ucontext_t *uc = puc;
+    host_sigcontext *uc = puc;
     struct emulated_sigtable *k;
     int guest_sig;
     uintptr_t pc = 0;
     bool sync_sig = false;
+    void *sigmask = host_signal_mask(uc);
 
     /*
      * Non-spoofed SIGSEGV and SIGBUS are synchronous, and need special
@@ -849,8 +850,7 @@ static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
             if (info->si_code == SEGV_ACCERR && h2g_valid(host_addr)) {
                 /* If this was a write to a TB protected page, restart. */
                 if (is_write &&
-                    handle_sigsegv_accerr_write(cpu, &uc->uc_sigmask,
-                                                pc, guest_addr)) {
+                    handle_sigsegv_accerr_write(cpu, sigmask, pc, guest_addr)) {
                     return;
                 }
 
@@ -865,10 +865,10 @@ static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
                 }
             }
 
-            sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
+            sigprocmask(SIG_SETMASK, sigmask, NULL);
             cpu_loop_exit_sigsegv(cpu, guest_addr, access_type, maperr, pc);
         } else {
-            sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
+            sigprocmask(SIG_SETMASK, sigmask, NULL);
             if (info->si_code == BUS_ADRALN) {
                 cpu_loop_exit_sigbus(cpu, guest_addr, access_type, pc);
             }
@@ -909,17 +909,15 @@ static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
      * now and it getting out to the main loop. Signals will be
      * unblocked again in process_pending_signals().
      *
-     * WARNING: we cannot use sigfillset() here because the uc_sigmask
+     * WARNING: we cannot use sigfillset() here because the sigmask
      * field is a kernel sigset_t, which is much smaller than the
      * libc sigset_t which sigfillset() operates on. Using sigfillset()
      * would write 0xff bytes off the end of the structure and trash
      * data on the struct.
-     * We can't use sizeof(uc->uc_sigmask) either, because the libc
-     * headers define the struct field with the wrong (too large) type.
      */
-    memset(&uc->uc_sigmask, 0xff, SIGSET_T_SIZE);
-    sigdelset(&uc->uc_sigmask, SIGSEGV);
-    sigdelset(&uc->uc_sigmask, SIGBUS);
+    memset(sigmask, 0xff, SIGSET_T_SIZE);
+    sigdelset(sigmask, SIGSEGV);
+    sigdelset(sigmask, SIGBUS);
 
     /* interrupt the virtual CPU as soon as possible */
     cpu_exit(thread_cpu);