Merge remote-tracking branch 'remotes/bonzini-gitlab/tags/for-upstream' into staging

* configure and meson cleanups
* KVM_GET/SET_SREGS2 support for x86

# gpg: Signature made Wed 12 Jan 2022 13:09:19 GMT
# gpg:                using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg:                issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini-gitlab/tags/for-upstream:
  meson: reenable filemonitor-inotify compilation
  meson: build all modules by default
  configure: do not create roms/seabios/config.mak if SeaBIOS not present
  tests/tcg: Fix target-specific Makefile variables path for user-mode
  KVM: x86: ignore interrupt_bitmap field of KVM_GET/SET_SREGS
  KVM: use KVM_{GET|SET}_SREGS2 when supported.
  meson: add comments in the target-specific flags section
  configure, meson: move config-poison.h to meson
  meson: build contrib/ executables after generated headers
  configure: move non-command-line variables away from command-line parsing section
  configure: parse --enable/--disable-strip automatically, flip default
  configure, makefile: remove traces of really old files
  configure: do not set bsd_user/linux_user early
  configure: simplify creation of plugin symbol list
  block/file-posix: Simplify the XFS_IOC_DIOINFO handling
  meson: cleanup common-user/ build
  user: move common-user includes to a subdirectory of {bsd,linux}-user/
  meson: reuse common_user_inc when building files specific to user-mode emulators

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

1 files changed, 98 insertions, 0 deletions

diff --git a/linux-user/include/host/s390/host-signal.h b/linux-user/include/host/s390/host-signal.h
new file mode 100644
index 0000000000..a524f2ab00
--- /dev/null
+++ b/linux-user/include/host/s390/host-signal.h
@@ -0,0 +1,98 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (c) 2003-2005 Fabrice Bellard
+ * Copyright (c) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef S390_HOST_SIGNAL_H
+#define S390_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+    return uc->uc_mcontext.psw.addr;
+}
+
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.psw.addr = pc;
+}
+
+static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
+{
+    uint16_t *pinsn = (uint16_t *)host_signal_pc(uc);
+
+    /*
+     * ??? On linux, the non-rt signal handler has 4 (!) arguments instead
+     * of the normal 2 arguments.  The 4th argument contains the "Translation-
+     * Exception Identification for DAT Exceptions" from the hardware (aka
+     * "int_parm_long"), which does in fact contain the is_write value.
+     * The rt signal handler, as far as I can tell, does not give this value
+     * at all.  Not that we could get to it from here even if it were.
+     * So fall back to parsing instructions.  Treat read-modify-write ones as
+     * writes, which is not fully correct, but for tracking self-modifying code
+     * this is better than treating them as reads.  Checking si_addr page flags
+     * might be a viable improvement, albeit a racy one.
+     */
+    /* ??? This is not even close to complete.  */
+    switch (pinsn[0] >> 8) {
+    case 0x50: /* ST */
+    case 0x42: /* STC */
+    case 0x40: /* STH */
+    case 0xba: /* CS */
+    case 0xbb: /* CDS */
+        return true;
+    case 0xc4: /* RIL format insns */
+        switch (pinsn[0] & 0xf) {
+        case 0xf: /* STRL */
+        case 0xb: /* STGRL */
+        case 0x7: /* STHRL */
+            return true;
+        }
+        break;
+    case 0xc8: /* SSF format insns */
+        switch (pinsn[0] & 0xf) {
+        case 0x2: /* CSST */
+            return true;
+        }
+        break;
+    case 0xe3: /* RXY format insns */
+        switch (pinsn[2] & 0xff) {
+        case 0x50: /* STY */
+        case 0x24: /* STG */
+        case 0x72: /* STCY */
+        case 0x70: /* STHY */
+        case 0x8e: /* STPQ */
+        case 0x3f: /* STRVH */
+        case 0x3e: /* STRV */
+        case 0x2f: /* STRVG */
+            return true;
+        }
+        break;
+    case 0xeb: /* RSY format insns */
+        switch (pinsn[2] & 0xff) {
+        case 0x14: /* CSY */
+        case 0x30: /* CSG */
+        case 0x31: /* CDSY */
+        case 0x3e: /* CDSG */
+        case 0xe4: /* LANG */
+        case 0xe6: /* LAOG */
+        case 0xe7: /* LAXG */
+        case 0xe8: /* LAAG */
+        case 0xea: /* LAALG */
+        case 0xf4: /* LAN */
+        case 0xf6: /* LAO */
+        case 0xf7: /* LAX */
+        case 0xfa: /* LAAL */
+        case 0xf8: /* LAA */
+            return true;
+        }
+        break;
+    }
+    return false;
+}
+
+#endif