Merge remote-tracking branch 'remotes/vivier/tags/linux-user-for-6.2-pull-request' into staging

Pull request linux-user 20211004

Move signal trampolines to new page

# gpg: Signature made Mon 04 Oct 2021 12:43:53 AM PDT
# gpg:                using RSA key CD2F75DDC8E3A4DC2E4F5173F30C38BD3F2FBE3C
# gpg:                issuer "laurent@vivier.eu"
# gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>" [full]
# gpg:                 aka "Laurent Vivier <laurent@vivier.eu>" [full]
# gpg:                 aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>" [full]

* remotes/vivier/tags/linux-user-for-6.2-pull-request: (26 commits)
  tests/tcg/multiarch: Re-enable signals test for most guests
  linux-user: Remove default for TARGET_ARCH_HAS_SIGTRAMP_PAGE
  linux-user/xtensa: Implement setup_sigtramp
  linux-user/sparc: Implement setup_sigtramp
  linux-user/sh4: Implement setup_sigtramp
  linux-user/s390x: Implement setup_sigtramp
  linux-user/riscv: Implement setup_sigtramp
  linux-user/ppc: Implement setup_sigtramp
  linux-user/ppc: Simplify encode_trampoline
  linux-user/openrisc: Implement setup_sigtramp
  linux-user/nios2: Document non-use of setup_sigtramp
  linux-user/mips: Implement setup_sigtramp
  linux-user/mips: Tidy install_sigtramp
  linux-user/microblaze: Implement setup_sigtramp
  linux-user/m68k: Implement setup_sigtramp
  linux-user/x86_64: Raise SIGSEGV if SA_RESTORER not set
  linux-user/i386: Implement setup_sigtramp
  linux-user/hppa: Document non-use of setup_sigtramp
  linux-user/hexagon: Implement setup_sigtramp
  linux-user/cris: Implement setup_sigtramp
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

2 files changed, 16 insertions, 8 deletions

diff --git a/linux-user/openrisc/signal.c b/linux-user/openrisc/signal.c
index ca2532bf50..be8b68784a 100644
--- a/linux-user/openrisc/signal.c
+++ b/linux-user/openrisc/signal.c
@@ -38,7 +38,6 @@ typedef struct target_ucontext {
 typedef struct target_rt_sigframe {
     struct target_siginfo info;
     target_ucontext uc;
-    uint32_t retcode[4];  /* trampoline code */
 } target_rt_sigframe;
 
 static void restore_sigcontext(CPUOpenRISCState *env, target_sigcontext *sc)
@@ -116,14 +115,8 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
         __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
     }
 
-    /* This is l.ori r11,r0,__NR_sigreturn; l.sys 1; l.nop; l.nop */
-    __put_user(0xa9600000 | TARGET_NR_rt_sigreturn, frame->retcode + 0);
-    __put_user(0x20000001, frame->retcode + 1);
-    __put_user(0x15000000, frame->retcode + 2);
-    __put_user(0x15000000, frame->retcode + 3);
-
     /* Set up registers for signal handler */
-    cpu_set_gpr(env, 9, frame_addr + offsetof(target_rt_sigframe, retcode));
+    cpu_set_gpr(env, 9, default_rt_sigreturn);
     cpu_set_gpr(env, 3, sig);
     cpu_set_gpr(env, 4, frame_addr + offsetof(target_rt_sigframe, info));
     cpu_set_gpr(env, 5, frame_addr + offsetof(target_rt_sigframe, uc));
@@ -169,3 +162,16 @@ long do_rt_sigreturn(CPUOpenRISCState *env)
     force_sig(TARGET_SIGSEGV);
     return 0;
 }
+
+void setup_sigtramp(abi_ulong sigtramp_page)
+{
+    uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 8, 0);
+    assert(tramp != NULL);
+
+    /* This is l.ori r11,r0,__NR_sigreturn; l.sys 1 */
+    __put_user(0xa9600000 | TARGET_NR_rt_sigreturn, tramp + 0);
+    __put_user(0x20000001, tramp + 1);
+
+    default_rt_sigreturn = sigtramp_page;
+    unlock_user(tramp, sigtramp_page, 8);
+}
diff --git a/linux-user/openrisc/target_signal.h b/linux-user/openrisc/target_signal.h
index 8283eaf544..077ec3d5e8 100644
--- a/linux-user/openrisc/target_signal.h
+++ b/linux-user/openrisc/target_signal.h
@@ -26,4 +26,6 @@ typedef struct target_sigaltstack {
 
 #include "../generic/signal.h"
 
+#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1
+
 #endif /* OPENRISC_TARGET_SIGNAL_H */