From c790e4ebfed8174f65d685f5a4f3262873c237a5 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 29 Sep 2021 09:05:46 -0400 Subject: [PATCH] linux-user/ppc: Implement setup_sigtramp Create and record the two signal trampolines. Cc: qemu-ppc@nongnu.org Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-Id: <20210929130553.121567-20-richard.henderson@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/ppc/signal.c | 34 ++++++++++++++++++---------------- linux-user/ppc/target_signal.h | 2 ++ 2 files changed, 20 insertions(+), 16 deletions(-) diff --git a/linux-user/ppc/signal.c b/linux-user/ppc/signal.c index 77f37b9f01..c37744c8fc 100644 --- a/linux-user/ppc/signal.c +++ b/linux-user/ppc/signal.c @@ -203,9 +203,6 @@ struct target_func_ptr { #endif -/* We use the mc_pad field for the signal return trampoline. */ -#define tramp mc_pad - /* See arch/powerpc/kernel/signal.c. */ static target_ulong get_sigframe(struct target_sigaction *ka, CPUPPCState *env, @@ -436,12 +433,7 @@ void setup_frame(int sig, struct target_sigaction *ka, /* Save user regs. */ save_user_regs(env, &frame->mctx); - /* Construct the trampoline code on the stack. */ - encode_trampoline(TARGET_NR_sigreturn, (uint32_t *)&frame->mctx.tramp); - - /* The kernel checks for the presence of a VDSO here. We don't - emulate a vdso, so use a sigreturn system call. */ - env->lr = (target_ulong) h2g(frame->mctx.tramp); + env->lr = default_sigreturn; /* Turn off all fp exceptions. */ env->fpscr = 0; @@ -477,7 +469,6 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, target_sigset_t *set, CPUPPCState *env) { struct target_rt_sigframe *rt_sf; - uint32_t *trampptr = 0; struct target_mcontext *mctx = 0; target_ulong rt_sf_addr, newsp = 0; int i, err = 0; @@ -507,22 +498,17 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, #if defined(TARGET_PPC64) mctx = &rt_sf->uc.tuc_sigcontext.mcontext; - trampptr = &rt_sf->trampoline[0]; sc = &rt_sf->uc.tuc_sigcontext; __put_user(h2g(mctx), &sc->regs); __put_user(sig, &sc->signal); #else mctx = &rt_sf->uc.tuc_mcontext; - trampptr = (uint32_t *)&rt_sf->uc.tuc_mcontext.tramp; #endif save_user_regs(env, mctx); - encode_trampoline(TARGET_NR_rt_sigreturn, trampptr); - /* The kernel checks for the presence of a VDSO here. We don't - emulate a vdso, so use a sigreturn system call. */ - env->lr = (target_ulong) h2g(trampptr); + env->lr = default_rt_sigreturn; /* Turn off all fp exceptions. */ env->fpscr = 0; @@ -720,3 +706,19 @@ abi_long do_swapcontext(CPUArchState *env, abi_ulong uold_ctx, return 0; } + +void setup_sigtramp(abi_ulong sigtramp_page) +{ + uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 * 8, 0); + assert(tramp != NULL); + +#ifdef TARGET_ARCH_HAS_SETUP_FRAME + default_sigreturn = sigtramp_page; + encode_trampoline(TARGET_NR_sigreturn, tramp + 0); +#endif + + default_rt_sigreturn = sigtramp_page + 8; + encode_trampoline(TARGET_NR_rt_sigreturn, tramp + 2); + + unlock_user(tramp, sigtramp_page, 2 * 8); +} diff --git a/linux-user/ppc/target_signal.h b/linux-user/ppc/target_signal.h index 72fcdd9bfa..82184ab8f2 100644 --- a/linux-user/ppc/target_signal.h +++ b/linux-user/ppc/target_signal.h @@ -24,4 +24,6 @@ typedef struct target_sigaltstack { #if !defined(TARGET_PPC64) #define TARGET_ARCH_HAS_SETUP_FRAME #endif +#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1 + #endif /* PPC_TARGET_SIGNAL_H */