From a9175169cc55ecff23a158dfee7d9cbb0b75d185 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 12 May 2016 18:47:42 +0100 Subject: [PATCH] linux-user: Support for restarting system calls for tilegx targets Update the tilegx main loop and sigreturn code: * on TARGET_ERESTARTSYS, wind guest PC backwards to repeat syscall insn * return -TARGET_QEMU_ESIGRETURN from sigreturn rather than current R_RE * handle TARGET_QEMU_ESIGRETURN in the main loop as the indication that the main loop should not touch any guest CPU state Note that this fixes a bug where a sigreturn which happened to have an errno value in TILEGX_R_RE would incorrectly cause TILEGX_R_ERR to get set. Signed-off-by: Peter Maydell Signed-off-by: Riku Voipio --- linux-user/main.c | 21 +++++++++++++-------- linux-user/signal.c | 2 +- linux-user/tilegx/target_signal.h | 1 + 3 files changed, 15 insertions(+), 9 deletions(-) diff --git a/linux-user/main.c b/linux-user/main.c index a532221ebc..4607e48278 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -3706,15 +3706,20 @@ void cpu_loop(CPUTLGState *env) cpu_exec_end(cs); switch (trapnr) { case TILEGX_EXCP_SYSCALL: - env->regs[TILEGX_R_RE] = do_syscall(env, env->regs[TILEGX_R_NR], - env->regs[0], env->regs[1], - env->regs[2], env->regs[3], - env->regs[4], env->regs[5], - env->regs[6], env->regs[7]); - env->regs[TILEGX_R_ERR] = TILEGX_IS_ERRNO(env->regs[TILEGX_R_RE]) - ? - env->regs[TILEGX_R_RE] - : 0; + { + abi_ulong ret = do_syscall(env, env->regs[TILEGX_R_NR], + env->regs[0], env->regs[1], + env->regs[2], env->regs[3], + env->regs[4], env->regs[5], + env->regs[6], env->regs[7]); + if (ret == -TARGET_ERESTARTSYS) { + env->pc -= 8; + } else if (ret != -TARGET_QEMU_ESIGRETURN) { + env->regs[TILEGX_R_RE] = ret; + env->regs[TILEGX_R_ERR] = TILEGX_IS_ERRNO(ret) ? -ret : 0; + } break; + } case TILEGX_EXCP_OPCODE_EXCH: do_exch(env, true, false); break; diff --git a/linux-user/signal.c b/linux-user/signal.c index 71a8e2ac66..b4641dffb8 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -5709,7 +5709,7 @@ long do_rt_sigreturn(CPUTLGState *env) } unlock_user_struct(frame, frame_addr, 0); - return env->regs[TILEGX_R_RE]; + return -TARGET_QEMU_ESIGRETURN; badframe: diff --git a/linux-user/tilegx/target_signal.h b/linux-user/tilegx/target_signal.h index b595f985cf..fcf10405c4 100644 --- a/linux-user/tilegx/target_signal.h +++ b/linux-user/tilegx/target_signal.h @@ -25,4 +25,5 @@ static inline abi_ulong get_sp_from_cpustate(CPUTLGState *state) return state->regs[TILEGX_R_SP]; } + #endif /* TARGET_SIGNAL_H */