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| author | Timothy E Baldwin <T.E.Baldwin99@members.leeds.ac.uk> | 2016-05-12 18:47:30 +0100 |
|---|---|---|
| committer | Riku Voipio <riku.voipio@linaro.org> | 2016-05-27 14:49:49 +0300 |
| commit | 0284b03ba3f47da53b6b46293a3d586c08829f7e (patch) | |
| tree | a7942bf22838565bf88cfccf69af317c36d90725 /linux-user/main.c | |
| parent | 499b5d176a77773cab5479264a3d5067176df21c (diff) | |
| download | qemu-0284b03ba3f47da53b6b46293a3d586c08829f7e.tar.gz | |
linux-user: Support for restarting system calls for x86 targets
Update the x86 main loop and sigreturn code:
* on TARGET_ERESTARTSYS, wind guest PC backwards to repeat syscall insn
* set all guest CPU state within signal.c code rather than passing it
back out as the "return code" from do_sigreturn()
* handle TARGET_QEMU_ESIGRETURN in the main loop as the indication
that the main loop should not touch EAX
Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-5-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: Commit message tweaks; drop TARGET_USE_ERESTARTSYS define]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Diffstat (limited to 'linux-user/main.c')
| -rw-r--r-- | linux-user/main.c | 47 |
1 files changed, 29 insertions, 18 deletions
diff --git a/linux-user/main.c b/linux-user/main.c index 95ed11d85c..da5a0333b6 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -285,6 +285,7 @@ void cpu_loop(CPUX86State *env) CPUState *cs = CPU(x86_env_get_cpu(env)); int trapnr; abi_ulong pc; + abi_ulong ret; target_siginfo_t info; for(;;) { @@ -294,28 +295,38 @@ void cpu_loop(CPUX86State *env) switch(trapnr) { case 0x80: /* linux syscall from int $0x80 */ - env->regs[R_EAX] = do_syscall(env, - env->regs[R_EAX], - env->regs[R_EBX], - env->regs[R_ECX], - env->regs[R_EDX], - env->regs[R_ESI], - env->regs[R_EDI], - env->regs[R_EBP], - 0, 0); + ret = do_syscall(env, + env->regs[R_EAX], + env->regs[R_EBX], + env->regs[R_ECX], + env->regs[R_EDX], + env->regs[R_ESI], + env->regs[R_EDI], + env->regs[R_EBP], + 0, 0); + if (ret == -TARGET_ERESTARTSYS) { + env->eip -= 2; + } else if (ret != -TARGET_QEMU_ESIGRETURN) { + env->regs[R_EAX] = ret; + } break; #ifndef TARGET_ABI32 case EXCP_SYSCALL: /* linux syscall from syscall instruction */ - env->regs[R_EAX] = do_syscall(env, - env->regs[R_EAX], - env->regs[R_EDI], - env->regs[R_ESI], - env->regs[R_EDX], - env->regs[10], - env->regs[8], - env->regs[9], - 0, 0); + ret = do_syscall(env, + env->regs[R_EAX], + env->regs[R_EDI], + env->regs[R_ESI], + env->regs[R_EDX], + env->regs[10], + env->regs[8], + env->regs[9], + 0, 0); + if (ret == -TARGET_ERESTARTSYS) { + env->eip -= 2; + } else if (ret != -TARGET_QEMU_ESIGRETURN) { + env->regs[R_EAX] = ret; + } break; #endif case EXCP0B_NOSEG: |