From 40cd884c85f24c3508e3374d45c577984c5bccbd Mon Sep 17 00:00:00 2001 Message-Id: <40cd884c85f24c3508e3374d45c577984c5bccbd.1342518105.git.minovotn@redhat.com> In-Reply-To: <27a73856ecc481c66c7afac8171f753887f32e31.1342518105.git.minovotn@redhat.com> References: <27a73856ecc481c66c7afac8171f753887f32e31.1342518105.git.minovotn@redhat.com> From: Luiz Capitulino Date: Tue, 5 Jun 2012 14:58:44 +0200 Subject: [PATCH 35/41] qemu-ga: guest-shutdown: become synchronous RH-Author: Luiz Capitulino Message-id: <1338908331-15633-30-git-send-email-lcapitulino@redhat.com> Patchwork-id: 39924 O-Subject: [PATCH RHEL6.4 qemu-kvm 29/36] qemu-ga: guest-shutdown: become synchronous Bugzilla: 827612 RH-Acked-by: Paolo Bonzini RH-Acked-by: Juan Quintela RH-Acked-by: Jeffrey Cody Last commit dropped qemu-ga's SIGCHLD handler, used to automatically reap terminated children processes. This introduced a bug to qmp_guest_shutdown(): it will generate zombies. This problem probably doesn't matter in the success case, as the VM will shutdown anyway, but let's do the right thing and reap the created process. This ultimately means that guest-shutdown is now a synchronous command. An interesting side effect is that guest-shutdown is now able to report an error to the client if shutting down fails. Signed-off-by: Luiz Capitulino Reviewed-by: Eric Blake Signed-off-by: Michael Roth (cherry picked from commit d5dd3498ebf4d6dc8661f6a9a69ae10b50f3a6a6) Signed-off-by: Luiz Capitulino --- qga/commands-posix.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) Signed-off-by: Michal Novotny --- qga/commands-posix.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/qga/commands-posix.c b/qga/commands-posix.c index 434ea99..1cd7cf0 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -41,8 +41,9 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err) { - int ret; const char *shutdown_flag; + int ret, status; + pid_t rpid, pid; slog("guest-shutdown called, mode: %s", mode); if (!has_mode || strcmp(mode, "powerdown") == 0) { @@ -57,8 +58,8 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err) return; } - ret = fork(); - if (ret == 0) { + pid = fork(); + if (pid == 0) { /* child, start the shutdown */ setsid(); fclose(stdin); @@ -71,9 +72,19 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err) slog("guest-shutdown failed: %s", strerror(errno)); } exit(!!ret); - } else if (ret < 0) { - error_set(err, QERR_UNDEFINED_ERROR); + } else if (pid < 0) { + goto exit_err; } + + do { + rpid = waitpid(pid, &status, 0); + } while (rpid == -1 && errno == EINTR); + if (rpid == pid && WIFEXITED(status) && !WEXITSTATUS(status)) { + return; + } + +exit_err: + error_set(err, QERR_UNDEFINED_ERROR); } typedef struct GuestFileHandle { -- 1.7.10.4