From 88b94264928e180cad4067a55cb328fe594985b9 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Fri, 26 Jan 2018 18:53:14 +0100 Subject: [PATCH 3/4] savevm: Improve error message for blocked migration RH-Author: Dr. David Alan Gilbert Message-id: <20180126185315.2342-2-dgilbert@redhat.com> Patchwork-id: 78730 O-Subject: [RHEL7.5 qemu-kvm PATCH 1/2] savevm: Improve error message for blocked migration Bugzilla: 1536883 RH-Acked-by: Peter Xu RH-Acked-by: Kevin Wolf RH-Acked-by: Miroslav Rezanina From: Kevin Wolf If an internal snapshot can't be saved because migration is blocked (most commonly probably because of AHCI), we had a really bad error message: $ echo -e "savevm foo\nquit" | qemu -M q35 /tmp/test.qcow2 -monitor stdio QEMU 2.2.50 monitor - type 'help' for more information (qemu) savevm foo Error -22 while writing VM (qemu) quit This patch converts qemu_savevm_state() to the Error infrastructure so that a useful error pointing to the problematic device is produced now: $ echo -e "savevm foo\nquit" | qemu -M q35 /tmp/test.qcow2 -monitor stdio QEMU 2.2.50 monitor - type 'help' for more information (qemu) savevm foo State blocked by non-migratable device '0000:00:1f.2/ich9_ahci' (qemu) quit Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Message-id: 1423574702-23072-1-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi (cherry picked from commit 5d80448c3fc566e505adfa2b566ec8074442c8e1) Signed-off-by: Miroslav Rezanina --- savevm.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/savevm.c b/savevm.c index 731d5c0..d34004e 100644 --- a/savevm.c +++ b/savevm.c @@ -2199,7 +2199,7 @@ void qemu_savevm_state_cancel(void) } } -static int qemu_savevm_state(QEMUFile *f) +static int qemu_savevm_state(QEMUFile *f, Error **errp) { int ret; MigrationParams params = { @@ -2207,7 +2207,7 @@ static int qemu_savevm_state(QEMUFile *f) .shared = 0 }; - if (qemu_savevm_state_blocked(NULL)) { + if (qemu_savevm_state_blocked(errp)) { return -EINVAL; } @@ -2228,6 +2228,7 @@ static int qemu_savevm_state(QEMUFile *f) } if (ret != 0) { qemu_savevm_state_cancel(); + error_setg_errno(errp, -ret, "Error while writing VM state"); } return ret; } @@ -2603,6 +2604,7 @@ void do_savevm(Monitor *mon, const QDict *qdict) qemu_timeval tv; struct tm tm; const char *name = qdict_get_try_str(qdict, "name"); + Error *local_err = NULL; /* Verify if there is a device that doesn't support snapshots and is writable */ bs = NULL; @@ -2661,11 +2663,12 @@ void do_savevm(Monitor *mon, const QDict *qdict) monitor_printf(mon, "Could not open VM state file\n"); goto the_end; } - ret = qemu_savevm_state(f); + ret = qemu_savevm_state(f, &local_err); vm_state_size = qemu_ftell(f); qemu_fclose(f); if (ret < 0) { - monitor_printf(mon, "Error %d while writing VM\n", ret); + monitor_printf(mon, "%s\n", error_get_pretty(local_err)); + error_free(local_err); goto the_end; } -- 1.8.3.1