From 63bf34c7598f3c2a8311841d6b7b5f4f6aa0dca7 Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Fri, 12 May 2017 03:34:33 +0200 Subject: [PATCH 2/5] dump: Acquire BQL around vm_start() in dump thread RH-Author: Fam Zheng Message-id: <20170512033433.1960-1-famz@redhat.com> Patchwork-id: 75073 O-Subject: [RHV-7.4 qemu-kvm-rhev PATCH] dump: Acquire BQL around vm_start() in dump thread Bugzilla: 1445174 RH-Acked-by: Peter Xu RH-Acked-by: Laszlo Ersek RH-Acked-by: Paolo Bonzini This fixes an assertion failure in the following backtrace: __GI___assert_fail memory_region_transaction_commit memory_region_add_eventfd virtio_pci_ioeventfd_assign virtio_bus_set_host_notifier virtio_blk_data_plane_start virtio_bus_start_ioeventfd virtio_vmstate_change vm_state_notify vm_prepare_start vm_start dump_cleanup dump_process dump_thread start_thread clone vm_start need BQL, acquire it if doing cleaning up from main thread. Signed-off-by: Fam Zheng Message-Id: <20170503072819.14462-1-famz@redhat.com> Signed-off-by: Paolo Bonzini (cherry picked from commit 6796b4008bd195e6765a1144dc98a8673e69d169) Upstream made a typo at the end of commit message: s/main thread/detached thread/. Signed-off-by: Fam Zheng Signed-off-by: Miroslav Rezanina --- dump.c | 7 +++++++ include/sysemu/dump.h | 1 + 2 files changed, 8 insertions(+) diff --git a/dump.c b/dump.c index f7b80d8..d9090a2 100644 --- a/dump.c +++ b/dump.c @@ -77,7 +77,13 @@ static int dump_cleanup(DumpState *s) memory_mapping_list_free(&s->list); close(s->fd); if (s->resume) { + if (s->detached) { + qemu_mutex_lock_iothread(); + } vm_start(); + if (s->detached) { + qemu_mutex_unlock_iothread(); + } } return 0; @@ -1804,6 +1810,7 @@ void qmp_dump_guest_memory(bool paging, const char *file, if (detach_p) { /* detached dump */ + s->detached = true; qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread, s, QEMU_THREAD_DETACHED); } else { diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h index ef931be..2672a15 100644 --- a/include/sysemu/dump.h +++ b/include/sysemu/dump.h @@ -157,6 +157,7 @@ typedef struct DumpState { uint32_t sh_info; bool have_section; bool resume; + bool detached; ssize_t note_size; hwaddr memory_offset; int fd; -- 1.8.3.1