From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49772) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gK3li-0004lH-Ca for qemu-devel@nongnu.org; Tue, 06 Nov 2018 10:59:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gK3ld-0005Gn-4h for qemu-devel@nongnu.org; Tue, 06 Nov 2018 10:59:54 -0500 Date: Tue, 6 Nov 2018 16:58:29 +0100 From: Igor Mammedov Message-ID: <20181106165829.4b9e6e36@redhat.com> In-Reply-To: <1540794581-33578-2-git-send-email-liq3ea@gmail.com> References: <1540794581-33578-1-git-send-email-liq3ea@gmail.com> <1540794581-33578-2-git-send-email-liq3ea@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/2] nvme: don't unref ctrl_mem when device unrealized List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Li Qiang Cc: keith.busch@intel.com, kwolf@redhat.com, mreitz@redhat.com, qemu-devel@nongnu.org, qemu-block@nongnu.org On Sun, 28 Oct 2018 23:29:40 -0700 Li Qiang wrote: > Currently, when hotplug/unhotplug nvme device, it will cause an > assert in object.c. Following is the backtrack: > > ERROR:qom/object.c:981:object_unref: assertion failed: (obj->ref > 0) > > Thread 2 "qemu-system-x86" received signal SIGABRT, Aborted. > [Switching to Thread 0x7fffcbd32700 (LWP 18844)] > 0x00007fffdb9e4fff in raise () from /lib/x86_64-linux-gnu/libc.so.6 > (gdb) bt > /lib/x86_64-linux-gnu/libglib-2.0.so.0 > /lib/x86_64-linux-gnu/libglib-2.0.so.0 > qom/object.c:981 > /home/liqiang02/qemu-upstream/qemu/memory.c:1732 > /home/liqiang02/qemu-upstream/qemu/memory.c:285 > util/qemu-thread-posix.c:504 > /lib/x86_64-linux-gnu/libpthread.so.0 > > This is caused by memory_region_unref in nvme_exit. > > Remove it to make the PCIdevice refcount correct. > > Signed-off-by: Li Qiang nvme device holds a reference to ctrl_mem MemoryRegion as a parent so MemoryRegion will be destroyed later during destruction of nvme object when its cildren are un-parented. Reviewed-by: Igor Mammedov > --- > hw/block/nvme.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/hw/block/nvme.c b/hw/block/nvme.c > index fc7dacb816..359a06d0ad 100644 > --- a/hw/block/nvme.c > +++ b/hw/block/nvme.c > @@ -1331,9 +1331,6 @@ static void nvme_exit(PCIDevice *pci_dev) > g_free(n->namespaces); > g_free(n->cq); > g_free(n->sq); > - if (n->cmbsz) { > - memory_region_unref(&n->ctrl_mem); > - } > > msix_uninit_exclusive_bar(pci_dev); > }