On Sun, Apr 07, 2019 at 11:23:14AM +0200, Thomas Huth wrote: >QEMU currently crashes when you try to hot-plug an "nvdimm" device >on older machine types: > >$ qemu-system-x86_64 -monitor stdio -M pc-1.1 >QEMU 3.1.92 monitor - type 'help' for more information >(qemu) device_add nvdimm,id=nvdimmn1 >qemu-system-x86_64: /home/thuth/devel/qemu/util/error.c:57: error_setv: > Assertion `*errp == ((void *)0)' failed. >Aborted (core dumped) > >The call to hotplug_handler_pre_plug() in pc_memory_pre_plug() has been >added recently before the check whether nvdimm is enabled. It should >be done after the check. And while we're at it, also check the errp >after the hotplug_handler_pre_plug(), otherwise errors are silently >ignored here.
Thomas, Thanks for pointing this out, while I have some different idea on how to fix this. The reason of the core dump is errp already been set in hotplug_handler_pre_plug(), and this function check acpi hotplug capability. The order of this check is correct, while we should return when errp is set in hotplug_handler_pre_plug(). I got a fix like this, which I have tested and looks good to me. diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 6077d27361..b11f3b15c1 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -2091,6 +2091,9 @@ static void pc_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev, } hotplug_handler_pre_plug(pcms->acpi_dev, dev, errp); + if (*errp) { + return; + } if (is_nvdimm && !ms->nvdimms_state->is_enabled) { error_setg(errp, "nvdimm is not enabled: missing 'nvdimm' in '-M'"); > >Fixes: 9040e6dfa8c3fed87695a3de555d2c775727bb51 >Signed-off-by: Thomas Huth <th...@redhat.com> >--- > hw/i386/pc.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > >diff --git a/hw/i386/pc.c b/hw/i386/pc.c >index 6077d27361..f2c15bf1f2 100644 >--- a/hw/i386/pc.c >+++ b/hw/i386/pc.c >@@ -2078,6 +2078,7 @@ static void pc_memory_pre_plug(HotplugHandler >*hotplug_dev, DeviceState *dev, > const MachineState *ms = MACHINE(hotplug_dev); > const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM); > const uint64_t legacy_align = TARGET_PAGE_SIZE; >+ Error *local_err = NULL; > > /* > * When -no-acpi is used with Q35 machine type, no ACPI is built, >@@ -2090,13 +2091,17 @@ static void pc_memory_pre_plug(HotplugHandler >*hotplug_dev, DeviceState *dev, > return; > } > >- hotplug_handler_pre_plug(pcms->acpi_dev, dev, errp); >- > if (is_nvdimm && !ms->nvdimms_state->is_enabled) { > error_setg(errp, "nvdimm is not enabled: missing 'nvdimm' in '-M'"); > return; > } > >+ hotplug_handler_pre_plug(pcms->acpi_dev, dev, &local_err); >+ if (local_err) { >+ error_propagate(errp, local_err); >+ return; >+ } >+ > pc_dimm_pre_plug(PC_DIMM(dev), MACHINE(hotplug_dev), > pcmc->enforce_aligned_dimm ? NULL : &legacy_align, errp); > } >-- >2.21.0 -- Wei Yang Help you, Help me