From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:36975) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hDVrN-0004aO-CI for qemu-devel@nongnu.org; Mon, 08 Apr 2019 11:06:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hDVrM-0006vF-8X for qemu-devel@nongnu.org; Mon, 08 Apr 2019 11:06:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48762) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hDVrL-0006uJ-T1 for qemu-devel@nongnu.org; Mon, 08 Apr 2019 11:06:56 -0400 References: <20190407092314.11066-1-thuth@redhat.com> <20190408134517.GA9047@richard> From: Thomas Huth Message-ID: <14147807-8723-adac-dffb-31b7bbd0fc3b@redhat.com> Date: Mon, 8 Apr 2019 17:06:49 +0200 MIME-Version: 1.0 In-Reply-To: <20190408134517.GA9047@richard> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH for-4.0] hw/i386/pc: Fix crash when hot-plugging nvdimm on older machine types List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wei Yang Cc: Xiao Guangrong , "Michael S. Tsirkin" , qemu-devel@nongnu.org, Paolo Bonzini , Eduardo Habkost On 08/04/2019 15.45, Wei Yang wrote: > 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; > + } Not sure, but I think you can not rely on the fact that the caller set *errp = NULL already... that's why it is more common to use a local_err variable and error_propagate() for such cases (which is what I did in my patch). Also, why don't you want the "nvdimm is not enabled: missing 'nvdimm' in '-M'" check to be done first? Thomas > 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 >> --- >> 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 > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 18786C10F13 for ; Mon, 8 Apr 2019 15:08:26 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CCD0721473 for ; Mon, 8 Apr 2019 15:08:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CCD0721473 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; 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Mon, 8 Apr 2019 15:06:54 +0000 (UTC) Received: from thuth.remote.csb (ovpn-116-50.ams2.redhat.com [10.36.116.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id A18FD60472; Mon, 8 Apr 2019 15:06:50 +0000 (UTC) To: Wei Yang References: <20190407092314.11066-1-thuth@redhat.com> <20190408134517.GA9047@richard> From: Thomas Huth Openpgp: preference=signencrypt Autocrypt: addr=thuth@redhat.com; keydata= xsFNBFH7eUwBEACzyOXKU+5Pcs6wNpKzrlJwzRl3VGZt95VCdb+FgoU9g11m7FWcOafrVRwU yYkTm9+7zBUc0sW5AuPGR/dp3pSLX/yFWsA/UB4nJsHqgDvDU7BImSeiTrnpMOTXb7Arw2a2 4CflIyFqjCpfDM4MuTmzTjXq4Uov1giGE9X6viNo1pxyEpd7PanlKNnf4PqEQp06X4IgUacW tSGj6Gcns1bCuHV8OPWLkf4hkRnu8hdL6i60Yxz4E6TqlrpxsfYwLXgEeswPHOA6Mn4Cso9O 0lewVYfFfsmokfAVMKWzOl1Sr0KGI5T9CpmRfAiSHpthhHWnECcJFwl72NTi6kUcUzG4se81 O6n9d/kTj7pzTmBdfwuOZ0YUSqcqs0W+l1NcASSYZQaDoD3/SLk+nqVeCBB4OnYOGhgmIHNW 0CwMRO/GK+20alxzk//V9GmIM2ACElbfF8+Uug3pqiHkVnKqM7W9/S1NH2qmxB6zMiJUHlTH gnVeZX0dgH27mzstcF786uPcdEqS0KJuxh2kk5IvUSL3Qn3ZgmgdxBMyCPciD/1cb7/Ahazr 3ThHQXSHXkH/aDXdfLsKVuwDzHLVSkdSnZdt5HHh75/NFHxwaTlydgfHmFFwodK8y/TjyiGZ zg2Kje38xnz8zKn9iesFBCcONXS7txENTzX0z80WKBhK+XSFJwARAQABzRxUaG9tYXMgSHV0 aCA8dGguaHV0aEBnbXguZGU+wsF7BBMBAgAlAhsDBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIX gAUCUfuWKwIZAQAKCRAu2dd0/nAttbe/EACb9hafyOb2FmhUqeAiBORSsUifFacQ7laVjcgR I4um8CSHvxijYftpkM2EdAtmXIKgbNDpQoXcWLXB9lu9mLgTO4DVT00TRR65ikn3FCWcyT74 ENTOzRKyKLsDCjhXKPblTPIQbYAUCOWElcyAPm0ERd62fA/rKNxgIiNo/l4UODOMoOJm2/Ox ZoTckW68Eqv7k9L7m7j+Hn3hoDTjAmcCBJt+j7pOhzWvCbqoNOIH8C8qvPaNlrba+R/K6jkO 6jZkTbYQpGIofEQJ/TNn38IsNGpI1ALTHWFtoMxp3j2Imz0REO6dRE2fHRN8sVlHgkoeGhmY NbDsDE1jFQOEObFnu0euk//7BXU7tGOHckVAZ8T1smiRPHfQU7UEH2a/grndxJ+PNeM5w7n2 l+FN3cf2KgPotCK2s9MjSdZA7C5e3rFYO8lqiqTJKvc62vqp3e7B0Kjyy5/QtzSOejBij2QL xkKSFNtxIz4MtuxN8e3IDQNxsKry3nF7R4MDvouXlMo6wP9KuyNWb+vFJt9GtbgfDMIFVamp ZfhEWzWRJH4VgksENA4K/BzjEHCcbTUb1TFsiB1VRnBPJ0SqlvifnfKk6HcpkDk6Pg8Q5FOJ gbNHrdgXsm+m/9GF2zUUr+rOlhVbK23TUqKqPfwnD7uxjpakVcJnsVCFqJpZi1F/ga9IN87B TQRR+3lMARAAtp831HniPHb9AuKq3wj83ujZK8lH5RLrfVsB4X1wi47bwo56BqhXpR/zxPTR eOFT0gnbw9UkphVc7uk/alnXMDEmgvnuxv89PwIQX6k3qLABeV7ykJQG/WT5HQ6+2DdGtVw3 2vjYAPiWQeETsgWRRQMDR0/hwp8s8tL/UodwYCScH6Vxx9pdy353L1fK4Bb9G73a+9FPjp9l x+WwKTsltVqSBuSjyZQ3c3EE8qbTidXZxB38JwARH8yN3TX+t65cbBqLl/zRUUUTapHQpUEd yoAsHIml32e4q+3xdLtTdlLi7FgPBItSazcqZPjEcYW73UAuLcmQmfJlQ5PkDiuqcitn+KzH /1pqsTU7QFZjbmSMJyXY0TDErOFuMOjf20b6arcpEqse1V3IKrb+nqqA2azboRm3pEANLAJw iVTwK3qwGRgK5ut6N/Znv20VEHkFUsRAZoOusrIRfR5HFDxlXguAdEz8M/hxXFYYXqOoaCYy 6pJxTjy0Y/tIfmS/g9Bnp8qg9wsrsnk0+XRnDVPak++G3Uq9tJPwpJbyO0vcqEI3vAXkAB7X VXLzvFwi66RrsPUoDkuzj+aCNumtOePDOCpXQGPpKl+l1aYRMN/+lNSk3+1sVuc2C07WnYyE gV/cbEVklPmKrNwu6DeUyD0qI/bVzKMWZAiB1r56hsGeyYcAEQEAAcLBXwQYAQIACQUCUft5 TAIbDAAKCRAu2dd0/nAttYTwEACLAS/THRqXRKb17PQmKwZHerUvZm2klo+lwQ3wNQBHUJAT p2R9ULexyXrJPqjUpy7+voz+FcKiuQBTKyieiIxO46oMxsbXGZ70o3gxjxdYdgimUD6U8PPd JH8tfAL4BR5FZNjspcnscN2jgbF4OrpDeOLyBaj6HPmElNPtECHWCaf1xbIFsZxSDGMA6cUh 0uX3Q8VI7JN1AR2cfiIRY7NrIlWYucJxyKjO3ivWm69nCtsHiJ0wcF8KlVo7F2eLaufo0K8A ynL8SHMF3VEyxsXOP2f1UR9T2Ur30MXcTBpjUxml1TX3RWY5uH89Js/jlIugBwuAmacJ7JYh lTg6sF/GNc4nPb4kk2yktNWTade+TzsllYlJPaorD2Qe8qX0iFUhFC6y9+O6mP4ZvWoYapp9 ezYNuebMgEr93ob1+4sFg3812wNP01WqsGtWCJHnPv/JoonFdMzD/bIkXGEJMk6ks2kxQQZq g6Ik/s/vxOfao/xCn8nHt7GwvVy41795hzK6tbSl+BuyCRp0vfPRP34OnK7+jR2nvQpJu/pU rCELuGwT9hsYkUPjVd4lfylN3mzEc6iAv/wwjsc0DRTSQCpXT3v2ymTAsRKrVaEZLibTXaf+ WslxWek3xNYRiqwwWAJuL652eAlxUgQ5ZS+fXBRTiQpJ+F26I/2lccScRd9G5w== Organization: Red Hat Message-ID: <14147807-8723-adac-dffb-31b7bbd0fc3b@redhat.com> Date: Mon, 8 Apr 2019 17:06:49 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190408134517.GA9047@richard> Content-Type: text/plain; charset="UTF-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 08 Apr 2019 15:06:54 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH for-4.0] hw/i386/pc: Fix crash when hot-plugging nvdimm on older machine types X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, Paolo Bonzini , Xiao Guangrong , Eduardo Habkost , "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Message-ID: <20190408150649._Q_UU7PJMmQNjGBHyEeF8c2K6kasantyHHKngatXp7A@z> On 08/04/2019 15.45, Wei Yang wrote: > 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; > + } Not sure, but I think you can not rely on the fact that the caller set *errp = NULL already... that's why it is more common to use a local_err variable and error_propagate() for such cases (which is what I did in my patch). Also, why don't you want the "nvdimm is not enabled: missing 'nvdimm' in '-M'" check to be done first? Thomas > 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 >> --- >> 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 >