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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 30D22C3DA6E for ; Wed, 3 Jan 2024 12:23:51 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rL0HF-0003kL-R6; Wed, 03 Jan 2024 07:23:17 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rL0HD-0003jR-UJ; Wed, 03 Jan 2024 07:23:16 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rL0HB-0006xi-Sv; Wed, 03 Jan 2024 07:23:15 -0500 Received: from pps.filterd (m0353725.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 403Bh6Ps026278; Wed, 3 Jan 2024 12:23:07 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=content-type : message-id : date : mime-version : subject : to : cc : references : from : in-reply-to; s=pp1; bh=s8gB57DJHWAa3S4og3HWARwbbHbA5ER5H6wpJwwXkro=; b=K5DpB1nD9k2CEKjdly8E4TvUUjVT/CqQCVLndLtt+rrURTgtLlMJRiI59WfXJVm9mpnx tNKA+aj1IUpWt/trTYCD/tu9KLVqDlPYuugVRuNnZKTNdA7eSRa0pATHx6jJKfYiyuck vlP2mruXpJERzs4jByvmxhuiQbooW33A2qQB9pQc9l8CLD/d9kjI8HTPmHkSfY5ePB1g Tqd+MnXlkF8QBF5mxU3sTr09fvGoW5BQXwBQssXzj/Cz/Uzw+s+/4bXGBySlSQRiel07 e4wbD3xXNrbKnMUkSLZENSLa6A83UTj7Bzjng7jd+PPBIBGugmb6KCb0ZX4fknE6Zx6N 6w== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3vd6xwsacm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 03 Jan 2024 12:23:06 +0000 Received: from m0353725.ppops.net (m0353725.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 403CN23t018958; Wed, 3 Jan 2024 12:23:06 GMT Received: from ppma13.dal12v.mail.ibm.com (dd.9e.1632.ip4.static.sl-reverse.com [50.22.158.221]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3vd6xwsacc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 03 Jan 2024 12:23:06 +0000 Received: from pps.filterd (ppma13.dal12v.mail.ibm.com [127.0.0.1]) by ppma13.dal12v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 403C3uf1017981; Wed, 3 Jan 2024 12:23:05 GMT Received: from smtprelay04.fra02v.mail.ibm.com ([9.218.2.228]) by ppma13.dal12v.mail.ibm.com (PPS) with ESMTPS id 3vayrkjh4r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 03 Jan 2024 12:23:05 +0000 Received: from smtpav07.fra02v.mail.ibm.com (smtpav07.fra02v.mail.ibm.com [10.20.54.106]) by smtprelay04.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 403CN3T837749310 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 3 Jan 2024 12:23:03 GMT Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B3A5F20043; Wed, 3 Jan 2024 12:23:03 +0000 (GMT) Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2CF8520040; Wed, 3 Jan 2024 12:23:02 +0000 (GMT) Received: from [9.43.62.72] (unknown [9.43.62.72]) by smtpav07.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 3 Jan 2024 12:23:01 +0000 (GMT) Content-Type: multipart/alternative; boundary="------------R806MJOAAw0Sa9p8G8ZxVmlz" Message-ID: Date: Wed, 3 Jan 2024 17:53:01 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 2/2] ppc/spapr: Initialize max_cpus limit to SPAPR_IRQ_NR_IPIS. Content-Language: en-US To: =?UTF-8?Q?C=C3=A9dric_Le_Goater?= , Harsh Prateek Bora , npiggin@gmail.com, qemu-ppc@nongnu.org Cc: danielhb413@gmail.com, david@gibson.dropbear.id.au, qemu-devel@nongnu.org References: <20231123055733.1002890-1-harshpb@linux.ibm.com> <20231123055733.1002890-3-harshpb@linux.ibm.com> From: Kowshik Jois B S In-Reply-To: X-TM-AS-GCONF: 00 X-Proofpoint-GUID: liUXjDAkdQwR0bQFjD7gw5_ju8PZXHMe X-Proofpoint-ORIG-GUID: 0Ib73dWaxJjmeTGnMFnpS8uyhPbyqNTn X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-01-03_06,2024-01-03_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 malwarescore=0 phishscore=0 lowpriorityscore=0 clxscore=1015 priorityscore=1501 impostorscore=0 spamscore=0 mlxlogscore=999 suspectscore=0 adultscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000 definitions=main-2401030102 Received-SPF: none client-ip=148.163.158.5; envelope-from=kowsjois@linux.vnet.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This is a multi-part message in MIME format. --------------R806MJOAAw0Sa9p8G8ZxVmlz Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 23/11/23 14:21, Cédric Le Goater wrote: > On 11/23/23 06:57, Harsh Prateek Bora wrote: >> Initialize the machine specific max_cpus limit as per the maximum range >> of CPU IPIs available. Keeping between 4096 to 8192 will throw IRQ not >> free error due to XIVE/XICS limitation and keeping beyond 8192 will hit >> assert in tcg_region_init or spapr_xive_claim_irq. >> >> Logs: >> >> Without patch fix: >> >> [root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=4097 >> qemu-system-ppc64: IRQ 4096 is not free >> [root@host build]# >> >> On LPAR: >> [root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=8193 >> ** >> ERROR:../tcg/region.c:774:tcg_region_init: assertion failed: >> (region_size >= 2 * page_size) >> Bail out! ERROR:../tcg/region.c:774:tcg_region_init: assertion failed: >> (region_size >= 2 * page_size) >> Aborted (core dumped) >> [root@host build]# >> >> On x86: >> [root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=8193 >> qemu-system-ppc64: ../hw/intc/spapr_xive.c:596: spapr_xive_claim_irq: >> Assertion `lisn < xive->nr_irqs' failed. >> Aborted (core dumped) >> [root@host build]# >> >> With patch fix: >> [root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=4097 >> qemu-system-ppc64: Invalid SMP CPUs 4097. The max CPUs supported by >> machine 'pseries-8.2' is 4096 >> [root@host build]# >> >> Signed-off-by: Harsh Prateek Bora > > > Reviewed-by: Cédric Le Goater > > Thanks, > > C. > > > >> --- >>   hw/ppc/spapr.c | 9 +++------ >>   1 file changed, 3 insertions(+), 6 deletions(-) >> >> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c >> index df09aa9d6a..222d926f46 100644 >> --- a/hw/ppc/spapr.c >> +++ b/hw/ppc/spapr.c >> @@ -4647,13 +4647,10 @@ static void >> spapr_machine_class_init(ObjectClass *oc, void *data) >>       mc->block_default_type = IF_SCSI; >>         /* >> -     * Setting max_cpus to INT32_MAX. Both KVM and TCG max_cpus values >> -     * should be limited by the host capability instead of hardcoded. >> -     * max_cpus for KVM guests will be checked in kvm_init(), and TCG >> -     * guests are welcome to have as many CPUs as the host are capable >> -     * of emulate. >> +     * While KVM determines max cpus in kvm_init() using >> kvm_max_vcpus(), >> +     * In TCG the limit is restricted by the range of CPU IPIs >> available. >>        */ >> -    mc->max_cpus = INT32_MAX; >> +    mc->max_cpus = SPAPR_IRQ_NR_IPIS; >>         mc->no_parallel = 1; >>       mc->default_boot_order = ""; > > I've applied these patches and verified on the latest upstream qemu. > The code is working as expected. Tested-by: Kowshik > Jois --------------R806MJOAAw0Sa9p8G8ZxVmlz Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit


On 23/11/23 14:21, Cédric Le Goater wrote:
On 11/23/23 06:57, Harsh Prateek Bora wrote:
Initialize the machine specific max_cpus limit as per the maximum range
of CPU IPIs available. Keeping between 4096 to 8192 will throw IRQ not
free error due to XIVE/XICS limitation and keeping beyond 8192 will hit
assert in tcg_region_init or spapr_xive_claim_irq.

Logs:

Without patch fix:

[root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=4097
qemu-system-ppc64: IRQ 4096 is not free
[root@host build]#

On LPAR:
[root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=8193
**
ERROR:../tcg/region.c:774:tcg_region_init: assertion failed:
(region_size >= 2 * page_size)
Bail out! ERROR:../tcg/region.c:774:tcg_region_init: assertion failed:
(region_size >= 2 * page_size)
Aborted (core dumped)
[root@host build]#

On x86:
[root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=8193
qemu-system-ppc64: ../hw/intc/spapr_xive.c:596: spapr_xive_claim_irq:
Assertion `lisn < xive->nr_irqs' failed.
Aborted (core dumped)
[root@host build]#

With patch fix:
[root@host build]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=4097
qemu-system-ppc64: Invalid SMP CPUs 4097. The max CPUs supported by
machine 'pseries-8.2' is 4096
[root@host build]#

Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>


Reviewed-by: Cédric Le Goater <clg@kaod.org>

Thanks,

C.



---
  hw/ppc/spapr.c | 9 +++------
  1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index df09aa9d6a..222d926f46 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -4647,13 +4647,10 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
      mc->block_default_type = IF_SCSI;
        /*
-     * Setting max_cpus to INT32_MAX. Both KVM and TCG max_cpus values
-     * should be limited by the host capability instead of hardcoded.
-     * max_cpus for KVM guests will be checked in kvm_init(), and TCG
-     * guests are welcome to have as many CPUs as the host are capable
-     * of emulate.
+     * While KVM determines max cpus in kvm_init() using kvm_max_vcpus(),
+     * In TCG the limit is restricted by the range of CPU IPIs available.
       */
-    mc->max_cpus = INT32_MAX;
+    mc->max_cpus = SPAPR_IRQ_NR_IPIS;
        mc->no_parallel = 1;
      mc->default_boot_order = ""; 

I've applied these patches and verified on the latest upstream qemu. The code is working as expected.

Tested-by: Kowshik Jois<kowsjois@linux.ibm.com>
--------------R806MJOAAw0Sa9p8G8ZxVmlz--