From: Tom Lendacky <thomas.lendacky@amd.com>
To: David Woodhouse <dwmw2@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
"x86@kernel.org" <x86@kernel.org>,
"H . Peter Anvin" <hpa@zytor.com>,
Paolo Bonzini <pbonzini@redhat.com>,
"Paul E . McKenney" <paulmck@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"rcu@vger.kernel.org" <rcu@vger.kernel.org>,
"mimoja@mimoja.de" <mimoja@mimoja.de>,
"hewenliang4@huawei.com" <hewenliang4@huawei.com>,
"hushiyuan@huawei.com" <hushiyuan@huawei.com>,
"luolongjun@huawei.com" <luolongjun@huawei.com>,
"hejingxian@huawei.com" <hejingxian@huawei.com>
Subject: Re: [PATCH v3 0/9] Parallel CPU bringup for x86_64
Date: Fri, 17 Dec 2021 11:48:49 -0600 [thread overview]
Message-ID: <1401c5a1-c8a2-cca1-e548-cab143f59d8f@amd.com> (raw)
In-Reply-To: <721484e0fa719e99f9b8f13e67de05033dd7cc86.camel@infradead.org>
On 12/16/21 6:13 PM, David Woodhouse wrote:
> On Thu, 2021-12-16 at 16:52 -0600, Tom Lendacky wrote:
>> On baremetal, I haven't seen an issue. This only seems to have a problem
>> with Qemu/KVM.
>>
>> With 191f08997577 I could boot without issues with and without the
>> no_parallel_bringup. Only after I applied e78fa57dd642 did the failure happen.
>>
>> With e78fa57dd642 I could boot 64 vCPUs pretty consistently, but when I
>> jumped to 128 vCPUs it failed again. When I moved the series to
>> df9726cb7178, then 64 vCPUs also failed pretty consistently.
>>
>> Strange thing is it is random. Sometimes (rarely) it works on the first
>> boot and then sometimes it doesn't, at which point it will reset and
>> reboot 3 or 4 times and then make it past the failure and fully boot.
>
> Hm, some of that is just artifacts of timing, I'm sure. But now I'm
> staring at the way that early_setup_idt() can run in parallel on all
> CPUs, rewriting bringup_idt_descr and loading it.
>
> To start with, let's try unlocking the trampoline_lock much later,
> after cpu_init_exception_handling() has loaded the real IDT.
>
> I think we can probably make secondaries load the real IDT early and
> never use bringup_idt_descr at all, can't we? But let's see if this
> makes it go away, to start with...
>
This still fails. I ran with -d cpu_reset on the command line and will
forward the full log to you. I ran "grep "[ER]IP=" stderr.log | uniq -c"
and got:
128 EIP=00000000 EFL=00000000 [-------] CPL=0 II=0 A20=0 SMM=0 HLT=0
128 EIP=0000fff0 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
These are before running any of the vCPUs.
1 RIP=ffffffff810705c6 RFL=00000206 [-----P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
This is where vCPU0 is at the time of the reset. This address tends to
be different all the time and so I think it is just where it happens to
be when the reset occurs and isn't contributing to the reset.
5 RIP=ffffffff8104aefb RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
1 RIP=ffffffff8104af06 RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
15 RIP=ffffffff8104aefb RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
These are some of the APs and all are in wait_for_master_cpu().
1 EIP=0000101b EFL=00000003 [------C] CPL=0 II=0 A20=1 SMM=0 HLT=0
This seems ok because: CS =9900 00099000 0000ffff 00009b00
So likely in the trampoline code.
1 EIP=0000fff0 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
This one seems odd... could it be the one causing the reset?
CS =f000 ffff0000 0000ffff 00009a00
3 RIP=ffffffff8104aefb RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
2 EIP=0000101b EFL=00000003 [------C] CPL=0 II=0 A20=1 SMM=0 HLT=0
99 EIP=3f36e11b EFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=1
Thanks,
Tom
next prev parent reply other threads:[~2021-12-17 17:48 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-15 14:56 [PATCH v3 0/9] Parallel CPU bringup for x86_64 David Woodhouse
2021-12-15 14:56 ` [PATCH v3 1/9] x86/apic/x2apic: Fix parallel handling of cluster_mask David Woodhouse
2021-12-15 14:56 ` [PATCH v3 2/9] cpu/hotplug: Move idle_thread_get() to <linux/smpboot.h> David Woodhouse
2021-12-15 14:56 ` [PATCH v3 3/9] cpu/hotplug: Add dynamic parallel bringup states before CPUHP_BRINGUP_CPU David Woodhouse
2021-12-15 14:56 ` [PATCH v3 4/9] x86/smpboot: Reference count on smpboot_setup_warm_reset_vector() David Woodhouse
2021-12-15 14:56 ` [PATCH v3 5/9] x86/smpboot: Split up native_cpu_up into separate phases and document them David Woodhouse
2021-12-15 14:56 ` [PATCH v3 6/9] x86/smpboot: Support parallel startup of secondary CPUs David Woodhouse
2021-12-16 14:24 ` Tom Lendacky
2021-12-16 18:24 ` David Woodhouse
2021-12-16 19:00 ` Tom Lendacky
2021-12-16 19:20 ` David Woodhouse
2022-01-29 12:04 ` David Woodhouse
2022-01-31 13:59 ` Borislav Petkov
2022-02-01 10:25 ` David Woodhouse
2022-02-01 10:56 ` Borislav Petkov
2022-02-01 12:39 ` David Woodhouse
2022-02-01 12:56 ` Borislav Petkov
2022-02-01 13:02 ` David Woodhouse
2021-12-15 14:56 ` [PATCH v3 7/9] x86/smpboot: Send INIT/SIPI/SIPI to secondary CPUs in parallel David Woodhouse
2021-12-15 14:56 ` [PATCH v3 8/9] x86/mtrr: Avoid repeated save of MTRRs on boot-time CPU bringup David Woodhouse
2021-12-15 14:56 ` [PATCH v3 9/9] x86/smpboot: Serialize topology updates for secondary bringup David Woodhouse
2021-12-16 16:27 ` [PATCH v3 0/9] Parallel CPU bringup for x86_64 Tom Lendacky
2021-12-16 19:24 ` David Woodhouse
2021-12-16 22:52 ` Tom Lendacky
2021-12-17 0:13 ` David Woodhouse
2021-12-17 10:09 ` Igor Mammedov
2021-12-17 15:40 ` David Woodhouse
2021-12-20 17:10 ` David Woodhouse
2021-12-20 18:54 ` Tom Lendacky
2021-12-20 21:29 ` David Woodhouse
2021-12-20 21:47 ` Tom Lendacky
2021-12-21 22:25 ` Tom Lendacky
2021-12-21 22:33 ` David Woodhouse
2021-12-17 17:48 ` Tom Lendacky [this message]
2021-12-17 19:11 ` David Woodhouse
2021-12-17 19:26 ` David Woodhouse
2021-12-17 20:15 ` Tom Lendacky
2021-12-17 19:46 ` Tom Lendacky
2021-12-17 20:13 ` David Woodhouse
2021-12-17 20:55 ` Tom Lendacky
2021-12-17 22:48 ` David Woodhouse
2022-01-28 9:54 ` David Woodhouse
2022-01-28 21:40 ` Sean Christopherson
2022-01-28 21:48 ` David Woodhouse
2022-01-29 9:22 ` David Woodhouse
2021-12-16 19:52 ` David Woodhouse
2021-12-16 19:55 ` Tom Lendacky
2021-12-16 19:59 ` David Woodhouse
2021-12-27 16:57 ` Paul Menzel
2021-12-28 11:34 ` Paul Menzel
2021-12-28 14:18 ` David Woodhouse
2021-12-29 13:18 ` Paul Menzel
2021-12-29 13:54 ` David Woodhouse
2022-02-14 13:45 ` Paul Menzel
2022-04-21 10:00 ` Mimoja
2022-04-22 21:19 ` Tom Lendacky
2022-06-01 8:30 ` David Woodhouse
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1401c5a1-c8a2-cca1-e548-cab143f59d8f@amd.com \
--to=thomas.lendacky@amd.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=dwmw2@infradead.org \
--cc=hejingxian@huawei.com \
--cc=hewenliang4@huawei.com \
--cc=hpa@zytor.com \
--cc=hushiyuan@huawei.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luolongjun@huawei.com \
--cc=mimoja@mimoja.de \
--cc=mingo@redhat.com \
--cc=paulmck@kernel.org \
--cc=pbonzini@redhat.com \
--cc=rcu@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).