From: Sohil Mehta <sohil.mehta@intel.com>
To: Shashank Balaji <shashank.mahadasyam@sony.com>,
Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>, <x86@kernel.org>,
"H. Peter Anvin" <hpa@zytor.com>,
Suresh Siddha <suresh.b.siddha@intel.com>,
"K. Y. Srinivasan" <kys@microsoft.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
Long Li <longli@microsoft.com>,
Ajay Kaher <ajay.kaher@broadcom.com>,
Alexey Makhalov <alexey.makhalov@broadcom.com>,
Broadcom internal kernel review list
<bcm-kernel-feedback-list@broadcom.com>,
Jan Kiszka <jan.kiszka@siemens.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Juergen Gross <jgross@suse.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>, <linux-kernel@vger.kernel.org>,
<linux-hyperv@vger.kernel.org>, <virtualization@lists.linux.dev>,
<jailhouse-dev@googlegroups.com>, <kvm@vger.kernel.org>,
<xen-devel@lists.xenproject.org>,
Rahul Bukte <rahul.bukte@sony.com>,
"Daniel Palmer" <daniel.palmer@sony.com>,
Tim Bird <tim.bird@sony.com>, <stable@vger.kernel.org>
Subject: Re: [PATCH 1/3] x86/x2apic: disable x2apic on resume if the kernel expects so
Date: Tue, 3 Feb 2026 13:08:39 -0800 [thread overview]
Message-ID: <0149c37d-7065-4c72-ab56-4cea1a6c15d0@intel.com> (raw)
In-Reply-To: <20260202-x2apic-fix-v1-1-71c8f488a88b@sony.com>
> diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> index d93f87f29d03..cc64d61f82cf 100644
> --- a/arch/x86/kernel/apic/apic.c
> +++ b/arch/x86/kernel/apic/apic.c
> @@ -2456,6 +2456,12 @@ static void lapic_resume(void *data)
> if (x2apic_mode) {
> __x2apic_enable();
> } else {
> + /*
> + * x2apic may have been re-enabled by the
> + * firmware on resuming from s2ram
> + */
> + __x2apic_disable();
> +
We should likely only disable x2apic on platforms that support it and
need the disabling. How about?
...
} else {
/*
*
*/
if (x2apic_enabled())
__x2apic_disable();
I considered if an error message should be printed along with this. But,
I am not sure if it can really be called a firmware issue. It's probably
just that newer CPUs might have started defaulting to x2apic on.
Can you specify what platform you are encountering this?
next prev parent reply other threads:[~2026-02-03 21:08 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-02 9:51 [PATCH 0/3] x86/x2apic: Fix hang-up of defconfig kernel on resume from s2ram Shashank Balaji
2026-02-02 9:51 ` [PATCH 1/3] x86/x2apic: disable x2apic on resume if the kernel expects so Shashank Balaji
2026-02-02 15:02 ` kernel test robot
2026-02-02 22:31 ` kernel test robot
2026-02-03 0:24 ` Shashank Balaji
2026-02-03 21:08 ` Sohil Mehta [this message]
2026-02-04 9:17 ` Shashank Balaji
2026-02-04 18:53 ` Sohil Mehta
2026-02-05 6:07 ` Shashank Balaji
2026-02-05 23:18 ` Sohil Mehta
2026-02-06 3:44 ` Shashank Balaji
2026-02-06 8:57 ` Shashank Balaji
2026-02-07 0:37 ` Sohil Mehta
2026-02-02 9:51 ` [PATCH 2/3] x86/defconfig: add CONFIG_IRQ_REMAP Shashank Balaji
2026-02-02 11:35 ` Andrew Cooper
2026-02-02 11:54 ` Jan Kiszka
2026-02-02 12:12 ` Andrew Cooper
2026-02-02 13:50 ` Jan Kiszka
2026-02-02 9:51 ` [PATCH 3/3] x86/virt: rename x2apic_available to x2apic_without_ir_available Shashank Balaji
2026-02-06 0:10 ` Sohil Mehta
2026-02-06 9:23 ` Shashank Balaji
2026-02-13 7:39 ` Shashank Balaji
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=0149c37d-7065-4c72-ab56-4cea1a6c15d0@intel.com \
--to=sohil.mehta@intel.com \
--cc=ajay.kaher@broadcom.com \
--cc=alexey.makhalov@broadcom.com \
--cc=bcm-kernel-feedback-list@broadcom.com \
--cc=boris.ostrovsky@oracle.com \
--cc=bp@alien8.de \
--cc=daniel.palmer@sony.com \
--cc=dave.hansen@linux.intel.com \
--cc=decui@microsoft.com \
--cc=haiyangz@microsoft.com \
--cc=hpa@zytor.com \
--cc=jailhouse-dev@googlegroups.com \
--cc=jan.kiszka@siemens.com \
--cc=jgross@suse.com \
--cc=kvm@vger.kernel.org \
--cc=kys@microsoft.com \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=longli@microsoft.com \
--cc=mingo@elte.hu \
--cc=mingo@redhat.com \
--cc=pbonzini@redhat.com \
--cc=rahul.bukte@sony.com \
--cc=shashank.mahadasyam@sony.com \
--cc=stable@vger.kernel.org \
--cc=suresh.b.siddha@intel.com \
--cc=tglx@kernel.org \
--cc=tim.bird@sony.com \
--cc=virtualization@lists.linux.dev \
--cc=vkuznets@redhat.com \
--cc=wei.liu@kernel.org \
--cc=x86@kernel.org \
--cc=xen-devel@lists.xenproject.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