Re: Panic starting 6.2.x and later 6.1.x kernels

From: "Limonciello, Mario" <mario.limonciello@amd.com>
To: David R <david@unsolicited.net>, Borislav Petkov <bp@alien8.de>,
	Gabriel David <ultracoolguy@disroot.org>,
	eric.devolder@oracle.com
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Kishon Vijay Abraham I <kvijayab@amd.com>
Subject: Re: Panic starting 6.2.x and later 6.1.x kernels
Date: Wed, 29 Mar 2023 14:17:06 -0500	[thread overview]
Message-ID: <e4a6e5bb-d014-aa55-5eee-65f1c5f59875@amd.com> (raw)
In-Reply-To: <a0ca1e4e-891c-273d-e2d8-eeb9fc4d0c77@unsolicited.net>

On 3/29/2023 14:14, David R wrote:
> On 29/03/2023 20:07, Limonciello, Mario wrote:
>> On 3/29/2023 14:03, David R wrote:
>>>
>>>> Can you guys have a try with this patch to see if it helps the 
>>>> situation?
>>>>
>>>> https://lore.kernel.org/linux-pm/20230329174536.6931-1-mario.limonciello@amd.com/T/#u
>>>>
>>>> Thanks,
>>>
>>> Your patch on top of 6.2.8 brought the crash back I'm afraid.
>>>
>>> Cheers
>>> David
>>
>> Humm.  In that case I'm a bit worried there is some conflicting 
>> patches that caused this result.  Could you try with both
>>
>> e2869bd7af60 and aa06e20f1be6 reverted?  If that also fails, I think a 
>> more complicated bisect removing those commits is needed.
> 
> I note that 6.2.8 still has:
> 
> static bool __init acpi_is_processor_usable(u32 lapic_flags)
> {
>          if (lapic_flags & ACPI_MADT_ENABLED)
>                  return true;
> 
>          if (acpi_support_online_capable && (lapic_flags & 
> ACPI_MADT_ONLINE_CAPABLE))
>                  return true;
> 
>          return false;
> }
> 
> The flag getting set to false won't help unless the patch I tried 
> previously is applied ?
> 
> diff 
> <https://lore.kernel.org/all/20230327191026.3454-2-eric.devolder@oracle.com/#iZ31arch:x86:kernel:acpi:boot.c> --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 1c38174b5f01..7b5b8ed018b0 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -193,7 +193,13 @@ static bool __init acpi_is_processor_usable(u32 lapic_flags)   	if (lapic_flags & ACPI_MADT_ENABLED)
>   		return true;
>   
> - if (acpi_support_online_capable && (lapic_flags & 
> ACPI_MADT_ONLINE_CAPABLE)) + /* + * Prior to MADT.revision 5, the 
> presence of the Local x2/APIC + * structure _implicitly_ noted a 
> possible hotpluggable cpu. + * Starting with MADT.revision 5, the Online 
> Capable bit + * _explicitly_ indicates a hotpluggable cpu. + */ + if 
> (!acpi_support_online_capable || (lapic_flags & ACPI_MADT_ONLINE_CAPABLE))   		return true;
>   
>   	return false;
> -- 
> 

You mean specifically this change:
https://lore.kernel.org/all/20230327191026.3454-2-eric.devolder@oracle.com/

Yes; I suppose that still makes sense.