Re: [PATCH 5/8] x86: remove dependencies on CONFIG_M... CPU options

Jürgen Groß <[email protected]> Fri, 22 May 2026 21:00:00 +0200

Newsgroups	org.infradead.lists.linux-um,org.kernel.vger.linux-kernel
Message-ID	<[email protected]>

On 22.05.26 20:54, Arnd Bergmann wrote:
> On Fri, May 22, 2026, at 17:46, Juergen Gross wrote:
>> On 22.05.26 16:19, Arnd Bergmann wrote:
>>>
>>> --- a/arch/x86/xen/Kconfig
>>> +++ b/arch/x86/xen/Kconfig
>>> @@ -10,8 +10,7 @@ config XEN
>>>    	select X86_HV_CALLBACK_VECTOR
>>>    	select HIBERNATE_CALLBACKS
>>>    	depends on X86_64 || (X86_32 && X86_PAE)
>>> -	depends on X86_64 || (X86_GENERIC || MPENTIUM4 || MATOM)
>>> -	depends on X86_LOCAL_APIC && X86_TSC
>>> +	depends on X86_LOCAL_APIC
>>
>> This is problematic. See commit 93cd05976498.
>>
>> Maybe use "depends on X86_LOCAL_APIC && X86_L1_CACHE_SHIFT >= 6" instead?
> 
> After patch 6/8, this is always true, so I suppose it would
> if that came first, right?

Yes, agreed.

> 
> On a related note, are there still remaining Xen users on new
> 32-bit guest kernels? I understand that one could still run
> modern kernels on 32-bit Xen-4.2 (EOL in 2015), and that 64-bit
> Xen still supports older 32-bit guest operating systems for
> compatibility, but I'm not sure if there is any reason to
> legitimately run a 32-bit linux-7.x kernel on a 64-bit Xen
> instead of running a better supported 64-bit guest kernel.

 From the logical point of view I totally agree. OTOH users are humans,
so they might not agree with that. ;-)


Juergen

OpenPGP_0xB0DE9DD628BF132F.asc (application/pgp-keys, 3.6 KB)

-----BEGIN PGP PUBLIC KEY BLOCK-----
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=eeAB
-----END PGP PUBLIC KEY BLOCK-----

OpenPGP_signature.asc (application/pgp-signature, 495 B)

-----BEGIN PGP SIGNATURE-----

wsB5BAABCAAjFiEEhRJncuj2BJSl0Jf3sN6d1ii/Ey8FAmoQp7AFAwAAAAAACgkQsN6d1ii/Ey9a
6QgAh5MBUP/4OpwuaOyZwc6fsSJlVytQDOtm/rf1gQY/S3CAsPTsSNh28+h2a7UtqXWlER1tTCyS
sjVY61LeybsoMOiIlkG8eXJUskAPN5GPZxHN2QrIc6ry+1RmfqjYLBeiLQqAUGT1h6VrELQBSGJV
g9pyiPANpbY1+mRlhI4OJIEHkwnEn+7YEQmaUP1B9qsfjJNKvvfpeJgslKGIQEfya34a3o5OAFDd
oseGtkwjVV69i2YN6sXlralYLtlxp2Z3x0GZELPqilU+y/HEAStERbyuAkND30F4pWg1FnXrB667
6I32ZWX0sCsZylu8hGqz/vGhWUAFodyXMBLbUYpniA==
=sWHU
-----END PGP SIGNATURE-----