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Message-ID: <5694b2bd-de40-45c0-8b38-ac01bc11798a@zytor.com>
Date:   Thu, 12 Oct 2023 14:21:39 -0700
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Subject: Re: [PATCH v2 0/4] Introduce %rip-relative addressing to PER_CPU_VAR
 macro
Content-Language: en-US
To:     Uros Bizjak <ubizjak@gmail.com>
Cc:     Dave Hansen <dave.hansen@intel.com>, x86@kernel.org,
        xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org,
        Juergen Gross <jgross@suse.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>
References: <20231012201743.292149-1-ubizjak@gmail.com>
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From:   "H. Peter Anvin" <hpa@zytor.com>
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On 10/12/23 14:17, Uros Bizjak wrote:
>>
>> Are you PIC-adjusting the percpu variables as well?
> 
> After this patch (and after fixing percpu_stable_op to use "a" operand
> modifier on GCC), the only *one* remaining absolute reference to
> percpu variable remain in xen-head.S, where:
> 
>      movq    $INIT_PER_CPU_VAR(fixed_percpu_data),%rax
> 
> should be changed to use leaq.
> 
> All others should then be (%rip)-relative.
> 

I mean, the symbols themselves are relative, not absolute?

	-hpa