linux-kernel - Re: [RFC PATCH v7 17/37] x86/apic: Unionize apic regs for 32bit/64bit access w/o type casting

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Message-ID: <62c17e68-8078-42da-a616-75cd0885001d@amd.com>
Date: Wed, 25 Jun 2025 06:45:46 +0530
From: Neeraj Upadhyay <Neeraj.Upadhyay@....com>
To: "Huang, Kai" <kai.huang@...el.com>,
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Subject: Re: [RFC PATCH v7 17/37] x86/apic: Unionize apic regs for 32bit/64bit
 access w/o type casting



On 6/24/2025 3:58 PM, Huang, Kai wrote:
> 
>> +struct apic_page {
>> +	union {
>> +		u64     regs64[PAGE_SIZE / 8];
>> +		u32     regs[PAGE_SIZE / 4];
>> +		u8      bytes[PAGE_SIZE];
>> +	};
>> +} __aligned(PAGE_SIZE);
> 
> The 'bytes' field is never used.  Should it be removed?
> 

It's used in patch 25/37, in get_reg_bitmap(). I will describe
it in the commit log of this patch. Thanks for the review!


- Neeraj