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Date: Thu, 10 Apr 2025 12:51:31 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, Andy Lutomirski <luto@amacapital.net>,
	Dave Hansen <dave@sr71.net>, Brian Gerst <brgerst@gmail.com>,
	Borislav Petkov <bp@alien8.de>, "H . Peter Anvin" <hpa@zytor.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Oleg Nesterov <oleg@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Chang S . Bae" <chang.seok.bae@intel.com>,
	Andy Lutomirski <luto@kernel.org>,
	Fenghua Yu <fenghua.yu@intel.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Uros Bizjak <ubizjak@gmail.com>
Subject: Re: [PATCH 4/8] x86/fpu: Remove the thread::fpu pointer
Message-ID: <Z_eis4nbGK6-SPjP@gmail.com>
References: <20250409211127.3544993-1-mingo@kernel.org>
 <20250409211127.3544993-5-mingo@kernel.org>
 <20250410073948.GT9833@noisy.programming.kicks-ass.net>
 <Z_eZMN4PcOwFnskB@gmail.com>
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* Ingo Molnar <mingo@kernel.org> wrote:

> BTW., Oleg suggested in a previous discussion for us to replace the 
> task->thread.fpu pointer with a build-time calculation - but I'm 
> still not sure it's a good idea.

Actually, I've implemented that already:

  arch/x86/include/asm/processor.h:# define x86_task_fpu(task)    ((struct fpu *)((void *)(task) + sizeof(*(task))))

... then promptly forgot about it. So never mind me. :-)

Thanks,

	Ingo