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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Chuyi Zhou <zhouchuyi@bytedance.com>
Cc: tglx@kernel.org, mingo@redhat.com, luto@kernel.org,
	peterz@infradead.org, paulmck@kernel.org, muchun.song@linux.dev,
	bp@alien8.de, dave.hansen@linux.intel.com, pbonzini@redhat.com,
	clrkwllms@kernel.org, rostedt@goodmis.org, nadav.amit@gmail.com,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/5] x86/mm: Decouple kernel TLB flushes from
 flush_tlb_info
Message-ID: <20260923105037.4wyE0RLj@linutronix.de>
References: <20260921095359.3784458-1-zhouchuyi@bytedance.com>
 <20260921095359.3784458-5-zhouchuyi@bytedance.com>
 <20260923092819.OVgjJ9Gb@linutronix.de>
 <956efada-ac6a-413c-ac90-324eae428025@bytedance.com>
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In-Reply-To: <956efada-ac6a-413c-ac90-324eae428025@bytedance.com>

On 2026-09-23 18:43:55 [+0800], Chuyi Zhou wrote:
> The ceiling check does not cover all possible inputs, though. For
> example, with start = ULONG_MAX - PAGE_SIZE + 1 and end = TLB_FLUSH_ALL,

Well, due to the number of pages when it is considered to do a full
flush. But "ULONG_MAX - PAGE_SIZE + 1"  isn't a valid start input, is
it?

Sebastian