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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250205122007.GH14028@noisy.programming.kicks-ass.net> X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 59C6C20010 X-Stat-Signature: g8kaootwjmwb5zbechyy11kmr8g9mn7w X-Rspam-User: X-HE-Tag: 1738765034-690578 X-HE-Meta: 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 +gD0MXHp AHmWPYRvuTUPA7pGWDoll1+EaxQNyB5H4WN8dSaEwoppy91SEhUa5xD+gdMOOQfP7X0Dxbvj4SvCuNhsypUKhHAWSn56aNPa/cxI2RX07w1GL40AWPn3uIZNz46CPJ6CSN+KMg3RsFe1F2r3fblqM+kCVye8pzvMNvUlIGHSRnMRb9lw2eHpf/p7z7ADoaZeVjuXrVdd4Cia8sPBAZMNqfDp53WLKwWOt0ZeJJIR/8VBpgeypChdHbjNja8vuGjsWFfji8HJxNxOSRCw= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Feb 05, 2025 at 01:20:07PM +0100, Peter Zijlstra wrote: > On Tue, Feb 04, 2025 at 08:39:52PM -0500, Rik van Riel wrote: > > > diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c > > index 6cf881a942bb..02e1f5c5bca3 100644 > > --- a/arch/x86/mm/tlb.c > > +++ b/arch/x86/mm/tlb.c > > @@ -1000,8 +1000,13 @@ static struct flush_tlb_info *get_flush_tlb_info(struct mm_struct *mm, > > BUG_ON(this_cpu_inc_return(flush_tlb_info_idx) != 1); > > #endif > > > > - info->start = start; > > - info->end = end; > > + /* > > + * Round the start and end addresses to the page size specified > > + * by the stride shift. This ensures partial pages at the end of > > + * a range get fully invalidated. > > + */ > > + info->start = round_down(start, 1 << stride_shift); > > + info->end = round_up(end, 1 << stride_shift); > > info->mm = mm; > > info->stride_shift = stride_shift; > > info->freed_tables = freed_tables; > > Rather than doing this; should we not fix whatever dodgy users are > feeding us non-page-aligned addresses for invalidation? That is, I feel this is worthy of WARN_ONCE at the very least.