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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230104002732.232573-1-mike.kravetz@oracle.com> X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 4D2B01C0008 X-Stat-Signature: src69rsjdayr8zmxecpo66mydexkpjtw X-HE-Tag: 1672818384-700134 X-HE-Meta: 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 cVm3GIJY QDFAuL7UNBAluGRk= 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: On Tue 03-01-23 16:27:32, Mike Kravetz wrote: > zap_page_range was originally designed to unmap pages within an address > range that could span multiple vmas. While working on [1], it was > discovered that all callers of zap_page_range pass a range entirely within > a single vma. In addition, the mmu notification call within zap_page > range does not correctly handle ranges that span multiple vmas. When > crossing a vma boundary, a new mmu_notifier_range_init/end call pair > with the new vma should be made. > > Instead of fixing zap_page_range, do the following: > - Create a new routine zap_vma_pages() that will remove all pages within > the passed vma. Most users of zap_page_range pass the entire vma and > can use this new routine. > - For callers of zap_page_range not passing the entire vma, instead call > zap_page_range_single(). > - Remove zap_page_range. > > [1] https://lore.kernel.org/linux-mm/20221114235507.294320-2-mike.kravetz@oracle.com/ > Suggested-by: Peter Xu > Signed-off-by: Mike Kravetz This looks even better than the previous version. Acked-by: Michal Hocko minor nit [...] > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index ad608ef2a243..ffa36cfe5884 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -2713,7 +2713,7 @@ void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb) > * > * The caller must hold lock_page_memcg(). Most callers have the folio > * locked. A few have the folio blocked from truncation through other > - * means (eg zap_page_range() has it mapped and is holding the page table > + * means (eg zap_vma_pages() has it mapped and is holding the page table > * lock). This can also be called from mark_buffer_dirty(), which I > * cannot prove is always protected against truncate. strictly speaking this should be unmap_page_range -- Michal Hocko SUSE Labs