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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Action: no action X-Stat-Signature: ezqz7xhnj3xjqkif7zixyng8xun1axf3 X-Rspamd-Queue-Id: D081C140013 X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1782907518-353750 X-HE-Meta: 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 G7/ngyj8 RZzx5GuiMUUUZBMlXE+5Kc2mfsVzlKCoKONiXy9K8vWHuGT3otbg6Wpd3RoCKU1Wo9vw7vxsVtNB+KhbycDjTdKlKMVUC24FSe/cNsFVaDBRzaWGtNdrvYUAkWxKG1564GdsS55klBi6C1rFGmd8Ot8dl0We6+WwO7PFUFMIbk4CXOO1nsN4XbwxECb/jyEkmOMv60gIaHt63wsPy44IefOkh8CuvXAY+ALQP+AIaerz6gWhriBTj4kIZXpv3DNA1zWPVQWTkzx9jMRNRBRyf/ngUWEu95qMay/0NWOCrzKBBXHvG7XqntEai9XR8cBKh3WeFDP7+x3ijvcU= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jun 30, 2026 at 06:48:39PM -0400, Zi Yan wrote: > On Tue Jun 30, 2026 at 3:55 PM EDT, Pedro Falcato wrote: > > On Tue, Jun 30, 2026 at 07:49:12PM +0100, Pedro Falcato wrote: > > snip > >> > >> Other idea: perhaps doing filemap_write_and_wait() after the nr_thps > >> increment in collapse_file() will Just Work and result in a _much_ > >> simpler fix. And it avoids any weird forward-progress issues as no one can > >> write to folios at that point. > >> > > > > Gregg, if you could test this patch, it would be much appreciated. This patch > > (hopefully) makes it so no dirty folio will ever coexist with a ro-THP, thus > > hopefully sidestepping the entire issue in a simple way. Only compile-tested > > and not reviewed. > > I tested the patch on v6.12 kernel with the reproducer from Gregg and > confirmed that the issue is fixed. > > Feel free to add > Tested-by: Zi Yan Awesome, thanks! -- Pedro