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[209.85.167.49]) by smtp.gmail.com with ESMTPSA id f25sm13432lfk.291.2021.01.05.11.54.04 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 05 Jan 2021 11:54:05 -0800 (PST) Received: by mail-lf1-f49.google.com with SMTP id m25so1179982lfc.11 for ; Tue, 05 Jan 2021 11:54:04 -0800 (PST) X-Received: by 2002:ac2:4987:: with SMTP id f7mr362618lfl.41.1609876444687; Tue, 05 Jan 2021 11:54:04 -0800 (PST) MIME-Version: 1.0 References: <000000000000886dbd05b7ffa8db@google.com> <20210104124153.0992b1f7fd1a145e193a333f@linux-foundation.org> In-Reply-To: From: Linus Torvalds Date: Tue, 5 Jan 2021 11:53:48 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: kernel BUG at mm/page-writeback.c:LINE! To: Hugh Dickins Cc: Andrew Morton , Matthew Wilcox , syzbot , Linux Kernel Mailing List , Linux-MM , syzkaller-bugs Content-Type: text/plain; charset="UTF-8" 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, Jan 5, 2021 at 11:31 AM Linus Torvalds wrote: > > On Mon, Jan 4, 2021 at 7:29 PM Hugh Dickins wrote: > > > > > So the one-liner of changing the "if" to "while" in > > > wait_on_page_writeback() should get us back to what we used to do. > > > > I think that is the realistic way to go. > > Yeah, that's what I'll do. I took your "way to go" statement as an ack, and made it all be commit c2407cf7d22d ("mm: make wait_on_page_writeback() wait for multiple pending writebacks"). Linus