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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 2403420014 X-Stat-Signature: wirxtnxmrkties1yc1zhb8bk3itzknn4 X-HE-Tag: 1684483598-946127 X-HE-Meta: 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 TaUNL8ea 7gb5wsCJmXuQpTgczKfUhYSaJTyYSjHdookdLxAg8cMlbbZUWWScxkM4+IcpFjA3f8/c+fC/54/jNX8sbKnAMgoWTLkobr7YPQrzyiRzQVTKkkuHIrW+C8yKqxjpq5+X3OZCeH6buub2ZVZJp36x8a3/Cllb0yTV50wmGyrsX7BKvvp7KP1FpBgyc49tGB8AJ0Wrb3WNp22/BxfuaAbcZGePezKxYBiLozz9Gb5WkP1WfK9wyDBgZCEj2rPfAxcbFXMn4GJvrfXfrdoaQdbZlAaRQ5nGPoib76b9LMfYubBhZ3K0YbKJyUnX7SSyFFWA9PcCsW9MR9xh7smHSDCO4CqfKLLU+RVfkI0WrWUR/SxiV+doqAiLiLc7yQzi8H7lUMBTcbrDwIVdFtU2j7r/Zhu2bGPgSjwxf+nhxm4nnYovy/TN1Ym6IIHCThuc/eNe1K/oOeMfdEUE9mZdclmD9IB7mzw== 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 Fri, May 19, 2023 at 08:40:15AM +0100, David Howells wrote: > Hi Jens, Al, Christoph, > > The first half of this patchset kills off ITER_PIPE to avoid a race between > truncate, iov_iter_revert() on the pipe and an as-yet incomplete DMA to a > bio with unpinned/unref'ed pages from an O_DIRECT splice read. This causes > memory corruption[2]. Instead, we use filemap_splice_read(), which invokes > the buffered file reading code and splices from the pagecache into the > pipe; direct_splice_read(), which bulk-allocates a buffer, reads into it > and then pushes the filled pages into the pipe; or handle it in > filesystem-specific code. If there's a clearly separate first and second half of a 32 patch series, it might really make sense to just split it instead of exceeding every normal attention window..