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charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20230817-free_pcppages_bulk-v1-0-c14574a9f80c@kernel.org> X-Rspamd-Queue-Id: A2AFB40009 X-Rspam-User: X-Stat-Signature: byywmer83u4xi5xiufmnr3rknk6aamib X-Rspamd-Server: rspam03 X-HE-Tag: 1692613954-873730 X-HE-Meta: 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 54Gc3Mum Tn2SNiXfNmBc1JLnENAFF+zdoXp/mSeI3HO1OdHwSz+UpupDdeCNkcxoDnbAN5O+Aq58QOElD5DCn6VLlnN9fa1r7hIOmyacH+L3fLF75zvwG0oR7WbUmBtNI+suc07LzEkRjOOPvxlUQxB/awuiSynCMTusOHs4TRKfHvZM/SsGFfACmnkG9HTGLGJMKutqhDuztdElaLjBzYEkn4kHC8+L467/B5XaKZMU1qGGHCMbodbeoPZsCy/9gGWkWxAYgccFLGRjYoot+Rb9lllGu9yNo474gErLUxnlY2GNlDrdz9Sg= 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 Thu, Aug 17, 2023 at 11:05:22PM -0700, Chris Li wrote: > In this patch series I want to safeguard > the free_pcppage_bulk against change in the > pcp->count outside of this function. e.g. > by BPF program inject on the function tracepoint. > > I break up the patches into two seperate patches > for the safeguard and clean up. > > Hopefully that is easier to review. > > Signed-off-by: Chris Li This sounds like a maintenance nightmare if internal state can be arbitrary modified by a BPF program and still expected to work properly in all cases. Every review would have to take into account "what if a BPF script modifies state behind our back?" -- Mel Gorman SUSE Labs