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[81.157.153.247]) by smtp.gmail.com with ESMTPSA id h18-20020adfa4d2000000b00241cfa9333fsm32853921wrb.5.2023.01.03.09.50.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Jan 2023 09:50:10 -0800 (PST) Date: Tue, 3 Jan 2023 17:50:09 +0000 From: Lorenzo Stoakes To: Fenghua Yu Cc: Vinod Koul , Dave Jiang , dmaengine@vger.kernel.org, Tony Zhu , Andrew Morton , linux-mm@kvack.org, Christoph Hellwig Subject: Re: [PATCH 09/17] mm: export access_remote_vm() symbol Message-ID: References: <20230103163505.1569356-1-fenghua.yu@intel.com> <20230103163505.1569356-10-fenghua.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Queue-Id: F27994000B X-Rspamd-Server: rspam01 X-Stat-Signature: i6jm1u9ffwrntdwaw3gf7kqw3pkfdbqm X-HE-Tag: 1672768211-70671 X-HE-Meta: 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 jYMG+4Gw 4Fj2y/UpbQj2/LYZA0L0tt+z0C+e/1IRdJ773M17g3yGWapk1g61dh2VzPtiy6B0U4fLfzBm43ZQGdH5IIyMv/92tyhAA0CtX8L+ys903JkaJrkOHJ2Fmus0pnZUvqe0UV8XK 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 03, 2023 at 05:45:30PM +0000, Lorenzo Stoakes wrote: > Can you explain what use case you have for exporting this? Currently this is > only used by procfs. > Ugh I hit send too soon ! I see you've explained the _why_ (i.e. idxd). The other two points remain, however. > Additionally, it relies on a reference count being held on the mm which seems a > little risky exposing to a driver. > > Is there a reason you can't use access_process_vm() which is exported and > additionally handles the refrencing?