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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspamd-Queue-Id: 22564140009 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 16b1fjecw7txtf9m51amry7d3t6ennky X-HE-Tag: 1693812713-865856 X-HE-Meta: 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 SVB/ke7m 6hroQ2LfrrrNz2Tf26WkVuv77ZoSBh4wQQn0gfohNXLQGFPae1Sa9YFjjotbGQTESJTuubazVPzVIUgECUzkRUjIU/HWL+g/BgIUed6PCjkjzarel/GzgAv7rx/zmprwZ/pK9IzrSluGKeOmJm0NN6wzxL9ZvKX8cxrKExl0KmLnBNuDZd8lrefmfEXrZgcOicskdOaxaCoUlCDSrjZS9c6hpgPvdYvuJ+r3qSTG2M39mb2MyQ1mKP3+6IoFiEfK/Cem1N4vDQWNPxtyLnDExHC1npmkf72/9uaFGrjTWJYct73uYvYNbM1X4jA== 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 01-09-23 18:29:07, Zhaoyang Huang wrote: > loop alex > > On Thu, Aug 31, 2023 at 8:16 PM Matthew Wilcox wrote: > > > > On Thu, Aug 31, 2023 at 06:52:52PM +0800, zhaoyang.huang wrote: > > > From: Zhaoyang Huang > > > > > > There is no explicit gfp flags to let the allocation skip zero > > > operation when CONFIG_INIT_ON_ALLOC_DEFAULT_ON=y. I would like to make > > > __GFP_SKIP_ZERO be visible even if kasan is not configured. > > > > This bypasses a security feature so you're going to have to do a little > > better than "I want it". > Thanks for pointing this out. What I want to do is to give the user a > way to exempt some types of pages from being zeroed, which could help > on performance issues. Could you be more explicit about those users? Your patch doesn't add any. > Could we have the most safety concern admin > use INIT_ON_FREE while the less concerned use INIT_ON_ALLOC & > __GFP_SKIP_ZERO as a light version method? Are you suggesting the __GFP_SKIP_ZERO would be ignored in any setups except for init_on_alloc? -- Michal Hocko SUSE Labs