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AJvYcCXavjLJng82mLuKR+hRUyKd7Fkaux2uLStKLOkMcjjXMT1qbC39x54OODB9neTIXz7CxmNTWMHpDQ==@kvack.org X-Gm-Message-State: AOJu0Yz7ApWhcCH/KYe/weqdFswKCJGn6sJRaeqYj0nRT7Px+OFMW9G9 6NVPQ5NXSUzjPWSGZVkEJOoQXQib8TDaMSMuyQvDQNMI6HTbN+3/5LjdNicLdB/TySb/L11bDOw E51CQWdrxXVcysQ== X-Google-Smtp-Source: AGHT+IGw6rncY8Zxg7i+a3sTyj/cTgYVjAJmgkG70hNLSfNqxn0MIvjZU+YGtE0bN/lyYtFOJUyzYiuJGMMOBg== X-Received: from wmhf25.prod.google.com ([2002:a7b:cc19:0:b0:46d:ab31:6ece]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:1c95:b0:46e:6af4:ed83 with SMTP id 5b1f17b1804b1-46e6af4efffmr14013925e9.23.1759403121371; Thu, 02 Oct 2025 04:05:21 -0700 (PDT) Date: Thu, 02 Oct 2025 11:05:20 +0000 In-Reply-To: <7dd29a1e-cea8-4889-bff1-462ad00e25fb@intel.com> Mime-Version: 1.0 References: <20250924-b4-asi-page-alloc-v1-0-2d861768041f@google.com> <726d6a45-d732-4c23-a7b7-766d6a62122e@intel.com> <7dd29a1e-cea8-4889-bff1-462ad00e25fb@intel.com> X-Mailer: aerc 0.21.0 Message-ID: Subject: Re: [PATCH 00/21] mm: ASI direct map management From: Brendan Jackman To: Dave Hansen , Yosry Ahmed Cc: Brendan Jackman , Andy Lutomirski , Lorenzo Stoakes , "Liam R. Howlett" , Suren Baghdasaryan , Michal Hocko , Johannes Weiner , Zi Yan , Axel Rasmussen , Yuanchu Xie , Roman Gushchin , , , , , , , , , , , , , , , , Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 24E51C000A X-Stat-Signature: 5ghfar7wtjdg3pu51tpgnahfwyb5gwh7 X-Rspam-User: X-HE-Tag: 1759403122-832787 X-HE-Meta: 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 p51Eq45V tqgiPj2QudA9ioTXASUXNi0u8mExFjyDor1gtIzJNbckRC9SV9wtXFKXIVVpaiQoeDvxPaMAF8/Jc+1J8raWcYD8G3yM5vU7z/5uWyptPEIvyXBYDAehxc16i28aPzJQTMTJkWgFIFU6/EUQcNc7oIuUI5O2hwD9yTsZInJbyTbffGvmvuNb/QoPpQib+eJKqtb8DuosaoVVe1dKcWrsV8X06CArmtdN3Wh5N3S2yfypmZCB+QFr6sWYhhOKRbPRYx3YwIiHz5lYtReLHFK3g5WgNYg== 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: List-Subscribe: List-Unsubscribe: On Wed Oct 1, 2025 at 8:30 PM UTC, Dave Hansen wrote: > On 10/1/25 13:22, Yosry Ahmed wrote: >> On Wed, Oct 01, 2025 at 12:54:42PM -0700, Dave Hansen wrote: >>> On 9/24/25 07:59, Brendan Jackman wrote: >>>> As per [0] I think ASI is ready to start merging. This is the first >>>> step. The scope of this series is: everything needed to set up the >>>> direct map in the restricted address spaces. >>> Brendan! >>> >>> Generally, we ask that patches get review tags before we consider them >>> for being merged. Is there a reason this series doesn't need reviews >>> before it gets merged? >> I think Brendan just meant that this is not an RFC aimed at prompting >> discussion anymore, these are fully functional patches aimed at being >> merged after they are reviewed and iterated on accordingly. > > Just setting expectations ... I think Brendan has probably rewritten > this two or three times. I suggest he's about halfway done; only two or > three rewrites left. ;) Yeah, I'd love to say "... and we have become exceedingly efficient at it" [0], but no, debugging my idiotic freelist and pagetable corruptions was just as hard this time as the first and second times... [0] https://www.youtube.com/watch?v=r51EomcIqA0 > But, seriously, this _is_ a big deal. It's not going to be something > that gets a few tags slapped on it and gets merged. At least that's not > how I expect it to go. Yeah, sorry if this was poorly worded, I'm DEFINITELY not asking anyone to merge this without the requisite acks - "ready for merge" just means "please review this as real grown-up code, I no longer consider this a PoC". And I'm not expecting this to get merged in v2 either :) Maybe worth noting here: there are two broad parties of important reviewers - mm folks and x86 folks. I think we're at risk of a chicken-and-egg problem where party A is thinking "no point in reviewing this too carefully, it's not yet clear that party B is ever gonna accept ASI even in theory". Meanwhile party B says "yeah ASI seems desirable, but I'll keep my nose out until party A has ironed out the details on their side". So, if you can do anything to help develop a consensus on whether we actually want this thing, that would help a lot. Maybe the best way to do that is just to dig into the details anyway, I'm not sure.