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Shutemov" , =?UTF-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= , Andrei Vagin , Danylo Mocherniuk , Alex Sierra , Alexander Viro , Andrew Morton , Axel Rasmussen , Christian Brauner , Cyrill Gorcunov , Dan Williams , David Hildenbrand , Greg KH , "Gustavo A . R . Silva" , "Liam R . Howlett" , Matthew Wilcox , Mike Rapoport , Nadav Amit , Pasha Tatashin , Peter Xu , Shuah Khan , Suren Baghdasaryan , Vlastimil Babka , Yang Shi , Yun Zhou , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, kernel@collabora.com References: <20230713101415.108875-6-usama.anjum@collabora.com> <7eedf953-7cf6-c342-8fa8-b7626d69ab63@collabora.com> <382f4435-2088-08ce-20e9-bc1a15050861@collabora.com> <44eddc7d-fd68-1595-7e4f-e196abe37311@collabora.com> <1afedab8-5929-61e5-b0da-9c70dc01c254@collabora.com> <94c6b665-bbc2-5030-f9b1-d933791008b8@codeweavers.com> Content-Language: en-GB From: Paul Gofman In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 537524002C X-Stat-Signature: ir99uhoxtqzyiqh3z73c7quz6u9eoeu6 X-Rspam-User: X-HE-Tag: 1690478130-863656 X-HE-Meta: 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 uNydbdod cz2Wvv8u8dJ5PGdINXUSac2oon9x3g3XhKBX0cMs6pySSJYymJMqk+mut4qrvy9AljEW9RxE4jAGTY21X8Qu+JpE6yCFXRQnoBfWQ0AsGWr0O0oxu37XcC4W2xDbs6UNLwIifLFL9RxZb7EX7HU9j+H/q/eyPc9etxV7A3UyWBDdVnds4lacXkTsaS7dK+0zgckAAvVi4Mfeq3dQcP6nfvb2LJ8Xl3QFbo/GA8E1xj80yVMS084P+7gXNLNl4J7Vcku9Kt4BOv/CawSKXiGPgC5NaSA== 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 Windows GetWriteWatch won't work if the range is not withing a single memory view regardless of MEM_LARGE_PAGES (that is, single VirtualAlloc result, somewhat analogous to VMA but not quite), such a call will result in an error. For the context, Windows never auto splits or joins memory views, and basically nothing can be done across views boundary (merging placeholder views is an exception, while unrelated). VirtualProtect (which stands for mprotect) can be done for individual pages withing the view of course, but it is purely per page and doesn't affect view protection flags or result in any splitting of those. VirtualProtect across views adjacent in memory will also fail. On 7/27/23 05:18, Michał Mirosław wrote: > > Is it possible (on Windows) to have MEM_LARGE_PAGES allocation near a > normal one and run GetWriteWatch() on both in one call? If so, how > does it behave / what is expected? > > Best Regards > Michał Mirosław