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charset="UTF-8" X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: ED4DC180017 X-Stat-Signature: xbxfhsecns5ncbi78cxofy3sb6afjiaf X-Rspam-User: X-HE-Tag: 1684959361-813366 X-HE-Meta: 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 YnD+L6XL UZBqM3Ten71VsRn2xHK1tnpXP8/7a2Hxw1PQdfxcyI7k5NbBrDliNrpTRTCmRKTylFtDrQIaZjscJlQtQknHRWX797WaZ3HNwAG1kS0nSdXMJ7R6lLdcI43qtGNt+J+w/hiTRrPBaao6LLYA6coXbxmjv9C6SUx5Q9qEu7CoNLTAxdUgjHKWpuvgFB4jSecHVwP9eaXWg5+ZYSKLz6LLOl9wlgC2SmaVv3L+FI/XqKUhGygKhZb5csyKua+OwoEf9zjROXYailu9r8t15k+zEPIA9t6Pp3bLTNgHk0HJIWNrDlmkgk5pI/UC74g== 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: Thanks for bringing this to my attention. Regarding io_uring: > > io_uring fundamentally doesn't have the same checks. The kernel side > work can be done from an asynchronous kernel thread. That kernel thread > doesn't have a meaningful PKRU value. The register has a value, but > it's not really related to the userspace threads that are sending it > requests. > I asked the question to the io_uring list [1]. io_uring thread will respect PKRU of the user thread, async or not, the behavior is the same as regular syscall. There will be no issue for io_uring, i.e if it decides to add more memory mapping syscalls to supported cmd in future. [1] https://lore.kernel.org/io-uring/CABi2SkUp45HEt7eQ6a47Z7b3LzW=4m3xAakG35os7puCO2dkng@mail.gmail.com/ Thanks. -Jeff