From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E85CC11F64 for ; Mon, 28 Jun 2021 20:24:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42B9061CD0 for ; Mon, 28 Jun 2021 20:24:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230291AbhF1U0b (ORCPT ); Mon, 28 Jun 2021 16:26:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59450 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234182AbhF1U02 (ORCPT ); Mon, 28 Jun 2021 16:26:28 -0400 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB7DAC061574 for ; Mon, 28 Jun 2021 13:24:00 -0700 (PDT) Received: by mail-ej1-x629.google.com with SMTP id o11so18929024ejd.4 for ; Mon, 28 Jun 2021 13:24:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=umich.edu; s=google-2016-06-03; h=mime-version:from:date:message-id:subject:to; bh=1onvlAo6x1M3c84t9iiFsS/HRyy1SWrHlEXnVWCekPM=; b=TtM0xt0V6jpJuRXz0xpzhwXkPqKXkEwkKTM+dbwgdNPljraw8zqJ98aTPQNWqGJ+2F dESVXOekGksiHbFxbZpcw3gmFq7Sv2QNdtbcBsp4I5vXjIPZ/IIFYF3vA/L772kHpurj brxLJZHrEbZNoB/c+uh6kblyLpuz7zqaQSv8UVIOv9R2z30Ogz/4CqQtLXhlD1B6WSaH zR7qiRmAPPJg8tn3khafW/3d/5vd4N0U4IrSebb7T2ITv2UvSfGd8Iahj8Z42fFFB8fp DFymbzS96VTwQzl8/wEClkYbimZcI0g7vE8Sn4CpF5jIcMxkzkqlMqVLuVZ2DaBK428N 6qCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=1onvlAo6x1M3c84t9iiFsS/HRyy1SWrHlEXnVWCekPM=; b=p04D9S06c49Cb/IbjXzlxfIa6CxQkPjH+GYwcHSL7M0iD72cW5Vwkgd7WcTSONT4hk I7ntASTMocBiuyEzcszDLBmm1cvfJm77+j9CioLEhasvk+cyLOw5RQ+d8DmaYD+dPLyi tylJFwp9M5YdcedLZ+NqCm+t9irTp5HVzzSpqxSkfVhbQhBaIcO3mdPrXn7N+/RbM2MK 1sCAgEVjkkXo63ATgNYjgXh8oYAijjKOmskXDcxtNfoW7NsodXihEteiRWMKXn8xXYrX rodP06Z61UAsZ8xnEuW0kYmH3OIryfsH1xnKWmuJSVqkjiUwXKRqM9zco/fIS3G6Wx0H 6UFA== X-Gm-Message-State: AOAM532IvdNvqXt3Lju3Wfz9s8ftaotv5gEhG3cU2dUY0ZRKD7vKwiZX AxM2gwx4Rl9DMQKjvzaPTgfUzh8otOGdHqVECK1CUynsiyI= X-Google-Smtp-Source: ABdhPJwMJway9ZwJ5gLEaLzFSklWalD7+65keEzvj1WyKSy5sckmm1uIDWN1QMVwmdqPFwin688c+K7Ji9U0KijiJ0U= X-Received: by 2002:a17:906:c006:: with SMTP id e6mr18782423ejz.510.1624911838243; Mon, 28 Jun 2021 13:23:58 -0700 (PDT) MIME-Version: 1.0 From: Olga Kornievskaia Date: Mon, 28 Jun 2021 16:23:47 -0400 Message-ID: Subject: client's caching of server-side capabilities To: linux-nfs Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Hi folks, I have a general question of why the client doesn't throw away the cached server's capabilities on server reboot. Say a client mounted a server when the server didn't support security_labels, then the server was rebooted and support was enabled. Client re-establishes its clientid/session, recovers state, but assumes all the old capabilities apply. A remount is required to clear old/find new capabilities. The opposite is true that a capability could be removed (but I'm assuming that's a less practical example). I'm curious what are the problems of clearing server capabilities and rediscovering them on reboot? Is it because a local filesystem could never have its attributes changed and thus a network file system can't either? Thank you.