All of lore.kernel.org
 help / color / mirror / Atom feed
From: Axel Rasmussen <axelrasmussen@google.com>
To: Alejandro Colomar <alx@kernel.org>, Peter Xu <peterx@redhat.com>
Cc: linux-man@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	Axel Rasmussen <axelrasmussen@google.com>
Subject: [PATCH 01/10] userfaultfd.2: briefly mention two-step feature handshake process
Date: Tue, 19 Sep 2023 12:01:57 -0700	[thread overview]
Message-ID: <20230919190206.388896-2-axelrasmussen@google.com> (raw)
In-Reply-To: <20230919190206.388896-1-axelrasmussen@google.com>

This process is critical for programs which depend on extra features, so
it's worth mentioning here.

Future commits will much more fully describe it in ioctl_userfaultfd.2.

Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
---
 man2/userfaultfd.2 | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/man2/userfaultfd.2 b/man2/userfaultfd.2
index 40354065c..1b2af22f9 100644
--- a/man2/userfaultfd.2
+++ b/man2/userfaultfd.2
@@ -200,8 +200,9 @@ the application must enable it using the
 .B UFFDIO_API
 .BR ioctl (2)
 operation.
-This operation allows a handshake between the kernel and user space
-to determine the API version and supported features.
+This operation allows a two-step handshake between the kernel and user space
+to determine what API version and features the kernel supports,
+and then to enable those features user space wants.
 This operation must be performed before any of the other
 .BR ioctl (2)
 operations described below (or those operations fail with the
-- 
2.42.0.459.ge4e396fd5e-goog


  reply	other threads:[~2023-09-19 19:02 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-19 19:01 [PATCH 00/10] userfaultfd man page updates Axel Rasmussen
2023-09-19 19:01 ` Axel Rasmussen [this message]
2023-09-25 23:26   ` [PATCH 01/10] userfaultfd.2: briefly mention two-step feature handshake process Alejandro Colomar
2023-10-09  8:38   ` Mike Rapoport
2023-09-19 19:01 ` [PATCH 02/10] userfaultfd.2: reword to account for new fault resolution ioctls Axel Rasmussen
2023-09-25 23:29   ` Alejandro Colomar
2023-10-09  8:39   ` Mike Rapoport
2023-09-19 19:01 ` [PATCH 03/10] userfaultfd.2: comment on feature detection in the example program Axel Rasmussen
2023-09-25 23:32   ` Alejandro Colomar
2023-10-09  8:40   ` Mike Rapoport
2023-09-19 19:02 ` [PATCH 04/10] ioctl_userfaultfd.2: fix a few trivial mistakes Axel Rasmussen
2023-09-25 23:37   ` Alejandro Colomar
2023-09-19 19:02 ` [PATCH 05/10] ioctl_userfaultfd.2: describe two-step feature handshake Axel Rasmussen
2023-09-25 23:44   ` Alejandro Colomar
2023-10-09  8:42   ` Mike Rapoport
2023-10-09 10:58     ` Alejandro Colomar
2023-09-19 19:02 ` [PATCH 06/10] ioctl_userfaultfd.2: describe missing UFFDIO_API feature flags Axel Rasmussen
2023-09-25 23:50   ` Alejandro Colomar
2023-10-09  8:45   ` Mike Rapoport
2023-10-09 10:49     ` Alejandro Colomar
2023-09-19 19:02 ` [PATCH 07/10] ioctl_userfaultfd.2: correct and update UFFDIO_API ioctl error codes Axel Rasmussen
2023-09-25 23:52   ` Alejandro Colomar
2023-10-09  8:49     ` Mike Rapoport
2023-10-09 11:01       ` Alejandro Colomar
2023-09-19 19:02 ` [PATCH 08/10] ioctl_userfaultfd.2: clarify the state of the uffdio_api structure on error Axel Rasmussen
2023-09-25 23:56   ` Alejandro Colomar
2023-09-26 17:58     ` Axel Rasmussen
2023-10-09  9:03   ` Mike Rapoport
2023-09-19 19:02 ` [PATCH 09/10] ioctl_userfaultfd.2: fix / update UFFDIO_REGISTER error code list Axel Rasmussen
2023-09-19 19:02 ` [PATCH 10/10] ioctl_userfaultfd.2: document new UFFDIO_POISON ioctl Axel Rasmussen
2023-10-09  9:09   ` Mike Rapoport
2023-10-10 17:13     ` Axel Rasmussen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230919190206.388896-2-axelrasmussen@google.com \
    --to=axelrasmussen@google.com \
    --cc=alx@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-man@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=peterx@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.