linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: andrey.konovalov@linux.dev
To: Marco Elver <elver@google.com>, Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	kasan-dev@googlegroups.com,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	Andrey Konovalov <andreyknvl@google.com>
Subject: [PATCH 2/3] kasan: move boot parameters section in documentation
Date: Mon,  9 May 2022 21:07:18 +0200	[thread overview]
Message-ID: <ec9c923f35e7c5312836c4624a7f317dc1ee2c1c.1652123204.git.andreyknvl@google.com> (raw)
In-Reply-To: <5bd58ebebf066593ce0e1d265d60278b5f5a1874.1652123204.git.andreyknvl@google.com>

From: Andrey Konovalov <andreyknvl@google.com>

Move the "Boot parameters" section in KASAN documentation next to the
section that describes KASAN build options.

No content changes.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 Documentation/dev-tools/kasan.rst | 82 +++++++++++++++----------------
 1 file changed, 41 insertions(+), 41 deletions(-)

diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
index aca219ed1198..7f103e975ac2 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -94,6 +94,47 @@ To include alloc and free stack traces of affected slab objects into reports,
 enable ``CONFIG_STACKTRACE``. To include alloc and free stack traces of affected
 physical pages, enable ``CONFIG_PAGE_OWNER`` and boot with ``page_owner=on``.
 
+Boot parameters
+~~~~~~~~~~~~~~~
+
+KASAN is affected by the generic ``panic_on_warn`` command line parameter.
+When it is enabled, KASAN panics the kernel after printing a bug report.
+
+By default, KASAN prints a bug report only for the first invalid memory access.
+With ``kasan_multi_shot``, KASAN prints a report on every invalid access. This
+effectively disables ``panic_on_warn`` for KASAN reports.
+
+Alternatively, independent of ``panic_on_warn``, the ``kasan.fault=`` boot
+parameter can be used to control panic and reporting behaviour:
+
+- ``kasan.fault=report`` or ``=panic`` controls whether to only print a KASAN
+  report or also panic the kernel (default: ``report``). The panic happens even
+  if ``kasan_multi_shot`` is enabled.
+
+Hardware Tag-Based KASAN mode (see the section about various modes below) is
+intended for use in production as a security mitigation. Therefore, it supports
+additional boot parameters that allow disabling KASAN or controlling features:
+
+- ``kasan=off`` or ``=on`` controls whether KASAN is enabled (default: ``on``).
+
+- ``kasan.mode=sync``, ``=async`` or ``=asymm`` controls whether KASAN
+  is configured in synchronous, asynchronous or asymmetric mode of
+  execution (default: ``sync``).
+  Synchronous mode: a bad access is detected immediately when a tag
+  check fault occurs.
+  Asynchronous mode: a bad access detection is delayed. When a tag check
+  fault occurs, the information is stored in hardware (in the TFSR_EL1
+  register for arm64). The kernel periodically checks the hardware and
+  only reports tag faults during these checks.
+  Asymmetric mode: a bad access is detected synchronously on reads and
+  asynchronously on writes.
+
+- ``kasan.vmalloc=off`` or ``=on`` disables or enables tagging of vmalloc
+  allocations (default: ``on``).
+
+- ``kasan.stacktrace=off`` or ``=on`` disables or enables alloc and free stack
+  traces collection (default: ``on``).
+
 Error reports
 ~~~~~~~~~~~~~
 
@@ -208,47 +249,6 @@ traces point to places in code that interacted with the object but that are not
 directly present in the bad access stack trace. Currently, this includes
 call_rcu() and workqueue queuing.
 
-Boot parameters
-~~~~~~~~~~~~~~~
-
-KASAN is affected by the generic ``panic_on_warn`` command line parameter.
-When it is enabled, KASAN panics the kernel after printing a bug report.
-
-By default, KASAN prints a bug report only for the first invalid memory access.
-With ``kasan_multi_shot``, KASAN prints a report on every invalid access. This
-effectively disables ``panic_on_warn`` for KASAN reports.
-
-Alternatively, independent of ``panic_on_warn``, the ``kasan.fault=`` boot
-parameter can be used to control panic and reporting behaviour:
-
-- ``kasan.fault=report`` or ``=panic`` controls whether to only print a KASAN
-  report or also panic the kernel (default: ``report``). The panic happens even
-  if ``kasan_multi_shot`` is enabled.
-
-Hardware Tag-Based KASAN mode (see the section about various modes below) is
-intended for use in production as a security mitigation. Therefore, it supports
-additional boot parameters that allow disabling KASAN or controlling features:
-
-- ``kasan=off`` or ``=on`` controls whether KASAN is enabled (default: ``on``).
-
-- ``kasan.mode=sync``, ``=async`` or ``=asymm`` controls whether KASAN
-  is configured in synchronous, asynchronous or asymmetric mode of
-  execution (default: ``sync``).
-  Synchronous mode: a bad access is detected immediately when a tag
-  check fault occurs.
-  Asynchronous mode: a bad access detection is delayed. When a tag check
-  fault occurs, the information is stored in hardware (in the TFSR_EL1
-  register for arm64). The kernel periodically checks the hardware and
-  only reports tag faults during these checks.
-  Asymmetric mode: a bad access is detected synchronously on reads and
-  asynchronously on writes.
-
-- ``kasan.vmalloc=off`` or ``=on`` disables or enables tagging of vmalloc
-  allocations (default: ``on``).
-
-- ``kasan.stacktrace=off`` or ``=on`` disables or enables alloc and free stack
-  traces collection (default: ``on``).
-
 Implementation details
 ----------------------
 
-- 
2.25.1



  reply	other threads:[~2022-05-09 19:07 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-09 19:07 [PATCH 1/3] kasan: update documentation andrey.konovalov
2022-05-09 19:07 ` andrey.konovalov [this message]
2022-05-10 11:58   ` [PATCH 2/3] kasan: move boot parameters section in documentation Marco Elver
2022-05-09 19:07 ` [PATCH 3/3] kasan: clean-up kconfig options descriptions andrey.konovalov
2022-05-10 11:57   ` Marco Elver
2022-05-10 17:20     ` Andrey Konovalov
2022-05-10 12:05 ` [PATCH 1/3] kasan: update documentation Marco Elver
2022-05-10 17:18   ` Andrey Konovalov

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=ec9c923f35e7c5312836c4624a7f317dc1ee2c1c.1652123204.git.andreyknvl@google.com \
    --to=andrey.konovalov@linux.dev \
    --cc=akpm@linux-foundation.org \
    --cc=andreyknvl@gmail.com \
    --cc=andreyknvl@google.com \
    --cc=dvyukov@google.com \
    --cc=elver@google.com \
    --cc=glider@google.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=ryabinin.a.a@gmail.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox