summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAndrey Konovalov <andreyknvl@google.com>2021-04-30 09:00:24 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-04-30 21:20:42 +0300
commitf359074768bf406b64d62560e88ff9820b600220 (patch)
treef285634018440a1a8f2cabdcddab905f02cb3c0b
parent836f79a2660533c8302f1154168018d9d76458af (diff)
downloadlinux-f359074768bf406b64d62560e88ff9820b600220.tar.xz
kasan: docs: update boot parameters section
Update the "Boot parameters" section in KASAN documentation: - Mention panic_on_warn. - Mention kasan_multi_shot and its interaction with panic_on_warn. - Clarify kasan.fault=panic interaction with panic_on_warn. - A readability clean-up. Link: https://lkml.kernel.org/r/01364952f15789948f0627d6733b5cdf5209f83a.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--Documentation/dev-tools/kasan.rst14
1 files changed, 10 insertions, 4 deletions
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
index 3020ee3d7a63..37af493c7f8e 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -174,10 +174,16 @@ 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.
+
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
-boot parameters that allow to disable KASAN competely or otherwise control
-particular KASAN features.
+boot parameters that allow disabling KASAN or controlling its features.
- ``kasan=off`` or ``=on`` controls whether KASAN is enabled (default: ``on``).
@@ -194,8 +200,8 @@ particular KASAN features.
traces collection (default: ``on``).
- ``kasan.fault=report`` or ``=panic`` controls whether to only print a KASAN
- report or also panic the kernel (default: ``report``). Note, that tag
- checking gets disabled after the first reported bug.
+ report or also panic the kernel (default: ``report``). The panic happens even
+ if ``kasan_multi_shot`` is enabled.
Implementation details
----------------------