From 80b92bfe3bb75aa6688f58af9df356757a46f659 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Mon, 5 Sep 2022 23:05:47 +0200 Subject: kasan: dynamically allocate stack ring entries Instead of using a large static array, allocate the stack ring dynamically via memblock_alloc(). The size of the stack ring is controlled by a new kasan.stack_ring_size command-line parameter. When kasan.stack_ring_size is not provided, the default value of 32 << 10 is used. When the stack trace collection is disabled via kasan.stacktrace=off, the stack ring is not allocated. Link: https://lkml.kernel.org/r/03b82ab60db53427e9818e0b0c1971baa10c3cbc.1662411800.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Acked-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Peter Collingbourne Signed-off-by: Andrew Morton --- Documentation/dev-tools/kasan.rst | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation/dev-tools') diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index 7bd38c181018..5c93ab915049 100644 --- a/Documentation/dev-tools/kasan.rst +++ b/Documentation/dev-tools/kasan.rst @@ -112,10 +112,12 @@ parameter can be used to control panic and reporting behaviour: if ``kasan_multi_shot`` is enabled. Software and Hardware Tag-Based KASAN modes (see the section about various -modes below) support disabling stack trace collection: +modes below) support altering stack trace collection behavior: - ``kasan.stacktrace=off`` or ``=on`` disables or enables alloc and free stack traces collection (default: ``on``). +- ``kasan.stack_ring_size=`` specifies the number of entries + in the stack ring (default: ``32768``). Hardware Tag-Based KASAN mode is intended for use in production as a security mitigation. Therefore, it supports additional boot parameters that allow -- cgit v1.2.3