+ kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-fix.patch added to mm-nonmm-unstable branch

+ kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-fix.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: kcov: update documentation on remote coverage collection
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-fix.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Jann Horn <jannh@google.com>
Subject: kcov: update documentation on remote coverage collection
Date: Tue, 19 May 2026 18:06:06 +0200

Adjust the docs on remote coverage collection to reflect the changes made
in "kcov: refactor common handle ID into kcov_common_handle_id" and "kcov:
allow simultaneous KCOV_ENABLE/KCOV_REMOTE_ENABLE".

Link: https://lore.kernel.org/20260519-kcov-docs-v1-1-5bb22f4cb20c@google.com
Signed-off-by: Jann Horn <jannh@google.com>
Suggested-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 Documentation/dev-tools/kcov.rst |    5 +++++
 1 file changed, 5 insertions(+)

--- a/Documentation/dev-tools/kcov.rst~kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-fix
+++ a/Documentation/dev-tools/kcov.rst
@@ -246,6 +246,8 @@ KCOV supports collecting remote coverage
 2. Local kernel background tasks. These are spawned when a userspace process
    interacts with some kernel interface and are usually killed when the process
    exits (e.g. vhost workers).
+   This can be combined with another KCOV instance that is configured for normal
+   coverage collection.
 
 3. Soft interrupts.
 
@@ -262,6 +264,9 @@ gets saved to the ``kcov_handle`` field
 needs to be passed to the newly spawned local tasks via custom kernel code
 modifications. Those tasks should in turn use the passed handle in their
 ``kcov_remote_start`` and ``kcov_remote_stop`` annotations.
+In the kernel, common handles are wrapped in a ``kcov_common_handle_id``, which
+consumes no space in builds without ``CONFIG_KCOV``; subsystems that integrate
+with this mechanism should not need to use any ``#ifdef CONFIG_KCOV`` or such.
 
 KCOV follows a predefined format for both global and common handles. Each
 handle is a ``u64`` integer. Currently, only the one top and the lower 4 bytes
_

Patches currently in -mm which might be from jannh@google.com are

kcov-refactor-common-handle-id-into-kcov_common_handle_id.patch
kcov-allow-simultaneous-kcov_enable-kcov_remote_enable.patch
kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-v2.patch
kcov-allow-simultaneous-kcov_enable-kcov_remote_enable-fix.patch