diff options
| author | Aleksandr Nogikh <nogikh@google.com> | 2020-10-29 17:36:18 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-11-02 18:00:20 -0800 |
| commit | b08e84da205023009c456bd7f33feb83c5191c60 (patch) | |
| tree | ae9485a2eee965fbe97dba350887c00cb71e7c9e | |
| parent | 0e8c266c59b56acc94d3289d3b3fb142d22fb46c (diff) | |
kernel: make kcov_common_handle consider the current context
kcov_common_handle is a method that is used to obtain a "default" KCOV
remote handle of the current process. The handle can later be passed
to kcov_remote_start in order to collect coverage for the processing
that is initiated by one process, but done in another. For details see
Documentation/dev-tools/kcov.rst and comments in kernel/kcov.c.
Presently, if kcov_common_handle is called in an IRQ context, it will
return a handle for the interrupted process. This may lead to
unreliable and incorrect coverage collection.
Adjust the behavior of kcov_common_handle in the following way. If it
is called in a task context, return the common handle for the
currently running task. Otherwise, return 0.
Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | kernel/kcov.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/kcov.c b/kernel/kcov.c index 6b8368be89c8..80bfe71bbe13 100644 --- a/kernel/kcov.c +++ b/kernel/kcov.c @@ -1023,6 +1023,8 @@ EXPORT_SYMBOL(kcov_remote_stop); /* See the comment before kcov_remote_start() for usage details. */ u64 kcov_common_handle(void) { + if (!in_task()) + return 0; return current->kcov_handle; } EXPORT_SYMBOL(kcov_common_handle); |