firmware: enable run time change of forcing fallback loader
Currently one requires to test four kernel configurations to test the
firmware API completely:
0)
CONFIG_FW_LOADER=y
1)
o CONFIG_FW_LOADER=y
o CONFIG_FW_LOADER_USER_HELPER=y
2)
o CONFIG_FW_LOADER=y
o CONFIG_FW_LOADER_USER_HELPER=y
o CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
3) When CONFIG_FW_LOADER=m the built-in stuff is disabled, we have
no current tests for this.
We can reduce the requirements to three kernel configurations by making
fw_config.force_sysfs_fallback a proc knob we flip on off. For kernels that
disable CONFIG_IKCONFIG_PROC this can also enable one to inspect if
CONFIG_FW_LOADER_USER_HELPER_FALLBACK was enabled at build time by checking
the proc value at boot time.
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h
index 550498c..ca7e69a 100644
--- a/drivers/base/firmware_loader/fallback.h
+++ b/drivers/base/firmware_loader/fallback.h
@@ -12,12 +12,14 @@
*
* @force_sysfs_fallback: force the sysfs fallback mechanism to be used
* as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y.
+ * Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
+ * functionality on a kernel where that config entry has been disabled.
* @old_timeout: for internal use
* @loading_timeout: the timeout to wait for the fallback mechanism before
* giving up, in seconds.
*/
struct firmware_fallback_config {
- const bool force_sysfs_fallback;
+ unsigned int force_sysfs_fallback;
int old_timeout;
int loading_timeout;
};