From 2cd7a1c6dcd33e7c1a82b254871230f29866d4e9 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Sat, 10 Mar 2018 06:14:52 -0800 Subject: [PATCH] firmware: enable to force disable the fallback mechanism at run time You currently need four different kernel builds to test the firmware API fully. By adding a proc knob to force disable the fallback mechanism completely we are able to reduce the amount of kernels you need built to test the firmware API down to two. Acked-by: Kees Cook Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 5 +++++ drivers/base/firmware_loader/fallback.h | 4 ++++ drivers/base/firmware_loader/fallback_table.c | 9 +++++++++ 3 files changed, 18 insertions(+) diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 45cc40933a47..d6838e7ec00c 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -643,6 +643,11 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) static bool fw_run_sysfs_fallback(unsigned int opt_flags) { + if (fw_fallback_config.ignore_sysfs_fallback) { + pr_info_once("Ignoring firmware sysfs fallback due to debugfs knob\n"); + return false; + } + if ((opt_flags & FW_OPT_NOFALLBACK)) return false; diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h index ca7e69a8417b..dfebc644ed35 100644 --- a/drivers/base/firmware_loader/fallback.h +++ b/drivers/base/firmware_loader/fallback.h @@ -14,12 +14,16 @@ * 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. + * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism. + * This emulates the behaviour as if we had set the kernel + * config CONFIG_FW_LOADER_USER_HELPER=n. * @old_timeout: for internal use * @loading_timeout: the timeout to wait for the fallback mechanism before * giving up, in seconds. */ struct firmware_fallback_config { unsigned int force_sysfs_fallback; + unsigned int ignore_sysfs_fallback; int old_timeout; int loading_timeout; }; diff --git a/drivers/base/firmware_loader/fallback_table.c b/drivers/base/firmware_loader/fallback_table.c index 92365e053e30..7428659d8df9 100644 --- a/drivers/base/firmware_loader/fallback_table.c +++ b/drivers/base/firmware_loader/fallback_table.c @@ -39,6 +39,15 @@ struct ctl_table firmware_config_table[] = { .extra1 = &zero, .extra2 = &one, }, + { + .procname = "ignore_sysfs_fallback", + .data = &fw_fallback_config.ignore_sysfs_fallback, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, { } }; EXPORT_SYMBOL_GPL(firmware_config_table);