After writing "4" to /proc/sys/vm/drop_caches there was no way to re-enable the drop_caches kernel message. By removing the "or" logic for the stfu variable in drop_cache_sysctl_handler, it is now possible to toggle the message on and off by setting the 4th bit in /proc/sys/vm/drop_caches. Signed-off-by: Joel Granados <joel.granados@xxxxxxxxxx> --- Documentation/admin-guide/sysctl/vm.rst | 2 +- fs/drop_caches.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index f48eaa98d22d2b575f6e913f437b0d548daac3e6..75a032f8cbfb4e05f04610cca219d154bd852789 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -266,7 +266,7 @@ used:: cat (1234): drop_caches: 3 These are informational only. They do not mean that anything is wrong -with your system. To disable them, echo 4 (bit 2) into drop_caches. +with your system. To toggle them, echo 4 (bit 2) into drop_caches. enable_soft_offline =================== diff --git a/fs/drop_caches.c b/fs/drop_caches.c index d45ef541d848a73cbd19205e0111c2cab3b73617..501b9f690445e245f88cbb31a5123b2752e2e7ce 100644 --- a/fs/drop_caches.c +++ b/fs/drop_caches.c @@ -73,7 +73,7 @@ int drop_caches_sysctl_handler(const struct ctl_table *table, int write, current->comm, task_pid_nr(current), sysctl_drop_caches); } - stfu |= sysctl_drop_caches & 4; + stfu = sysctl_drop_caches & 4; } return 0; } --- base-commit: 7eb172143d5508b4da468ed59ee857c6e5e01da6 change-id: 20250313-jag-drop_caches_msg-c4fbfedb51f3 Best regards, -- Joel Granados <joel.granados@xxxxxxxxxx>
