Re: [PATCH] x86/itmt: Don't make ITMT enablement depend on debugfs
From: K Prateek Nayak
Date: Tue Aug 11 2026 - 13:20:22 EST
Hello Mario,
On 8/11/2026 8:06 PM, Mario Limonciello wrote:
> sched_set_itmt_support() treats debugfs file creation failures as fatal.
> When CONFIG_DEBUG_FS is disabled, debugfs stubs return ERR_PTR(-ENODEV),
> causing ITMT to be silently disabled.
>
> debugfs is a debug-only facility; its return values should be ignored.
> Drop the fatal error handling and enable ITMT unconditionally.
>
> Fixes: d04013a4b21b ("x86/itmt: Move the "sched_itmt_enabled" sysctl to debugfs")
> Reported-by: Klaus Kusche <klaus.kusche@xxxxxxxxxxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
Feel free to include:
Reviewed-by: K Prateek Nayak <kprateek.nayak@xxxxxxx>
> ---
> arch/x86/kernel/itmt.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/kernel/itmt.c b/arch/x86/kernel/itmt.c
> index 243a769fdd97b..85ebde361d6ae 100644
> --- a/arch/x86/kernel/itmt.c
> +++ b/arch/x86/kernel/itmt.c
> @@ -110,18 +110,14 @@ int sched_set_itmt_support(void)
> arch_debugfs_dir,
> &sysctl_sched_itmt_enabled,
> &dfs_sched_itmt_fops);
> - if (IS_ERR_OR_NULL(dfs_sched_itmt)) {
> + if (IS_ERR(dfs_sched_itmt))
> dfs_sched_itmt = NULL;
> - return -ENOMEM;
> - }
>
> dfs_sched_core_prio = debugfs_create_file("sched_core_priority", 0644,
> arch_debugfs_dir, NULL,
> &sched_core_priority_fops);
> - if (IS_ERR_OR_NULL(dfs_sched_core_prio)) {
> + if (IS_ERR(dfs_sched_core_prio))
> dfs_sched_core_prio = NULL;
> - return -ENOMEM;
> - }
>
> sched_itmt_capable = true;
>
--
Thanks and Regards,
Prateek