[tip:irq/core] genirq/debugfs: Reset domain debugfs_file on removal of the debugfs file

[tip-bot for Marc Zyngier]

Commit-ID:  513145ea66af95f1a5c744d7b5a4f4a97625e669
Gitweb:     https://git.kernel.org/tip/513145ea66af95f1a5c744d7b5a4f4a97625e669
Author:     Marc Zyngier <marc.zyngier@xxxxxxx>
AuthorDate: Mon, 1 Oct 2018 11:05:21 +0100
Committer:  Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Mon, 1 Oct 2018 12:24:53 +0200

genirq/debugfs: Reset domain debugfs_file on removal of the debugfs file

When removing a debugfs file for a given irq domain, we fail to clear the
corresponding field, meaning that the corresponding domain won't be created
again if we need to do so.

It turns out that this is exactly what irq_domain_update_bus_token does
(delete old file, update domain name, recreate file).

This doesn't have any impact other than making debug more difficult, but we
do value ease of debugging... So clear the debugfs_file field.

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20181001100522.180054-2-marc.zyngier@xxxxxxx

---
 kernel/irq/irqdomain.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 5d9fc01b60a6..95a0acbdd4e6 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1741,6 +1741,7 @@ static void debugfs_add_domain_dir(struct irq_domain *d)
 static void debugfs_remove_domain_dir(struct irq_domain *d)
 {
 	debugfs_remove(d->debugfs_file);
+	d->debugfs_file = NULL;
 }
 
 void __init irq_domain_debugfs_init(struct dentry *root)