[PATCH] genirq/irqdesc: fix WARNING in irq_sysfs_del()

From: Yang Yingliang
Date: Sat Nov 26 2022 - 03:29:18 EST


I got the lots of WARNING report when doing fault injection test:

kernfs: can not remove 'chip_name', no directory
WARNING: CPU: 0 PID: 253 at fs/kernfs/dir.c:1616 kernfs_remove_by_name_ns+0xce/0xe0
RIP: 0010:kernfs_remove_by_name_ns+0xce/0xe0
Call Trace:
<TASK>
remove_files.isra.1+0x3f/0xb0
sysfs_remove_group+0x68/0xe0
sysfs_remove_groups+0x41/0x70
__kobject_del+0x45/0xc0
kobject_del+0x29/0x40
free_desc+0x42/0x70
irq_free_descs+0x5e/0x90

kernfs: can not remove 'hwirq', no directory
WARNING: CPU: 0 PID: 253 at fs/kernfs/dir.c:1616 kernfs_remove_by_name_ns+0xce/0xe0
RIP: 0010:kernfs_remove_by_name_ns+0xce/0xe0
Call Trace:
<TASK>
remove_files.isra.1+0x3f/0xb0
sysfs_remove_group+0x68/0xe0
sysfs_remove_groups+0x41/0x70
__kobject_del+0x45/0xc0
kobject_del+0x29/0x40
free_desc+0x42/0x70
irq_free_descs+0x5e/0x90

If irq_sysfs_add() fails in alloc_descs(), the directory of interrupt
informations is not added to sysfs, it causes the WARNINGs when removing
the information files. Fix this by adding check kobj.state_in_sysfs in
irq_sysfs_del().

Fixes: ecb3f394c5db ("genirq: Expose interrupt information through sysfs")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
kernel/irq/irqdesc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index a91f9001103c..e391f4195b87 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -303,7 +303,7 @@ static void irq_sysfs_del(struct irq_desc *desc)
* kobject_del() complains about a object with no parent, so make
* it conditional.
*/
- if (irq_kobj_base)
+ if (irq_kobj_base && desc->kobj.state_in_sysfs)
kobject_del(&desc->kobj);
}

--
2.25.1