Linux 6.5 compat: spl: properly unregister sysctl entries

When register_sysctl_table() is unavailable we fail to properly
unregister sysctl entries under "kernel/spl".

This leads to errors like the following when spl is unloaded/reloaded,
making impossible to properly reload the spl module:

[  746.995704] sysctl duplicate entry: /kernel/spl/kmem/slab_kvmem_total

Fix by cleaning up all the sub-entries inside "kernel/spl" when the
spl module is unloaded.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Closes #15239
This commit is contained in:
Andrea Righi 2023-09-07 23:36:32 +02:00 committed by Brian Behlendorf
parent c7ee59a160
commit cacc599aa2

View File

@ -47,6 +47,10 @@ static unsigned long table_min = 0;
static unsigned long table_max = ~0;
static struct ctl_table_header *spl_header = NULL;
#ifndef HAVE_REGISTER_SYSCTL_TABLE
static struct ctl_table_header *spl_kmem = NULL;
static struct ctl_table_header *spl_kstat = NULL;
#endif
static struct proc_dir_entry *proc_spl = NULL;
static struct proc_dir_entry *proc_spl_kmem = NULL;
static struct proc_dir_entry *proc_spl_kmem_slab = NULL;
@ -668,6 +672,16 @@ static void spl_proc_cleanup(void)
remove_proc_entry("taskq", proc_spl);
remove_proc_entry("spl", NULL);
#ifndef HAVE_REGISTER_SYSCTL_TABLE
if (spl_kstat) {
unregister_sysctl_table(spl_kstat);
spl_kstat = NULL;
}
if (spl_kmem) {
unregister_sysctl_table(spl_kmem);
spl_kmem = NULL;
}
#endif
if (spl_header) {
unregister_sysctl_table(spl_header);
spl_header = NULL;
@ -688,12 +702,13 @@ spl_proc_init(void)
if (spl_header == NULL)
return (-EUNATCH);
if (register_sysctl("kernel/spl/kmem", spl_kmem_table) == NULL) {
spl_kmem = register_sysctl("kernel/spl/kmem", spl_kmem_table);
if (spl_kmem == NULL) {
rc = -EUNATCH;
goto out;
}
if (register_sysctl("kernel/spl/kstat", spl_kstat_table) == NULL) {
spl_kstat = register_sysctl("kernel/spl/kstat", spl_kstat_table);
if (spl_kstat == NULL) {
rc = -EUNATCH;
goto out;
}