From: Kefeng Wang wangkefeng.wang@huawei.com
[ Upstream commit 50710eeefbc1ed25375942aad0c4d1eb4af0f330 ]
if saa7164_proc_create() fails, saa7164_fini() will trigger a warning,
name 'saa7164' WARNING: CPU: 1 PID: 6311 at fs/proc/generic.c:672 remove_proc_entry+0x1e8/0x3a0 ? remove_proc_entry+0x1e8/0x3a0 ? try_stop_module+0x7b/0x240 ? proc_readdir+0x70/0x70 ? rcu_read_lock_sched_held+0xd7/0x100 saa7164_fini+0x13/0x1f [saa7164] __x64_sys_delete_module+0x30c/0x480 ? __ia32_sys_delete_module+0x480/0x480 ? __x64_sys_clock_gettime+0x11e/0x1c0 ? __x64_sys_timer_create+0x1a0/0x1a0 ? trace_hardirqs_off_caller+0x40/0x180 ? do_syscall_64+0x18/0x450 do_syscall_64+0x9f/0x450 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fix it by checking the return of proc_create_single() before calling remove_proc_entry().
Signed-off-by: Kefeng Wang wangkefeng.wang@huawei.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl [hverkuil-cisco@xs4all.nl: use 0444 instead of S_IRUGO] [hverkuil-cisco@xs4all.nl: use pr_info instead of KERN_INFO] Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/pci/saa7164/saa7164-core.c | 33 ++++++++++++++++-------- 1 file changed, 22 insertions(+), 11 deletions(-)
diff --git a/drivers/media/pci/saa7164/saa7164-core.c b/drivers/media/pci/saa7164/saa7164-core.c index c594aff92e70..9ae04e18e6c6 100644 --- a/drivers/media/pci/saa7164/saa7164-core.c +++ b/drivers/media/pci/saa7164/saa7164-core.c @@ -1112,16 +1112,25 @@ static int saa7164_proc_show(struct seq_file *m, void *v) return 0; }
+static struct proc_dir_entry *saa7164_pe; + static int saa7164_proc_create(void) { - struct proc_dir_entry *pe; - - pe = proc_create_single("saa7164", S_IRUGO, NULL, saa7164_proc_show); - if (!pe) + saa7164_pe = proc_create_single("saa7164", 0444, NULL, saa7164_proc_show); + if (!saa7164_pe) return -ENOMEM;
return 0; } + +static void saa7164_proc_destroy(void) +{ + if (saa7164_pe) + remove_proc_entry("saa7164", NULL); +} +#else +static int saa7164_proc_create(void) { return 0; } +static void saa7164_proc_destroy(void) {} #endif
static int saa7164_thread_function(void *data) @@ -1493,19 +1502,21 @@ static struct pci_driver saa7164_pci_driver = {
static int __init saa7164_init(void) { - printk(KERN_INFO "saa7164 driver loaded\n"); + int ret = pci_register_driver(&saa7164_pci_driver); + + if (ret) + return ret;
-#ifdef CONFIG_PROC_FS saa7164_proc_create(); -#endif - return pci_register_driver(&saa7164_pci_driver); + + pr_info("saa7164 driver loaded\n"); + + return 0; }
static void __exit saa7164_fini(void) { -#ifdef CONFIG_PROC_FS - remove_proc_entry("saa7164", NULL); -#endif + saa7164_proc_destroy(); pci_unregister_driver(&saa7164_pci_driver); }