On 2019/5/18 0:18, Corey Minyard wrote: > On Fri, May 17, 2019 at 06:12:44PM +0800, Kefeng Wang wrote: >> If ipmi_si_platform_init()->platform_driver_register() fails, >> platform_driver_unregister() called unconditionally will trigger >> following warning, >> >> ipmi_platform: Unable to register driver: -12 >> ------------[ cut here ]------------ >> Unexpected driver unregister! >> WARNING: CPU: 1 PID: 7210 at drivers/base/driver.c:193 >> driver_unregister+0x60/0x70 drivers/base/driver.c:193 >> >> Fix it by adding platform_registered variable, only unregister platform >> driver when it is already successfully registered. > This is good, but have you found out why the driver was unable to > register in the first place? That really shouldn't happen.
Yes, it is hard to happen inĀ real scene, the test robot found this issue when FAULT_INJECTION enabled. > > This patch is queued for 5.3. > > -corey > >> Reported-by: Hulk Robot <hul...@huawei.com> >> Signed-off-by: Kefeng Wang <wangkefeng.w...@huawei.com> >> --- >> drivers/char/ipmi/ipmi_si_platform.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/char/ipmi/ipmi_si_platform.c >> b/drivers/char/ipmi/ipmi_si_platform.c >> index f2a91c4d8cab..0cd849675d99 100644 >> --- a/drivers/char/ipmi/ipmi_si_platform.c >> +++ b/drivers/char/ipmi/ipmi_si_platform.c >> @@ -19,6 +19,7 @@ >> #include "ipmi_si.h" >> #include "ipmi_dmi.h" >> >> +static bool platform_registered; >> static bool si_tryplatform = true; >> #ifdef CONFIG_ACPI >> static bool si_tryacpi = true; >> @@ -469,9 +470,12 @@ void ipmi_si_platform_init(void) >> int rv = platform_driver_register(&ipmi_platform_driver); >> if (rv) >> pr_err("Unable to register driver: %d\n", rv); >> + else >> + platform_registered = true; >> } >> >> void ipmi_si_platform_shutdown(void) >> { >> - platform_driver_unregister(&ipmi_platform_driver); >> + if (platform_registered) >> + platform_driver_unregister(&ipmi_platform_driver); >> } >> -- >> 2.20.1 >> > . >