On Tue, Oct 22, 2019 at 10:29:12AM -0400, Tony Camuso wrote: > Corey, > > Testing shows that this patch works as expected.
Thanks, I'll add a Tested-by for you. It's queued for the next merge window. -corey > > Regards, > Tony > > > On 10/14/19 11:46 AM, miny...@acm.org wrote: > > From: Corey Minyard <cminy...@mvista.com> > > > > If something has the IPMI driver open, don't allow the device > > module to be unloaded. Before it would unload and the user would > > get errors on use. > > > > This change is made on user request, and it makes it consistent > > with the I2C driver, which has the same behavior. > > > > It does change things a little bit with respect to kernel users. > > If the ACPI or IPMI watchdog (or any other kernel user) has > > created a user, then the device module cannot be unloaded. Before > > it could be unloaded, > > > > This does not affect hot-plug. If the device goes away (it's on > > something removable that is removed or is hot-removed via sysfs) > > then it still behaves as it did before. > > > > Reported-by: tony camuso <tcam...@redhat.com> > > Signed-off-by: Corey Minyard <cminy...@mvista.com> > > --- > > Tony, here is a suggested change for this. Can you look it over and > > see if it looks ok? > > > > Thanks, > > > > -corey > > > > drivers/char/ipmi/ipmi_msghandler.c | 23 ++++++++++++++++------- > > include/linux/ipmi_smi.h | 12 ++++++++---- > > 2 files changed, 24 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/char/ipmi/ipmi_msghandler.c > > b/drivers/char/ipmi/ipmi_msghandler.c > > index 2aab80e19ae0..15680de18625 100644 > > --- a/drivers/char/ipmi/ipmi_msghandler.c > > +++ b/drivers/char/ipmi/ipmi_msghandler.c > > @@ -448,6 +448,8 @@ enum ipmi_stat_indexes { > > #define IPMI_IPMB_NUM_SEQ 64 > > struct ipmi_smi { > > + struct module *owner; > > + > > /* What interface number are we? */ > > int intf_num; > > @@ -1220,6 +1222,11 @@ int ipmi_create_user(unsigned int if_num, > > if (rv) > > goto out_kfree; > > + if (!try_module_get(intf->owner)) { > > + rv = -ENODEV; > > + goto out_kfree; > > + } > > + > > /* Note that each existing user holds a refcount to the interface. */ > > kref_get(&intf->refcount); > > @@ -1349,6 +1356,7 @@ static void _ipmi_destroy_user(struct ipmi_user *user) > > } > > kref_put(&intf->refcount, intf_free); > > + module_put(intf->owner); > > } > > int ipmi_destroy_user(struct ipmi_user *user) > > @@ -2459,7 +2467,7 @@ static int __get_device_id(struct ipmi_smi *intf, > > struct bmc_device *bmc) > > * been recently fetched, this will just use the cached data. Otherwise > > * it will run a new fetch. > > * > > - * Except for the first time this is called (in ipmi_register_smi()), > > + * Except for the first time this is called (in ipmi_add_smi()), > > * this will always return good data; > > */ > > static int __bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device > > *bmc, > > @@ -3377,10 +3385,11 @@ static void redo_bmc_reg(struct work_struct *work) > > kref_put(&intf->refcount, intf_free); > > } > > -int ipmi_register_smi(const struct ipmi_smi_handlers *handlers, > > - void *send_info, > > - struct device *si_dev, > > - unsigned char slave_addr) > > +int ipmi_add_smi(struct module *owner, > > + const struct ipmi_smi_handlers *handlers, > > + void *send_info, > > + struct device *si_dev, > > + unsigned char slave_addr) > > { > > int i, j; > > int rv; > > @@ -3406,7 +3415,7 @@ int ipmi_register_smi(const struct ipmi_smi_handlers > > *handlers, > > return rv; > > } > > - > > + intf->owner = owner; > > intf->bmc = &intf->tmp_bmc; > > INIT_LIST_HEAD(&intf->bmc->intfs); > > mutex_init(&intf->bmc->dyn_mutex); > > @@ -3514,7 +3523,7 @@ int ipmi_register_smi(const struct ipmi_smi_handlers > > *handlers, > > return rv; > > } > > -EXPORT_SYMBOL(ipmi_register_smi); > > +EXPORT_SYMBOL(ipmi_add_smi); > > static void deliver_smi_err_response(struct ipmi_smi *intf, > > struct ipmi_smi_msg *msg, > > diff --git a/include/linux/ipmi_smi.h b/include/linux/ipmi_smi.h > > index 4dc66157d872..deec18b8944a 100644 > > --- a/include/linux/ipmi_smi.h > > +++ b/include/linux/ipmi_smi.h > > @@ -224,10 +224,14 @@ static inline int ipmi_demangle_device_id(uint8_t > > netfn, uint8_t cmd, > > * is called, and the lower layer must get the interface from that > > * call. > > */ > > -int ipmi_register_smi(const struct ipmi_smi_handlers *handlers, > > - void *send_info, > > - struct device *dev, > > - unsigned char slave_addr); > > +int ipmi_add_smi(struct module *owner, > > + const struct ipmi_smi_handlers *handlers, > > + void *send_info, > > + struct device *dev, > > + unsigned char slave_addr); > > + > > +#define ipmi_register_smi(handlers, send_info, dev, slave_addr) \ > > + ipmi_add_smi(THIS_MODULE, handlers, send_info, dev, slave_addr) > > /* > > * Remove a low-level interface from the IPMI driver. This will > > >