| Message ID | 20231129065748.19871-2-quic_sibis@quicinc.com |
|---|---|
| State | Accepted |
| Commit | 3cc12bb83e6794de7f50799ce43d85c7a3d55828 |
| Headers | show |
| Series | firmware: arm_scmi: Miscellaneous fixes and opp count increase | expand |
On Wed, Nov 29, 2023 at 12:27:46PM +0530, Sibi Sankar wrote: > The scmi_perf_domain_lookup requires the protocol handle to have the > private data set, which is yet to happen during the fastchannel init > scenario. This results in a null pointer dereference. Fix this by using > the pre-populated perf_dom_info to pass on the required information > instead. > > Call trace: > scmi_perf_protocol_init+0x434/0x678 > scmi_get_protocol_instance+0x168/0x29c > scmi_devres_protocol_instance_get+0x50/0xa0 > scmi_devm_protocol_get+0x20/0x50 > scmi_cpufreq_probe+0x34/0xd4 > scmi_dev_probe+0x28/0x3c > really_probe+0x148/0x2ac > __driver_probe_device+0x78/0x12c > driver_probe_device+0x40/0x160 > __device_attach_driver+0xb8/0x134 > bus_for_each_drv+0x80/0xdc > __device_attach+0xa8/0x1b0 > device_initial_probe+0x14/0x20 > bus_probe_device+0xa8/0xac > device_add+0x5cc/0x778 > device_register+0x20/0x30 > __scmi_device_create.part.0+0xec/0x1cc > scmi_device_create+0x180/0x1c4 > scmi_create_protocol_devices+0x4c/0xb0 > scmi_probe+0x660/0x738 > platform_probe+0x68/0xdc > really_probe+0x148/0x2ac > __driver_probe_device+0x78/0x12c > driver_probe_device+0x40/0x160 > __device_attach_driver+0xb8/0x134 > bus_for_each_drv+0x80/0xdc > __device_attach+0xa8/0x1b0 > device_initial_probe+0x14/0x20 > bus_probe_device+0xa8/0xac > deferred_probe_work_func+0x88/0xc0 > process_one_work+0x13c/0x264 > worker_thread+0x32c/0x438 > kthread+0x118/0x11c > ret_from_fork+0x10/0x20 > > Fixes: 619bc6e034f3 ("firmware: arm_scmi: Populate fastchannel info only if set operations are allowed") > Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com> > --- Yes indeed, I made this same error in the past and then I missed it when reviewing the offending patch :< ... Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Thanks, Cristian > drivers/firmware/arm_scmi/perf.c | 19 +++++++------------ > 1 file changed, 7 insertions(+), 12 deletions(-) > > diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c > index d1323c5d9c27..a648521e04a3 100644 > --- a/drivers/firmware/arm_scmi/perf.c > +++ b/drivers/firmware/arm_scmi/perf.c > @@ -759,40 +759,35 @@ static int scmi_perf_level_limits_notify(const struct scmi_protocol_handle *ph, > } > > static void scmi_perf_domain_init_fc(const struct scmi_protocol_handle *ph, > - u32 domain, struct scmi_fc_info **p_fc) > + struct perf_dom_info *dom) > { > struct scmi_fc_info *fc; > - struct perf_dom_info *dom; > - > - dom = scmi_perf_domain_lookup(ph, domain); > - if (IS_ERR(dom)) > - return; > > fc = devm_kcalloc(ph->dev, PERF_FC_MAX, sizeof(*fc), GFP_KERNEL); > if (!fc) > return; > > ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, > - PERF_LEVEL_GET, 4, domain, > + PERF_LEVEL_GET, 4, dom->id, > &fc[PERF_FC_LEVEL].get_addr, NULL); > > ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, > - PERF_LIMITS_GET, 8, domain, > + PERF_LIMITS_GET, 8, dom->id, > &fc[PERF_FC_LIMIT].get_addr, NULL); > > if (dom->info.set_perf) > ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, > - PERF_LEVEL_SET, 4, domain, > + PERF_LEVEL_SET, 4, dom->id, > &fc[PERF_FC_LEVEL].set_addr, > &fc[PERF_FC_LEVEL].set_db); > > if (dom->set_limits) > ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, > - PERF_LIMITS_SET, 8, domain, > + PERF_LIMITS_SET, 8, dom->id, > &fc[PERF_FC_LIMIT].set_addr, > &fc[PERF_FC_LIMIT].set_db); > > - *p_fc = fc; > + dom->fc_info = fc; > } > > static int scmi_dvfs_device_opps_add(const struct scmi_protocol_handle *ph, > @@ -1102,7 +1097,7 @@ static int scmi_perf_protocol_init(const struct scmi_protocol_handle *ph) > scmi_perf_describe_levels_get(ph, dom, version); > > if (dom->perf_fastchannels) > - scmi_perf_domain_init_fc(ph, dom->id, &dom->fc_info); > + scmi_perf_domain_init_fc(ph, dom); > } > > ret = devm_add_action_or_reset(ph->dev, scmi_perf_xa_destroy, pinfo); > -- > 2.17.1 >
diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c index d1323c5d9c27..a648521e04a3 100644 --- a/drivers/firmware/arm_scmi/perf.c +++ b/drivers/firmware/arm_scmi/perf.c @@ -759,40 +759,35 @@ static int scmi_perf_level_limits_notify(const struct scmi_protocol_handle *ph, } static void scmi_perf_domain_init_fc(const struct scmi_protocol_handle *ph, - u32 domain, struct scmi_fc_info **p_fc) + struct perf_dom_info *dom) { struct scmi_fc_info *fc; - struct perf_dom_info *dom; - - dom = scmi_perf_domain_lookup(ph, domain); - if (IS_ERR(dom)) - return; fc = devm_kcalloc(ph->dev, PERF_FC_MAX, sizeof(*fc), GFP_KERNEL); if (!fc) return; ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, - PERF_LEVEL_GET, 4, domain, + PERF_LEVEL_GET, 4, dom->id, &fc[PERF_FC_LEVEL].get_addr, NULL); ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, - PERF_LIMITS_GET, 8, domain, + PERF_LIMITS_GET, 8, dom->id, &fc[PERF_FC_LIMIT].get_addr, NULL); if (dom->info.set_perf) ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, - PERF_LEVEL_SET, 4, domain, + PERF_LEVEL_SET, 4, dom->id, &fc[PERF_FC_LEVEL].set_addr, &fc[PERF_FC_LEVEL].set_db); if (dom->set_limits) ph->hops->fastchannel_init(ph, PERF_DESCRIBE_FASTCHANNEL, - PERF_LIMITS_SET, 8, domain, + PERF_LIMITS_SET, 8, dom->id, &fc[PERF_FC_LIMIT].set_addr, &fc[PERF_FC_LIMIT].set_db); - *p_fc = fc; + dom->fc_info = fc; } static int scmi_dvfs_device_opps_add(const struct scmi_protocol_handle *ph, @@ -1102,7 +1097,7 @@ static int scmi_perf_protocol_init(const struct scmi_protocol_handle *ph) scmi_perf_describe_levels_get(ph, dom, version); if (dom->perf_fastchannels) - scmi_perf_domain_init_fc(ph, dom->id, &dom->fc_info); + scmi_perf_domain_init_fc(ph, dom); } ret = devm_add_action_or_reset(ph->dev, scmi_perf_xa_destroy, pinfo);
The scmi_perf_domain_lookup requires the protocol handle to have the private data set, which is yet to happen during the fastchannel init scenario. This results in a null pointer dereference. Fix this by using the pre-populated perf_dom_info to pass on the required information instead. Call trace: scmi_perf_protocol_init+0x434/0x678 scmi_get_protocol_instance+0x168/0x29c scmi_devres_protocol_instance_get+0x50/0xa0 scmi_devm_protocol_get+0x20/0x50 scmi_cpufreq_probe+0x34/0xd4 scmi_dev_probe+0x28/0x3c really_probe+0x148/0x2ac __driver_probe_device+0x78/0x12c driver_probe_device+0x40/0x160 __device_attach_driver+0xb8/0x134 bus_for_each_drv+0x80/0xdc __device_attach+0xa8/0x1b0 device_initial_probe+0x14/0x20 bus_probe_device+0xa8/0xac device_add+0x5cc/0x778 device_register+0x20/0x30 __scmi_device_create.part.0+0xec/0x1cc scmi_device_create+0x180/0x1c4 scmi_create_protocol_devices+0x4c/0xb0 scmi_probe+0x660/0x738 platform_probe+0x68/0xdc really_probe+0x148/0x2ac __driver_probe_device+0x78/0x12c driver_probe_device+0x40/0x160 __device_attach_driver+0xb8/0x134 bus_for_each_drv+0x80/0xdc __device_attach+0xa8/0x1b0 device_initial_probe+0x14/0x20 bus_probe_device+0xa8/0xac deferred_probe_work_func+0x88/0xc0 process_one_work+0x13c/0x264 worker_thread+0x32c/0x438 kthread+0x118/0x11c ret_from_fork+0x10/0x20 Fixes: 619bc6e034f3 ("firmware: arm_scmi: Populate fastchannel info only if set operations are allowed") Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com> --- drivers/firmware/arm_scmi/perf.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-)