Hi Elliot, I love your patch! Perhaps something to improve: [auto build test WARNING on 094226ad94f471a9f19e8f8e7140a09c2625abaa] url: https://github.com/intel-lab-lkp/linux/commits/Elliot-Berman/Drivers-for-gunyah-hypervisor/20221121-220942 base: 094226ad94f471a9f19e8f8e7140a09c2625abaa patch link: https://lore.kernel.org/r/20221121140009.2353512-8-quic_eberman%40quicinc.com patch subject: [PATCH v7 07/20] mailbox: Allow direct registration to a channel config: x86_64-allyesconfig compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/5b7d4244a3896cfa8c098f01bee924c3ea869884 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Elliot-Berman/Drivers-for-gunyah-hypervisor/20221121-220942 git checkout 5b7d4244a3896cfa8c098f01bee924c3ea869884 # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/mailbox/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot All warnings (new ones prefixed by >>): drivers/mailbox/pcc.c: In function 'pcc_mbox_request_channel': >> drivers/mailbox/pcc.c:286:23: warning: unused variable 'flags' [-Wunused-variable] 286 | unsigned long flags; | ^~~~~ vim +/flags +286 drivers/mailbox/pcc.c aca314efb177274 hotran 2016-08-15 267 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 268 /** 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 269 * pcc_mbox_request_channel - PCC clients call this function to 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 270 * request a pointer to their PCC subspace, from which they 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 271 * can get the details of communicating with the remote. 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 272 * @cl: Pointer to Mailbox client, so we know where to bind the 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 273 * Channel. 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 274 * @subspace_id: The PCC Subspace index as parsed in the PCC client 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 275 * ACPI package. This is used to lookup the array of PCC 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 276 * subspaces as parsed by the PCC Mailbox controller. 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 277 * 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 278 * Return: Pointer to the PCC Mailbox Channel if successful or ERR_PTR. 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 279 */ 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 280 struct pcc_mbox_chan * 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 281 pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id) 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 282 { 80b2bdde002c521 Sudeep Holla 2021-09-17 283 struct pcc_chan_info *pchan; 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 284 struct mbox_chan *chan; ce028702ddbc697 Sudeep Holla 2021-09-17 285 struct device *dev; 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 @286 unsigned long flags; 5b7d4244a3896cf Elliot Berman 2022-11-21 287 int rc; 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 288 ce028702ddbc697 Sudeep Holla 2021-09-17 289 if (subspace_id < 0 || subspace_id >= pcc_chan_count) 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 290 return ERR_PTR(-ENOENT); 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 291 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 292 pchan = chan_info + subspace_id; 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 293 chan = pchan->chan.mchan; d311a28a5853857 Sudip Mukherjee 2015-09-16 294 if (IS_ERR(chan) || chan->cl) { 960c4056aadcf61 Sudeep Holla 2021-12-09 295 pr_err("Channel not found for idx: %d\n", subspace_id); 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 296 return ERR_PTR(-EBUSY); 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 297 } ce028702ddbc697 Sudeep Holla 2021-09-17 298 dev = chan->mbox->dev; 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 299 5b7d4244a3896cf Elliot Berman 2022-11-21 300 rc = mbox_bind_client(chan, cl); 5b7d4244a3896cf Elliot Berman 2022-11-21 301 if (rc) 5b7d4244a3896cf Elliot Berman 2022-11-21 302 return ERR_PTR(rc); 6ca595a70bc46e1 Hoan Tran 2016-11-14 303 f92ae90e52bb09d Sudeep Holla 2021-09-17 304 if (pchan->plat_irq > 0) { f92ae90e52bb09d Sudeep Holla 2021-09-17 305 rc = devm_request_irq(dev, pchan->plat_irq, pcc_mbox_irq, 0, 80b2bdde002c521 Sudeep Holla 2021-09-17 306 MBOX_IRQ_NAME, chan); aca314efb177274 hotran 2016-08-15 307 if (unlikely(rc)) { aca314efb177274 hotran 2016-08-15 308 dev_err(dev, "failed to register PCC interrupt %d\n", f92ae90e52bb09d Sudeep Holla 2021-09-17 309 pchan->plat_irq); 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 310 pcc_mbox_free_channel(&pchan->chan); 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 311 return ERR_PTR(rc); aca314efb177274 hotran 2016-08-15 312 } aca314efb177274 hotran 2016-08-15 313 } aca314efb177274 hotran 2016-08-15 314 7b6da7fe7bba1cd Sudeep Holla 2021-09-17 315 return &pchan->chan; 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 316 } 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 317 EXPORT_SYMBOL_GPL(pcc_mbox_request_channel); 86c22f8c9a3b71d Ashwin Chaugule 2014-11-12 318 -- 0-DAY CI Kernel Test Service https://01.org/lkp