Hi Dawei,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on xen-tip/linux-next]
[also build test WARNING on linus/master v6.1-rc8 next-20221205]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Dawei-Li/hyperv-Make-remove-callback-of-hyperv-driver-void-returned/20221205-233927
base:   https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next
patch link:    https://lore.kernel.org/r/TYCP286MB232373567792ED1AC5E0849FCA189%40TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
patch subject: [PATCH 1/6] hyperv: Make remove callback of hyperv driver void returned
config: x86_64-rhel-8.3-syz
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/19dc60f1e539ba31e531b89e5f57b9ce584be2f1
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Dawei-Li/hyperv-Make-remove-callback-of-hyperv-driver-void-returned/20221205-233927
        git checkout 19dc60f1e539ba31e531b89e5f57b9ce584be2f1
        # 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/pci/controller/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot [off-list ref]

All warnings (new ones prefixed by >>):

   drivers/pci/controller/pci-hyperv.c: In function 'hv_pci_remove':

quoted

drivers/pci/controller/pci-hyperv.c:3822:13: warning: variable 'ret' set but not used [-Wunused-but-set-variable]

    3822 |         int ret;
         |             ^~~


vim +/ret +3822 drivers/pci/controller/pci-hyperv.c

17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3812  
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3813  /**
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3814   * hv_pci_remove() - Remove routine for this VMBus channel
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3815   * @hdev:	VMBus's tracking struct for this root PCI bus
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3816   *
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3817   * Return: 0 on success, -errno on failure
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3818   */
19dc60f1e539ba3 drivers/pci/controller/pci-hyperv.c Dawei Li         2022-12-05  3819  static void hv_pci_remove(struct hv_device *hdev)
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3820  {
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3821  	struct hv_pcibus_device *hbus;
a8e37506e79a7a0 drivers/pci/controller/pci-hyperv.c Dexuan Cui       2019-11-24 @3822  	int ret;
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3823  
17978524a636d00 drivers/pci/host/pci-hyperv.c       Dexuan Cui       2016-11-10  3824  	hbus = hv_get_drvdata(hdev);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3825  	if (hbus->state == hv_pcibus_installed) {
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3826  		tasklet_disable(&hdev->channel->callback_event);
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3827  		hbus->state = hv_pcibus_removing;
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3828  		tasklet_enable(&hdev->channel->callback_event);
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3829  		destroy_workqueue(hbus->wq);
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3830  		hbus->wq = NULL;
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3831  		/*
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3832  		 * At this point, no work is running or can be scheduled
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3833  		 * on hbus-wq. We can't race with hv_pci_devices_present()
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3834  		 * or hv_pci_eject_device(), it's safe to proceed.
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3835  		 */
94d22763207ac66 drivers/pci/controller/pci-hyperv.c Long Li          2021-05-12  3836  
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3837  		/* Remove the bus from PCI's point of view. */
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3838  		pci_lock_rescan_remove();
418cb6c8e051119 drivers/pci/controller/pci-hyperv.c Arnd Bergmann    2021-07-27  3839  		pci_stop_root_bus(hbus->bridge->bus);
15becc2b56c6eda drivers/pci/controller/pci-hyperv.c Dexuan Cui       2019-03-04  3840  		hv_pci_remove_slots(hbus);
418cb6c8e051119 drivers/pci/controller/pci-hyperv.c Arnd Bergmann    2021-07-27  3841  		pci_remove_root_bus(hbus->bridge->bus);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3842  		pci_unlock_rescan_remove();
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3843  	}
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3844  
a8e37506e79a7a0 drivers/pci/controller/pci-hyperv.c Dexuan Cui       2019-11-24  3845  	ret = hv_pci_bus_exit(hdev, false);
deb22e5c84c884a drivers/pci/host/pci-hyperv.c       Vitaly Kuznetsov 2016-04-29  3846  
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3847  	vmbus_close(hdev->channel);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3848  
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3849  	iounmap(hbus->cfg_addr);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3850  	hv_free_config_window(hbus);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3851  	hv_pci_free_bridge_windows(hbus);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3852  	irq_domain_remove(hbus->irq_domain);
9e7f9178ab4943b drivers/pci/controller/pci-hyperv.c Boqun Feng       2021-07-27  3853  	irq_domain_free_fwnode(hbus->fwnode);
be700103efd1050 drivers/pci/controller/pci-hyperv.c Haiyang Zhang    2019-08-15  3854  
38c0d266dc80b81 drivers/pci/controller/pci-hyperv.c Boqun Feng       2021-07-27  3855  	hv_put_dom_num(hbus->bridge->domain_nr);
be700103efd1050 drivers/pci/controller/pci-hyperv.c Haiyang Zhang    2019-08-15  3856  
877b911a5ba0733 drivers/pci/controller/pci-hyperv.c Dexuan Cui       2019-11-24  3857  	kfree(hbus);
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3858  }
4daace0d8ce851f drivers/pci/host/pci-hyperv.c       Jake Oshins      2016-02-16  3859  

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