Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
e36bea6e78
`cancel_work_sync(&hdev->power_on)` was moved to hci_dev_close_sync in commit [1] to ensure that power_on work is canceled after HCI interface down. But, in certain cases power_on work function may call hci_dev_close_sync itself: hci_power_on -> hci_dev_do_close -> hci_dev_close_sync -> cancel_work_sync(&hdev->power_on), causing deadlock. In particular, this happens when device is rfkilled on boot. To avoid deadlock, move power_on work canceling out of hci_dev_do_close/hci_dev_close_sync. Deadlock introduced by commit [1] was reported in [2,3] as broken suspend. Suspend did not work because `hdev->req_lock` held as result of `power_on` work deadlock. In fact, other BT features were not working. It was not observed when testing [1] since it was verified without rfkill in place. NOTE: It is not needed to cancel power_on work from other places where hci_dev_do_close/hci_dev_close_sync is called in case: * Requests were serialized due to `hdev->req_workqueue`. The power_on work is first in that workqueue. * hci_rfkill_set_block which won't close device anyway until HCI_SETUP is on. * hci_sock_release which runs after hci_sock_bind which ensures HCI_SETUP was cleared. As result, behaviour is the same as in pre-dd06ed7 commit, except power_on work cancel added to hci_dev_close. [1]: commit |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.