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!)
Deadlock as below is triggered by one CPU holds drvdata->spinlock
and calls cti_enable_hw(). Smp_call_function_single() is called
in cti_enable_hw() and tries to let another CPU write CTI registers.
That CPU is trying to get drvdata->spinlock in cti_cpu_pm_notify()
and doesn't response to IPI from smp_call_function_single().
[ 988.335937] CPU: 6 PID: 10258 Comm: sh Tainted: G W L
5.8.0-rc6-mainline-16783-gc38daa79b26b-dirty #1
[ 988.346364] Hardware name: Thundercomm Dragonboard 845c (DT)
[ 988.352073] pstate: 20400005 (nzCv daif +PAN -UAO BTYPE=--)
[ 988.357689] pc : smp_call_function_single+0x158/0x1b8
[ 988.362782] lr : smp_call_function_single+0x124/0x1b8
...
[ 988.451638] Call trace:
[ 988.454119] smp_call_function_single+0x158/0x1b8
[ 988.458866] cti_enable+0xb4/0xf8 [coresight_cti]
[ 988.463618] coresight_control_assoc_ectdev+0x6c/0x128 [coresight]
[ 988.469855] coresight_enable+0x1f0/0x364 [coresight]
[ 988.474957] enable_source_store+0x5c/0x9c [coresight]
[ 988.480140] dev_attr_store+0x14/0x28
[ 988.483839] sysfs_kf_write+0x38/0x4c
[ 988.487532] kernfs_fop_write+0x1c0/0x2b0
[ 988.491585] vfs_write+0xfc/0x300
[ 988.494931] ksys_write+0x78/0xe0
[ 988.498283] __arm64_sys_write+0x18/0x20
[ 988.502240] el0_svc_common+0x98/0x160
[ 988.506024] do_el0_svc+0x78/0x80
[ 988.509377] el0_sync_handler+0xd4/0x270
[ 988.513337] el0_sync+0x164/0x180
This change write CTI registers directly in cti_enable_hw().
Config->hw_powered has been checked to be true with spinlock holded.
CTI is powered and can be programmed until spinlock is released.
Fixes:
|
||
|---|---|---|
| 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.