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.
Juergen Gross
authored
In case a user process using xenbus has open transactions and is killed e.g. via ctrl-C the following cleanup of the allocated resources might result in a deadlock due to trying to end a transaction in the xenbus worker thread: [ 2551.474706] INFO: task xenbus:37 blocked for more than 120 seconds. [ 2551.492215] Tainted: P OE 5.0.0-29-generic #5 [ 2551.510263] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 2551.528585] xenbus D 0 37 2 0x80000080 [ 2551.528590] Call Trace: [ 2551.528603] __schedule+0x2c0/0x870 [ 2551.528606] ? _cond_resched+0x19/0x40 [ 2551.528632] schedule+0x2c/0x70 [ 2551.528637] xs_talkv+0x1ec/0x2b0 [ 2551.528642] ? wait_woken+0x80/0x80 [ 2551.528645] xs_single+0x53/0x80 [ 2551.528648] xenbus_transaction_end+0x3b/0x70 [ 2551.528651] xenbus_file_free+0x5a/0x160 [ 2551.528654] xenbus_dev_queue_reply+0xc4/0x220 [ 2551.528657] xenbus_thread+0x7de/0x880 [ 2551.528660] ? wait_woken+0x80/0x80 [ 2551.528665] kthread+0x121/0x140 [ 2551.528667] ? xb_read+0x1d0/0x1d0 [ 2551.528670] ? kthread_park+0x90/0x90 [ 2551.528673] ret_from_fork+0x35/0x40 Fix this by doing the cleanup via a workqueue instead. Reported-by:James Dingwall <james@dingwall.me.uk> Fixes: fd8aa909 ("xen: optimize xenbus driver for multiple concurrent xenstore accesses") Cc: <stable@vger.kernel.org> # 4.11 Signed-off-by:
Juergen Gross <jgross@suse.com> Reviewed-by:
Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by:
| Name | Last commit | Last update |
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| 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 |