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Takashi Iwai d8e9b2b909 drm/i915/gvt: Fix superfluous newline in GVT_DISPLAY_READY env var
send_display_send_uevent() sends two environment variable, and the
first one GVT_DISPLAY_READY is set including a new line at the end of
the string; that is obviously superfluous and wrong -- at least, it
*looks* so when you only read the code.

However, it doesn't appear in the actual output by a (supposedly
unexpected) trick.  The code uses snprintf() and truncates the string
in size 20 bytes.  This makes the string as GVT_DISPLAY_READY=0 or
...=1 including the trailing NUL-letter.  That is, the '\n' found in
the format string is always cut off as a result.

Although the code gives the correct result, it is confusing.  This
patch addresses it, just removing the superfluous '\n' from the format
string for avoiding further confusion.  If the argument "ready" were
not a  bool, the size 20 should be corrected as well.  But it's a
bool, so we can leave the magic number 20 as is for now.

FWIW, the bug was spotted by a new GCC7 warning:
  drivers/gpu/drm/i915/gvt/handlers.c: In function 'pvinfo_mmio_write':
  drivers/gpu/drm/i915/gvt/handlers.c:1042:34: error: 'snprintf' output truncated before the last format character [-Werror=format-truncation=]
    snprintf(display_ready_str, 20, "GVT_DISPLAY_READY=%d\n", ready);
                                    ^~~~~~~~~~~~~~~~~~~~~~~~
  drivers/gpu/drm/i915/gvt/handlers.c:1042:2: note: 'snprintf' output 21 bytes into a destination of size 20
    snprintf(display_ready_str, 20, "GVT_DISPLAY_READY=%d\n", ready);
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 04d348ae3f ("drm/i915/gvt: vGPU display virtualization")
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1025903
Reported-by: Richard Biener <rguenther@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-02-23 17:32:14 +08:00
arch Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next 2017-01-27 11:00:42 +10:00
block blk-mq: Remove unused variable 2017-01-18 15:14:15 -07:00
certs certs: Add a secondary system keyring that can be added to dynamically 2016-04-11 22:48:09 +01:00
crypto crypto: testmgr - Use heap buffer for acomp test input 2016-12-27 17:32:11 +08:00
Documentation Merge tag 'drm-misc-next-2017-01-30' of git://anongit.freedesktop.org/git/drm-misc into drm-next 2017-02-01 08:31:09 +10:00
drivers drm/i915/gvt: Fix superfluous newline in GVT_DISPLAY_READY env var 2017-02-23 17:32:14 +08:00
firmware WHENCE: use https://linuxtv.org for LinuxTV URLs 2015-12-04 10:35:11 -02:00
fs romfs: use different way to generate fsid for BLOCK or MTD 2017-01-24 16:26:14 -08:00
include Merge branch 'drm-next-4.11' of git://people.freedesktop.org/~agd5f/linux into drm-next 2017-02-01 08:39:35 +10:00
init cgroup: move CONFIG_SOCK_CGROUP_DATA to init/Kconfig 2017-01-11 09:47:10 -05:00
ipc ipc/sem.c: fix incorrect sem_lock pairing 2017-01-10 18:31:55 -08:00
kernel sysctl: fix proc_doulongvec_ms_jiffies_minmax() 2017-01-26 09:21:24 -08:00
lib Merge tag 'drm-misc-next-2017-01-30' of git://anongit.freedesktop.org/git/drm-misc into drm-next 2017-02-01 08:31:09 +10:00
mm mm, page_alloc: fix premature OOM when racing with cpuset mems update 2017-01-24 16:26:14 -08:00
net Three filesystem endianness fixes (one goes back to the 2.6 era, all 2017-01-20 12:15:48 -08:00
samples Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-01-15 11:37:43 -08:00
scripts gcc-plugins: update gcc-common.h for gcc-7 2017-01-03 12:08:59 -08:00
security Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
sound Merge tag 'drm-intel-next-2017-01-23' of git://anongit.freedesktop.org/git/drm-intel into drm-next 2017-01-27 12:08:32 +10:00
tools Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next 2017-01-27 11:00:42 +10:00
usr kbuild: initramfs cleanup, set target from Kconfig 2017-01-05 09:40:16 -08:00
virt KVM/ARM updates for 4.10-rc4 2017-01-17 15:04:59 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-08-02 16:48:52 -04:00
.mailmap mailmap: add codeaurora.org names for nameless email commits 2017-01-10 18:31:55 -08:00
COPYING
CREDITS CREDITS: Remove outdated address information 2016-12-21 15:21:29 -08:00
Kbuild scripts/gdb: provide linux constants 2016-05-23 17:04:14 -07:00
Kconfig
MAINTAINERS Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next 2017-01-27 11:00:42 +10:00
Makefile Linux 4.10-rc5 2017-01-22 12:54:15 -08:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

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.