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Kirill Smelkov 3975b097e5 *: convert stream-like files -> stream_open, even if they use noop_llseek
This patch continues 10dce8af34 (fs: stream_open - opener for
stream-like files so that read and write can run simultaneously without
deadlock) and c5bf68fe0c (*: convert stream-like files from
nonseekable_open -> stream_open) and teaches steam_open.cocci to
consider files as being stream-like not only if they have
.llseek=no_llseek, but also if they have .llseek=noop_llseek.

This is safe to do: the comment about noop_llseek says

	This is an implementation of ->llseek useable for the rare special case when
	userspace expects the seek to succeed but the (device) file is actually not
	able to perform the seek. In this case you use noop_llseek() instead of
	falling back to the default implementation of ->llseek.

and in general noop_llseek was massively added to drivers in 6038f373a3
(llseek: automatically add .llseek fop) when changing default for NULL .llseek
from NOP to no_llseek with the idea to avoid breaking compatibility, if
maybe some user-space program was using lseek on a device without caring
about the result, but caring if it was an error or not.

Amended semantic patch produces two changes when applied tree-wide:

        drivers/hid/hid-sensor-custom.c:690:8-24: WARNING: hid_sensor_custom_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
        drivers/input/mousedev.c:564:1-17: ERROR: mousedev_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.

Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jan Blunck <jblunck@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
2019-07-14 16:09:19 +03:00
arch A few more MIPS fixes: 2019-07-06 10:32:12 -07:00
block blk-mq: fix up placement of debugfs directory of queue files 2019-07-06 10:07:38 -06:00
certs treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-05 13:31:19 +09:00
Documentation dt-bindings: riscv: resolve 'make dt_binding_check' warnings 2019-06-26 10:28:53 -07:00
drivers *: convert stream-like files -> stream_open, even if they use noop_llseek 2019-07-14 16:09:19 +03:00
fs Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-06 09:53:08 -07:00
include Revert "mm: page cache: store only head pages in i_pages" 2019-07-05 19:55:18 -07:00
init initramfs: fix populate_initrd_image() section mismatch 2019-06-29 16:43:45 +08:00
ipc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
kernel ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME 2019-07-05 02:00:41 +09:00
lib Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-05 13:31:19 +09:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Revert "mm: page cache: store only head pages in i_pages" 2019-07-05 19:55:18 -07:00
net Two more quick bugfixes for nfsd, fixing a regression causing mount 2019-07-05 19:00:37 -07:00
samples samples: make pidfd-metadata fail gracefully on older kernels 2019-06-24 15:55:50 +02:00
scripts *: convert stream-like files -> stream_open, even if they use noop_llseek 2019-07-14 16:09:19 +03:00
security SPDX update for 5.2-rc6 2019-06-21 09:58:42 -07:00
sound sound fixes for 5.2 2019-07-05 02:03:50 +09:00
tools KVM: nVMX: Change KVM_STATE_NESTED_EVMCS to signal vmcs12 is copied from eVMCS 2019-07-02 19:02:45 +02:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt SPDX update for 5.2-rc6 2019-06-21 09:58:42 -07:00
.clang-format Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-04-17 11:26:25 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore .gitignore: exclude .get_maintainer.ignore and .gitattributes 2019-05-18 11:49:54 +09:00
.mailmap MAINTAINERS: Update my email address 2019-06-18 14:37:27 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Farewell Martin Schwidefsky 2019-05-31 10:14:11 +02:00
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS A few more MIPS fixes: 2019-07-06 10:32:12 -07:00
Makefile Linux 5.2 2019-07-07 15:41:56 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.