commit 10dce8af34 upstream.
[ while porting to 3.16 xenbus conflict was trivially resolved in a way
that actually fixes /proc/xen/xenbus deadlock introduced in 3.14,
because original upstream commit 581d21a2d0 to fix xenbus deadlock
was not included into 3.16 . ]
Commit 9c225f2655 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.
This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d0 ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.
The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.
However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655 -
is doing so irregardless of whether a file is seekable or not.
See
https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/https://lwn.net/Articles/180387https://lwn.net/Articles/180396
for historic context.
The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:
kernel/power/user.c snapshot_read
fs/debugfs/file.c u32_array_read
fs/fuse/control.c fuse_conn_waiting_read + ...
drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read
arch/s390/hypfs/inode.c hypfs_read_iter
...
Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -> deadlock.
Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):
drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()
In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.
FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f7 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:
See
https://github.com/libfuse/osspdhttps://lwn.net/Articles/30844514a9cff0/osspd.c (L1406)14a9cff0/osspd.c (L1438-L1477)14a9cff0/osspd.c (L1479-L1510)
Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216
I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:
f13aa600/wcfs/wcfs.go (L88-169)
Let's fix this regression. The plan is:
1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS -
doing so would break many in-kernel nonseekable_open users which
actually use ppos in read/write handlers.
2. Add stream_open() to kernel to open stream-like non-seekable file
descriptors. Read and write on such file descriptors would never use
nor change ppos. And with that property on stream-like files read and
write will be running without taking f_pos lock - i.e. read and write
could be running simultaneously.
3. With semantic patch search and convert to stream_open all in-kernel
nonseekable_open users for which read and write actually do not
depend on ppos and where there is no other methods in file_operations
which assume @offset access.
4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
steam_open if that bit is present in filesystem open reply.
It was tempting to change fs/fuse/ open handler to use stream_open
instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and
write handlers
https://codesearch.debian.net/search?q=-%3Enonseekable+%3Dhttps://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481
so if we would do such a change it will break a real user.
5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
from v3.14+ (the kernel where 9c225f2655 first appeared).
This will allow to patch OSSPD and other FUSE filesystems that
provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
in their open handler and this way avoid the deadlock on all kernel
versions. This should work because fs/fuse/ ignores unknown open
flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel
that is not aware of FOPEN_STREAM will be < v3.14 where just
FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
write deadlock.
This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.
Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.
The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ backport to 3.16: actually fixed deadlock on /proc/xen/xenbus as 581d21a2d0 was not backported to 3.16 ]
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 1b669e713f upstream.
& is no longer allowed in column 0, since Coccinelle 1.0.4.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This semantic patch looks for variables that are initialized with a
constant, are never updated, and are only used as parameter of return.
Return the constant instead of using a variable.
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Failure to terminate an of_device_id table can lead to confusing
failures depending on where the compiler places the array. Add a
check to make sure these tables are terminated. Thanks to Mitchel
Humpherys for coming up with the pattern initially.
Cc: Mitchel Humpherys <mitchelh@codeaurora.org>
Cc: Gilles Muller <Gilles.Muller@lip6.fr>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
PTR_RET is deprecated. Do not recommend its usage anymore.
Use PTR_ERR_OR_ZERO instead.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
The Coccinelle script scripts/coccinelle/misc/memcpy-assign.cocci look
for opportunities to replace a call to memcpy by a struct assignment.
This patch removes memcpy-assign.cocci as it is not clear that this
convention has an impact on the generated code.
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
As indicated by Sekhar in [1], there seems to be a tendency to use
IS_ERR_VALUE to check the error result for pm_runtime_* functions which
make no sense considering commit c48cd65 (ARM: OMAP: use consistent
error checking) - the error values can either be < 0 for error OR
0, 1 in cases where we have success.
So, setup a coccinelle script to help identify the same.
[1] http://marc.info/?t=138472678100003&r=1&w=2
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Reported-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Use of this function is discouraged in favour of
devm_ioremap_resource(). Don't advertise it.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Pull misc kbuild updates from Michal Marek:
"In the kbuild misc branch, I have:
- make rpm-pkg updates, most importantly the rpm package now calls
/sbin/installkernel
- make deb-pkg: debuginfo split, correct kernel image path for
parisc, mips and powerpc and a couple more minor fixes
- New coccinelle check"
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scripts/checkkconfigsymbols.sh: replace echo -e with printf
Provide version number for Debian firmware package
coccinelle: replace 0/1 with false/true in functions returning bool
deb-pkg: add a hook argument to match debian hooks parameters
deb-pkg: fix installed image path on parisc, mips and powerpc
deb-pkg: split debug symbols in their own package
deb-pkg: use KCONFIG_CONFIG instead of .config file directly
rpm-pkg: add generation of kernel-devel
rpm-pkg: install firmware files in kernel relative directory
rpm-pkg: add %post section to create initramfs and grub hooks
This semantic patch replaces "return {0,1};" with "return
{false,true};" in functions returning bool.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
spatch has changed its option scheme.
E.g., --no_show_diff is now --no-show-diff
This patch updates:
- scripts/coccicheck
- Semantic patches under scripts/coccinelle/
Signed-off-by: Nicolas Palix <nicolas.palix@imag.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Created coccinelle script for reporting missing pci_free_consistent() calls.
Signed-off-by: Petr Strnad <strnape1@fel.cvut.cz>
Signed-off-by: Nicolas Palix <nicolas.palix@imag.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
The argument to kfree should not be the address of a structure field.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Pull misc non-critical kbuild changes from Michal Marek:
- Fix for make TAGS
- Fix for make rpm
- Some new coccinelle semantic patches
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scripts/coccinelle: find constant additions that could be bit ors
coccicheck: Allow to show the executed command line
coccicheck: Allow the user to give a V= (verbose) argument
scripts/coccinelle/misc/memcpy-assign.cocci: Replace memcpy with struct assignment
kbuild: clear KBUILD_SRC when calling 'make' in RPM spec
scripts/coccinelle/misc/semicolon.cocci: Add unneeded semicolon test
scripts/tags.sh: Fix regex syntax for etags
Semantic patch (http://coccinelle.lip6.fr/) to check for constants that are
added but are used elsewhere as bitmasks.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
There are error-prone memcpy() that can be replaced by struct
assignment that are type-safe and much easier to read. This semantic
patch looks for memcpy() that can be replaced by struct assignment.
Inspired by patches sent by Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
This semantic patch looks for semicolons that can be removed without
changing the semantics of the code. The confidence is moderate
because there are some false positives on cases like:
b/drivers/mmc/host/cb710-mmc.c:589
break;
case MMC_POWER_UP:
default:
- /* ignore */;
}
There are 37 patches accepted reported by this semantic patch and
more than 300 fixes to be applied.
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
The devm_request_and_ioremap() function is very useful and helps avoid a
whole lot of boilerplate. However, one issue that keeps popping up is
its lack of a specific error code to determine which of the steps that
it performs failed. Furthermore, while the function gives an example and
suggests what error code to return on failure, a wide variety of error
codes are used throughout the tree.
In an attempt to fix these problems, this patch adds a new function that
drivers can transition to. The devm_ioremap_resource() returns a pointer
to the remapped I/O memory on success or an ERR_PTR() encoded error code
on failure. Callers can check for failure using IS_ERR() and determine
its cause by extracting the error code using PTR_ERR().
devm_request_and_ioremap() is implemented as a wrapper around the new
API and return NULL on failure as before. This ensures that backwards
compatibility is maintained until all users have been converted to the
new API, at which point the old devm_request_and_ioremap() function
should be removed.
A semantic patch is included which can be used to convert from the old
devm_request_and_ioremap() API to the new devm_ioremap_resource() API.
Some non-trivial cases may require manual intervention, though.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull kbuild misc changes from Michal Marek:
"This is the non-critical part of kbuild
- scripts/kernel-doc requires a "Return:" section for non-void
functions
- ARCH=arm SUBARCH=... support for make tags
- COMPILED_SOURCE=1 support for make tags (only indexes .c files for
which a .o exists)
- New coccinelle check
- Option parsing fix for scripts/config"
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scripts/config: Fix wrong "shift" for --keep-case
scripts/tags.sh: Support compiled source
scripts/tags.sh: Support subarch for ARM
scripts/coccinelle/misc/warn.cocci: use WARN
scripts/kernel-doc: check that non-void fcts describe their return value
Kernel-doc: Convention: Use a "Return" section to describe return values
Ensure that calls to d_find_alias() have a corresponding dput().
Signed-off-by: Cyril Roelandt <tipecaml@gmail.com>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Gilles Muller <Gilles.Muller@lip6.fr>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use WARN(1,...) rather than printk followed by WARN(1).
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Pull kbuild misc changes from Michal Marek:
"In the non-critical part of kbuild, I have
- Some make coccicheck improvements and two new tests
- Support for a cleaner html output in scripts/kernel-doc, named
html5 (no, it does not play videos, yet)
BTW, Randy wants to route further kernel-doc patches through the
kbuild tree."
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
Update SmPL/Coccinelle section of MAINTAINERS
coccicheck: Add the rep+ctxt mode
scripts/coccinelle/tests/odd_ptr_err.cocci: semantic patch for IS_ERR/PTR_ERR inconsistency
scripts/tags.sh: Add magic for pci access functions
scripts/coccinelle: ptr_ret: Add ternary operator version
scripts/kernel-doc: drop maintainer
scripts/kernel-doc: added support for html5
Pull the trivial tree from Jiri Kosina:
"Tiny usual fixes all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
doc: fix old config name of kprobetrace
fs/fs-writeback.c: cleanup riteback_sb_inodes kerneldoc
btrfs: fix the commment for the action flags in delayed-ref.h
btrfs: fix trivial typo for the comment of BTRFS_FREE_INO_OBJECTID
vfs: fix kerneldoc for generic_fh_to_parent()
treewide: fix comment/printk/variable typos
ipr: fix small coding style issues
doc: fix broken utf8 encoding
nfs: comment fix
platform/x86: fix asus_laptop.wled_type module parameter
mfd: printk/comment fixes
doc: getdelays.c: remember to close() socket on error in create_nl_socket()
doc: aliasing-test: close fd on write error
mmc: fix comment typos
dma: fix comments
spi: fix comment/printk typos in spi
Coccinelle: fix typo in memdup_user.cocci
tmiofb: missing NULL pointer checks
tools: perf: Fix typo in tools/perf
tools/testing: fix comment / output typos
...
Add a ternary operator version of the open-coded PTR_RET().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
If list_for_each_entry, etc complete a traversal of the list, the iterator
variable ends up pointing to an address at an offset from the list head,
and not a meaningful structure. Thus this value should not be used after
the end of the iterator.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Since commit 1c6c69525b ("genirq: Reject bogus threaded irq requests") threaded
IRQs without a primary handler need to be requested with IRQF_ONESHOT, otherwise
the request will fail. This semantic patch will help to statically identify
(and fix) such cases.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Pull misc kbuild changes from Michal Marek:
"The non-critical part of kbuild for 3.5 includes
- two new coccinelle checks
- fix for make deb-pkg to include generated headers in arch/*/include
I have more make-deb-pkg fixes in the backlog, but these will likely
have to wait for 3.6."
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
builddeb: include autogenerated header files
scripts/coccinelle: sizeof of pointer
scripts/coccinelle: address test is always true
Merge batch of fixes from Andrew Morton:
"The simple_open() cleanup was held back while I wanted for laggards to
merge things.
I still need to send a few checkpoint/restore patches. I've been
wobbly about merging them because I'm wobbly about the overall
prospects for success of the project. But after speaking with Pavel
at the LSF conference, it sounds like they're further toward
completion than I feared - apparently davem is at the "has stopped
complaining" stage regarding the net changes. So I need to go back
and re-review those patchs and their (lengthy) discussion."
* emailed from Andrew Morton <akpm@linux-foundation.org>: (16 patches)
memcg swap: use mem_cgroup_uncharge_swap fix
backlight: add driver for DA9052/53 PMIC v1
C6X: use set_current_blocked() and block_sigmask()
MAINTAINERS: add entry for sparse checker
MAINTAINERS: fix REMOTEPROC F: typo
alpha: use set_current_blocked() and block_sigmask()
simple_open: automatically convert to simple_open()
scripts/coccinelle/api/simple_open.cocci: semantic patch for simple_open()
libfs: add simple_open()
hugetlbfs: remove unregister_filesystem() when initializing module
drivers/rtc/rtc-88pm860x.c: fix rtc irq enable callback
fs/xattr.c:setxattr(): improve handling of allocation failures
fs/xattr.c:listxattr(): fall back to vmalloc() if kmalloc() failed
fs/xattr.c: suppress page allocation failure warnings from sys_listxattr()
sysrq: use SEND_SIG_FORCED instead of force_sig()
proc: fix mount -t proc -o AAA
Find instances of an open-coded simple_open() and replace them with
calls to simple_open().
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reported-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch ensures that all semantic patches in the scripts/coccinelle
directory provide the report option. Report messages that include line
numbers now have the line number preceded by "line" for easier subsequent
processing.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
devm_ functions allocate memory that is to remain allocated until the
device is detached. This patch checks for freeing of such memory using
standard memory freeing functions.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
devm_ functions allocate memory that is to remain allocated until the
device is detached. This patch checks for opportunities for using the
function devm_request_and_ioremap.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
For doubleinit.cocci, Coccinelle 0.2.4 requires a comma after ... in a
field list. Coccinelle also now behaves gracefully when a definition is
provided for a virtual that doesn't exist, so there is no need for the
semantic patch code to check for this case.
Updated the documentation to reflect the fact that the best results will
now be obtained with Coccinelle version 0.2.4 or later.
Signed-off-by: Julia Lawall <julia@diku.dk>
Use new comment format to separate proposed commit message
and information about generated false positives
Signed-off-by: Nicolas Palix <npalix.work@gmail.com>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Find confusingly indented code in or after an if. An if branch should
be indented. The code following an if should not be indented.
Sometimes, code after an if that is indented is actually intended to be
part of the if branch.
This has a high rate of false positives, because Coccinelle's column
calculation does not distinguish between spaces and tabs, so code that
is not visually aligned may be considered to be in the same column.
Signed-off-by: Nicolas Palix <npalix@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Find duplicate field initializations. This has a high rate of false
positives due to #ifdefs, which Coccinelle is not aware of in a structure
initialization.
Signed-off-by: Nicolas Palix <npalix@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
alloc contains various semantic patches related
to the allocation APIs
Signed-off-by: Nicolas Palix <npalix@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
