A lot of stack is used in recursive printks with %pV.
Using multiple levels of %pV (a logging function with %pV
that calls another logging function with %pV) can consume
more stack than necessary.
Avoid excessive stack use by not calling dev_printk from
netdev_printk and dynamic_netdev_dbg. Duplicate the logic
and form of dev_printk instead.
Make __netdev_printk static.
Remove EXPORT_SYMBOL(__netdev_printk)
Whitespace and brace style neatening.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c4e00daaa9
("driver-core: extend dev_printk() to pass structured data")
changed __dev_printk and broke dynamic-debug's ability to control the
dynamic prefix of dev_dbg(dev,..).
commit af7f2158fd
("drivers-core: make structured logging play nice with dynamic-debug")
made a minimal correction.
The current dynamic debug code uses up to 3 recursion levels via %pV.
This can consume quite a bit of stack. Directly call printk_emit to
reduce the recursion depth.
These changes include:
dev_dbg:
o Create and use function create_syslog_header to format the syslog
header for printk_emit uses.
o Call create_syslog_header and neaten __dev_printk
o Make __dev_printk static not global
o Remove include header declaration of __dev_printk
o Remove now unused EXPORT_SYMBOL() of __dev_printk
o Whitespace neatening
dynamic_dev_dbg:
o Remove KERN_DEBUG from dynamic_emit_prefix
o Call create_syslog_header and printk_emit
o Whitespace neatening
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds Makefile and Kconfig files required for building an
AArch64 kernel.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
When pkcs_1_v1_5_decode_emsa() returns without error and hash sizes do
not match, hash comparision is not done and digsig_verify_rsa() returns
no error. This is a bug and this patch fixes it.
The bug was introduced in v3.3 by commit b35e286a64 ("lib/digsig:
pkcs_1_v1_5_decode_emsa cleanup").
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel's version number is used as decimal in the bcdDevice field of
the RH descriptor. For kernel version v3.12 we would see 3.0c in lsusb.
I am not sure how important it is to stick with bcd values since this is
this way since we started git history and nobody complained (however back
then we reported only 2.6).
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch defines netlink_kernel_create as a wrapper function of
__netlink_kernel_create to hide the struct module *me parameter
(which seems to be THIS_MODULE in all existing netlink subsystems).
Suggested by David S. Miller.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace netlink_set_nonroot by one new field `flags' in
struct netlink_kernel_cfg that is passed to netlink_kernel_create.
This patch also renames NL_NONROOT_* to NL_CFG_F_NONROOT_* since
now the flags field in nl_table is generic (so we can add more
flags if needed in the future).
Also adjust all callers in the net-next tree to use these flags
instead of netlink_set_nonroot.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This enables the caller to initialize swiotlb with its own iotlb
memory late in the bootup.
See git commit eb605a5754
"swiotlb: add swiotlb_tbl_map_single library function" which will
explain the full details of what it can be used for.
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
[v1: Fold in smatch warning]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We are seeing a lot of sg_alloc_table allocation failures using the new
drm prime infrastructure. We isolated the cause to code in
__sg_alloc_table that was re-writing the gfp_flags.
There is a comment in the code that suggest that there is an assumption
about the allocation coming from a memory pool. This was likely true
when sg lists were primarily used for disk I/O.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Cong Wang <amwang@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Rob Clark <rob.clark@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Sonny Rao <sonnyrao@chromium.org>
Cc: Olof Johansson <olofj@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This provides the ability to inject artifical errors to pSeries reconfig
notifier chain callbacks. It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/pSeries-reconfig
If the notifier call chain should be failed with some events
notified, write the error code to "actions/<notifier event>/error".
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This provides the ability to inject artifical errors to memory hotplug
notifier chain callbacks. It is controlled through debugfs interface
under /sys/kernel/debug/notifier-error-inject/memory
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example: Inject memory hotplug offline error (-12 == -ENOMEM)
# cd /sys/kernel/debug/notifier-error-inject/memory
# echo -12 > actions/MEM_GOING_OFFLINE/error
# echo offline > /sys/devices/system/memory/memoryXXX/state
bash: echo: write error: Cannot allocate memory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This provides the ability to inject artifical errors to PM notifier chain
callbacks. It is controlled through debugfs interface under
/sys/kernel/debug/notifier-error-inject/pm
Each of the files in "error" directory represents an event which can be
failed and contains the error code. If the notifier call chain should be
failed with some events notified, write the error code to the files.
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example: Inject PM suspend error (-12 = -ENOMEM)
# cd /sys/kernel/debug/notifier-error-inject/pm
# echo -12 > actions/PM_SUSPEND_PREPARE/error
# echo mem > /sys/power/state
bash: echo: write error: Cannot allocate memory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rewrite existing cpu-notifier-error-inject module to use debugfs based new
framework.
This change removes cpu_up_prepare_error and cpu_down_prepare_error module
parameters which were used to specify error code to be injected. We could
keep these module parameters for backward compatibility by module_param_cb
but it seems overkill for this module.
This provides the ability to inject artifical errors to CPU notifier chain
callbacks. It is controlled through debugfs interface under
/sys/kernel/debug/notifier-error-inject/cpu
If the notifier call chain should be failed with some events notified,
write the error code to "actions/<notifier event>/error".
Example1: inject CPU offline error (-1 == -EPERM)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -1 > actions/CPU_DOWN_PREPARE/error
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permitted
Example2: inject CPU online error (-2 == -ENOENT)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -2 > actions/CPU_UP_PREPARE/error
# echo 1 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: No such file or directory
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset provides kernel modules that can be used to test the error
handling of notifier call chain failures by injecting artifical errors to
the following notifier chain callbacks.
* CPU notifier
* PM notifier
* memory hotplug notifier
* powerpc pSeries reconfig notifier
Example: Inject CPU offline error (-1 == -EPERM)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -1 > actions/CPU_DOWN_PREPARE/error
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permitted
The patchset also adds cpu and memory hotplug tests to
tools/testing/selftests These tests first do simple online and offline
test and then do fault injection tests if notifier error injection
module is available.
This patch:
The notifier error injection provides the ability to inject artifical
errors to specified notifier chain callbacks. It is useful to test the
error handling of notifier call chain failures.
This adds common basic functions to define which type of events can be
fail and to initialize the debugfs interface to control what error code
should be returned and which event should be failed.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Variables t4, t5, t6 and t7 are only used when CRC_LE_BITS != 32. Fix
the following compilation warnings:
lib/crc32.c: In function 'crc32_body':
lib/crc32.c:77:55: warning: unused variable 't7'
lib/crc32.c:77:41: warning: unused variable 't6'
lib/crc32.c:77:27: warning: unused variable 't5'
lib/crc32.c:77:13: warning: unused variable 't4'
Signed-off-by: Thiago Rafael Becker <trbecker@trbecker.org>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If there are two spinlocks embedded in a structure that kallsyms knows
about and one of the spinlocks locks up we will print the name of the
containing structure instead of the address of the lock. This is quite
bad, so let's use %pS instead of %ps so we get an offset in addition to
the symbol so we can determine which particular lock is having problems.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE and use this instead
of the multitude of #if defined() checks in atomic64_test.c
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memweight() is the function that counts the total number of bits set in
memory area. Unlike bitmap_weight(), memweight() takes pointer and size
in bytes to specify a memory area which does not need to be aligned to
long-word boundary.
[akpm@linux-foundation.org: rename `w' to `ret']
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Anders Larsen <al@alarsen.net>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are many places in the kernel where the drivers print small buffers
as a hex string. This patch adds a support of the variable width buffer
to print it as a hex string with a delimiter. The idea came from Pavel
Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/
Sample output of
pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]);
could be look like this:
[ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e
[ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55
[ 0.757602] buf[17:5] ac:16:d5:2c:ef
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using ALT+SysRq+Q all the pointers are replaced with "pK-error" like
this:
[23153.208033] .base: pK-error
with echo h > /proc/sysrq-trigger it works:
[23107.776363] .base: ffff88023e60d540
The intent behind this behavior was to return "pK-error" in cases where
the %pK format specifier was used in interrupt context, because the
CAP_SYSLOG check wouldn't be meaningful. Clearly this should only apply
when kptr_restrict is actually enabled though.
Reported-by: Stevie Trujillo <stevie.trujillo@gmail.com>
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bluetooth uses mostly LE byte order which is reversed for visual
interpretation. Currently in Bluetooth in use unsafe batostr function.
This is a slightly modified version of Joe's patch (sent Sat, Dec 4,
2010).
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Cc: Joe Perches <joe@perches.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds a new constructor for an sg table. The table is constructed
from an array of struct pages. All contiguous chunks of the pages are merged
into a single sg nodes. A user may provide an offset and a size of a buffer if
the buffer is not page-aligned.
The function is dedicated for DMABUF exporters which often perform conversion
from an page array to a scatterlist. Moreover the scatterlist should be
squashed in order to save memory and to speed-up the process of DMA mapping
using dma_map_sg.
The code is based on the patch 'v4l: vb2-dma-contig: add support for
scatterlist in userptr mode' and hints from Laurent Pinchart.
Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
CC: Andrew Morton <akpm@linux-foundation.org>
libfdt is part of the device tree support in scripts/dtc/libfdt. For
some platforms that use the Device Tree, we want to be able to edit
the flattened device tree form.
We don't want to burden kernel builds that do not require it, so we
gate compilation of libfdt files with CONFIG_LIBFDT. So if it is
needed, you need to do this in your Kconfig:
select LIBFDT
And in the Makefile of the code using libfdt something like:
ccflags-y := -I$(src)/../../../scripts/dtc/libfdt
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The stack_not_used() function in <linux/sched.h> assumes that stacks
grow downwards. This is not true on IA64 or PARISC, so this function
would walk off in the wrong direction and into the weeds.
Found on IA64 because of a compilation failure with recursive dependencies
on IA64_TASKSIZE and IA64_THREAD_INFO_SIZE.
Fixing the code is possible, but should be combined with other
infrastructure additions to set up the "canary" at the end of the stack.
Reported-by: Fengguang Wu <fengguang.wu@intel.com> (failed allmodconfig build)
Signed-off-by: Tony Luck <tony.luck@intel.com>
Although the C language allows you to break strings across lines, doing
this makes it hard for people to find the Linux kernel code corresponding
to a given console message. This commit therefore fixes broken strings
throughout RCU's source code.
Suggested-by: Josh Triplett <josh@joshtriplett.org>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Even though it has "bool" in the name, you have pass a u32 pointer to
debugfs_create_bool(). Otherwise you get memory corruption in
write_file_bool(). Fortunately in this case the corruption happens in
an alignment hole between variables so it doesn't cause any problems.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch adds the following structure:
struct netlink_kernel_cfg {
unsigned int groups;
void (*input)(struct sk_buff *skb);
struct mutex *cb_mutex;
};
That can be passed to netlink_kernel_create to set optional configurations
for netlink kernel sockets.
I've populated this structure by looking for NULL and zero parameters at the
existing code. The remaining parameters that always need to be set are still
left in the original interface.
That includes optional parameters for the netlink socket creation. This allows
easy extensibility of this interface in the future.
This patch also adapts all callers to use this new interface.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
After enabling CONFIG_FAILSLAB I noticed random32 in profiles even if slub
fault injection wasn't enabled at runtime.
should_fail forces a comparison against random32() even if probability is
0:
if (attr->probability <= random32() % 100)
return false;
Add a check up front for probability == 0 and avoid all of the more
complicated checks.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When percpu counter function in fprop_new_period() is interrupted by an
interrupt while holding counter lock, it can cause deadlock when the
interrupt wants to take the lock as well. Fix the problem by disabling
interrupts when calling percpu counter functions.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Implement code computing proportions of events of different type (like code in
lib/proportions.c) but allowing periods to have different lengths. This allows
us to have aging periods of fixed wallclock time which gives better proportion
estimates given the hugely varying throughput of different devices - previous
measuring of aging period by number of events has the problem that a reasonable
period length for a system with low-end USB stick is not a reasonable period
length for a system with high-end storage array resulting either in too slow
proportion updates or too fluctuating proportion updates.
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Storing NULL values in the btree is illegal and can lead to memory
corruption and possible other fun as well. Catch it on insert, instead
of waiting for the inevitable.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The memory the parameter __key points to is used as an iterator in
btree_get_prev(), so if we save off a bkey() pointer in retry_key and
then assign that to __key, we'll end up corrupting the btree internals
when we do eg
longcpy(__key, bkey(geo, node, i), geo->keylen);
to return the key value. What we should do instead is use longcpy() to
copy the key value that retry_key points to __key.
This can cause a btree to get corrupted by seemingly read-only
operations such as btree_for_each_safe.
[akpm@linux-foundation.org: avoid the double longcpy()]
Signed-off-by: Roland Dreier <roland@purestorage.com>
Acked-by: Joern Engel <joern@logfs.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On an over-committed KVM system we got a:
"BUG: spinlock lockup on CPU#2, swapper/2/0"
message on the heavily contended virtio blk spinlock.
While we might want to reconsider the locking of virtio-blk
(lock is held while switching to the host) this patch tries to
make the message clearer: the lockup is only suspected.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338283124-7063-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes bug in macro radix_tree_for_each_contig().
If radix_tree_next_slot() sees NULL in next slot it returns NULL, but following
radix_tree_next_chunk() switches iterating into next chunk. As result iterating
becomes non-contiguous and breaks vfs "splice" and all its users.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reported-and-bisected-by: Hans de Bruin <jmdebruin@xmsnet.nl>
Reported-and-bisected-by: Ondrej Zary <linux@rainbow-software.org>
Reported-bisected-and-tested-by: Toralf Förster <toralf.foerster@gmx.de>
Link: https://lkml.org/lkml/2012/6/5/64
Cc: stable <stable@vger.kernel.org> # 3.4.x
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Previous code was using optimizations which were developed to work well
even on narrow-word CPUs (by today's standards). But Linux runs only on
32-bit and wider CPUs. We can use that.
First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly
divide by 10 much larger numbers, and thus we can print groups of 9 digits
instead of groups of 5 digits.
Next: there are two algorithms to print larger numbers. One is generic:
divide by 1000000000 and repeatedly print groups of (up to) 9 digits.
It's conceptually simple, but requires an (unsigned long long) /
1000000000 division.
Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
manipulates them cleverly and generates groups of 4 decimal digits. It so
happens that it does NOT require long long division.
If long is > 32 bits, division of 64-bit values is relatively easy, and we
will use the first algorithm. If long long is > 64 bits (strange
architecture with VERY large long long), second algorithm can't be used,
and we again use the first one.
Else (if long is 32 bits and long long is 64 bits) we use second one.
And third: there is a simple optimization which takes fast path not only
for zero as was done before, but for all one-digit numbers.
In all tested cases new code is faster than old one, in many cases by 30%,
in few cases by more than 50% (for example, on x86-32, conversion of
12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit
case.
This patch is based upon an original from Michal Nazarewicz.
[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Douglas W Jones <jones@cs.uiowa.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The '%p' output of the kernel's vsprintf() uses spec.field_width to
determine how many digits to output based on 2 * sizeof(void*) so that all
digits of a pointer are shown. ie. a pointer will be output as
"001A2B3C" instead of "1A2B3C". However, if the '#' flag is used in the
format (%#p), then the code doesn't take into account the width of the
'0x' prefix and will end up outputing "0x1A2B3C" instead of "0x001A2B3C".
This patch reworks the "pointer()" format hook to include 2 characters for
the '0x' prefix if the '#' flag is included.
[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dql->num_queued could change while processing dql_completed().
To provide consistent calculation, added an on stack variable.
Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When below pattern is observed,
TIME
dql_queued() dql_completed() |
a) initial state |
|
b) X bytes queued V
c) Y bytes queued
d) X bytes completed
e) Z bytes queued
f) Y bytes completed
a) dql->limit has already some value and there is no in-flight packet.
b) X bytes queued.
c) Y bytes queued and excess limit.
d) X bytes completed and dql->prev_ovlimit is set and also
dql->prev_num_queued is set Y.
e) Z bytes queued.
f) Y bytes completed. inprogress and prev_inprogress are true.
At f), according to the comment, all_prev_completed becomes
true and limit should be increased. But POSDIFF() ignores
(completed == dql->prev_num_queued) case, so limit is decreased.
Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Denys Fedoryshchenko <denys@visp.net.lb>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
POSDIFF() fails to take into account integer overflow case.
Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Denys Fedoryshchenko <denys@visp.net.lb>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We are not preallocating a sufficient number of nodes.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a spinlock warning is printed we usually get
BUG: spinlock bad magic on CPU#0, modprobe/111
lock: 0xdff09f38, .magic: 00000000, .owner: /0, .owner_cpu: 0
but it's nicer to print the symbol for the lock if we have it so that we
can avoid 'grep dff09f38 /proc/kallsyms' to find out which lock it was.
Use kallsyms to print the symbol name so we get something a bit easier to
read
BUG: spinlock bad magic on CPU#0, modprobe/112
lock: test_lock, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
If the lock is not in kallsyms %ps will fall back to printing the address
directly.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using %ps in a printk format will sometimes fail silently and print the
empty string if the address passed in does not match a symbol that
kallsyms knows about. But using %pS will fall back to printing the full
address if kallsyms can't find the symbol. Make %ps act the same as %pS
by falling back to printing the address.
While we're here also make %ps print the module that a symbol comes from
so that it matches what %pS already does. Take this simple function for
example (in a module):
static void test_printk(void)
{
int test;
pr_info("with pS: %pS\n", &test);
pr_info("with ps: %ps\n", &test);
}
Before this patch:
with pS: 0xdff7df44
with ps:
After this patch:
with pS: 0xdff7df44
with ps: 0xdff7df44
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The code comments for bscnl_emit() and bitmap_scnlistprintf() are
describing snprintf() return semantics, but these functions use
scnprintf() return semantics. Fix that, and document the
bitmap_scnprintf() return value as well.
Cc: Ryota Ozaki <ozaki.ryota@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As long as there is no other non-const variable marked __initdata in the
same compilation unit it doesn't hurt. If there were one however
compilation would fail with
error: $variablename causes a section type conflict
because a section containing const variables is marked read only and so
cannot contain non-const variables.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches