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Create a "taskstats" interface based on generic netlink (NETLINK_GENERIC
family), for getting statistics of tasks and thread groups during their
lifetime and when they exit. The interface is intended for use by multiple
accounting packages though it is being created in the context of delay
accounting.
This patch creates the interface without populating the fields of the data
that is sent to the user in response to a command or upon the exit of a task.
Each accounting package interested in using taskstats has to provide an
additional patch to add its stats to the common structure.
[akpm@osdl.org: cleanups, Kconfig fix]
Signed-off-by: Shailabh Nagar <nagar@us.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Two utilities for simplifying usage of NETLINK_GENERIC interface.
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Make the task-related schedstats functions callable by delay accounting even
if schedstats collection isn't turned on. This removes the dependency of
delay accounting on schedstats.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Unlike earlier iterations of the delay accounting patches, now delays are only
collected for the actual I/O waits rather than try and cover the delays seen
in I/O submission paths.
Account separately for block I/O delays incurred as a result of swapin page
faults whose frequency can be affected by the task/process' rss limit. Hence
swapin delays can act as feedback for rss limit changes independent of I/O
priority changes.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Initialization code related to collection of per-task "delay" statistics which
measure how long it had to wait for cpu, sync block io, swapping etc. The
collection of statistics and the interface are in other patches. This patch
sets up the data structures and allows the statistics collection to be
disabled through a kernel boot parameter.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add another list utility function to check for last element in a list.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add frame buffer driver for the 2700G LCD controller present on CompuLab
CM-X270 computer module.
[adaplas]
- Add more informative help text to Kconfig
- Make DEBUG a Kconfig option as FB_MBX_DEBUG
- Remove #include mbxdebug.c, this is frowned upon
- Remove redundant casts
- Arrange #include's alphabetically
- Trivial whitespace
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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After some discussion on the actual meaning of the filesystem class
security check in try context mount it was determined that the checks for
the context= mount options were not correct if fscontext mount option had
already been used.
When labeling the superblock we should be checking relabel_from and
relabel_to. But if the superblock has already been labeled (with
fscontext) then context= is actually labeling the inodes, and so we should
be checking relabel_from and associate. This patch fixes which checks are
called depending on the mount options.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The lockdep options should depend on DEBUG_KERNEL since:
- they are kernel debugging options and
- they do otherwise break the DEBUG_KERNEL menu structure
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Fix the start and len variables that should be using the new
resource_size_t.
Signed_off_by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Some machine manufacturers are not sticking to the TCG specifications and
including an ACPI DSDT entry for the TPM which allows PNP discovery of the
device.
Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Under stress testing I found that the interrupt is not always cleared.
Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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It's way past time to bump it to 8. Everyone had been warned - for
months now.
RH kernels have had this for more than a year.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add actual mailing list email addresses for the 4 that were only listing a
web page.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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kfree(devname) on the misc_register() failure path. Otherwise it is lost
forever.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Kylene Jo Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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On platforms that have __ARCH_WANT_UNLOCKED_CTXSW set and want to implement
lock validator support there's a bug in rq->lock handling: in this case we
dont 'carry over' the runqueue lock into another task - but still we did a
spinlock_release() of it. Fix this by making the spinlock_release() in
context_switch() dependent on !__ARCH_WANT_UNLOCKED_CTXSW.
(Reported by Ralf Baechle on MIPS, which has __ARCH_WANT_UNLOCKED_CTXSW.
This fixes a lockdep-internal BUG message on such platforms.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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- rename EXPORTed gpio vtables from {scx200,pc8736x}_access to _gpio_ops new
name is much closer to the vtable-name struct nsc_gpio_ops, should be
clearer. Also rename the _fops vtable var to _fileops to better
disambiguate it from the gpio vtable.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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- pure cosmetics: lose needless newlines.
- rename EXPORTed gpio vtables from {scx200,pc8736x}_access to _gpio_ops new
name is much closer to the vtable-name struct nsc_gpio_ops, should be
clearer. Also rename the _fops vtable var to _fileops to better
disambiguate it from the gpio vtable.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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enough
drops gpio_set_high, gpio_set_low from the nsc_gpio_ops vtable. While we
can't drop them from scx200_gpio (or can we?), we dont need them for new users
of the exported vtable; gpio_set(1), gpio_set(0) work fine.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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pci_dac_set_dma_mask() gives only a single match in the whole kernel tree
and that's in this doc file. The best candidate for replacement is
pci_dac_dma_supported().
Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Greg KH <greg@kroah.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Documentation for register_chrdev() was missing completely.
[akpm@osdl.org: kerneldocification]
Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Currently, the code in lib/idr.c uses a bare spin_lock(&idp->lock) to do
internal locking. This is a nasty trap for code that might call idr
functions from different contexts; for example, it seems perfectly
reasonable to call idr_get_new() from process context and idr_remove() from
interrupt context -- but with the current locking this would lead to a
potential deadlock.
The simplest fix for this is to just convert the idr locking to use
spin_lock_irqsave().
In particular, this fixes a very complicated locking issue detected by
lockdep, involving the ib_ipoib driver's priv->lock and dev->_xmit_lock,
which get involved with the ib_sa module's query_idr.lock.
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Zach Brown <zach.brown@oracle.com>,
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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On systems with block devices containing a slash (virtual dasd, cciss,
etc), reiserfs will fail to initialize /proc/fs/reiserfs/<dev> due to it
being interpreted as a subdirectory. The generic block device code changes
the / to ! for use in the sysfs tree. This patch uses that convention.
Tested by making dm devices use dm/<number> rather than dm-<number>
[akpm@osdl.org: name variables consistently]
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add the DRVNAME define to remove the two separate references of the driver
name by string, and move the .driver.owner into the existing .driver
sub-structure.
Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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IRQs must be disabled before taking ->siglock.
Noticed by lockdep.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Resolve problems seen w/ APM suspend.
Due to resume initialization ordering, its possible we could get a timer
interrupt before the timekeeping resume() function is called. This patch
ensures we don't do any timekeeping accounting before we're fully resumed.
(akpm: fixes the machine-freezes-on-APM-resume bug)
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Remove the scx200_gpio's cdev-array & ksalloc, replacing it with a single
static struct cdev, which is sufficient for all the pins.
cdev_put is commented out since kernel wont link properly with it, and its
apparently not needed.
With these patches, this driver continues to work with Chris Boot's
leds_48xx driver.
Signed-off-by Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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this patch is mostly cleanup of scx200_gpio :
- drop #include <linux/config.h>
- s/DEVNAME/DRVNAME/ apparently a convention
- replace variable num_pins with #define MAX_PINS
- s/dev/devid/ to clarify that its a dev_t, not a struct device dev.
- move devid = MKDEV(major,0) into branch where its needed.
2 minor 'changes' :
- reduced MAX_PINS from 64 to 32. Ive never tested other pins, and
theyre all multiplexed with other functions, some of which may be in use
on my soekris 4801, so I dont know what testing should yield.
- +EXPORT_SYMBOL(scx200_access);
This exposes the driver's vtable, which another driver can use along
with #include <linux/nsc_gpio.h>, to manipulate a gpio-pin.
Signed-off-by Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Christoph Hellwig:
open_softirq just enables a softirq. The softirq array is statically
allocated so to add a new one you would have to patch the kernel. So
there's no point to keep this export at all as any user would have to
patch the enum in include/linux/interrupt.h anyway.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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When CONFIG_RT_MUTEX_TESTER is enabled kernel refuses to suspend the
machine because it's unable to freeze the rt-test-* threads.
Add try_to_freeze() after schedule() so that the threads will be freezed
correctly; I've tested the patch and it lets the notebook suspends and
resumes nicely.
Signed-off-by: Luca Tettamanti <kronos.it@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The delete partition IOCTL takes the bd_mutex for both the disk and the
partition; these have an obvious hierarchical relationship and this patch
annotates this relationship for lockdep.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add support for the I2C-attached Intersil ISL1208 RTC chip.
[akpm@osdl.org: cleanups, fixlets]
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Make the ramdisk blocksize configurable at kernel compilation time rather
than only at boot or module load time, like a couple of the other ramdisk
options. I found this handy awhile back but thought little of it, until
recently asked by a few of the testing folks here to be able to do the same
thing for their automated test setups.
The Kconfig comment is largely lifted from comments in rd.c, and hopefully
this will increase the chances of making folks aware that the default value
often isn't a great choice here (for increasing values of PAGE_SIZE, even
moreso).
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The default ramdisk blocksize is actually 1024, not 512 bytes. Also fixes
up some trailing whitespace issues.
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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nommu.c needs to export two more symbols for drivers to use:
remap_pfn_range and unmap_mapping_range.
Signed-off-by: Luke Yang <luke.adi@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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There's no excuse for userspace abusing this kernel header -- the kernel's
headers are not intended to provide a library of helper routines for
userspace. Using <asm/io.h> from userspace is broken on most architectures
anyway. Just say 'no'.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This isn't suitable for userspace to see -- the kernel headers are not a
random library of stuff for userspace; they're only there to define the
kernel<->user ABI for system libraries and tools. Anything which _was_
abusing asm/atomic.h from userspace was probably broken anyway -- as it often
didn't even give atomic operation.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Remove asm/irq.h from the exported headers -- there was never any good reason
for it to have been listed.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Relax the CPU in the del_timer_sync() busywait loop.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Remove the now-unneeded kthread_stop_sem().
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Got a customer bug report (https://bugzilla.novell.com/190296) about kernel
symbols longer than 127 characters which end up in a string buffer that is
not NULL terminated, leading to garbage in /proc/kallsyms. Using strlcpy
prevents this from happening, even though such symbols still won't come out
right.
A better fix would be to not use a fixed-size buffer, but it's probably not
worth the trouble. (Modversion'ed symbols even have a length limit of 60.)
[bunk@stusta.de: build fix]
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Clean up whitespace and return syntax in os.h.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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On top of the previous biarch changes for UML, this makes the preprocessor
changes a bit cleaner. Specify the 64-bit build in CPPFLAGS on the x86_64
SUBARCH, rather than #undef'ing i386. Compile-tested with i386 and x86_64
SUBARCHs.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The UML_SETJMP macro was requiring its users to pass in a argument which it
could supply itself, since it wasn't used outside that invocation of the
macro.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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On i386, the user space accessor functions copy_from/to_user() both invoke
might_sleep(), do a quick sanity check, and then pass the work on to their
__copy_from/to_user() counterparts, which again invoke might_sleep().
Given that no actual work happens between these two calls, it is best to
eliminate one of the redundant might_sleep()s.
Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch removes the foolish assumption that SMP implied local apics.
That assumption is not-true on the Voyager subarch. This makes that
dependency explicit, and allows the code to build.
What gets disabled is just an optimization to get better crash dumps so the
support should work if there is a kernel that will initialization on the
voyager subarch under those harsh conditions.
Hopefully we can figure out how to initialize apics in init_IRQ and remove
the need to disable io_apics and this dependency.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Signed-off-by: Catalin Marinas <catalin.marinas@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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handle_BUG() tries to print file and line number even when they're not
available (CONFIG_DEBUG_BUGVERBOSE is not set.) Change this to print a
message stating info is unavailable instead of printing a misleading
message.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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There is a race condition that showed up in a threaded JIT environment.
The situation is that a process with a JIT code page forks, so the page is
marked read-only, then some threads are created in the child. One of the
threads attempts to add a new code block to the JIT page, so a
copy-on-write fault is taken, and the kernel allocates a new page, copies
the data, installs the new pte, and then calls lazy_mmu_prot_update() to
flush caches to make sure that the icache and dcache are in sync.
Unfortunately, the other thread runs right after the new pte is installed,
but before the caches have been flushed. It tries to execute some old JIT
code that was already in this page, but it sees some garbage in the i-cache
from the previous users of the new physical page.
Fix: we must make the caches consistent before installing the pte. This is
an ia64 only fix because lazy_mmu_prot_update() is a no-op on all other
architectures.
Signed-off-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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