Clemens Ladisch [Sun, 30 Oct 2005 23:03:37 +0000 (15:03 -0800)]
[PATCH] hpet: fix HPET_INFO calls from kernel space
Fix a wrong memory access in hpet_ioctl_common(). It was not possible to use
the HPET_INFO ioctl from kernel space because it always called copy_to_user().
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Cc: Bob Picco <bob.picco@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clemens Ladisch [Sun, 30 Oct 2005 23:03:36 +0000 (15:03 -0800)]
[PATCH] hpet-RTC: cache the comparator register
Reads from an HPET register require a round trip to the south bridge and are
almost as slow as PCI reads. By caching the last value we've written to the
comparator register, we can eliminate all HPET reads from the fast path in the
emulated RTC interrupt handler.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make sure that the RTC timer is in non-periodic mode; some stupid BIOS might
have initialized it to periodic mode.
Furthermore, don't set the SETVAL bit in the config register. This wouldn't
have any effect unless the timer was in period mode (which it isn't), and then
the actual timer frequency would be half that of the desired one because
incrementing the comparator in the interrupt handler would be done after the
hardware has already incremented it itself.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clemens Ladisch [Sun, 30 Oct 2005 23:03:35 +0000 (15:03 -0800)]
[PATCH] hpet-RTC: disable interrupt when no longer needed
When the emulated RTC interrupt is no longer needed, we better disable it;
otherwise, we get a spurious interrupt whenever the timer has rolled over and
reaches the same comparator value.
Having a superfluous interrupt every five minutes doesn't hurt much, but it's
bad style anyway. ;-)
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Acked-by: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clemens Ladisch [Sun, 30 Oct 2005 23:03:34 +0000 (15:03 -0800)]
[PATCH] hpet: allow shared interrupts
This patch adds support for shared HPET interrupts.
The driver previously acknowledged interrupts for both edge and level
interrupts, but didn't actually allow a shared interrupt in the latter case.
We use a new per-timer flag to save whether the timer's interrupt might be
shared, and use it to do the processing required for level interrupts only if
necessary.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Acked-by: Bob Picco <bob.picco@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clemens Ladisch [Sun, 30 Oct 2005 23:03:33 +0000 (15:03 -0800)]
[PATCH] hpet: allow non-power-of-two frequencies
It was only the RTC hardware that restricted interrupt frequencies to a power
of two. There is no reason to take over this restriction into the HPET
driver, so remove the offending check.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Acked-by: Bob Picco <bob.picco@hp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clemens Ladisch [Sun, 30 Oct 2005 23:03:31 +0000 (15:03 -0800)]
[PATCH] HPET: make frequency calculations 32 bit safe
On 32-bit architectures, the multiplication in the argument for
hpet_time_div() often overflows. In the typical case of a 14.32 MHz timer,
this happens when the desired frequency exceeds 61 Hz.
To avoid this multiplication, we can precompute and store the hardware
timer frequency, instead of the period, in the device structure, which
leaves us with a simple division when computing the number of timer ticks.
As a side effect, this also removes a theoretical bug where the timer
interpolator's frequency would be computed as a 32-bit value even if the
HPET frequency is greater than 2^32 Hz (the HPET spec allows up to 10 GHz).
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clemens Ladisch [Sun, 30 Oct 2005 23:03:29 +0000 (15:03 -0800)]
[PATCH] hpet: disallow zero interrupt frequency
Disallow setting an interrupt frequency of zero (which would result in a
division by zero), and disallow enabling the interrupt when the frequency
hasn't yet been set (which would use an interrupt period of zero).
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert most of the remaining "Using plain integer as NULL pointer" sparse
warnings to use NULL. (Not duplicating patches that are already in -mm,
-bird, or -kj.)
Convert isdn driver struct initializer to use C99 syntax.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Kylene Jo Hall [Sun, 30 Oct 2005 23:03:25 +0000 (15:03 -0800)]
[PATCH] tpm: change from pci_dev to dev power management functions
This patch is in support of moving away from the lpc bus pci_dev. The power
management prototypes used by platform drivers is different but the
functionality remains the same.
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>
Kylene Jo Hall [Sun, 30 Oct 2005 23:03:24 +0000 (15:03 -0800)]
[PATCH] tpm: remove pci dependency
Since the tpm does not have it's own pci id we have been consuming the lpc
bus. This is not correct and causes problems to support non lpc bus chips.
This patch removes the dependency on pci_dev from tpm.c The subsequent patches
will stop the supported chips from registering as pci drivers.
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>
Kylene Jo Hall [Sun, 30 Oct 2005 23:03:23 +0000 (15:03 -0800)]
[PATCH] tpm: add status function to allow non-lpc bus chips
This patch is in preparation of supporting chips that are not necessarily on
the lpc bus and thus are not accessed with inb's and outb's. The patch
replaces the call to get the chip's status in the tpm.c file with a vendor
specific status function. The patch also defines the function for each of the
current supported devices.
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>
Yuri Vasilevski [Sun, 30 Oct 2005 23:03:20 +0000 (15:03 -0800)]
[PATCH] fix build on nls free systems
I made a patch that detects if libintl.h (needed for nls) is present on the
host system and if it's not, it nls support is disabled by providing
dummies for the used nls functions.
This way if there is nls support on the host system the *config targets
will build according to Arnaldo Carvalho de Melo's i18n modifications, else
it just uses the original English messages.
I have also made a bug report at kernel's bugzilla:
http://bugzilla.kernel.org/show_bug.cgi?id=5501
And there is a discussion about this problem in Gentoo's bugzilla:
http://bugs.gentoo.org/show_bug.cgi?id=99810
Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A couple of (char *) casts removed in a previous cleanup patch in
lib/string.c:memmove() were actually useful, as they suppressed a couple of
warnings:
assignment discards qualifiers from pointer target type
Fix by declaring the local variable const in the first place, so casts
aren't needed to strip the const qualifier.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Andrew Morton [Sun, 30 Oct 2005 23:03:15 +0000 (15:03 -0800)]
[PATCH] __bread oops fix
If a filesystem passes an idiotic blocksize into bread(), __getblk_slow() will
warn and will return NULL. We have a report (from Hubert Tonneau
<hubert.tonneau@fullpliant.org>) of isofs_fill_super() doing this (passing in
a silly block size) against an unplugged CDROM drive.
But a couple of __getblk_slow() callers forgot to check for the NULL bh, hence
oops.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Roland McGrath [Sun, 30 Oct 2005 23:03:13 +0000 (15:03 -0800)]
[PATCH] posix-cpu-timers: fix overrun reporting
This change corrects an omission in posix_cpu_timer_schedule, so that it
correctly propagates the overrun calculation to where it will get reported
to the user.
Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paul E. McKenney [Sun, 30 Oct 2005 23:03:12 +0000 (15:03 -0800)]
[PATCH] RCU torture-testing kernel module
This patch is a rewrite of the one submitted on October 1st, using modules
(http://marc.theaimsgroup.com/?l=linux-kernel&m=112819093522998&w=2).
This rewrite adds a tristate CONFIG_RCU_TORTURE_TEST, which enables an
intense torture test of the RCU infratructure. This is needed due to the
continued changes to the RCU infrastructure to accommodate dynamic ticks,
CPU hotplug, realtime, and so on. Most of the code is in a separate file
that is compiled only if the CONFIG variable is set. Documentation on how
to run the test and interpret the output is also included.
This code has been tested on i386 and ppc64, and an earlier version of the
code has received extensive testing on a number of architectures as part of
the PREEMPT_RT patchset.
Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Pozsar Balazs [Sun, 30 Oct 2005 23:03:06 +0000 (15:03 -0800)]
[PATCH] fix vgacon blanking
This patch fixes a long-standing vgacon bug: characters with the bright bit
set were left on the screen and not blacked out. All I did was that I
lookuped up some examples on the net about setting the vga palette, and
added the call missing from the linux kernel, but included in all other
ones. It works for me.
You can test this by writing something with the bright set to the
console, for example:
echo -e "\e[1;31mhello there\e[0m"
and then wait for the console to blank itself (by default, after 10 mins
of inactivity), maybe making it faster using
setterm -blank 1
so you only have to wait 1 minute.
Signed-off-by: Pozsar Balazs <pozsy@uhulinux.hu> Cc: James Simmons <jsimmons@infradead.org> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds tests for the return value of sb_getblk() in the ext2/3
filesystems. In fs/buffer.c it is stated that the getblk() function never
fails. However, it does can return NULL in some situations due to I/O
errors, which may lead us to NULL pointer dereferences
Signed-off-by: Glauber de Oliveira Costa <glommer@br.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Are you sure the above diff is correct? It was added somewhere between
2.6.5 and 2.6.8. I think it's wrong.
The only way I can imagine the i_count to be zero in the above path, is
that I_WILL_FREE is set. And if I_WILL_FREE is set, then we must not
increase nr_unused. So I believe the above change is buggy and it will
definitely overstate the number of unused inodes and it should be backed
out.
Note that __writeback_single_inode before calling __sync_single_inode, can
drop the spinlock and we can have both the dirty and locked bitflags clear
here:
spin_unlock(&inode_lock);
__wait_on_inode(inode);
iput(inode);
XXXXXXX
spin_lock(&inode_lock);
}
use inode again here
a construct like the above makes zero sense from a reference counting
standpoint.
Either we don't ever use the inode again after the iput, or the
inode_lock should be taken _before_ executing the iput (i.e. a __iput
would be required). Taking the inode_lock after iput means the iget was
useless if we keep using the inode after the iput.
So the only chance the 2.6 was safe to call __writeback_single_inode
with the i_count == 0, is that I_WILL_FREE is set (I_WILL_FREE will
prevent the VM to free the inode in XXXXX).
Potentially calling the above iput with I_WILL_FREE was also wrong
because it would recurse in iput_final (the second mainline bug).
The below (untested) patch fixes the nr_unused accounting, avoids recursing
in iput when I_WILL_FREE is set and makes sure (with the BUG_ON) that we
don't corrupt memory and that all holders that don't set I_WILL_FREE, keeps
a reference on the inode!
Signed-off-by: Andrea Arcangeli <andrea@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ben Dooks [Sun, 30 Oct 2005 23:02:56 +0000 (15:02 -0800)]
[PATCH] ext3: sparse fixes
Fix warnings from sparse due to un-declared functions that should either
have a header file or have been declared static
fs/ext2/bitmap.c:14:15: warning: symbol 'ext2_count_free' was not declared. Should it be static?
fs/ext2/namei.c:92:15: warning: symbol 'ext2_get_parent' was not declared. Should it be static?
fs/ext3/bitmap.c:15:15: warning: symbol 'ext3_count_free' was not declared. Should it be static?
fs/ext3/namei.c:1013:15: warning: symbol 'ext3_get_parent' was not declared. Should it be static?
fs/ext3/xattr.c:214:1: warning: symbol 'ext3_xattr_block_get' was not declared. Should it be static?
fs/ext3/xattr.c:358:1: warning: symbol 'ext3_xattr_block_list' was not declared. Should it be static?
fs/ext3/xattr.c:630:1: warning: symbol 'ext3_xattr_block_find' was not declared. Should it be static?
fs/ext3/xattr.c:863:1: warning: symbol 'ext3_xattr_ibody_find' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Oleg Nesterov [Sun, 30 Oct 2005 23:02:54 +0000 (15:02 -0800)]
[PATCH] fix de_thread() vs do_coredump() deadlock
de_thread() sends SIGKILL to all sub-threads and waits them to die in 'D'
state. It is possible that one of the threads already dequeued coredump
signal. When de_thread() unlocks ->sighand->lock that thread can enter
do_coredump()->coredump_wait() and cause a deadlock.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Carlos Sanchez [Sun, 30 Oct 2005 23:02:53 +0000 (15:02 -0800)]
[PATCH] Added a Receive_Abort to the Marvell serial driver
Added a Receive_Abort to the Marvell serial driver
Fix occasional input overrun errors on Marvell serial driver
- If the Marvell serial driver is repeatedly started and then stopped it
will occasionally report an input overrun error when started.
- Added a Receive_Abort to the Marvell serial driver to abort previously
received receive errors when re-starting the receive
Acked-by: Mark A. Greer <mgreer@mvista.com> Signed-off-by: Carlos Sanchez <csanchez@mvista.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Roland McGrath [Sun, 30 Oct 2005 23:02:50 +0000 (15:02 -0800)]
[PATCH] wait4 PTRACE_ATTACH race fix
Back about a year ago when I last fiddled heavily with the do_wait code, I
was thinking too hard about the wrong thing and I now think I introduced a
bug whose inverse thought I was fixing.
Apparently noone was looking too hard over much shoulder, so as to cite my
bogus reasoning at the time. In the race condition when PTRACE_ATTACH is
about to steal a child and then the child hits a tracing event (what
my_ptrace_child checks for), the real parent does need to set its flag
noting it has some eligible live children. Otherwise a spurious ECHILD
error is possible, since the child in question is not yet on the
ptrace_children list.
Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Pat Gefre [Sun, 30 Oct 2005 23:02:49 +0000 (15:02 -0800)]
[PATCH] ioc4 serial support - mostly cleanup
Various small mods for the Altix ioc4 serial driver - mostly cleanup:
- remove UIF_INITIALIZED usage
- use the 'lock' from uart_port
- better multiple card support
Signed-off-by: Patrick Gefre <pfg@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I noticed some problems while running ext3 with the debug flag set on.
More precisely, I was unable to umount the filesystem. Some investigation
took me to the patch that follows.
At a first glance , the lock/unlock I've taken out seems really not
necessary, as the main code (outside debug) does not lock the super. The
only additional danger operations that debug code introduces seems to be
related to bitmap, but bitmap operations tends to be all atomic anyway.
I also took the opportunity to fix 2 spelling errors.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David Howells [Sun, 30 Oct 2005 23:02:44 +0000 (15:02 -0800)]
[PATCH] Keys: Get rid of warning in kmod.c if keys disabled
The attached patch gets rid of a "statement without effect" warning when
CONFIG_KEYS is disabled by making use of the return value of key_get().
The compiler will optimise all of this away when keys are disabled.
Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David Howells [Sun, 30 Oct 2005 23:02:44 +0000 (15:02 -0800)]
[PATCH] Keys: Add LSM hooks for key management [try #3]
The attached patch adds LSM hooks for key management facilities. The notable
changes are:
(1) The key struct now supports a security pointer for the use of security
modules. This will permit key labelling and restrictions on which
programs may access a key.
(2) Security modules get a chance to note (or abort) the allocation of a key.
(3) The key permission checking can now be enhanced by the security modules;
the permissions check consults LSM if all other checks bear out.
(4) The key permissions checking functions now return an error code rather
than a boolean value.
(5) An extra permission has been added to govern the modification of
attributes (UID, GID, permissions).
Note that there isn't an LSM hook specifically for each keyctl() operation,
but rather the permissions hook allows control of individual operations based
on the permission request bits.
Key management access control through LSM is enabled by automatically if both
CONFIG_KEYS and CONFIG_SECURITY are enabled.
This should be applied on top of the patch ensubjected:
[PATCH] Keys: Possessor permissions should be additive
Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Export user-defined key operations so that those who wish to define their
own key type based on the user-defined key operations may do so (as has
been requested).
The header file created has been placed into include/keys/user-type.h, thus
creating a directory where other key types may also be placed. Any
objections to doing this?
Signed-Off-By: David Howells <dhowells@redhat.com> Signed-Off-By: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes page_pte_prot and page_pte macros from all
architectures. Some architectures define both, some only page_pte (broken)
and others none. These macros are not used anywhere.
page_pte_prot(page, prot) is identical to mk_pte(page, prot) and
page_pte(page) is identical to page_pte_prot(page, __pgprot(0)).
* The following architectures define both page_pte_prot and page_pte
arm, arm26, ia64, sh64, sparc, sparc64
* The following architectures define only page_pte (broken)
Tejun Heo [Sun, 30 Oct 2005 23:02:40 +0000 (15:02 -0800)]
[PATCH] vm: remove redundant assignment from __pagevec_release_nonlru()
This patch removes redundant assignment from __pagevec_release_nonlru().
pages_to_free.cold is set to pvec->cold by pagevec_init() call right above
the assignment.
Tejun Heo [Sun, 30 Oct 2005 23:02:40 +0000 (15:02 -0800)]
[PATCH] fs: error case fix in __generic_file_aio_read
When __generic_file_aio_read() hits an error during reading, it reports the
error iff nothing has successfully been read yet. This is condition - when
an error occurs, if nothing has been read/written, report the error code;
otherwise, report the amount of bytes successfully transferred upto that
point.
This corner case can be exposed by performing readv(2) with the following
iov.
iov[0] = len0 @ ptr0
iov[1] = len1 @ NULL (or any other invalid pointer)
iov[2] = len2 @ ptr2
When file size is enough, performing above readv(2) results in
len0 bytes from file_pos @ ptr0
len2 bytes from file_pos + len0 @ ptr2
And the return value is len0 + len2. Test program is attached to this
mail.
This patch makes __generic_file_aio_read()'s error handling identical to
other functions.
Andrea Arcangeli [Sun, 30 Oct 2005 23:02:38 +0000 (15:02 -0800)]
[PATCH] ptrace/coredump/exit_group deadlock
I could seldom reproduce a deadlock with a task not killable in T state
(TASK_STOPPED, not TASK_TRACED) by attaching a NPTL threaded program to
gdb, by segfaulting the task and triggering a core dump while some other
task is executing exit_group and while one task is in ptrace_attached
TASK_STOPPED state (not TASK_TRACED yet). This originated from a gdb
bugreport (the fact gdb was segfaulting the task wasn't a kernel bug), but
I just incidentally noticed the gdb bug triggered a real kernel bug as
well.
Most threads hangs in exit_mm because the core_dumping is still going, the
core dumping hangs because the stopped task doesn't exit, the stopped task
can't wakeup because it has SIGNAL_GROUP_EXIT set, hence the deadlock.
To me it seems that the problem is that the force_sig_specific(SIGKILL) in
zap_threads is a noop if the task has PF_PTRACED set (like in this case
because gdb is attached). The __ptrace_unlink does nothing because the
signal->flags is set to SIGNAL_GROUP_EXIT|SIGNAL_STOP_DEQUEUED (verified).
The above info also shows that the stopped task hit a race and got the stop
signal (presumably by the ptrace_attach, only the attach, state is still
TASK_STOPPED and gdb hangs waiting the core before it can set it to
TASK_TRACED) after one of the thread invoked the core dump (it's the core
dump that sets signal->flags to SIGNAL_GROUP_EXIT).
So beside the fact nobody would wakeup the task in __ptrace_unlink (the
state is _not_ TASK_TRACED), there's a secondary problem in the signal
handling code, where a task should ignore the ptrace-sigstops as long as
SIGNAL_GROUP_EXIT is set (or the wakeup in __ptrace_unlink path wouldn't be
enough).
So I attempted to make this patch that seems to fix the problem. There
were various ways to fix it, perhaps you prefer a different one, I just
opted to the one that looked safer to me.
I also removed the clearing of the stopped bits from the zap_other_threads
(zap_other_threads was safe unlike zap_threads). I don't like useless
code, this whole NPTL signal/ptrace thing is already unreadable enough and
full of corner cases without confusing useless code into it to make it even
less readable. And if this code is really needed, then you may want to
explain why it's not being done in the other paths that sets
SIGNAL_GROUP_EXIT at least.
Even after this patch I still wonder who serializes the read of
p->ptrace in zap_threads.
Patch is called ptrace-core_dump-exit_group-deadlock-1.
Paul Jackson [Sun, 30 Oct 2005 23:02:36 +0000 (15:02 -0800)]
[PATCH] cpusets: automatic numa mempolicy rebinding
This patch automatically updates a tasks NUMA mempolicy when its cpuset
memory placement changes. It does so within the context of the task,
without any need to support low level external mempolicy manipulation.
If a system is not using cpusets, or if running on a system with just the
root (all-encompassing) cpuset, then this remap is a no-op. Only when a
task is moved between cpusets, or a cpusets memory placement is changed
does the following apply. Otherwise, the main routine below,
rebind_policy() is not even called.
When mixing cpusets, scheduler affinity, and NUMA mempolicies, the
essential role of cpusets is to place jobs (several related tasks) on a set
of CPUs and Memory Nodes, the essential role of sched_setaffinity is to
manage a jobs processor placement within its allowed cpuset, and the
essential role of NUMA mempolicy (mbind, set_mempolicy) is to manage a jobs
memory placement within its allowed cpuset.
However, CPU affinity and NUMA memory placement are managed within the
kernel using absolute system wide numbering, not cpuset relative numbering.
This is ok until a job is migrated to a different cpuset, or what's the
same, a jobs cpuset is moved to different CPUs and Memory Nodes.
Then the CPU affinity and NUMA memory placement of the tasks in the job
need to be updated, to preserve their cpuset-relative position. This can
be done for CPU affinity using sched_setaffinity() from user code, as one
task can modify anothers CPU affinity. This cannot be done from an
external task for NUMA memory placement, as that can only be modified in
the context of the task using it.
However, it easy enough to remap a tasks NUMA mempolicy automatically when
a task is migrated, using the existing cpuset mechanism to trigger a
refresh of a tasks memory placement after its cpuset has changed. All that
is needed is the old and new nodemask, and notice to the task that it needs
to rebind its mempolicy. The tasks mems_allowed has the old mask, the
tasks cpuset has the new mask, and the existing
cpuset_update_current_mems_allowed() mechanism provides the notice. The
bitmap/cpumask/nodemask remap operators provide the cpuset relative
calculations.
This patch leaves open a couple of issues:
1) Updating vma and shmfs/tmpfs/hugetlbfs memory policies:
These mempolicies may reference nodes outside of those allowed to
the current task by its cpuset. Tasks are migrated as part of jobs,
which reside on what might be several cpusets in a subtree. When such
a job is migrated, all NUMA memory policy references to nodes within
that cpuset subtree should be translated, and references to any nodes
outside that subtree should be left untouched. A future patch will
provide the cpuset mechanism needed to mark such subtrees. With that
patch, we will be able to correctly migrate these other memory policies
across a job migration.
2) Updating cpuset, affinity and memory policies in user space:
This is harder. Any placement state stored in user space using
system-wide numbering will be invalidated across a migration. More
work will be required to provide user code with a migration-safe means
to manage its cpuset relative placement, while preserving the current
API's that pass system wide numbers, not cpuset relative numbers across
the kernel-user boundary.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paul Jackson [Sun, 30 Oct 2005 23:02:33 +0000 (15:02 -0800)]
[PATCH] cpusets: bitmap and mask remap operators
In the forthcoming task migration support, a key calculation will be
mapping cpu and node numbers from the old set to the new set while
preserving cpuset-relative offset.
For example, if a task and its pages on nodes 8-11 are being migrated to
nodes 24-27, then pages on node 9 (the 2nd node in the old set) should be
moved to node 25 (the 2nd node in the new set.)
As with other bitmap operations, the proper way to code this is to provide
the underlying calculation in lib/bitmap.c, and then to provide the usual
cpumask and nodemask wrappers.
This patch provides that. These operations are termed 'remap' operations.
Both remapping a single bit and a set of bits is supported.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paul Jackson [Sun, 30 Oct 2005 23:02:32 +0000 (15:02 -0800)]
[PATCH] cpusets: confine pdflush to its cpuset
This patch keeps pdflush daemons on the same cpuset as their parent, the
kthread daemon.
Some large NUMA configurations put as much as they can of kernel threads
and other classic Unix load in what's called a bootcpuset, keeping the rest
of the system free for dedicated jobs.
This effort is thwarted by pdflush, which dynamically destroys and
recreates pdflush daemons depending on load.
It's easy enough to force the originally created pdflush deamons into the
bootcpuset, at system boottime. But the pdflush threads created later were
allowed to run freely across the system, due to the necessary line in their
startup kthread():
set_cpus_allowed(current, CPU_MASK_ALL);
By simply coding pdflush to start its threads with the cpus_allowed
restrictions of its cpuset (inherited from kthread, its parent) we can
ensure that dynamically created pdflush threads are also kept in the
bootcpuset.
On systems w/o cpusets, or w/o a bootcpuset implementation, the following
will have no affect, leaving pdflush to run on any CPU, as before.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paul Jackson [Sun, 30 Oct 2005 23:02:31 +0000 (15:02 -0800)]
[PATCH] cpusets: simple rename
Add support for renaming cpusets. Only allow simple rename of cpuset
directories in place. Don't allow moving cpusets elsewhere in hierarchy or
renaming the special cpuset files in each cpuset directory.
The usefulness of this simple rename became apparent when developing task
migration facilities. It allows building a second cpuset hierarchy using
new names and containing new CPUs and Memory Nodes, moving tasks from the
old to the new cpusets, removing the old cpusets, and then renaming the new
cpusets to be just like the old names, so that any knowledge that the tasks
had of their cpuset names will still be valid.
Leaf node cpusets can be migrated to other CPUs or Memory Nodes by just
updating their 'cpus' and 'mems' files, but because no cpuset can contain
CPUs or Nodes not in its parent cpuset, one cannot do this in a cpuset
hierarchy without first expanding all the non-leaf cpusets to contain the
union of both the old and new CPUs and Nodes, which would obfuscate the
one-to-one migration of a task from one cpuset to another required to
correctly migrate the physical page frames currently allocated to that
task.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paul Jackson [Sun, 30 Oct 2005 23:02:30 +0000 (15:02 -0800)]
[PATCH] cpusets: dual semaphore locking overhaul
Overhaul cpuset locking. Replace single semaphore with two semaphores.
The suggestion to use two locks was made by Roman Zippel.
Both locks are global. Code that wants to modify cpusets must first
acquire the exclusive manage_sem, which allows them read-only access to
cpusets, and holds off other would-be modifiers. Before making actual
changes, the second semaphore, callback_sem must be acquired as well. Code
that needs only to query cpusets must acquire callback_sem, which is also a
global exclusive lock.
The earlier problems with double tripping are avoided, because it is
allowed for holders of manage_sem to nest the second callback_sem lock, and
only callback_sem is needed by code called from within __alloc_pages(),
where the double tripping had been possible.
This is not quite the same as a normal read/write semaphore, because
obtaining read-only access with intent to change must hold off other such
attempts, while allowing read-only access w/o such intention. Changing
cpusets involves several related checks and changes, which must be done
while allowing read-only queries (to avoid the double trip), but while
ensuring nothing changes (holding off other would be modifiers.)
This overhaul of cpuset locking also makes careful use of task_lock() to
guard access to the task->cpuset pointer, closing a couple of race
conditions noticed while reading this code (thanks, Roman). I've never
seen these races fail in any use or test.
See further the comments in the code.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove a rather hackish depth counter on cpuset locking. The depth counter
was avoiding a possible double trip on the global cpuset_sem semaphore. It
worked, but now an improved version of cpuset locking is available, to come
in the next patch, using two global semaphores.
This patch reverses "cpuset semaphore depth check deadlock fix"
The kernel still works, even after this patch, except for some rare and
difficult to reproduce race conditions when agressively creating and
destroying cpusets marked with the notify_on_release option, on very large
systems.
Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Kirill Korotaev [Sun, 30 Oct 2005 23:02:26 +0000 (15:02 -0800)]
[PATCH] proc: fix of error path in proc_get_inode()
This patch fixes incorrect error path in proc_get_inode(), when module
can't be get due to being unloaded. When try_module_get() fails, this
function puts de(!) and still returns inode with non-getted de.
There are still unresolved known bugs in proc yet to be fixed:
- proc_dir_entry tree is managed without any serialization
- create_proc_entry() doesn't setup de->owner anyhow,
so setting it later manually is inatomic.
- looks like almost all modules do not care whether
it's de->owner is set...
If the requested I/O scheduler is already in place, elevator_switch simply
leaves the queue alone, and returns. However, it forgets to call
elevator_put, so
Make the pid argument a long as on every other arcihtecture. Despite pid_t
beeing a 32bit type even on 64bit parisc this is not an ABI change due to
the parisc calling conventions. And even if it did it wouldn't matter too
much because 64bit userspace on parisc is in an embrionic stage.
Acked-by: Matthew Wilcox <matthew@wil.cx> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a kconfig submenu to select the default I/O scheduler, in case
anticipatory is not compiled in or another default is preferred. Also,
since no-op is always available, we should use it whenever the selected
default is not.
Signed-off-by: Nate Diller <nate@namesys.com> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Vadim Lobanov [Sun, 30 Oct 2005 23:02:18 +0000 (15:02 -0800)]
[PATCH] Unify sys_tkill() and sys_tgkill()
The majority of the sys_tkill() and sys_tgkill() function code is
duplicated between the two of them. This patch pulls the duplication out
into a separate function -- do_tkill() -- and lets sys_tkill() and
sys_tgkill() be simple wrappers around it. This should make it easier to
maintain in light of future changes.
Eric Dumazet [Sun, 30 Oct 2005 23:02:16 +0000 (15:02 -0800)]
[PATCH] reduce sizeof(struct file)
Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead
in a memory location that is not anymore used at call_rcu(&f->f_rcuhead,
file_free_rcu) time, to reduce the size of this critical kernel object.
The trick I used is to move f_rcuhead and f_list in an union called f_u
The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list
becomes f_u.f_list
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Randy Dunlap [Sun, 30 Oct 2005 23:02:15 +0000 (15:02 -0800)]
[PATCH] clarify menuconfig /(search) help text
Add explicit text about
- where menuconfig '/' (search) searches for strings,
- that substrings are allowed, and
- that regular expressions are supported.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The first two hunks of the patch really belongs in patch 1, but I missed
them on the first pass and instead of redoing all 3 patches I stuck them in
this one.
Removes a few pointless register keywords. register is merely a compiler
hint that access to the variable should be optimized, but gcc (3.3.6 in my
case) generates the exact same code with and without the keyword, and even
if gcc did something different with register present I think it is doubtful
we would want to optimize access to these variables - especially since this
is generic library code and there are supposed to be optimized versions in
asm/ for anything that really matters speed wise.
(akpm: iirc, keyword register is a gcc no-op unless using -O0)
[PATCH] Don't uselessly export task_struct to userspace in core dumps
task_struct is an internal structure to the kernel with a lot of good
information, that is probably interesting in core dumps. However there is
no way for user space to know what format that information is in making it
useless.
I grepped the GDB 6.3 source code and NT_TASKSTRUCT while defined is not
used anywhere else. So I would be surprised if anyone notices it is
missing.
In addition exporting kernel pointers to all the interesting kernel data
structures sounds like the very definition of an information leak. I
haven't a clue what someone with evil intentions could do with that
information, but in any attack against the kernel it looks like this is the
perfect tool for aiming that attack.
So since NT_TASKSTRUCT is useless as currently defined and is potentially
dangerous, let's just not export it.
(akpm: Daniel Jacobowitz <dan@debian.org> "would be amazed" if anything was
using NT_TASKSTRUCT).
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>
[PATCH] Use alloc_percpu to allocate workqueues locally
This patch makes the workqueus use alloc_percpu instead of an array. The
workqueues are placed on nodes local to each processor.
The workqueue structure can grow to a significant size on a system with
lots of processors if this patch is not applied. 64 bit architectures with
all debugging features enabled and configured for 512 processors will not
be able to boot without this patch.
Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Garzik [Sun, 30 Oct 2005 23:01:51 +0000 (15:01 -0800)]
[PATCH] remove some more check_region stuff
Removed some more references to check_region().
I checked these changes into the 'checkreg' branch of
rsync://rsync.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6.git
The only valid references remaining are in:
drivers/scsi/advansys.c
drivers/scsi/BusLogic.c
drivers/cdrom/sbpcd.c
sound/oss/pss.c
Remove last vestiges of ide_check_region()
drivers/char/specialix: trim trailing whitespace
drivers/char/specialix: eliminate use of check_region()
Remove outdated and unused references to check_region()
[sound oss] remove check_region() usage from cs4232, wavfront
[netdrvr eepro] trim trailing whitespace
[netdrvr eepro] remove check_region() usage
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
projects / karo-tx-linux.git / log