Commit Graph

113 Commits

Author SHA1 Message Date
Heiko Carstens cd2d2bf657 [PATCH] s390: fix compat syscall wrapper
Patch 9ad11ab48b changes the type of the first
argument of some compat syscalls from int to unsigned int.  Add these changes
to the s390 compat wrapper as well.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:01 -08:00
Heiko Carstens 54dfe5dd9a [PATCH] s390: Add support for new syscalls/TIF_RESTORE_SIGMASK
Add support for the new *at, pselect6 and ppoll system calls.  This includes
adding required support for TIF_RESTORE_SIGMASK.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:24 -08:00
Heiko Carstens 1ab865c146 [PATCH] s390: New default configuration
New default configuration.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:24 -08:00
Jan Glauber 32f65f2746 [PATCH] s390: monotonic_clock interface
Add monotonic_clock interface, used by the hangcheck-timer.  On s390 this is
the same as sched_clock().

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:24 -08:00
Jan Glauber 9dbafa5368 [PATCH] s390: overflow in sched_clock
The least significant bit of the TOD clock value returned by get_clock
is the 4096th part of a microsecond. To get to nanoseconds the value
needs to be divided by 4096 and multiplied with 1000.

The current method multiplies first and then shifts the value to make the
result as precise as possible.  The disadvantage is that the multiplication
with 1000 will overflow shortly after 52 days.  sched_clock is used by the
scheduler for time stamp deltas, if an overflow occurs between two time stamps
the scheduler will get confused.

With the patch the problem occurs only after approx.  one year, so the chance
to run into this overflow is extremly low.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:23 -08:00
Heiko Carstens e018ba1fce [PATCH] s390: Remove CVS generated information
- Remove all CVS generated information like e.g. revision IDs from
  drivers/s390 and include/asm-s390 (none present in arch/s390).

- Add newline at end of arch/s390/lib/Makefile to avoid diff message.

Acked-by: Andreas Herrmann <aherrman@de.ibm.com>
Acked-by: Frank Pavlic <pavlic@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:23 -08:00
Martin Schwidefsky 1f1c12afe5 [PATCH] s390: cputime misaccounting
finish_arch_switch needs to update the user cpu time as well, not just the
system cpu time.  Otherwise the partial user cpu time of a process that is
stored in the lowcore will be (mis-)accounted to the next process.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:09 -08:00
Martin Schwidefsky 53df751ccd [PATCH] s390: add dummy pm_power_off
Define a dummy pm_power_off pointer to make sys_reboot happy.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:09 -08:00
Martin Schwidefsky 0152fb3760 [PATCH] s390: spinlock fixes
Remove useless spin_retry_counter and fix compilation for UP kernels.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:09 -08:00
Alexey Dobriyan 68c1191778 [PATCH] s390: fix cpcmd calls on UP
Add missing fourth argument to cpcmd calls under !CONFIG_SMP.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:09 -08:00
Heiko Carstens eb33c190c2 [PATCH] s390: show_task oops
The show_task function walks the kernel stack backchain of processes assuming
that the processes are not running.  Since this assumption is not correct
walking the backchain can lead to an addressing exception and therefore to a
kernel hang.  So prevent the kernel hang (you still get incorrect results)
verity that all read accesses are within the bounds of the kernel stack before
performing them.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:08 -08:00
Jan Glauber 7ffbc9da13 [PATCH] s390: sha256 crypto code fix
Fix processing of messages larger than 2 * SHA256_BLOCK_SIZE.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:08 -08:00
Jan Glauber fda5e14259 [PATCH] s390: aes crypto code fixes
Call KM[C] only with a multiple of block size.  Check return value of KM[C]
instructions and complain about erros

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:08 -08:00
Jan Glauber b8dc6038ff [PATCH] s390: des crypto code speedup
Provide ECB and CBC encrypt / decrypt functions to crypto API to speed up our
hardware accelerated DES implementation.  This new functions allow the crypto
API to call ECB / CBC directly with large blocks in difference to the old
functions that were calles with algorithm block size (8 bytes for DES).

This is up to factor 10 faster than our old hardware implementation :)

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:08 -08:00
Jan Glauber c1357833bf [PATCH] s390: des crypto code cleanup
Beautify the s390 in-kernel-crypto des code.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:08 -08:00
Al Viro 30af7120fe [PATCH] s390: task_stack_page()
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>
2006-01-12 09:08:54 -08:00
Al Viro c7584fb6b4 [PATCH] s390: task_pt_regs()
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>
2006-01-12 09:08:54 -08:00
Randy Dunlap a941564458 [PATCH] capable/capability.h (arch/)
arch: Use <linux/capability.h> where capable() is used.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:14 -08:00
Christoph Hellwig 7ff92053dd [PATCH] don't include ioctl32.h in drivers
These days ioctl32.h is only used for communication of fs/compat.c and
fs/compat_ioctl.c and doesn't contain anything of interest to drivers.

Remove inclusion in various drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:34 -08:00
Christoph Hellwig e6a6d2efcb [PATCH] sanitize building of fs/compat_ioctl.c
Now that all these entries in the arch ioctl32.c files are gone [1], we can
build fs/compat_ioctl.c as a normal object and kill tons of cruft.  We need a
special do_ioctl32_pointer handler for s390 so the compat_ptr call is done.
This is not needed but harmless on all other architectures.  Also remove some
superflous includes in fs/compat_ioctl.c

Tested on ppc64.

[1] parisc still had it's PPP handler left, which is not fully correct
    for ppp and besides that ppp uses the generic SIOCPRIV ioctl so it'd
    kick in for all netdevice users.  We can introduce a proper handler
    in one of the next patch series by adding a compat_ioctl method to
    struct net_device but for now let's just kill it - parisc doesn't
    compile in mainline anyway and I don't want this to block this
    patchset.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:33 -08:00
Christoph Hellwig 8262037f40 [PATCH] add ->compat_ioctl to dasd
Add a compat_ioctl method to the dasd driver so the last entries in
arch/s390/kernel/compat_ioctl.c can go away.  Unlike the previous attempt this
one does not replace the ioctl method with an unlocked_ioctl method so that
the ioctl_by_bdev calls in s390 partition code continue to work.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:32 -08:00
Christoph Hellwig 3a0f69d59b [PATCH] common compat_sys_timer_create
The comment in compat.c is wrong, every architecture provides a
get_compat_sigevent() for the IPC compat code already.

This basically moves the x86_64 version to common code and removes all the
others.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:32 -08:00
Christoph Hellwig f042e0f80b [PATCH] ->compat_ioctl for 390 tape_char
The only own ioctl, TAPE390_DISPLAY, is compat_clean, everything else is
routed through common translation code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:31 -08:00
Christoph Hellwig 51a990588a [PATCH] remove TIOCGSERIAL/TIOCSSERIAL compat_ioctl entries for 390
These ioctls are definitely not compat clean, but we already have a proper
handler in common code, over-riding it in architecture code is
counter-productive.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:31 -08:00
Christoph Hellwig 0f75e00c9a [PATCH] switch fs3270 to ->compat_ioctl
Again easy because all ioctls are compat clean.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:31 -08:00
Vivek Goyal cc57165874 [PATCH] kdump: dynamic per cpu allocation of memory for saving cpu registers
- In case of system crash, current state of cpu registers is saved in memory
  in elf note format.  So far memory for storing elf notes was being allocated
  statically for NR_CPUS.

- This patch introduces dynamic allocation of memory for storing elf notes.
  It uses alloc_percpu() interface.  This should lead to better memory usage.

- Introduced based on Andi Kleen's and Eric W. Biederman's suggestions.

- This patch also moves memory allocation for elf notes from architecture
  dependent portion to architecture independent portion.  Now crash_notes is
  architecture independent.  The whole idea is that size of memory to be
  allocated per cpu (MAX_NOTE_BYTES) can be architecture dependent and
  allocation of this memory can be architecture independent.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:26 -08:00
akpm@osdl.org df2e71fb91 [PATCH] dump_thread() cleanup
)

From: Adrian Bunk <bunk@stusta.de>

- create one common dump_thread() prototype in kernel.h

- dump_thread() is only used in fs/binfmt_aout.c and can therefore be
  removed on all architectures where CONFIG_BINFMT_AOUT is not
  available

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:25 -08:00
Adrian Bunk 2308acca65 [PATCH] "tiny-make-id16-support-optional" fixes
It seems the "make UID16 support optional" patch was checked when it
edited the -tiny tree some time ago, but it wasn't checked whether it
still matches the current situation when it was submitted for inclusion
in -mm. This patch fixes the following bugs:
- ARCH_S390X does no longer exist, nowadays this has to be expressed
  through (S390 && 64BIT)
- in five architecture specific Kconfig files the UID16 options
  weren't removed

Additionally, it changes the fragile negative dependencies of UID16 to
positive dependencies (new architectures are more likely to not require
UID16 support).

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:23 -08:00
Christoph Hellwig 6b9c7ed848 [PATCH] use ptrace_get_task_struct in various places
The ptrace_get_task_struct() helper that I added as part of the ptrace
consolidation is useful in variety of places that currently opencode it.
Switch them to the common helpers.

Add a ptrace_traceme() helper that needs to be explicitly called, and simplify
the ptrace_get_task_struct() interface.  We don't need the request argument
now, and we return the task_struct directly, using ERR_PTR() for error
returns.  It's a bit more code in the callers, but we have two sane routines
that do one thing well now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:51 -08:00
Martin Schwidefsky 347a8dc3b8 [PATCH] s390: cleanup Kconfig
Sanitize some s390 Kconfig options.  We have ARCH_S390, ARCH_S390X,
ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT.  Replace these 6 options by
S390, 64BIT and COMPAT.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:53 -08:00
Frank Pavlic 8129ee1642 [PATCH] s390: qdio V=V pass-through
New feature V=V qdio pass-through.

QDIO and HiperSockets processing in z/VM V=V guest environments (as well as
V=R with z/VM running in LPAR mode) requires shadowing of all QDIO
architecture queue elements.  Especially the shadowing of SBALs and SLSBs
structures in the hypervisor, and the need to issue SIGA SYNC operations to
observe state changes, eventually causes significant CPU processing overhead
in the hypervisor.

The QDIO pass-through support for V=V guests avoids the shadowing of SBALs and
SLSBs.  This significantly reduces the hypervisor overhead for QDIO based I/O.

Signed-off-by: Frank Pavlic <pavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:51 -08:00
Jan Glauber bf754ae8ef [PATCH] s390: aes support
Add support for the hardware accelerated AES crypto algorithm.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:50 -08:00
Jan Glauber 0a497c17fe [PATCH] s390: sha256 support
Add support for the hardware accelerated sha256 crypto algorithm.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:50 -08:00
Jan Glauber c1e26e1ef7 [PATCH] s390: in-kernel crypto rename
Replace all references to z990 by s390 in the in-kernel crypto files in
arch/s390/crypto.  The code is not specific to a particular machine (z990) but
to the s390 platform.  Big diff, does nothing..

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:50 -08:00
Andreas Krebbel d0f4c16feb [PATCH] s390: add oprofile callgraph support
Signed-off-by: Andreas Krebbel <krebbel1@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:50 -08:00
Martin Schwidefsky 089545f0c7 [PATCH] s390: cputime_t fixes
There are some more places where the use of cputime_t instead of an integer
type and the associated macros is necessary for the virtual cputime accounting
on s390.  Affected are the s390 specific appldata code and BSD process
accounting.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:49 -08:00
Martin Schwidefsky 088c4ec16a [PATCH] s390: update default configuration
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:49 -08:00
Cedric Le Goater 4e3df37e7f [PATCH] s390: rt_sigreturn fix
Check return code of do_sigaltstack and force a SIGSEGV if it is -EFAULT.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:49 -08:00
Martin Schwidefsky a63a4931c3 [PATCH] s390: uaccess warnings
Convert __access_ok to an inline C function and change __get_user primitive to
avoid uaccess compiler warnings.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:49 -08:00
Martin Schwidefsky 973bd99375 [PATCH] s390: atomic primitives
Hugh Dickins <hugh@veritas.com>

Fix the broken atomic_cmpxchg primitive.  Add atomic_sub_and_test,
atomic64_sub_return, atomic64_sub_and_test, atomic64_cmpxchg,
atomic64_add_unless and atomic64_inc_not_zero.  Replace old style
atomic_compare_and_swap by atomic_cmpxchg.  Shorten the whole header by
defining most primitives with the two inline functions atomic_add_return and
atomic_sub_return.

In addition this patch contains the s390 related fixes of Hugh's "mm: fill
arch atomic64 gaps" patch.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:48 -08:00
Nick Piggin 64c7c8f885 [PATCH] sched: resched and cpu_idle rework
Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid.  Improves efficiency of
resched_task and some cpu_idle routines.

* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
  and as we hold it during resched_task, then there is no need for an
  atomic test and set there. The only other time this should be set is
  when the task's quantum expires, in the timer interrupt - this is
  protected against because the rq lock is irq-safe.

- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
  won't get unset until the task get's schedule()d off.

- If we are running on the same CPU as the task we resched, then set
  TIF_NEED_RESCHED and no further action is required.

- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
  after TIF_NEED_RESCHED has been set, then we need to send an IPI.

Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.

* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
  becomes true, explicitly call schedule(). This makes things a bit clearer
  (IMO), but haven't updated all architectures yet.

- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
  to the resched_task rules, this isn't needed (and actually breaks the
  assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
  held). So remove that. Generally one less locked memory op when switching
  to the idle thread.

- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
  most polling idle loops. The above resched_task semantics allow it to be
  set until before the last time need_resched() is checked before going into
  a halt requiring interrupt wakeup.

  Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
  can be always left set, completely eliminating resched IPIs when rescheduling
  the idle task.

  POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00
Nick Piggin 5bfb5d690f [PATCH] sched: disable preempt in idle tasks
Run idle threads with preempt disabled.

Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?

Might fix the CPU hotplugging hang which Nigel Cunningham noted.

We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.

After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep.  The CPU will continue executing
previous idle and have no chance to call play_dead.

By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.

From: alexs <ashepard@u.washington.edu>

  PPC build fix

From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>

  MIPS build fix

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00
Adrian Bunk 4448aaf0fa [PATCH] s390: "extern inline" -> "static inline"
"extern inline" -> "static inline"

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:52 -08:00
Al Viro 330d57fb98 [PATCH] Fix sysctl unregistration oops (CVE-2005-2709)
You could open the /proc/sys/net/ipv4/conf/<if>/<whatever> file, then
wait for interface to go away, try to grab as much memory as possible in
hope to hit the (kfreed) ctl_table.  Then fill it with pointers to your
function.  Then do read from file you've opened and if you are lucky,
you'll get it called as ->proc_handler() in kernel mode.

So this is at least an Oops and possibly more.  It does depend on an
interface going away though, so less of a security risk than it would
otherwise be.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-08 17:57:30 -08:00
Jesper Juhl b2325fe1b7 [PATCH] kfree cleanup: arch
This is the arch/ part of the big kfree cleanup patch.

Remove pointless checks for NULL prior to calling kfree() in arch/.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:06 -08:00
Heiko Carstens 0ad775dbba [PATCH] s390: merge common parts of head.S and head64.S
Merge common parts of head.S and head64.S into head.S and move architecture
specific parts to head31.S and head64.S respectively.  Saves us ~500 lines
of duplicated assembly code.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:34 -08:00
Martin Schwidefsky d4b6899678 [PATCH] s390: remove pagex support
Remove pagex pseudo page fault code.  It does not work together with the
system call speedup that makes the complete system call path enabled for
interrupts.  To make pagex and the syscall speedup code work together we would
have to add code to the program check handler to do a critical section cleanup
like the asynchronous interrupt code.  This would make program checks slower.
Not what we want.

Newer versions of z/VM have the improved pfault pseudo page fault interface.
This replaces the old pagex interface and does not have the problem.  So its
better to just rip out the pagex code.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:33 -08:00
Heiko Carstens 9b4554aa21 [PATCH] s390: memory query wait psw
Don't switch back to 24 bit addressing mode when waiting for an external
interrupt and set the correct bit in wait PSW (external mask instead of I/O
mask).

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:33 -08:00
Martin Schwidefsky 1b44e98d7d [PATCH] s390: stop_hz_timer vs. xtime updates
The calculation of the value return by next_timer_interrupt from jiffies to
jiffies_64 is racy against xtime updates.  We need to protect the calculation
with read_seqbegin/read_seqretry.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:32 -08:00
Heiko Carstens e1c3ad96f6 [PATCH] s390: signal delivery
Always create all signal frames for pending signals before returning to
userspace, not just a single one.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:32 -08:00