Commit Graph

542 Commits

Author SHA1 Message Date
James Morris
ec98ce480a Merge branch 'master' into next
Conflicts:
	fs/nfsd/nfs4recover.c

Manually fixed above to use new creds API functions, e.g.
nfs4_save_creds().

Signed-off-by: James Morris <jmorris@namei.org>
2008-12-04 17:16:36 +11:00
Heiko Carstens
0778dc3a62 [S390] Fix alignment of initial kernel stack.
We need an alignment of 16384 bytes for the initial kernel stack if
the kernel is configured for 16384 bytes stacks but the linker script
currently guarantees only an alignment of 8192 bytes.

So fix this and simply use THREAD_SIZE as alignment value which will
always do the right thing.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-27 11:06:58 +01:00
Christian Borntraeger
8107d8296b [S390] fix/cleanup sched_clock
CONFIG_PRINTK_TIME reveals that sched_clock has a wrong offset during boot:
..
[    0.000000]   Movable zone: 0 pages used for memmap
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 775679
[    0.000000] Kernel command line: dasd=4b6c root=/dev/dasda1 ro noinitrd
[    0.000000] PID hash table entries: 4096 (order: 12, 32768 bytes)
[6920575.975232] console [ttyS0] enabled
[6920575.987586] Dentry cache hash table entries: 524288 (order: 10, 4194304 bytes)
[6920575.991404] Inode-cache hash table entries: 262144 (order: 9, 2097152 bytes)
..

The s390 implementation of sched_clock uses the store clock instruction and
subtracts jiffies_timer_cc.
jiffies_timer_cc is a local variable in arch/s390/kernel/time.c and only used
for sched_clock and monotonic clock. For historical reasons there is an offset
on that value. With todays code this offset is unnecessary. By removing that
offset we can get a sched_clock which returns the nanoseconds after time_init.
This improves CONFIG_PRINTK_TIME.

Since sched_clock is the only user, I have also renamed jiffies_timer_cc to
sched_clock_base_cc. In addition, the local variable init_timer_cc is redundant
and can be romved as well.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-27 11:06:57 +01:00
Martin Schwidefsky
59da21398e [S390] fix system call parameter functions.
syscall_get_nr() currently returns a valid result only if the call
chain of the traced process includes do_syscall_trace_enter(). But
collect_syscall() can be called for any sleeping task, the result of
syscall_get_nr() in general is completely bogus.

To make syscall_get_nr() work for any sleeping task the traps field
in pt_regs is replace with svcnr - the system call number the process
is executing. If svcnr == 0 the process is not on a system call path.

The syscall_get_arguments and syscall_set_arguments use regs->gprs[2]
for the first system call parameter. This is incorrect since gprs[2]
may have been overwritten with the system call number if the call
chain includes do_syscall_trace_enter. Use regs->orig_gprs2 instead.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-27 11:06:56 +01:00
James Morris
f3a5c54701 Merge branch 'master' into next
Conflicts:
	fs/cifs/misc.c

Merge to resolve above, per the patch below.

Signed-off-by: James Morris <jmorris@namei.org>

diff --cc fs/cifs/misc.c
index ec36410,addd1dc..0000000
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@@ -347,13 -338,13 +338,13 @@@ header_assemble(struct smb_hdr *buffer
  		/*  BB Add support for establishing new tCon and SMB Session  */
  		/*      with userid/password pairs found on the smb session   */
  		/*	for other target tcp/ip addresses 		BB    */
 -				if (current->fsuid != treeCon->ses->linux_uid) {
 +				if (current_fsuid() != treeCon->ses->linux_uid) {
  					cFYI(1, ("Multiuser mode and UID "
  						 "did not match tcon uid"));
- 					read_lock(&GlobalSMBSeslock);
- 					list_for_each(temp_item, &GlobalSMBSessionList) {
- 						ses = list_entry(temp_item, struct cifsSesInfo, cifsSessionList);
+ 					read_lock(&cifs_tcp_ses_lock);
+ 					list_for_each(temp_item, &treeCon->ses->server->smb_ses_list) {
+ 						ses = list_entry(temp_item, struct cifsSesInfo, smb_ses_list);
 -						if (ses->linux_uid == current->fsuid) {
 +						if (ses->linux_uid == current_fsuid()) {
  							if (ses->server == treeCon->ses->server) {
  								cFYI(1, ("found matching uid substitute right smb_uid"));
  								buffer->Uid = ses->Suid;
2008-11-18 18:52:37 +11:00
Martin Schwidefsky
d2f019fe40 [S390] fix s390x_newuname
The uname system call for 64 bit compares current->personality without
masking the upper 16 bits. If e.g. READ_IMPLIES_EXEC is set the result
of a uname system call will always be s390x even if the process uses
the s390 personality.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-14 18:18:55 +01:00
Heiko Carstens
74af283102 [S390] cpu topology: fix locking
cpu_coregroup_map used to grab a mutex on s390 since it was only
called from process context.
Since c7c22e4d5c "block: add support
for IO CPU affinity" this is not true anymore.
It now also gets called from softirq context.

To prevent possible deadlocks change this in architecture code and
use a spinlock instead of a mutex.

Cc: stable@kernel.org
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-14 18:18:54 +01:00
Heiko Carstens
50bec4ce5d [S390] ftrace: fix kernel stack backchain walking
With CONFIG_IRQSOFF_TRACER the trace_hardirqs_off() function includes
a call to __builtin_return_address(1). But we calltrace_hardirqs_off()
from early entry code. There we have just a single stack frame.
So this results in a kernel stack backchain walk that would walk beyond
the kernel stack. Following the NULL terminated backchain this results
in a lowcore read access.

To fix this we simply call trace_hardirqs_off_caller() and pass the
current instruction pointer.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-14 18:18:53 +01:00
Heiko Carstens
632448f650 [S390] ftrace: disable tracing on idle psw
Disable tracing on idle psw. Otherwise it would give us huge
preempt off times for idle. Which is rather pointless.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-14 18:18:53 +01:00
Heiko Carstens
af4c68740e [S390] lockdep: fix compile bug
arch/s390/kernel/built-in.o: In function `cleanup_io_leave_insn':
mem_detect.c:(.text+0x10592): undefined reference to `lockdep_sys_exit'

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-14 18:18:53 +01:00
Gerald Schaefer
fb2e7c5e33 [S390] Fix range for add_active_range() in setup_memory()
add_active_range() expects start_pfn + size as end_pfn value, i.e. not
the pfn of the last page frame but the one behind that.
We used the pfn of the last page frame so far, which can lead to a
BUG_ON in move_freepages(), when the kernelcore parameter is specified
(page_zone(start_page) != page_zone(end_page)).

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-14 18:18:51 +01:00
David Howells
b6dff3ec5e CRED: Separate task security context from task_struct
Separate the task security context from task_struct.  At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.

Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.

With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:16 +11:00
Heiko Carstens
da5aae7036 [S390] Fix sysdev class file creation.
Use sysdev_class_create_file() to create create sysdev class attributes
instead of sysfs_create_file(). Using sysfs_create_file() wasn't a very
good idea since the show and store functions have a different amount of
parameters for sysfs files and sysdev class files.
In particular the pointer to the buffer is the last argument and
therefore accesses to random memory regions happened.
Still worked surprisingly well until we got a kernel panic.

Cc: stable@kernel.org
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-28 11:12:03 +01:00
Christoph Hellwig
b418da16dd compat: generic compat get/settimeofday
Nothing arch specific in get/settimeofday.  The details of the timeval
conversion varied a little from arch to arch, but all with the same
results.

Also add an extern declaration for sys_tz to linux/time.h because externs
in .c files are fowned upon.  I'll kill the externs in various other files
in a sparate patch.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net> [ sparc bits ]
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:33 -07:00
Christoph Hellwig
f7a5000f7a compat: move cp_compat_stat to common code
struct stat / compat_stat is the same on all architectures, so
cp_compat_stat should be, too.

Turns out it is, except that various architectures have slightly and some
high2lowuid/high2lowgid or the direct assignment instead of the
SET_UID/SET_GID that expands to the correct one anyway.

This patch replaces the arch-specific cp_compat_stat implementations with
a common one based on the x86-64 one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net> [ sparc bits ]
Acked-by: Kyle McMartin <kyle@mcmartin.ca> [ parisc bits ]
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:33 -07:00
Linus Torvalds
37d9869ed9 Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6: (27 commits)
  [S390] Fix checkstack for s390
  [S390] fix initialization of stp
  [S390] 3215: Remove tasklet.
  [S390] console flush on panic / reboot
  [S390] introduce dirty bit for kvm live migration
  [S390] Add ioctl support for EMC Symmetrix Subsystem Control I/O
  [S390] xpram: per device block request queues.
  [S390] dasd: fix message flood for unsolicited interrupts
  [S390] Move private simple udelay function to arch/s390/lib/delay.c.
  [S390] dcssblk: add >2G DCSSs support and stacked contiguous DCSSs support.
  [S390] ptrace changes
  [S390] s390: use sys_pause for 31bit pause entry point
  [S390] qdio enhanced SIGA (iqdio) support.
  [S390] cio: fix cio_tpi.
  [S390] cio: Correct use of ! and &
  [S390] cio: inline assembly cleanup
  [S390] bus_id -> dev_set_name() for css and ccw busses
  [S390] bus_id ->dev_name() conversions in qdio
  [S390] Use s390_root_dev_* in kvm_virtio.
  [S390] more bus_id -> dev_name conversions
  ...
2008-10-11 08:50:01 -07:00
Martin Schwidefsky
4a672cfa3a [S390] fix initialization of stp
chsc_sstpc returns -EIO on error and 0 on success but stp_reset checks
against 1 instead of 0. chsc_sstpc used to return 1 on success, one
call location has not been updated ..

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10 21:34:02 +02:00
Martin Schwidefsky
753c4dd6a2 [S390] ptrace changes
* System call parameter and result access functions
* Add tracehook calls
* Split syscall_trace into two functions do_syscall_trace_enter and
  do_syscall_trace_exit

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10 21:33:57 +02:00
Christoph Hellwig
d86730bb95 [S390] s390: use sys_pause for 31bit pause entry point
sys32_pause is a useless copy of the generic sys_pause.
(and it's certainly not there for old sparc32 binaries..)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10 21:33:56 +02:00
Ingo Molnar
990d0f2ced Merge branches 'sched/devel', 'sched/cpu-hotplug', 'sched/cpusets' and 'sched/urgent' into sched/core 2008-10-08 11:31:02 +02:00
Heiko Carstens
d3d238c774 [S390] nohz: Fix __udelay.
This fixes a regression that came with 934b2857cc
("[S390] nohz/sclp: disable timer on synchronous waits.").
If udelay() gets called from a disabled context it sets the clock comparator
to a value where it expects the next interrupt. When the interrupt happens
the clock comparator gets not reset and therefore the interrupt condition
doesn't get cleared. The result is an endless timer interrupt loop.

In addition this patch fixes also the following:

rcutorture reveals that our __udelay implementation is still buggy,
since it might schedule tasklets, but prevents their execution:

NOHZ: local_softirq_pending 42
NOHZ: local_softirq_pending 02
NOHZ: local_softirq_pending 142
NOHZ: local_softirq_pending 02

To fix this we make sure that only the clock comparator interrupt
is enabled when the enabled wait psw is loaded.
Also no code gets called anymore which might schedule tasklets.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-03 21:55:54 +02:00
Jarod Wilson
3d6e48f433 [S390] CVE-2008-1514: prevent ptrace padding area read/write in 31-bit mode
When running a 31-bit ptrace, on either an s390 or s390x kernel,
reads and writes into a padding area in struct user_regs_struct32
will result in a kernel panic.

This is also known as CVE-2008-1514.

Test case available here:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/tests/ptrace-tests/tests/user-area-padding.c?cvsroot=systemtap

Steps to reproduce:
1) wget the above
2) gcc -o user-area-padding-31bit user-area-padding.c -Wall -ggdb2 -D_GNU_SOURCE -m31
3) ./user-area-padding-31bit
<panic>

Test status
-----------
Without patch, both s390 and s390x kernels panic. With patch, the test case,
as well as the gdb testsuite, pass without incident, padding area reads
returning zero, writes ignored.

Nb: original version returned -EINVAL on write attempts, which broke the
gdb test and made the test case slightly unhappy, Jan Kratochvil suggested
the change to return 0 on write attempts.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Tested-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-09-09 12:39:06 +02:00
Manfred Spraul
e545a6140b kernel/cpu.c: create a CPU_STARTING cpu_chain notifier
Right now, there is no notifier that is called on a new cpu, before the new
cpu begins processing interrupts/softirqs.
Various kernel function would need that notification, e.g. kvm works around
by calling smp_call_function_single(), rcu polls cpu_online_map.

The patch adds a CPU_STARTING notification. It also adds a helper function
that sends the message to all cpu_chain handlers.

Tested on x86-64.
All other archs are untested. Especially on sparc, I'm not sure if I got
it right.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-08 19:25:24 +02:00
Heiko Carstens
5453c1a575 [S390] Fix linker script.
6360b1fbb4 ("move BUG_TABLE into RODATA")
causes this build bug (binutils 2.18.50.0.8.20080709, gcc 4.3.1):

  AS      .tmp_kallsyms1.o
  LD      .tmp_vmlinux2
  KSYM    .tmp_kallsyms2.S
s390x-4.3.1-nm: .tmp_vmlinux2: File truncated
No valid symbol.
make: *** [.tmp_kallsyms2.S] Error 1

So fix this.

Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-25 18:15:01 +02:00
Heiko Carstens
8853e505a1 [S390] Remove unneeded spinlock initialization.
Remove the now unneeded s390_idle.lock spinlock initialization after
Josef Sipek did it the right way in arch/s390/kernel/process.c.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-21 19:46:39 +02:00
Josef 'Jeff' Sipek
3e972394f9 [S390] Fix uninitialized spinlock use
Ever since commit 43ca5c3a1c ([S390] Convert
monitor calls to function calls.), the kernel refused to IPL with spinlock
debugging enabled.

BUG: spinlock bad magic on CPU#0, swapper/0
 lock: 00000000003a4668, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
CPU: 0 Not tainted 2.6.25 #1
Process swapper (pid: 0, task: 000000000034f958, ksp: 0000000000377d60)
0000000000377ab8 0000000000352628 0000000000377d60 0000000000377d60
       0000000000016af4 00000000fffff7b5 0000000000377d60 0000000000000000
       0000000000000000 0000000000377a18 0000000000000009 0000000000377a18
       0000000000377a78 000000000023c920 0000000000016af4 0000000000377a18
       0000000000000005 0000000000000000 0000000000377b58 0000000000377ab8
Call Trace:
([<0000000000016a60>] show_trace+0xdc/0x108)
 [<0000000000016b4e>] show_stack+0xc2/0xfc
 [<0000000000016c9a>] dump_stack+0xb2/0xc0
 [<0000000000172dd4>]

Signed-off-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-21 19:46:39 +02:00
Heiko Carstens
8f84700325 [S390] stp: fix section mismatch warning.
Fix these two (false positive) warnings by adding an __init annoation:

WARNING: vmlinux.o(.text+0x7e6a): Section mismatch in reference from the function stp_reset() to the function .init.text:__alloc_bootmem()
The function stp_reset() references
the function __init __alloc_bootmem().
This is often because stp_reset lacks a __init
annotation or the annotation of __alloc_bootmem is wrong.

WARNING: vmlinux.o(.text+0x7ece): Section mismatch in reference from the function stp_reset() to the function .init.text:free_bootmem()
The function stp_reset() references
the function __init free_bootmem().
This is often because stp_reset lacks a __init
annotation or the annotation of free_bootmem is wrong.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-01 16:39:34 +02:00
Heiko Carstens
d918fe2bd7 [S390] Remove diag 0x260 call from memory detection.
The result of the diag 0x260 call is not always what one would expect.
So just remove it.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-01 16:39:34 +02:00
Heiko Carstens
519620cc3d [S390] Wire up new syscalls.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-01 16:39:32 +02:00
Michael Holzheu
3a95e8eb34 [S390] ipl: Reboot from alternate device does not work when booting from file
During startup we check if diag308 works using diag 308 subcode 6,
which stores the actual ipl information. This fails with rc = 0x102, if
the system has been ipled from the HMC using load from CD or load from file.
In the case of rc = 0x102 we have to assume that diag 308 is working,
since it still can be used to ipl from an alternative device.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-01 16:39:30 +02:00
Rusty Russell
9b1a4d3837 stop_machine: Wean existing callers off stop_machine_run()
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-28 12:16:31 +10:00
Oleg Nesterov
69b895fd13 S390 topology: don't use kthread() for arch_reinit_sched_domains()
Now that it is safe to use get_online_cpus() we can revert

	[S390] cpu topology: Fix possible deadlock.
	commit: fd781fa25c

and call arch_reinit_sched_domains() directly from topology_work_fn().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Paul Menage <menage@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:40 -07:00
Srinivasa D S
ef53d9c5e4 kprobes: improve kretprobe scalability with hashed locking
Currently list of kretprobe instances are stored in kretprobe object (as
used_instances,free_instances) and in kretprobe hash table.  We have one
global kretprobe lock to serialise the access to these lists.  This causes
only one kretprobe handler to execute at a time.  Hence affects system
performance, particularly on SMP systems and when return probe is set on
lot of functions (like on all systemcalls).

Solution proposed here gives fine-grain locks that performs better on SMP
system compared to present kretprobe implementation.

Solution:

 1) Instead of having one global lock to protect kretprobe instances
    present in kretprobe object and kretprobe hash table.  We will have
    two locks, one lock for protecting kretprobe hash table and another
    lock for kretporbe object.

 2) We hold lock present in kretprobe object while we modify kretprobe
    instance in kretprobe object and we hold per-hash-list lock while
    modifying kretprobe instances present in that hash list.  To prevent
    deadlock, we never grab a per-hash-list lock while holding a kretprobe
    lock.

 3) We can remove used_instances from struct kretprobe, as we can
    track used instances of kretprobe instances using kretprobe hash
    table.

Time duration for kernel compilation ("make -j 8") on a 8-way ppc64 system
with return probes set on all systemcalls looks like this.

cacheline              non-cacheline             Un-patched kernel
aligned patch 	       aligned patch
===============================================================================
real    9m46.784s       9m54.412s                  10m2.450s
user    40m5.715s       40m7.142s                  40m4.273s
sys     2m57.754s       2m58.583s                  3m17.430s
===========================================================

Time duration for kernel compilation ("make -j 8) on the same system, when
kernel is not probed.
=========================
real    9m26.389s
user    40m8.775s
sys     2m7.283s
=========================

Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:30 -07:00
Christian Borntraeger
faeba830b0 s390: use virtio_console for KVM on s390
This patch enables virtio_console as the default console on kvm for
s390. We currently use the same notify hack as lguest for early
console output. I will try to address this for lguest and s390 later.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:07 +10:00
Linus Torvalds
ecc8b655b3 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
  nohz: prevent tick stop outside of the idle loop
2008-07-24 12:55:01 -07:00
Andi Kleen
4a0b2b4dbe sysdev: Pass the attribute to the low level sysdev show/store function
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.

I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.

I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.

Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:55:02 -07:00
Thomas Gleixner
e338125b8a nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-07-19 09:44:33 +02:00
Heiko Carstens
8de2ce86cd [S390] Fix stacktrace compile bug.
Add missing module.h include to fix this:

  CC      arch/s390/kernel/stacktrace.o
arch/s390/kernel/stacktrace.c:84: warning: data definition has no type or storage class
arch/s390/kernel/stacktrace.c:84: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
arch/s390/kernel/stacktrace.c:84: warning: parameter names (without types) in function declaration
arch/s390/kernel/stacktrace.c:97: warning: data definition has no type or storage class
arch/s390/kernel/stacktrace.c:97: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
arch/s390/kernel/stacktrace.c:97: warning: parameter names (without types) in function declaration

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-17 17:22:09 +02:00
Ingo Molnar
f6f88e9bfb generic-ipi: more merge fallout
fix more API change fallout in recently merged upstream changes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 22:08:52 +02:00
Ingo Molnar
1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Linus Torvalds
af5329cdf5 Merge branch 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  generic-ipi: powerpc/generic-ipi tree build failure
  stacktrace: fix build failure on sparc64
  stacktrace: export save_stack_trace[_tsk]
  stacktrace: fix modular build, export print_stack_trace and save_stack_trace
  backtrace: replace timer with tasklet + completions
  stacktrace: add saved stack traces to backtrace self-test
  stacktrace: print_stack_trace() cleanup
  debugging: make stacktrace independent from DEBUG_KERNEL
  stacktrace: don't crash on invalid stack trace structs
2008-07-15 10:31:35 -07:00
Linus Torvalds
d18bb9a548 Merge branch 'core/rodata' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/rodata' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  move BUG_TABLE into RODATA
2008-07-14 15:28:10 -07:00
Heiko Carstens
1d030370f0 [S390] Remove P390 support.
Most likely it is broken anyway because of the changes in memory
detection. Since we can't test it and there are probably better ways
that using a P390 card, remove support for it.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:25 +02:00
Martin Schwidefsky
5532bd0f85 [S390] Cleanup kprobes printk messages.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:24 +02:00
Michael Holzheu
21b21fc4f4 [S390] Cleanup s390 debug feature print messages.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:22 +02:00
Martin Schwidefsky
ca366a329a [S390] Cleanup vtime printk messages.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:18 +02:00
Heiko Carstens
23d1742179 [S390] Move memory detection code to own file.
Move memory detection code to own file and also simplify it.
Also add an interface which can be called at any time to get the
current memory layout. This interface is needed by our kernel
internal system dumper.

Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Cc: Michael Holzheu <holzheu@de.ibm.com>
Cc: Frank Munzert <munzert@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:17 +02:00
Akinobu Mita
0788fea4d5 [S390] s390: use memory_read_from_buffer()
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:16 +02:00
Julia Lawall
402a3998ba [S390] arch/s390: Eliminate NULL test and memset after alloc_bootmem
As noted by Akinobu Mita in patch b1fceac2b9,
alloc_bootmem and related functions never return NULL and always return a
zeroed region of memory.  Thus a NULL test or memset after calls to these
functions is unnecessary.

 arch/s390/kernel/topology.c |    2 --
 1 file changed, 2 deletions(-)

This was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression E;
statement S;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
(
- BUG_ON (E == NULL);
|
- if (E == NULL) S
)

@@
expression E,E1;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
- memset(E,0,E1);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:14 +02:00
Hendrik Brueckner
a0443fbb46 [S390] Extra Kernel Parameters via VMPARM
Now it is possible to specify additional kernel parameters on the IPL
command line using the IPL PARM option.
If the Linux system is already running, the new reipl sysfs attribute
'parm' can be used to change kernel parameters for the next reboot.
Examples:
  IPL    C PARM dasd=1234 root=/dev/dasda1
  IPL 1234 PARM savesys=mylnxnss
  echo "init=/bin/bash" > /sys/firmware/reipl/ccw/parm

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:14 +02:00
Heiko Carstens
773922e1da [S390] idle: remove idle notifier chain.
The idle notifier chain consists of at most one element. So there's
no point in having a notifier chain. Remove it and directly call the
function.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:13 +02:00
Martin Schwidefsky
d2fec59551 [S390] stp support.
Add support for clock synchronization with the server time protocol.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:09 +02:00
Heiko Carstens
761cdf6aac [S390] initrd vs bss section clearing.
In case the initrd is located within the bss section it will be
overwritten when the section is cleared. To prevent this just move
the initrd right behind the bss section if it starts within the
section.
The current code already moves the initrd if the bootmem allocator
bitmap would overwrite it. With this patch we should be safe against
initrd corruptions.

Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:09 +02:00
Martin Schwidefsky
63506c4198 [S390] Introduce user_regset accessors for s390
Add the user_regset definitions for normal and compat processes, replace
the dump_regs core dump cruft with the generic CORE_DUMP_USER_REGSET and
replace binfmt_elf32.c with the generic compat_binfmt_elf.c implementation.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:09 +02:00
Heiko Carstens
b4a33acb69 [S390] Remove ipldelay kernel parameter.
Using the ipldelay kernel parameter leads to a crash at IPL time.
Since this is broken since a long time it looks like nobody is using
it anymore. So remove it instead of fixing it.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:01 +02:00
Ingo Molnar
7b4c9505f2 stacktrace: export save_stack_trace[_tsk]
Andrew Morton reported this against linux-next:

ERROR: ".save_stack_trace" [tests/backtracetest.ko] undefined!

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-03 09:17:55 +02:00
Jens Axboe
15c8b6c1aa on_each_cpu(): kill unused 'retry' parameter
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:38 +02:00
Jens Axboe
8691e5a8f6 smp_call_function: get rid of the unused nonatomic/retry argument
It's never used and the comments refer to nonatomic and retry
interchangably. So get rid of it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:35 +02:00
Ingo Molnar
6d72b7952f Merge branch 'linus' into core/rodata 2008-06-16 11:24:00 +02:00
Segher Boessenkool
24d3e210c1 [S390] Fix build failure in __cpu_up()
The first argument to __ctl_store() should be the array to store
stuff in, not just the first element of that array.  With the
current code in __cpu_up(), mainline GCC dies with an internal
compiler error.  I didn't diagnose that further, but just fixed
the kernel bug.

Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-06-10 10:03:28 +02:00
Martin Schwidefsky
209fb9090f [S390] disassembler: fix idte instruction format.
The correct instruction format of idte is "idte r1,r3,r2" with
r1 at bit 24, r3 at bit 16 and r2 at bit 28.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-30 10:03:36 +02:00
Heiko Carstens
67060d9c1f [S390] Fix section mismatch warnings.
This fixes the last remaining section mismatch warnings in s390
architecture code. It reveals also a real bug introduced by... me
with git commit 2069e978d5
("[S390] sparsemem vmemmap: initialize memmap.")

Calling the generic vmemmap_alloc_block() function to get initialized
memory is a nice idea, however that function is __meminit annotated
and therefore the function might be gone if we try to call it later.
This can happen if a DCSS segment gets added.

So basically revert the patch and clear the memmap explicitly to fix
the original bug.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-30 10:03:34 +02:00
Jan Beulich
6360b1fbb4 move BUG_TABLE into RODATA
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:06:08 +02:00
Al Viro
f52111b154 [PATCH] take init_files to fs/file.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-05-16 17:22:20 -04:00
Heiko Carstens
8dd79cb105 [S390] show_interrupts: prevent cpu hotplug when walking cpu_online_map.
Surround all the code withing show_interrupts() with
get/put_online_cpus() to prevent strange results wrt cpu hotplug.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-15 16:52:41 +02:00
Heiko Carstens
85cb185dad [S390] smp: __smp_call_function_map vs cpu_online_map fix.
Both smp_call_function() and __smp_call_function_map() access
cpu_online_map. Both functions run with preemption disabled which
protects for cpus going offline. However new cpus can be added and
therefore the cpu_online_map can change unexpectedly.
So use the call_lock to protect against changes to the cpu_online_map
in start_secondary() and all smp_call_* functions.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-15 16:52:40 +02:00
Cornelia Huck
5cbbf16a0f [S390] s390dbf: Use const char * for dbf name.
We should use const char * for passing the name of the debug feature
around since it will not be changed.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-15 16:52:39 +02:00
Roland McGrath
b499d76bfd [S390] compat ptrace cleanup
This removes redundant arch code for generic ptrace requests
already handled by ptrace_request and compat_ptrace_request.
It simplifies things to just have the standard entry points,
and use the generic compat_sys_ptrace.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-07 09:23:02 +02:00
Christian Borntraeger
0eaeafa10f [S390] s390-kvm: leave sie context on work. Removes preemption requirement
From: Martin Schwidefsky <schwidefsky@de.ibm.com>

This patch fixes a bug with cpu bound guest on kvm-s390. Sometimes it
was impossible to deliver a signal to a spinning guest. We used
preemption as a circumvention. The preemption notifiers called
vcpu_load, which checked for pending signals and triggered a host
intercept. But even with preemption, a sigkill was not delivered
immediately.

This patch changes the low level host interrupt handler to check for the
SIE  instruction, if TIF_WORK is set. In that case we change the
instruction pointer of the return PSW to rerun the vcpu_run loop. The kvm
code sees an intercept reason 0 if that happens. This patch adds accounting
for these types of intercept as well.

The advantages:
- works with and without preemption
- signals are delivered immediately
- much better host latencies without preemption

Acked-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-07 09:23:01 +02:00
Martin Schwidefsky
2688905e6a [S390] s390: Optimize user and work TIF check
On return from syscall or interrupt, we have to check if we return to
userspace (likely) and if there is work todo (less likely) to decide
if we handle the work. We can optimize this check: we first check for
the less likely work case and then check for userspace.

This patch is also a preparation for an additional patch, that fixes a bug
in KVM dealing with cpu bound guests.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-07 09:23:00 +02:00
Ulrich Drepper
d35c7b0e54 unified (weak) sys_pipe implementation
This replaces the duplicated arch-specific versions of "sys_pipe()" with
one unified implementation.  This removes almost 250 lines of duplicated
code.

It's marked __weak, so that *if* an architecture wants to override the
default implementation it can do so by simply having its own replacement
version, since many architectures use alternate calling conventions for
the 'pipe()' system call for legacy reasons (ie traditional UNIX
implementations often return the two file descriptors in registers)

I still haven't changed the cris version even though Linus says the BKL
isn't needed.  The arch maintainer can easily do it if there are really
no obstacles.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-03 13:50:33 -07:00
Linus Torvalds
d67c6f869c Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [S390] Update default configuration.
  [S390] use generic sys_ptrace
  [S390] Remove self ptrace IEEE_IP hack.
  [S390] Convert to SPARSEMEM & SPARSEMEM_VMEMMAP
  [S390] System z large page support.
  [S390] Convert machine feature detection code to C.
  [S390] vmemmap: use clear_table to initialise page tables.
  [S390] Move stfl to system.h and delete duplicated version.
  [S390] uaccess_mvcos: #ifdef config dependent code.
  [S390] cpu topology: Fix possible deadlock.
  [S390] Add topology_core_siblings to topology.h
  [S390] cio: Make isc handling more robust.
  [S390] remove -traditional
  [S390] Automatically detect added cpus.
  [S390] smp: Fix locking order.
  [S390] Add missing ifndef/define to include/asm-s390/sysinfo.h.
  [S390] Move show_regs to traps.c.
  [S390] cio: Use strict_strtoul() for attributes.
2008-04-30 08:38:30 -07:00
Roland McGrath
02a029b325 signals: s390: renumber TIF_RESTORE_SIGMASK
TIF_RESTORE_SIGMASK no longer needs to be in the _TIF_WORK_* masks.  Those low
bits are scarce, and are all used up now.  Renumber TIF_RESTORE_SIGMASK to
free one up.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:37 -07:00
Martin Schwidefsky
941af343e2 [S390] use generic sys_ptrace
After the PT_IEEE_IP hack has been removed s390 can now use
the common code sys_ptrace function.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:48 +02:00
Martin Schwidefsky
613e1def6b [S390] Remove self ptrace IEEE_IP hack.
The self referential PT_IEEE_IP ptrace peek & poke calls have been
broken for that last 6 years. For peek the code always returns 0
instead of the last ieee fault and for poke the code does nothing.
Since nobody noticed the code seems to be superfluous. So lets
remove it.

Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:48 +02:00
Gerald Schaefer
53492b1de4 [S390] System z large page support.
This adds hugetlbfs support on System z, using both hardware large page
support if available and software large page emulation on older hardware.
Shared (large) page tables are implemented in software emulation mode,
by using page->index of the first tail page from a compound large page
to store page table information.

Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:47 +02:00
Heiko Carstens
2e5061e40a [S390] Convert machine feature detection code to C.
From: Heiko Carstens <heiko.carstens@de.ibm.com>
From: Carsten Otte <cotte@de.ibm.com>

This lets us use defines for the magic bits in machine flags instead
of using plain numbers all over the place.
In addition on newer machines features/facilities are indicated by the
result of the stfl instruction. So we use these bits instead of trying
to execute new instructions and check wether we get an exception or
not.
Also the mvpg instruction is always available when in zArch mode,
whereas the idte instruction is only available in zArch mode. This
results in some minor optimizations.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:47 +02:00
Heiko Carstens
484875b11f [S390] Move stfl to system.h and delete duplicated version.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:46 +02:00
Heiko Carstens
fd781fa25c [S390] cpu topology: Fix possible deadlock.
When we get a notification that cpu topology changed, we schedule a
work struct which just calls arch_reinit_sched_domains. This function
in turn calls get_online_cpus() which results int the lockdep warning
below.

After all it turnded out that it's not legal to call get_online_cpus()
from the context of a multi-threaded work queue.
It could deadlock this way:

process 0 (events/cpu-x):
-> run_workqueue
-> removes my work_struct from the work queue
-> calls work_struct->fn
-> get_online_cpus()
-> locks on cpu_hotplug.lock since process 1 below is doing cpu hotplug

process 1:
-> cpu_down (for cpu-x)
-> cpu_hotplug_begin (holds cpu_hotplug.lock now)
-> cpu-x dead
-> notifier_call_chain with CPU_DEAD
-> cleanup_workqueue_thread
-> flush_cpu_workqueue (succeeds)
-> kthread_stop for events/cpu-x
  -> now kthread_stop waits for my work_struct to complete from within
     process 0. -> dead.

A single threaded workqueue wouldn't have such problems, however there is
no such common queue available and it's not worth to create one for the
very rare calls to arch_reinit_sched_domains.

So we just create a kernel thread from our work struct which calls
arch_reinit_sched_domains and are done with it.

Thanks to Oleg Nesterov and Peter Zijlstra for helping me figuring out
that this isn't a false positive lockdep warning:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.25-03562-g3dc5063-dirty #12
-------------------------------------------------------
events/3/14 is trying to acquire lock:
 (&cpu_hotplug.lock){--..}, at: [<0000000000076094>] get_online_cpus+0x50/0x78

but task is already holding lock:
 (topology_work){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (topology_work){--..}:
       [<000000000006fc74>] __lock_acquire+0x1010/0x111c
       [<000000000006fe40>] lock_acquire+0xc0/0xf8
       [<0000000000059d48>] run_workqueue+0x170/0x278
       [<0000000000059edc>] worker_thread+0x8c/0xf0
       [<000000000005f5bc>] kthread+0x68/0xa0
       [<000000000001a33e>] kernel_thread_starter+0x6/0xc
       [<000000000001a338>] kernel_thread_starter+0x0/0xc

-> #1 (events){--..}:
       [<000000000006fc74>] __lock_acquire+0x1010/0x111c
       [<000000000006fe40>] lock_acquire+0xc0/0xf8
       [<000000000005a23c>] cleanup_workqueue_thread+0x60/0xa8
       [<00000000003b2ab8>] workqueue_cpu_callback+0xbc/0x170
       [<00000000003bba80>] notifier_call_chain+0x5c/0xa4
       [<00000000000655a2>] __raw_notifier_call_chain+0x26/0x38
       [<00000000000655e2>] raw_notifier_call_chain+0x2e/0x40
       [<0000000000075e00>] cpu_down+0x228/0x31c
       [<00000000003b1dd8>] store_online+0x64/0xb8
       [<00000000001e7128>] sysdev_store+0x48/0x58
       [<0000000000121cd2>] sysfs_write_file+0x126/0x1c0
       [<00000000000c1944>] vfs_write+0xb0/0x15c
       [<00000000000c20e6>] sys_write+0x56/0x88
       [<0000000000027a68>] sys32_write+0x34/0x4c
       [<0000000000023f70>] sysc_noemu+0x10/0x16
       [<0000000077f3f186>] 0x77f3f186

-> #0 (&cpu_hotplug.lock){--..}:
       [<000000000006fa84>] __lock_acquire+0xe20/0x111c
       [<000000000006fe40>] lock_acquire+0xc0/0xf8
       [<00000000003b701c>] mutex_lock_nested+0xd0/0x364
       [<0000000000076094>] get_online_cpus+0x50/0x78
       [<000000000003a03e>] arch_reinit_sched_domains+0x26/0x58
       [<000000000002700e>] topology_work_fn+0x26/0x34
       [<0000000000059d4e>] run_workqueue+0x176/0x278
       [<0000000000059edc>] worker_thread+0x8c/0xf0
       [<000000000005f5bc>] kthread+0x68/0xa0
       [<000000000001a33e>] kernel_thread_starter+0x6/0xc
       [<000000000001a338>] kernel_thread_starter+0x0/0xc

other info that might help us debug this:

2 locks held by events/3/14:
 #0:  (events){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278
 #1:  (topology_work){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278

stack backtrace:
CPU: 3 Not tainted 2.6.25-03562-g3dc5063-dirty #12
Process events/3 (pid: 14, task: 000000002fb04038, ksp: 000000002fb0bd70)
0400000000000000 000000002fb0ba40 0000000000000002 0000000000000000
       000000002fb0bae0 000000002fb0ba58 000000002fb0ba58 0000000000016488
       0000000000000000 000000002fb0bd70 0000000000000000 0000000000000000
       000000002fb0ba40 000000000000000c 000000002fb0ba40 000000002fb0bab0
       00000000003c99e0 0000000000016488 000000002fb0ba40 000000002fb0ba90
Call Trace:
([<00000000000163fc>] show_trace+0x138/0x158)
 [<00000000000164e2>] show_stack+0xc6/0xf8
 [<0000000000016624>] dump_stack+0xb0/0xc0
 [<000000000006cd36>] print_circular_bug_tail+0xa2/0xb4
 [<000000000006fa84>] __lock_acquire+0xe20/0x111c
 [<000000000006fe40>] lock_acquire+0xc0/0xf8
 [<00000000003b701c>] mutex_lock_nested+0xd0/0x364
 [<0000000000076094>] get_online_cpus+0x50/0x78
 [<000000000003a03e>] arch_reinit_sched_domains+0x26/0x58
 [<000000000002700e>] topology_work_fn+0x26/0x34
 [<0000000000059d4e>] run_workqueue+0x176/0x278
 [<0000000000059edc>] worker_thread+0x8c/0xf0
 [<000000000005f5bc>] kthread+0x68/0xa0
 [<000000000001a33e>] kernel_thread_starter+0x6/0xc
 [<000000000001a338>] kernel_thread_starter+0x0/0xc
INFO: lockdep is turned off.

Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:45 +02:00
Heiko Carstens
d00aa4e7d0 [S390] Add topology_core_siblings to topology.h
This exposes the core siblings to user space via sysfs.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-30 13:38:45 +02:00
Mathieu Desnoyers
47494f6a84 [S390] remove -traditional
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:44 +02:00
Heiko Carstens
1e489518da [S390] Automatically detect added cpus.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:44 +02:00
Heiko Carstens
0b18d318b8 [S390] smp: Fix locking order.
On some smp sysfs store attributes get_online_cpus() may block on
cpu_hotplug.lock, but we hold already smp_cpu_state_mutex. Since the
locking order on cpu hotplug via arch_update_cpu_topology is inverse
this might lead to deadlocks.
So make sure locking order is always the same.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:44 +02:00
Heiko Carstens
4e83be7b24 [S390] Move show_regs to traps.c.
This is where it should be and we can get rid of some externs
and a static inline function.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:43 +02:00
Christoph Lameter
4ca4d7bf7a s390: use kbuild.h instead of defining macros in asm-offsets.c
New version that does not preserve the marker. Arch maintainers indicate
that the marker functionality is is not needed anymore.

Note you may simplify the s390 asm-offsets.c code further if you use the
OFFSET() macro instead of the DEFINE. See kbuild.h

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:30 -07:00
Christoph Lameter
7a88d7a8f4 s390: use kbuild.h instead of defining macros in asm-offsets.c
s390 has a strange marker in DEFINE.  Undefine the DEFINE from kbuild.h and
define it the way s390 wants it to preserve things as they were.

May be good if the arch maintainer could go over this and check if this
workaround is really necessary.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:30 -07:00
Adrian Bunk
eb0f1c442d proper __do_softirq() prototype
Add a proper prototype for __do_softirq() in include/linux/interrupt.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:02 -07:00
Carsten Otte
fa5877439d s390: KVM guest: detect when running on kvm
This patch adds functionality to detect if the kernel runs under the KVM
hypervisor. A macro MACHINE_IS_KVM is exported for device drivers. This
allows drivers to skip device detection if the systems runs non-virtualized.
We also define a preferred console to avoid having the ttyS0, which is a line
mode only console.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:00:50 +03:00
Heiko Carstens
b0c632db63 KVM: s390: arch backend for the kvm kernel module
This patch contains the port of Qumranet's kvm kernel module to IBM zSeries
 (aka s390x, mainframe) architecture. It uses the mainframe's virtualization
instruction SIE to run virtual machines with up to 64 virtual CPUs each.
This port is only usable on 64bit host kernels, and can only run 64bit guest
kernels. However, running 31bit applications in guest userspace is possible.

The following source files are introduced by this patch
arch/s390/kvm/kvm-s390.c    similar to arch/x86/kvm/x86.c, this implements all
                            arch callbacks for kvm. __vcpu_run calls back into
                            sie64a to enter the guest machine context
arch/s390/kvm/sie64a.S      assembler function sie64a, which enters guest
                            context via SIE, and switches world before and after                            that
include/asm-s390/kvm_host.h contains all vital data structures needed to run
                            virtual machines on the mainframe
include/asm-s390/kvm.h      defines kvm_regs and friends for user access to
                            guest register content
arch/s390/kvm/gaccess.h     functions similar to uaccess to access guest memory
arch/s390/kvm/kvm-s390.h    header file for kvm-s390 internals, extended by
                            later patches

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:00:42 +03:00
Carsten Otte
402b08622d s390: KVM preparation: provide hook to enable pgstes in user pagetable
The SIE instruction on s390 uses the 2nd half of the page table page to
virtualize the storage keys of a guest. This patch offers the s390_enable_sie
function, which reorganizes the page tables of a single-threaded process to
reserve space in the page table:
s390_enable_sie makes sure that the process is single threaded and then uses
dup_mm to create a new mm with reorganized page tables. The old mm is freed
and the process has now a page status extended field after every page table.

Code that wants to exploit pgstes should SELECT CONFIG_PGSTE.

This patch has a small common code hit, namely making dup_mm non-static.

Edit (Carsten): I've modified Martin's patch, following Jeremy Fitzhardinge's
review feedback. Now we do have the prototype for dup_mm in
include/linux/sched.h. Following Martin's suggestion, s390_enable_sie() does now
call task_lock() to prevent race against ptrace modification of mm_users.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:00:40 +03:00
Matthew Wilcox
950e4da324 arch: Remove unnecessary inclusions of asm/semaphore.h
None of these files use any of the functionality promised by
asm/semaphore.h.  It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-18 22:14:49 -04:00
Linus Torvalds
d7bb545d86 Merge branch 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc:
  Remove DEBUG_SEMAPHORE from Kconfig
  Improve semaphore documentation
  Simplify semaphore implementation
  Add down_timeout and change ACPI to use it
  Introduce down_killable()
  Generic semaphore implementation
  Add semaphore.h to kernel_lock.c
  Fix quota.h includes
2008-04-18 08:25:29 -07:00
Matthew Wilcox
64ac24e738 Generic semaphore implementation
Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility.  Thanks to Peter Zijlstra for fixing the lockdep
warning.  Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 10:42:34 -04:00
Christian Borntraeger
9e74a6b898 [S390] kernel: show last breaking-event-address on oops
Newer s390 models have a breaking-event-address-recording register.
Each time an instruction causes a break in the sequential instruction
execution, the address is saved in that hardware register. On a program
interrupt the address is copied to the lowcore address 272-279, which
makes it software accessible.

This patch changes the program check handler and the stack overflow
checker to copy the value into the pt_regs argument.
The oops output is enhanced to show the last known breaking address.
It might give additional information if the stack trace is corrupted.

The feature is only available on 64 bit.

The new oops output looks like:

[---------snip----------]
Modules linked in: vmcp sunrpc qeth_l2 dm_mod qeth ccwgroup
CPU: 2 Not tainted 2.6.24zlive-host #8
Process modprobe (pid: 4788, task: 00000000bf3d8718, ksp: 00000000b2b0b8e0)
Krnl PSW : 0704200180000000 000003e000020028 (vmcp_init+0x28/0xe4 [vmcp])
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
Krnl GPRS: 0000000004000002 000003e000020000 0000000000000000 0000000000000001
           000000000015734c ffffffffffffffff 000003e0000b3b00 0000000000000000
           000003e00007ca30 00000000b5bb5d40 00000000b5bb5800 000003e0000b3b00
           000003e0000a2000 00000000003ecf50 00000000b2b0bd50 00000000b2b0bcb0
Krnl Code: 000003e000020018: c0c000040ff4       larl    %r12,3e0000a2000
           000003e00002001e: e3e0f0000024       stg     %r14,0(%r15)
           000003e000020024: a7f40001           brc     15,3e000020026
          >000003e000020028: e310c0100004       lg      %r1,16(%r12)
           000003e00002002e: c020000413dc       larl    %r2,3e0000a27e6
           000003e000020034: c0a00004aee6       larl    %r10,3e0000b5e00
           000003e00002003a: a7490001           lghi    %r4,1
           000003e00002003e: a75900f0           lghi    %r5,240
Call Trace:
([<000000000014b300>] blocking_notifier_call_chain+0x2c/0x40)
 [<000000000015735c>] sys_init_module+0x19d8/0x1b08
 [<0000000000110afc>] sysc_noemu+0x10/0x16
 [<000002000011cda2>] 0x2000011cda2
Last Breaking-Event-Address:
 [<000003e000020024>] vmcp_init+0x24/0xe4 [vmcp]
[---------snip----------]

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:07 +02:00
Heiko Carstens
a806170e29 [S390] Fix a lot of sparse warnings.
Most noteable part of this commit is the new local header file entry.h
which contains all the function declarations of functions that get only
called from asm code or are arch internal. That way we can avoid extern
declarations in C files.
This is more or less the same that was done for sparc64.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:06 +02:00
Heiko Carstens
5a62b19219 [S390] Convert s390 to GENERIC_CLOCKEVENTS.
This way we get rid of s390's NO_IDLE_HZ and use the generic dynticks
variant instead. In addition we get high resolution timers for free.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:05 +02:00
Heiko Carstens
43ca5c3a1c [S390] Convert monitor calls to function calls.
Remove the program check generating monitor calls and use function
calls instead. Theres is no real advantage in using monitor calls,
but they do make debugging harder, because of all the program checks
it generates.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:05 +02:00
Michael Holzheu
9637c3f318 [S390] Add debug_register_mode() function to debug feature API
The new function supports setting of permissions for the debugfs files
created by the debug feature. In addition to that, the function provides
uid and gid as parameters for future use. Currently only root is allowed
for uid and gid.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:03 +02:00
Jan Glauber
c0015f91d8 [S390] switch sched_clock to store-clock-extended.
Add get_clock_xt to read an 8 byte clock value using store clock
extended (STCKE) and use get_clock_xt for sched_clock. STCKE should
be faster than STCK on newer machines.

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>
2008-04-17 07:47:02 +02:00
Heiko Carstens
c10fde0d9e [S390] Vertical cpu management.
If vertical cpu polarization is active then the hypervisor will
dispatch certain cpus for a longer time than other cpus for maximum
performance. For example if a guest would have three virtual cpus,
each of them with a share of 33 percent, then in case of vertical
cpu polarization all of the processing time would be combined to a
single cpu which would run all the time, while the other two cpus
would get nearly no cpu time.

There are three different types of vertical cpus: high, medium and
low. Low cpus hardly get any real cpu time, while high cpus get a
full real cpu. Medium cpus get something in between.

In order to switch between the two possible modes (default is
horizontal) a 0 for horizontal polarization or a 1 for vertical
polarization must be written to the dispatching sysfs attribute:

/sys/devices/system/cpu/dispatching

The polarization of each single cpu can be figured out by the
polarization sysfs attribute of each cpu:

/sys/devices/system/cpu/cpuX/polarization

horizontal, vertical:high, vertical:medium, vertical:low or unknown.

When switching polarization the polarization attribute may contain
the value unknown until the configuration change is done and the
kernel has figured out the new polarization of each cpu.

Note that running a system with different types of vertical cpus may
result in significant performance regressions. If possible only one
type of vertical cpus should be used. All other cpus should be
offlined.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:01 +02:00