This patch adds support for clock synchronization to an external time
reference (ETR). The external time reference sends an oscillator
signal and a synchronization signal every 2^20 microseconds to keep
the TOD clocks of all connected servers in sync. For availability
two ETR units can be connected to a machine. If the clock deviates
for more than the sync-check tolerance all cpus get a machine check
that indicates that the clock is out of sync. For the lovely details
how to get the clock back in sync see the code below.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This provides a noexec protection on s390 hardware. Our hardware does
not have any bits left in the pte for a hw noexec bit, so this is a
different approach using shadow page tables and a special addressing
mode that allows separate address spaces for code and data.
As a special feature of our "secondary-space" addressing mode, separate
page tables can be specified for the translation of data addresses
(storage operands) and instruction addresses. The shadow page table is
used for the instruction addresses and the standard page table for the
data addresses.
The shadow page table is linked to the standard page table by a pointer
in page->lru.next of the struct page corresponding to the page that
contains the standard page table (since page->private is not really
private with the pte_lock and the page table pages are not in the LRU
list).
Depending on the software bits of a pte, it is either inserted into
both page tables or just into the standard (data) page table. Pages of
a vma that does not have the VM_EXEC bit set get mapped only in the
data address space. Any try to execute code on such a page will cause a
page translation exception. The standard reaction to this is a SIGSEGV
with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn)
and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the
kernel to the signal stack frame. Unfortunately, the signal return
mechanism cannot be modified to use an SA_RESTORER because the
exception unwinding code depends on the system call opcode stored
behind the signal stack frame.
This feature requires that user space is executed in secondary-space
mode and the kernel in home-space mode, which means that the addressing
modes need to be switched and that the noexec protection only works
for user space.
After switching the addressing modes, we cannot use the mvcp/mvcs
instructions anymore to copy between kernel and user space. A new
mvcos instruction has been added to the z9 EC/BC hardware which allows
to copy between arbitrary address spaces, but on older hardware the
page tables need to be walked manually.
Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
kretprobe_trampoline_holder() is in kprobes section but used to
register a kprobe in arch_init_kprobes(). Hence register_kprobe()
and therefore arch_init_kprobes() will fail.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of an illegal op the die notifier gets called with DIE_TRAP
instead of DIE_BPT first.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
FCP dump feature detection works only if the sclp command in head.S
was succesful. Since the sclp command is skipped if diag260 works,
we don't have any dump feature detection anymore.
Bug was introduced with d57de5a367.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change the bounce buffer logic of cpcmd. diag8 needs _real_ memory below
2GB. Therefore vmalloced data does not work. As the data might cross a
page boundary, we cannot use virt_to_page either. The solution is to use
virt_to_page only in the check for a bounce buffer.
There was a redundant check for response==NULL. response < 2GB contains
this check as well.
I also removed the rlen==0 check, since rlen=0 and response!=NULL would
be a caller bug and response==NULL is already checked.
Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
setup_memory_end() uses VMALLOC_END instead of VMALLOC_END_INIT to
calculate the maximum supported size of physical memory. Since
VMALLOC_END is zero, this will cause a crash on 31 bit systems.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
72486f1f8f inverts the logic if an
'online' attribute in /sys/devices/system/cpu/cpuX should appear.
So we end up with no hotpluggable cpus at all...
Set the hotpluggable value to one to make sure the online
attribute appears again.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix a memory leak problem in the memory detection routines. A memory leak
of 128k occurs when we have a contiguous memory with mixed access-mode
(read or write) ranges.
Signed-off-by: Hongjie Yang <hongjie@us.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The dump tools expect that the saved prefix register points to the
lowcore of the dump cpu. Since we set the prefix register to 0 during
reipl/dump, we have to save the original prefix register. Before we
start the dump program, we copy the original prefix register to the
designated location in the lowcore.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We use printks after shutting down all other cpus. This is not allowed
and can lead to deadlocks. Therefore the printks have to be removed.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reboot hangs on LPARs without diag308 support. The reason for this is,
that before the reboot is done, the channel subsystem is shut down.
During the reset on each possible subchannel a "store subchannel" is
done. This operation can end in a program check interruption, if the
specified subchannel set is not implemented by the hardware. During
the reset, currently we do not have a program check handler, which
leads to the described kernel bug. We install now a new program check
handler for the reboot code to fix this problem.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Run this:
#!/bin/sh
for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do
echo "De-casting $f..."
perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f
done
And then go through and reinstate those cases where code is casting pointers
to non-pointers.
And then drop a few hunks which conflicted with outstanding work.
Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Karsten Keil <kkeil@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Steven French <sfrench@us.ibm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
[S390] Poison init section before freeing it.
[S390] Use add_active_range() and free_area_init_nodes().
[S390] Virtual memmap for s390.
[S390] Update documentation for dynamic subchannel mapping.
[S390] Use dev->groups for adding/removing the subchannel attribute group.
[S390] Support for disconnected devices reappearing on another subchannel.
[S390] subchannel lock conversion.
[S390] Some preparations for the dynamic subchannel mapping patch.
[S390] runtime switch for qdio performance statistics
[S390] New DASD feature for ERP related logging
[S390] add reset call handler to the ap bus.
[S390] more workqueue fixes.
[S390] workqueue fixes.
[S390] uaccess_pt: add missing down_read() and convert to is_init().
Size zones and holes in an architecture independent manner for s390.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Virtual memmap support for s390. Inspired by the ia64 implementation.
Unlike ia64 we need a mechanism which allows us to dynamically attach
shared memory regions.
These memory regions are accessed via the dcss device driver. dcss
implements the 'direct_access' operation, which requires struct pages
for every single shared page.
Therefore this implementation provides an interface to attach/detach
shared memory:
int add_shared_memory(unsigned long start, unsigned long size);
int remove_shared_memory(unsigned long start, unsigned long size);
The purpose of the add_shared_memory function is to add the given
memory range to the 1:1 mapping and to make sure that the
corresponding range in the vmemmap is backed with physical pages.
It also initialises the new struct pages.
remove_shared_memory in turn only invalidates the page table
entries in the 1:1 mapping. The page tables and the memory used for
struct pages in the vmemmap are currently not freed. They will be
reused when the next segment will be attached.
Given that the maximum size of a shared memory region is 2GB and
in addition all regions must reside below 2GB this is not too much of
a restriction, but there is room for improvement.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When we are unregistering a kprobe-booster, we can't release its
instruction buffer immediately on the preemptive kernel, because some
processes might be preempted on the buffer. The freeze_processes() and
thaw_processes() functions can clean most of processes up from the buffer.
There are still some non-frozen threads who have the PF_NOFREEZE flag. If
those threads are sleeping (not preempted) at the known place outside the
buffer, we can ensure safety of freeing.
However, the processing of this check routine takes a long time. So, this
patch introduces the garbage collection mechanism of insn_slot. It also
introduces the "dirty" flag to free_insn_slot because of efficiency.
The "clean" instruction slots (dirty flag is cleared) are released
immediately. But the "dirty" slots which are used by boosted kprobes, are
marked as garbages. collect_garbage_slots() will be invoked to release
"dirty" slots if there are more than INSNS_PER_PAGE garbage slots or if
there are no unused slots.
Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "bibo,mao" <bibo.mao@intel.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Yumiko Sugita <yumiko.sugita.yf@hitachi.com>
Cc: Satoshi Oshima <soshima@redhat.com>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Define elf_addr_t in linux/elf.h. The size of the type is determined using
ELF_CLASS. This allows us to remove the defines that today are spread all
over .c and .h files.
Signed-off-by: Magnus Damm <magnus@valinux.co.jp>
Cc: Daniel Jacobowitz <drow@false.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
VMALLOC_END on 31bit should be 0x8000000UL instead of 0x7fffffffL.
The page mask which is used to make sure memory_end is on 4MB/2MB
boundary is wrong and not needed. Therefore remove it.
Make sure a vmalloc area does also exist and work on (future)
machines with 4TB and more memory.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Follow i386/x86_64:
lockdep can be used to print held locks when printing a
backtrace. This can be useful when debugging things like
'scheduling while atomic' asserts.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Avoid the tprot loop if diag260 works and reports that there are no
holes in memory. The tprot instruction can lead to a significant delay
in the ipl process if the virtual guest has a lot of memory and the
host is under memory pressure.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Need this at yet another file and don't want to add yet another
extern...
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the memory detection code would ever reach the point where it would
load the wait psw, it would generate a specification exception and the
system would crash at ipl time. This is because of a misaligned wait
psw. It needs to be on a double word boundary instead of a word
boundary.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Let one master cpu kill all other cpus instead of sending an external
interrupt to all other cpus so they can kill themselves.
Simplifies reipl/shutdown functions a lot.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of reipl cpcmd gets called when all other cpus are not running
anymore. To prevent deadlocks change __cpcmd so that it doesn't take
any locks and call cpcmd or __cpcmd, whatever is correct in the current
context.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of re-IPL and diag308 doesn't work we have to reset all devices
manually and wait synchronously that each reset finished.
This patch adds the necessary infrastucture and the first exploiter of it.
Subsystems that need to add a function that needs to be called at re-IPL
may register/unregister this function via
struct reset_call {
struct reset_call *next;
void (*fn)(void);
};
void register_reset_call(struct reset_call *reset);
void unregister_reset_call(struct reset_call *reset);
When the registered function get called the context is:
- all cpus beside the current one are stopped
- all machine checks and interrupts are disabled
- prefixing is disabled
- a default machine check handler is available for use
The registered functions may not take any locks are sleep.
For the common I/O layer part of this patch:
Introduce a reset_call css_reset that does the following:
- clear all subchannels
- perform a rchp on all channel paths and wait for the resulting
machine checks
This replaces the calls to clear_all_subchannels() and
cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now
uses reipl_find_schid() to determine the subchannel id for a given
device id.
Also remove cio_reset_channel_paths() and friends since they are not
needed anymore.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since the diag 308 reipl method is superior to the ccw method, we should
use it whenever it is possible. We can do that, if the user has not
specified a new reipl ccw device and the system has been ipled from
a ccw device.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If reboot fails (e.g. because wrong devno has been specified by the user),
we should just stop all cpus, but should not trigger a kernel panic.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If multiple kernel images are installed on one DASD, the loadparm can be used
to select the boot configuration. This patch introduces the following two new
sysfs attributes:
/sys/firmware/ipl/loadparm: shows loadparm of current system (ro)
/sys/firmware/reipl/ccw/loadparm: loadparm used for next reboot (rw)
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The SALIPL entry point has an needless memory detection routine as we
later check the memory size again. The SALIPL code also uses diagnose
0x060 if we are running under VM, but this diagnose is not compatible
with the 64 bit addressing mode. The solution is to get rid of this
code and rely on the memory detection in the startup code.
Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
setup_lowcore() calls ctl_set_bit() which returns withs interrupts
enabled. The setup arch code is not supposed to enable interrupts that
early. Therefore use the __ctl_set_bit() variant.
This fixes the not working lock dependency validator on non 64 bit
systems.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit 7676bef9c1 breaks DCSS support on
s390. DCSS needs initialized struct pages to work. With the usage of
add_active_range() only the struct pages for physically present pages
are initialized.
This could be fixed if the DCSS driver would initiliaze the struct pages
itself, but this doesn't work too. This is because the mem_map array
does not include holes after the last present memory area and therefore
there is nothing that could be initialized.
To fix this and to avoid some dirty hacks revert this patch for now.
Will be added later when we move to a virtual mem_map.
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
[S390] cio: Make ccw_device_register() static.
[S390] Improve AP bus device removal.
[S390] uaccess error handling.
[S390] cio: css_probe_device() must be called enabled.
[S390] Initialize interval value to 0.
[S390] sys_getcpu compat wrapper.
Add a vmlinux.lds.h helper macro for defining the eight-level initcall table,
teach all the architectures to use it.
This is a prerequisite for a patch which performs initcall synchronisation for
multithreaded-probing.
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
[ Added AVR32 as well ]
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Consider return values for all user space access function and
return -EFAULT on error.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Looking at the new syscall additions, I noticed that
sys_getcpu_wrapper wraps in to sys_tee, in what appears to be
a copy and paste error. Switch it to point to sys_getcpu..
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix the following compile error:
CC init/version.o
LD init/built-in.o
LD .tmp_vmlinux1
arch/s390/kernel/built-in.o(.text+0xdba4): In function `sys32_ipc':
: undefined reference to `compat_sys_semtimedop'
arch/s390/kernel/built-in.o(.text+0xdbee): In function `sys32_ipc':
: undefined reference to `compat_sys_semctl'
arch/s390/kernel/built-in.o(.text+0xdc08): In function `sys32_ipc':
: undefined reference to `compat_sys_msgsnd'
arch/s390/kernel/built-in.o(.text+0xdc30): In function `sys32_ipc':
: undefined reference to `compat_sys_msgrcv'
arch/s390/kernel/built-in.o(.text+0xdc58): In function `sys32_ipc':
: undefined reference to `compat_sys_msgctl'
arch/s390/kernel/built-in.o(.text+0xdc76): In function `sys32_ipc':
: undefined reference to `compat_sys_shmat'
arch/s390/kernel/built-in.o(.text+0xdcb0): In function `sys32_ipc':
: undefined reference to `compat_sys_shmctl'
make: *** [.tmp_vmlinux1] Error 1
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The latest kernel 2.6.19-rc1 triggers a bug in the s390 specific stack
trace code when compiled with gcc 3.4.
This patch fixes the latest lock dependency validator code (2.6.19-rc1)
on s390 gcc 3.4. The variable sp was fixed to r15 (which is the stack
pointer in the s390 abi) and assigned new values to r15. Therefore,
gcc 3.4 assigns a new value to r15 and does not restore it on exit (r15
is supposed to be call save) - the kernel stack is broken. Avoid trouble
by not assigning any new value to sp (r15).
Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the last few places where a pointer to pt_regs gets passed.
Also make sure we call set_irq_regs() before irq_enter() and after
irq_exit(). This doesn't fix anything but makes sure s390 looks the
same like all other architectures.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix too slow clock by using CONFIG_GENERIC_TIME and adding a
clock source for the s390 time-of-day clock. As added benefit
we get rid of the s390 specific definition of do_gettimeofday
and do_settimeofday.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
