Quieten some of the debug ram config output. we already print out available
memory at KERN_INFO level.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
No need to write out what idle loop is used on every boot.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Move time_init console output to KERN_DEBUG prink level. No need to
print it at every boot.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cleanup patch which removes the io_page_mask. It fixes the reset on
some e1000 devices which is needed for clean kexec reboots. The legacy
devices which broke with this patch (parallel port and PC speaker) have
now been fixed in Linus' tree.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In some crash scenarios, the kexec CPU is not responding to an IPI sent by
secondary CPU after init thread is forked, causing the system to drop into
xmon during kdump boot. This problem can be reproduced each time when the
debugger is enabled and soft-reset is used to invoke kdump boot. The first
CPU sends an IPI - setting the IPI priority for all secondary cpus
(xics_cause_ipi()). But some CPUs will enter into the xmon via soft-reset,
i.e, not executing xics_ipi_action(). Hence, IPI is not cleared. When
exited from the debugger, one of these CPUs could become the primary kexec
CPU. Since the IPI is not cleared, causing this issue in kdump boot. This
patch clears and EOI IPI for kexec CPU as well before the kdump boot
started.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We've seen several bugs caused by interrupt weirdness in the kdump kernel.
Panicking from an interrupt handler means we fail to EOI the interrupt, and
so the second kernel never gets that interrupt ever again. We also see hangs
on JS20 where we take interrupts in the second kernel early during boot.
This patch fixes both those problems, and although it adds more code to the
crash path I think it is the best solution.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Every time a new syscall gets added, a BUILD_BUG_ON in
arch/powerpc/platforms/cell/spu_callbacks.c gets triggered.
Since the addition of a new syscall is rather harmless,
the error should just be removed.
While we're here, add sys_tee to the list and add a comment
to systbl.S to remind people that there is another list
on powerpc.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The new i2c implementation for PowerMac has a regression that causes the
hardware to go out of state when probing non-existent devices. While
fixing that, I also found & fixed a couple of other corner cases. This
fixes booting with a pbbuttons version that scans the i2c bus for an LMU
controller among others. Tested on a dual G5 with thermal control (which
has heavy i2c activity) with no problem so far.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Turn on the DART already at 1GB. This is needed because of crippled
devices in some systems, i.e. Airport Extreme cards, only supporting
30-bit DMA addresses.
Otherwise, users with between 1 and 2GB of memory will need to manually
enable it with iommu=force, and that's no good.
Some simple performance tests show that there's a slight impact of
enabling DART, but it's in the 1-3% range (kernel build with disk I/O
as well as over NFS).
iommu=off can still be used for those who don't want to deal with the
overhead (and don't need it for any devices).
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Some devices don't support full 32-bit DMA address space, which we currently
assume. Add the required mask-passing to the IOMMU allocators.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Andrew Morton pointed out that compiler might not inline the functions
marked for inline in kprobes. There-by allowing the insertion of probes
on these kprobes routines, which might cause recursion.
This patch removes all such inline and adds them to kprobes section
there by disallowing probes on all such routines. Some of the routines
can even still be inlined, since these routines gets executed after the
kprobes had done necessay setup for reentrancy.
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc-merge:
powerpc: Use correct sequence for putting CPU into nap mode
[PATCH] spufs: fix context-switch decrementer code
[PATCH] powerpc32: Set cpu explicitly in kernel compiles
[PATCH] powerpc/pseries: bugfix: balance calls to pci_device_put
[PATCH] powerpc: Fix machine detection in prom_init.c
[PATCH] ppc32: Fix string comparing in platform_notify_map
[PATCH] powerpc: Avoid __initcall warnings
[PATCH] powerpc: Ensure runlatch is off in the idle loop
powerpc: Fix CHRP booting - needs a define_machine call
powerpc: iSeries has only 256 IRQs
We weren't using the recommended sequence for putting the CPU into
nap mode. When I changed the idle loop, for some reason 7447A cpus
started hanging when we put them into nap mode. Changing to the
recommended sequence fixes that.
The complexity here is that the recommended sequence is a loop that
keeps putting the cpu back into nap mode. Clearly we need some way
to break out of the loop when an interrupt (external interrupt,
decrementer, performance monitor) occurs. Here we use a bit in
the thread_info struct to indicate that we need this, and the exception
entry code notices this and arranges for the exception to return
to the value in the link register, thus breaking out of the loop.
We use a new `local_flags' field in the thread_info which we can
alter without needing to use an atomic update sequence.
The PPC970 has the same recommended sequence, so we do the same thing
there too.
This also fixes a bug in the kernel stack overflow handling code on
32-bit, since it was causing a value that we needed in a register to
get trashed.
Signed-off-by: Paul Mackerras <paulus@samba.org>
We found that when the 'decrementer' is saved, the PPE saves the current
time 'csa->suspend_time'. When restoring the 'decrementer', (Step 34)
decrementer seems to be adjusted with the number of cycles th= at a spu
thread has not been running.
In that code it is missing a substract ('-') because 'delta_time' is
assigned a not substracted(see bellow).
Acked-by: Mark Nutter <mnutter@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Compile the 32bit kernel with -mcpu=powerpc. This reduces the imagesize
when a compiler is used that defaults to -mtune=power4. It inserts lots
of nops to please the 64bit cpu instruction scheduling. But all these nops
are not needed for 32bit kernels.
Example with SLES10 gcc 4.1.0 and arch/powerpc/configs/pmac32_defconfig:
vmlinux vmlinux.strip vmlinux.gz
-O2 4980515 4187528 1846829
-Os 4618801 3827084 1673333
-O2 -mcpu=powerpc 4738851 3945868 1816253
-Os -mcpu=powerpc 4532785 3741068 1664688
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Repeated calls to eeh_remove_device() can result in multiple
(and thus unbalanced) calls to pci_dev_put(). Make sure the
pci_device_put() is called only once (since there was only
one call to the matching pci_device_get()).
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In e8222502ee the detection of machine types
in prom_init broke for some machines. We should be checking /device_type
instead of /model. This should make Power3 and Power4 boot again. Haven't
been able to test this. We also need to relocate before comparing.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fix __initcall return in proc_rtas_init and rtas_init.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Since external and decrementer interrupts set the runlatch on, we need
to ensure its set off again in the idle loop. At the moment we dont turn
it off in the inner loop.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Basically an in-kernel implementation of tee, which uses splice and the
pipe buffers as an intelligent way to pass data around by reference.
Where the user space tee consumes the input and produces a stdout and
file output, this syscall merely duplicates the data inside a pipe to
another pipe. No data is copied, the output just grabs a reference to the
input pipe data.
Signed-off-by: Jens Axboe <axboe@suse.de>
Current implementations define NODES_SHIFT in include/asm-xxx/numnodes.h for
each arch. Its definition is sometimes configurable. Indeed, ia64 defines 5
NODES_SHIFT values in the current git tree. But it looks a bit messy.
SGI-SN2(ia64) system requires 1024 nodes, and the number of nodes already has
been changeable by config. Suitable node's number may be changed in the
future even if it is other architecture. So, I wrote configurable node's
number.
This patch set defines just default value for each arch which needs multi
nodes except ia64. But, it is easy to change to configurable if necessary.
On ia64 the number of nodes can be already configured in generic ia64 and SN2
config. But, NODES_SHIFT is defined for DIG64 and HP'S machine too. So, I
changed it so that all platforms can be configured via CONFIG_NODES_SHIFT. It
would be simpler.
See also: http://marc.theaimsgroup.com/?l=linux-kernel&m=114358010523896&w=2
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The patch removing _machine and converting platforms over to use
define_machine wasn't complete as far as CHRP was concerned. This
adds the define_machine call for CHRP and gets it booting again.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds support for 85xx CDS support to arch/powerpc
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The iSeries Hypervisor only allows us to specify IRQ numbers up to 255 (it
has a u8 field to pass it in). This patch allows platforms to specify a
maximum to the virtual IRQ numbers we will use and has iSeries set that
to 255. If not set, the maximum is NR_IRQS - 1 (as before).
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Since the powerpc 64k pages patch went in, systems that have SLBs
(like Power4 iSeries) needed to have slb_initialize called to set up
some variables for the SLB miss handler. This was not being called
on the boot processor on iSeries, so on single cpu iSeries machines,
we would get apparent memory curruption as soon as we entered user mode.
This patch fixes that by calling slb_initialize on the boot cpu if the
processor has an SLB.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Missing include for __NR_syscalls, and missing sys_splice() that
causes build-time failure due to compile-time bounds check on
spu_syscall_table.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch removes unnecessary exports, marks functions as static when
possible, and simplifies some list-related code.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes several problems with the lparcfg code. In case
someone gets a sense of deja-vu, part of this was submitted last Sep, I
thought the changes went in, but either got backed out, or just got
lost.
First, change the local_buffer declaration to be unsigned char *. We
had a bad-math problem in a 2.4 tree which was built with a
"-fsigned-char" parm. I dont believe we ever build with that parm
now-a-days, but to be safe, I'd prefer the declaration be explicit.
Second, fix a bad math calculation for splpar_strlen.
Third, on the rtas_call for get-system-parameter, pass in
RTAS_DATA_BUF_SIZE for the rtas_data_buf size, instead of letting random
data determine the size. Until recently, we've had a sufficiently
large 'random data' value get passed in, so the function just happens to
have worked OK. Now it's getting passed a '0', which causes the
rtas_call to return success, but no data shows up in the buffer.
(oops!). This was found by the LTC test org.
This is in a branch of code that only gets run on SPLPAR systems.
Tested on power5 Lpar.
Signed-off-by: Will Schmidt <willschm@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The recent patch to print device names in EEH reset messages
was lacking ... this patch works better.
Signed-off-by: Linas Vepstas <linas@linas.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This extends the HCALL interface for InfiniBand usage. I've
made the patch against the linux-2.6 git tree and Segher's patch:
[PATCH] Change H_StudlyCaps to H_SHOUTING_CAPS
We moved this into the common powerpc code based on comments we
got after posting the first eHCA InfiniBand device driver patch.
Signed-off-by: Heiko j Schick <schickhj@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Also cleans up some nearby whitespace problems.
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The current code prints an ambiguous message if the recovery
of a failed PCI device fails. Give this special case its own
unique message.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This forces the processing of EEH PCI events to be serialized,
using a very simple mutex lock. This serialization is required to
avoid races involving additional PCI device failures that may occur
during the recovery phase of a previous failure.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The only user of get_wchan is the proc fs - and proc can't be built modular.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The boot cmdline is parsed in parse_early_param() and
parse_args(,unknown_bootoption).
And __setup() is used in obsolete_checksetup().
start_kernel()
-> parse_args()
-> unknown_bootoption()
-> obsolete_checksetup()
If __setup()'s callback (->setup_func()) returns 1 in
obsolete_checksetup(), obsolete_checksetup() thinks a parameter was
handled.
If ->setup_func() returns 0, obsolete_checksetup() tries other
->setup_func(). If all ->setup_func() that matched a parameter returns 0,
a parameter is seted to argv_init[].
Then, when runing /sbin/init or init=app, argv_init[] is passed to the app.
If the app doesn't ignore those arguments, it will warning and exit.
This patch fixes a wrong usage of it, however fixes obvious one only.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mark unwind info for signal trampolines using the new S augmentation flag
introduced in: http://gcc.gnu.org/PR26208.
GCC 4.2 (or patched earlier GCC) will be able to special case unwinding
through frames right above signal trampolines. As the augmentations start
with z flag and S is at the very end of the augmentation string, older GCCs
will just skip the S flag as unknown (that's why an augmentation flag was
chosen over say a new CFA opcode).
Signed-off-by: Jakub Jelinek <jakub@redhat.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Removed platform_init usage on 83xx and 85xx and use define_machine and
probe(). For now we always return true in the problem since you can only
build for one specific board at a time. This is an artificial constraint.
When we get ride of it we will need to update the Kconfig's for these
sub-arch's and make the board's probe() functions actually do something.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Remove oprofile spinlock backtrace code now we have proper calltrace
support. Also make MMCRA sihv and sipr bits a variable since they may
change in future cpus. Finally, MMCRA should be a 64bit quantity.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add calltrace support for other powerpc cpus. Tested on 7450.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add oprofile calltrace support to powerpc. Disable spinlock backtracing
now we can use calltrace info.
(Updated to work on both 32bit and 64bit by me).
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fix 44x and BookE page fault handler to correctly lock PTE before
trying to pte_update() it, otherwise this PTE might be swapped out
after pte_present() check but before pte_uptdate() call, resulting in
corrupted PTE. This can happen with enabled preemption and low memory
condition.
Signed-off-by: Eugene Surovegin <ebs@ebshome.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Mark the f_ops members of inodes as const, as well as fix the
ripple-through this causes by places that copy this f_ops and then "do
stuff" with it.
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This removes statically assigned platform numbers and reworks the
powerpc platform probe code to use a better mechanism. With this,
board support files can simply declare a new machine type with a
macro, and implement a probe() function that uses the flattened
device-tree to detect if they apply for a given machine.
We now have a machine_is() macro that replaces the comparisons of
_machine with the various PLATFORM_* constants. This commit also
changes various drivers to use the new macro instead of looking at
_machine.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We used to assume that a DMA mapping request with a NULL dev was for
ISA DMA. This assumption was broken at some point. Now we explicitly
pass the detected ISA PCI device in the floppy setup.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Non zero initcalls (except for -ENODEV) have started warning at boot.
Fix smt_setup and init_ras_IRQ.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A bug in the RTAS services incorrectly interprets some bits in the CR
when called from the OS. Specifically, bits in CR4. The result could
be a firmware crash that also takes down the partition. A firmware
fix is in the works. We have seen this situation when performing DLPAR
operations. As a temporary workaround, clear the CR in enter_rtas().
Note that enter_rtas() will not set any bits in CR4 before calling RTAS.
Also note that the 32 bit version of enter_rtas() should have the same
work around even though the chances of hitting the bug are much smaller
due to the lack of DLPAR on 32 bit kernels. However, my assembly skills
are a bit rusty and the 32 bit code doesn't seem to follow the conventions
for where things should be saved. In addition, I don't have a system
to test 32 bit kernels. Help creating and at least touch testing the
same workaround for 32 bit would be appreciated.
Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
spufs_init and spufs_exit should be marked correctly so
they can be removed when not needed.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These are some updates from both Ryan and Arnd for the hvc_console
driver:
The main point is to enable the inclusion of a console driver
for rtas, which is currrently needed for the cell platform.
Also shuffle around some data-type declarations and moves some
functions out of include/asm-ppc64/hvconsole.h and into a new
drivers/char/hvc_console.h file.
Signed-off-by: "Ryan S. Arnold" <rsa@us.ibm.com>
Signed-off-by: Arnd Bergmann <abergman@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
*) When setting a sighandler using sigaction() call, if the flag
SA_ONSTACK is set and no alternate stack is provided via sigaltstack(),
the kernel still try to install the alternate stack. This behavior is
the opposite of the one which is documented in Single Unix
Specifications V3.
*) Also when setting an alternate stack using sigaltstack() with the
flag SS_DISABLE, the kernel try to install the alternate stack on
signal delivery.
These two use cases makes the process crash at signal delivery.
This fixes it.
Signed-off-by: Laurent Meyer <meyerlau@fr.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We need to export ppc64_firmware_features for modules. Before we do that
I think we should probably rename it to powerpc_firmware_features.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When we build for the MPC8540 ADS produce a uImage by default.
Updated the defconfig to reflect this as well.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Towards the goal of having arch/powerpc not build anything over in arch/ppc
move math-emu over. Also, killed some references to arch/ppc/ in the
arch/powerpc Makefile which should belong in drivers/ when the particular
sub-arch's move over to arch/powerpc.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Export validate_sp so we can use it in the oprofile calltrace code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a mistake I made when editing these functions - when I
took out the interrupt disabling code (because interrupts are now
disabled by the caller) I left the register that is used for the MSR
value to be used during doze/nap uninitialized. This fixes it.
Also updated some of the comments in idle_power4.S and removed some
code that was copied over from idle_6xx.S but is no longer relevant
(we don't ever clear the CPU_FTR_CAN_NAP bit at runtime for POWER4).
Signed-off-by: Paul Mackerras <paulus@samba.org>
The kernel's implementation of notifier chains is unsafe. There is no
protection against entries being added to or removed from a chain while the
chain is in use. The issues were discussed in this thread:
http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2
We noticed that notifier chains in the kernel fall into two basic usage
classes:
"Blocking" chains are always called from a process context
and the callout routines are allowed to sleep;
"Atomic" chains can be called from an atomic context and
the callout routines are not allowed to sleep.
We decided to codify this distinction and make it part of the API. Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name). New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain. The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.
With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed. For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections. (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)
There are some limitations, which should not be too hard to live with. For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem. Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain. (This did happen in a couple of places and the code
had to be changed to avoid it.)
Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization. Instead we use RCU. The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.
Here is the list of chains that we adjusted and their classifications. None
of them use the raw API, so for the moment it is only a placeholder.
ATOMIC CHAINS
-------------
arch/i386/kernel/traps.c: i386die_chain
arch/ia64/kernel/traps.c: ia64die_chain
arch/powerpc/kernel/traps.c: powerpc_die_chain
arch/sparc64/kernel/traps.c: sparc64die_chain
arch/x86_64/kernel/traps.c: die_chain
drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list
kernel/panic.c: panic_notifier_list
kernel/profile.c: task_free_notifier
net/bluetooth/hci_core.c: hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain
net/ipv6/addrconf.c: inet6addr_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain
net/netlink/af_netlink.c: netlink_chain
BLOCKING CHAINS
---------------
arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain
arch/s390/kernel/process.c: idle_chain
arch/x86_64/kernel/process.c idle_notifier
drivers/base/memory.c: memory_chain
drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list
drivers/macintosh/adb.c: adb_client_list
drivers/macintosh/via-pmu.c sleep_notifier_list
drivers/macintosh/via-pmu68k.c sleep_notifier_list
drivers/macintosh/windfarm_core.c wf_client_list
drivers/usb/core/notify.c usb_notifier_list
drivers/video/fbmem.c fb_notifier_list
kernel/cpu.c cpu_chain
kernel/module.c module_notify_list
kernel/profile.c munmap_notifier
kernel/profile.c task_exit_notifier
kernel/sys.c reboot_notifier_list
net/core/dev.c netdev_chain
net/decnet/dn_dev.c: dnaddr_chain
net/ipv4/devinet.c: inetaddr_chain
It's possible that some of these classifications are wrong. If they are,
please let us know or submit a patch to fix them. Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)
The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.
[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On CHRP machines we are supposed to call into firmware (RTAS)
periodically, to give it a chance to check for errors and other
events. Under ppc we had some special code in timer_interrupt
to do this, but that didn't get transferred over to arch/powerpc.
Instead, we use an array of timer_list structs, one per CPU,
and use add_timer_on to make sure each one gets called on the
appropriate CPU.
With this we can remove the heartbeat_* elements of the ppc_md
struct.
Signed-off-by: Paul Mackerras <paulus@samba.org>
All of the things needed for 32-bit ARCH=powerpc builds have now
moved to arch/powerpc/kernel, so we don't need to go down into
arch/ppc/kernel any more, and we can remove the CONFIG_PPC_MERGE
conditional from arch/ppc/kernel/Makefile.
There were two files still referenced in the merge section of
arch/ppc/kernel/Makefile: ppc-stub.o, depending on CONFIG_KGDB,
and dma-mapping.o, depending on CONFIG_NOT_COHERENT_CACHE. None
of the platforms currently in ARCH=powerpc have caches that
aren't coherent with DMA, but when we do get one we'll move
dma-mapping.c over. As for CONFIG_KGDB, none of the Kconfig
files in the tree define it, so I'll let it languish for now.
Signed-off-by: Paul Mackerras <paulus@samba.org>
... and rename it to module_32.c since it is the 32-bit version.
The 32-bit and 64-bit ABIs are sufficiently different that having
a merged version isn't really practical.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Also renamed temp.c to tau_6xx.c (for thermal assist unit) and updated
the Kconfig option description and help text for CONFIG_TAU.
Signed-off-by: Paul Mackerras <paulus@samba.org>
No functional changes, but call it l2cr_6xx.S since it is specific
to 6xx-family (including G3/750 and G4/74xx) processors.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Since pSeries only wants to do something different in the idle loop when
there is no work to do, we can simplify the code by implementing
ppc_md.power_save functions instead of complete idle loops. There are
two versions: one for shared-processor partitions and one for dedicated-
processor partitions.
With this we also do a cede_processor() call on dedicated processor
partitions if the poll_pending() call indicates that the hypervisor
has work it wants to do.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This unifies the 32-bit (ARCH=ppc and ARCH=powerpc) and 64-bit idle
loops. It brings over the concept of having a ppc_md.power_save
function from 32-bit to ARCH=powerpc, which lets us get rid of
native_idle(). With this we will also be able to simplify the idle
handling for pSeries and cell.
Signed-off-by: Paul Mackerras <paulus@samba.org>
We only ever execute the loop once, so let's move it to a function
making it more readable. Cleanup patch, no functional change.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We were printing node ids in hex in one spot. Lets be consistent and
always print them in decimal.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently have a hack to flip the boot cpu and its secondary thread
to logical cpuid 0 and 1. This means the logical - physical mapping will
differ depending on which cpu is boot cpu. This is most apparent on
kexec, where we might kexec on any cpu and therefore change the mapping
from boot to boot.
The patch below does a first pass early on to work out the logical cpuid
of the boot thread. We then fix up some paca structures to match.
Ive also removed the boot_cpuid_phys variable for ppc64, to be
consistent we use get_hard_smp_processor_id(boot_cpuid) everywhere.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If an SPE attempts a DMA put to a local store after already doing
a get, the kernel must update the HW PTE to allow the write access.
This case was not being handled correctly.
From: Mike Kistler <mkistler@us.ibm.com>
Signed-off-by: Mike Kistler <mkistler@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
I'm not sure where the information came from, but I assumed
that doing cache-inhibited mappings for mmio regions was
sufficient.
It seems we also need the guarded bit set, like everyone
else, which is the default for ioremap.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
As noticed by Milton Miller, setting the initial affinity in
spider-pic can go wrong if the target node field was not orinally
empty.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Change the dynamic PCI probe function for pSeries to use
ppc_md.pci_probe_mode() when appropriate.
Signed-off-by: John Rose <johnrose@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Do not call prom exit prom_panic. It clears the screen and the exit
message is lost.
On some (or all?) pmacs it causes another crash when OF tries to print
the date and time in its banner.
Set of_platform earlier to catch more prom_panic() calls.
Signed-off-by: Olaf Hering <olh@suse.de>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The return statement is to prevent `warning: 'nid' might be used uninitialized
in this function'.
Cc: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The address of variable val in prom_init_stdout is passed to prom_getprop.
prom_getprop casts the pointer to u32 and passes it to call_prom in the hope
that OpenFirmware stores something there.
But the pointer is truncated in the lower bits and the expected value is
stored somewhere else.
In my testing I had a stackpointer of 0x0023e6b4. val was at offset 120,
wich has address 0x0023e72c. But the value passed to OF was 0x0023e728.
c00000000040b710: 3b 01 00 78 addi r24,r1,120
...
c00000000040b754: 57 08 00 38 rlwinm r8,r24,0,0,28
...
c00000000040b784: 80 01 00 78 lwz r0,120(r1)
...
c00000000040b798: 90 1b 00 0c stw r0,12(r27)
...
The stackpointer came from 32bit code.
The chain was yaboot -> zImage -> vmlinux
PowerMac OpenFirmware does appearently not handle the ELF sections
correctly. If yaboot was compiled in
/usr/src/packages/BUILD/lilo-10.1.1/yaboot, then the stackpointer is
unaligned. But the stackpointer is correct if yaboot is compiled in
/tmp/yaboot.
This bug triggered since 2.6.15, now prom_getprop is an inline
function. gcc clears the lower bits, instead of just clearing the
upper 32 bits.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
the mfc member of a new context was not initialized to zero,
which potentially leads to wild memory accesses.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch is layered on top of CONFIG_SPARSEMEM
and is patterned after direct mapping of LS.
This patch allows mmap() of the following regions:
"mfc", which represents the area from [0x3000 - 0x3fff];
"cntl", which represents the area from [0x4000 - 0x4fff];
"signal1" which begins at offset 0x14000; "signal2" which
begins at offset 0x1c000.
The signal1 & signal2 files may be mmap()'d by regular user
processes. The cntl and mfc file, on the other hand, may
only be accessed if the owning process has CAP_SYS_RAWIO,
because they have the potential to confuse the kernel
with regard to parallel access to the same files with
regular file operations: the kernel always holds a spinlock
when accessing registers in these areas to serialize them,
which can not be guaranteed with user mmaps,
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds a new file called 'mfc' to each spufs directory.
The file accepts DMA commands that are a subset of what would
be legal DMA commands for problem state register access. Upon
reading the file, a bitmask is returned with the completed
tag groups set.
The file is meant to be used from an abstraction in libspe
that is added by a different patch.
From the kernel perspective, this means a process can now
offload a memory copy from or into an SPE local store
without having to run code on the SPE itself.
The transfer will only be performed while the SPE is owned
by one thread that is waiting in the spu_run system call
and the data will be transferred into that thread's
address space, independent of which thread started the
transfer.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
An SPU does not have a way to implement system calls
itself, but it can create intercepts to the kernel.
This patch uses the method defined by the JSRE interface
for C99 host library calls from an SPU to implement
Linux system calls. It uses the reserved SPU stop code
0x2104 for this, using the structure layout and syscall
numbers for ppc64-linux.
I'm still undecided wether it is better to have a list
of allowed syscalls or a list of forbidden syscalls,
since we can't allow an SPU to call all syscalls that
are defined for ppc64-linux.
This patch implements the easier choice of them, with a
blacklist that only prevents an SPU from calling anything
that interacts with its own execution, e.g fork, execve,
clone, vfork, exit, spu_run and spu_create and everything
that deals with signals.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
