The MMU context_lock can be taken from switch_mm() while the
rq->lock is held. The rq->lock can also be taken from interrupts,
thus if we get interrupted in destroy_context() with the context
lock held and that interrupt tries to take the rq->lock, there's
a possible deadlock scenario with another CPU having the rq->lock
and calling switch_mm() which takes our context lock.
The fix is to always ensure interrupts are off when taking our
context lock. The switch_mm() path is already good so this fixes
the destroy_context() path.
While at it, turn the context lock into a new style spinlock.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch fixes a couple of issues that can happen as a result
of steal_context() dropping the context_lock when all possible
PIDs are ineligible for stealing (hopefully an extremely hard to
hit occurence).
This case exposes the possibility of a stale context_mm[] entry
to be seen since destroy_context() doesn't clear it and the free
map isn't re-tested. It also means steal_context() will not notice
a context freed while the lock was help, thus possibly trying to
steal a context when a free one was available.
This fixes it by always returning to the caller from steal_context
when it dropped the lock with a return value that causes the
caller to re-samble the number of free contexts, along with
properly clearing the context_mm[] array for destroyed contexts.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reworked by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds block-step support on powerpc, including a PTRACE_SINGLEBLOCK
request for ptrace.
The BookE implementation is tweaked to fire a single step after a
block step in order to mimmic the server behaviour.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Added support for the new xps tft controller. The new core
has PLB interface support in addition to existing DCR interface.
Removed platform device support as both MicroBlaze and PowerPC
use device tree.
Previously, the dcr interface was assumed to be used in mmio mode,
and the register space of the dcr interface was precomputed and stuffed
into the device tree. This driver now makes use of the new dcr
infrastructure to represent the dcr interface. This enables the dcr
interface to be connected directly to a native dcr interface in a clean
way.
Added compatibility for ml507 dvi core.
Signed-off-by: Suneel <suneelg@xilinx.com>
Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
As subject says, add dts files for Xilinx ML510 reference design with
the PCI host bridge device.
Signed-off-by: Roderick Colenbrander <thunderbird2k@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch refactors some of the xilinx_intc interrupt controller driver
and adds support for cascading an i8259 off one of the irq lines.
This patch was based on the ML510 support work done by Roderick
Colenbrander.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch adds support for the Xilinx plbv46-pci-1.03.a PCI host
bridge IPcore.
Signed-off-by: Roderick Colenbrander <thunderbird2k@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
It was __devinit, but it is also within a CONFIG_HOTPLUG guarded section
of code, so the __devinit does nothing but cause the following warning:
WARNING: vmlinux.o(.text+0x107a8): Section mismatch in reference from the function pcibios_finish_adding_to_bus() to the function .devinit.text:pcibios_claim_one_bus()
The function pcibios_finish_adding_to_bus() references
the function __devinit pcibios_claim_one_bus().
This is often because pcibios_finish_adding_to_bus lacks a __devinit
annotation or the annotation of pcibios_claim_one_bus is wrong.
It is also only (externally) used in arch/powerpc/kernel/of_platform.c
which cannot be built as a module so don't export it.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These macros were used in the original port, but since commit
e4486fe316 (ftrace, use probe_kernel API to modify code) they
are unused.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch updates the output from /proc/ppc64/lparcfg to display the
processor virtualization resource allocations for a shared processor
partition.
This information is already gathered via the h_get_ppp call, we just
have to make sure that the ibm,partition-performance-parameters-level
property is >= 1 to ensure that the information is valid.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
RTAS event scan has to run across all cpus. Right now we use a kernel
thread and set_cpus_allowed but in doing so we wake up the previous cpu
unnecessarily.
Some ftrace output shows this:
previous cpu (2):
[002] 7.022331: sched_switch: task swapper:0 [140] ==> rtasd:194 [120]
[002] 7.022338: sched_switch: task rtasd:194 [120] ==> migration/2:9 [0]
[002] 7.022344: sched_switch: task migration/2:9 [0] ==> swapper:0 [140]
next cpu (3):
[003] 7.022345: sched_switch: task swapper:0 [140] ==> rtasd:194 [120]
[003] 7.022371: sched_switch: task rtasd:194 [120] ==> swapper:0 [140]
We can use schedule_delayed_work_on and avoid the unnecessary wakeup.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This bit would get enabled sometimes (probably after suspend/resume), so the
fan would run at full speed below the temperature thresholds, but slow down and
eventually stop if temperatures rose above the thresholds... not exactly what
you want.
Signed-off-by: Michel Dänzer <michel@daenzer.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We can compile and boot with NR_CPUS=8192, so make this the max. 1024
was an arbitrary decision anyway.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Fix up dma_alloc_coherent() on platforms without cache coherency.
powerpc: Minor cleanups of kernel virt address space definitions
powerpc: Move dma-noncoherent.c from arch/powerpc/lib to arch/powerpc/mm
Revert "powerpc: Rework dma-noncoherent to use generic vmalloc layer"
Fix up renamed filenames in comments in fs/cachefiles/internal.h.
Originally, the files were all called cf-xxx.c, but they got renamed to
just xxx.c.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up renamed filenames in comments in fs/fscache/internal.h.
Originally, the files were all called fsc-xxx.c, but they got renamed to
just xxx.c.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A recent patch to raid5.c use min on an int and a sector_t.
This isn't allowed.
So change it to min_t(sector_t,x,y).
Signed-off-by: NeilBrown <neilb@suse.de>
The implementation we just revived has issues, such as using a
Kconfig-defined virtual address area in kernel space that nothing
actually carves out (and thus will overlap whatever is there),
or having some dependencies on being self contained in a single
PTE page which adds unnecessary constraints on the kernel virtual
address space.
This fixes it by using more classic PTE accessors and automatically
locating the area for consistent memory, carving an appropriate hole
in the kernel virtual address space, leaving only the size of that
area as a Kconfig option. It also brings some dma-mask related fixes
from the ARM implementation which was almost identical initially but
grew its own fixes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Benjamin Herrenschmidt
Roland McGrath
John Linn
Roderick Colenbrander
Grant Likely
Stephen Rothwell
Michael Ellerman
Nathan Fontenot
Anton Blanchard
Michel Dänzer
roel kluin
Michael Neuling
Linus Torvalds
David Howells
NeilBrown