* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (144 commits)
powerpc/44x: Support 16K/64K base page sizes on 44x
powerpc: Force memory size to be a multiple of PAGE_SIZE
powerpc/32: Wire up the trampoline code for kdump
powerpc/32: Add the ability for a classic ppc kernel to be loaded at 32M
powerpc/32: Allow __ioremap on RAM addresses for kdump kernel
powerpc/32: Setup OF properties for kdump
powerpc/32/kdump: Implement crash_setup_regs() using ppc_save_regs()
powerpc: Prepare xmon_save_regs for use with kdump
powerpc: Remove default kexec/crash_kernel ops assignments
powerpc: Make default kexec/crash_kernel ops implicit
powerpc: Setup OF properties for ppc32 kexec
powerpc/pseries: Fix cpu hotplug
powerpc: Fix KVM build on ppc440
powerpc/cell: add QPACE as a separate Cell platform
powerpc/cell: fix build breakage with CONFIG_SPUFS disabled
powerpc/mpc5200: fix error paths in PSC UART probe function
powerpc/mpc5200: add rts/cts handling in PSC UART driver
powerpc/mpc5200: Make PSC UART driver update serial errors counters
powerpc/mpc5200: Remove obsolete code from mpc5200 MDIO driver
powerpc/mpc5200: Add MDMA/UDMA support to MPC5200 ATA driver
...
Fix trivial conflict in drivers/char/Makefile as per Paul's directions
Impact: New APIs
The old node_to_cpumask/node_to_pcibus returned a cpumask_t: these
return a pointer to a struct cpumask. Part of removing cpumasks from
the stack.
(Also replaces powerpc internal uses of node_to_cpumask).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since the QPACE (Chromodynamics Parallel Computing on the
Cell Broadband Engine) platform doesn't use a iommu, doesn't
have PCI devices and a MPIC much lesser setup and
configurations are needed. So far all devices are detected
as OF device. A notifier function is used to set the dma_ops
for the of_platform bus. Further this patch splits the
PPC_CELL_NATIVE into PPC_CELL_COMMON which are parts that are
shared with the QPACE platform and the rest.
Signed-off-by: Benjamin Krill <ben@codiert.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
CBE_THERM and OPROFILE_CELL both cannot be built without
SPU_FS disabled, so make the dependency explicit.
Reported-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Currently, we never set _PAGE_COHERENT in the PTEs, we just OR it in
in the hash code based on some CPU feature bit. We also manipulate
_PAGE_NO_CACHE and _PAGE_GUARDED by hand in all sorts of places.
This changes the logic so that instead, the PTE now contains
_PAGE_COHERENT for all normal RAM pages thay have I = 0 on platforms
that need it. The hash code clears it if the feature bit is not set.
It also adds some clean accessors to setup various valid combinations
of access flags and change various bits of code to use them instead.
This should help having the PTE actually containing the bit
combinations that we really want.
I also removed _PAGE_GUARDED from _PAGE_BASE on 44x and instead
set it explicitely from the TLB miss. I will ultimately remove it
completely as it appears that it might not be needed after all
but in the meantime, having it in the TLB miss makes things a
lot easier.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit d015fe995 'powerpc/cell/axon-msi: Retry on missing interrupt'
has turned a rare failure to kexec on QS22 into a reproducible
error, which we have now analysed.
The problem is that after a kexec, the MSIC hardware still points
into the middle of the old ring buffer. We set up the ring buffer
during reboot, but not the offset into it. On older kernels, this
would cause a storm of thousands of spurious interrupts after a
kexec, which would most of the time get dropped silently.
With the new code, we time out on each interrupt, waiting for
it to become valid. If more interrupts come in that we time
out on, this goes on indefinitely, which eventually leads to
a hard crash.
The solution in this commit is to read the current offset from
the MSIC when reinitializing it. This now works correctly, as
expected.
Reported-by: Dirk Herrendoerfer <d.herrendoerfer@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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>
An earlier patch from Jens Osterkamp attempted to fix GDB
watchpoints by enabling the DABRX register at boot time.
Unfortunately, this did not work on SMP setups, where
secondary CPUs were still using the power-on DABRX value.
This introduces the same change for secondary CPUs on cell
as well.
Reported-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Tested-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The MSI capture logic for the axon bridge can sometimes
lose interrupts in case of high DMA and interrupt load,
when it signals an MSI interrupt to the MPIC interrupt
controller while we are already handling another MSI.
Each MSI vector gets written into a FIFO buffer in main
memory using DMA, and that DMA access is normally flushed
by the actual interrupt packet on the IOIF. An MMIO
register in the MSIC holds the position of the last
entry in the FIFO buffer that was written. However,
reading that position does not flush the DMA, so that
we can observe stale data in the buffer.
In a stress test, we have observed the DMA to arrive
up to 14 microseconds after reading the register.
This patch works around this problem by retrying the
access to the FIFO buffer.
We can reliably detect the conditioning by writing
an invalid MSI vector into the FIFO buffer after
reading from it, assuming that all MSIs we get
are valid. After detecting an invalid MSI vector,
we udelay(1) in the interrupt cascade for up to
100 times before giving up.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently, we can end up in an infinite loop if we get a signal
while the kernel has faulted in spufs_ps_fault. Eg:
alarm(1);
write(fd, some_spu_psmap_register_address, 4);
- the write's copy_from_user will fault on the ps mapping, and
signal_pending will be non-zero. Because returning from the fault
handler will never clear TIF_SIGPENDING, so we'll just keep faulting,
resulting in an unkillable process using 100% of CPU.
This change returns VM_FAULT_SIGBUS if there's a fatal signal pending,
letting us escape the loop.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Conflicts:
security/keys/internal.h
security/keys/process_keys.c
security/keys/request_key.c
Fixed conflicts above by using the non 'tsk' versions.
Signed-off-by: James Morris <jmorris@namei.org>
Pass credentials through dentry_open() so that the COW creds patch can have
SELinux's flush_unauthorized_files() pass the appropriate creds back to itself
when it opens its null chardev.
The security_dentry_open() call also now takes a creds pointer, as does the
dentry_open hook in struct security_operations.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.org
Signed-off-by: James Morris <jmorris@namei.org>
This fixes this error on Cell when CONFIG_KEXEC = n:
arch/powerpc/platforms/cell/ras.c:299: error: implicit declaration of function 'crash_shutdown_register'
We have to include <asm/kexec.h> because it contains the dummy
definition of crash_shutdown_register that is used when
CONFIG_KEXEC=n, but <linux/kexec.h> doesn't include <asm/kexec.h> in
that case.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
After the merge of the 32 and 64bit DMA code, dma_direct_ops lost
their map/unmap_single() functions but gained map/unmap_page(). This
caused a problem for Cell because Cell's dma_iommu_fixed_ops called
the dma_direct_ops if the fixed linear mapping was to be used or the
iommu ops if the dynamic window was to be used. So in order to fix
this problem we need to update the 64bit DMA code to use
map/unmap_page.
First, we update the generic IOMMU code so that iommu_map_single()
becomes iommu_map_page() and iommu_unmap_single() becomes
iommu_unmap_page(). Then we propagate these changes up through all
the callers of these two functions and in the process update all the
dma_mapping_ops so that they have map/unmap_page rahter than
map/unmap_single. We can do this because on 64bit there is no HIGHMEM
memory so map/unmap_page ends up performing exactly the same function
as map/unmap_single, just taking different arguments.
This has no affect on drivers because the dma_map_single_attrs() just
ends up calling the map_page() function of the appropriate
dma_mapping_ops and similarly the dma_unmap_single_attrs() calls
unmap_page().
This fixes an oops on Cell blades, which oops on boot without this
because they call dma_direct_ops.map_single, which is NULL.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
linux/crash_dump.h defines is_kdump_kernel() to be used by code that
needs to know if the previous kernel crashed instead of a (clean) boot
or reboot.
This updates the just added powerpc code to use it. This is needed
for the next commit, which will remove __kdump_flag.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds relocatable kernel support for kdump. With this one can
use the same regular kernel to capture the kdump. A signature (0xfeed1234)
is passed in r6 from panic code to the next kernel through kexec_sequence
and purgatory code. The signature is used to differentiate between
kdump kernel and non-kdump kernels.
The purgatory code compares the signature and sets the __kdump_flag in
head_64.S. During the boot up, kernel code checks __kdump_flag and if it
is set, the kernel will behave as relocatable kdump kernel. This kernel
will boot at the address where it was loaded by kexec-tools ie. at the
address reserved through crashkernel boot parameter.
CONFIG_CRASH_DUMP depends on CONFIG_RELOCATABLE option to build kdump
kernel as relocatable. So the same kernel can be used as production and
kdump kernel.
This patch incorporates the changes suggested by Paul Mackerras to avoid
GOT use and to avoid two copies of the code.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We used to assume that even numbered threads were the primary
threads, ie those that would be listed and started as a cpu from
open firmware. Replace a left over is even (% 2) check with a check
for it being a primary thread and update the comments.
Tested with a debug print on pseries, identical code found for cell.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds a comment to clarify why atomic_dec_if_positive is being used
to decrement gang's aff_sched_count on SPU context unbind.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
This patch improves redability of the code responsible for trying to find
a node with enough SPUs not committed to other affinity gangs.
An additional check is also added, to avoid taking into account gangs that
have no SPU affinity.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
With most file readers (eg cat, dd), reading a context's regs file will
result in two reads: the first to read the data, and the second to
return EOF. Because each read performs a spu_acquire_saved, we end up
descheduling and re-scheduling the context twice.
This change does a simple check to see if we'd return EOF before
calling spu_acquire_saved(), saving the extra schedule operation.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Currently, read() on the sputrace log will block until the read buffer
is full. This makes it difficult to retrieve the end of the buffer, as
the user will need to read with the right-sized buffer.
In a similar method as 91553a1b5e0df006a3573a88d98ee7cd48a3818a, this
change makes the switch_log return if there has already been data
read.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Currently, we use ctx->mapping_lock and ctx->switch_log->lock for the
context switch log. The mapping lock only prevents concurrent open()s,
so we require the switch_lock->lock for reads.
Since writes to the switch log buffer occur on context switches, we're
better off synchronising with the state_mutex, which is held during a
switch. Since we're serialised througout the buffer reads and writes,
we can use the state mutex to protect open and release too, and
can now kfree() the log buffer on release. This allows us to perform
the switch log notify without taking any extra locks.
Because the buffer is only present while the file is open, we can use
it to prevent multiple simultaneous openers.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Currently, read() on the sputrace buffer will only return data when
the user buffer is exhausted. This may mean that we never see the
end of the event log, unless we read() with exactly the right-sized
buffer.
This change makes sputrace_read not block if we have data ready to
return.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Currently, sputrace will start logging to the event buffer before the
log buffer has been open()ed. This results in a heap of "lost samples"
warnings if the sputrace file hasn't yet been opened.
Since the buffer is reset on open() anyway, there's no need to enable
logging when no-one has opened the log.
Because open clears the log, make it return EBUSY for mutliple open
calls.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
We need a marker_synchronize_unregister() before the end of exit() to make sure
every probe callers have exited the non preemptible section and thus are not
executing the probe code anymore.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.
This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A mutex_unlock(&gang->aff_mutex) in spufs_create_context() is missing
in case spufs_context_open() fails. As a result, spu_create syscall
and spu_get_idle() may block.
This patch adds the mutex_unlock.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Acked-by: Andre Detsch <adetsch@br.ibm.com>
Currently, an empty spufs root inode has nlink count of 1. However,
the directory has two links; / -> spu and /spu/ -> .
This change increments the link count of the root inode in spufs.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Use the struct device's numa_node instead; use accessor functions
to get/set numa_node.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
We currently have a race when scheduling a context to a SPE -
after we have found a runnable context in spusched_tick, the same
context may have been scheduled by spu_activate().
This may result in a panic if we try to unschedule a context that has
been freed in the meantime.
This change exits spu_schedule() if the context has already been
scheduled, so we don't end up scheduling it twice.
Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
We currently have a race for a free SPE. With one thread doing a
spu_yield(), and another doing a spu_activate():
thread 1 thread 2
spu_yield(oldctx) spu_activate(ctx)
__spu_deactivate(oldctx)
spu_unschedule(oldctx, spu)
spu->alloc_state = SPU_FREE
spu = spu_get_idle(ctx)
- searches for a SPE in
state SPU_FREE, gets
the context just
freed by thread 1
spu_schedule(ctx, spu)
spu->alloc_state = SPU_USED
spu_schedule(newctx, spu)
- assumes spu is still free
- tries to schedule context on
already-used spu
This change introduces a 'free_spu' flag to spu_unschedule, to indicate
whether or not the function should free the spu after descheduling the
context. We only set this flag if we're not going to re-schedule
another context on this SPU.
Add a comment to document this behaviour.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Commit 8d5636fbca introduced a reference
count on SPU contexts during find_victim, but this may cause a leak in
the reference count if we later find a better contender for a context to
unschedule.
Change the reference to after we've found our victim context, so we
don't do the extra get_spu_context().
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Based on an original patch from Christoph Hellwig <hch@lst.de>.
Currently, there is a possible reference-after-free in the spusched
code - contexts may be freed after we have released their state_mutex
in spusched_tick and find_victim.
This change takes a reference to the context before releasing the
mutex, so that the context doesn't get destroyed.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
