On ARMv7 CPUs that cache first level page table entries (like the
Cortex-A15), using a reserved ASID while changing the TTBR or flushing
the TLB is unsafe.
This is because the CPU may cache the first level entry as the result of
a speculative memory access while the reserved ASID is assigned. After
the process owning the page tables dies, the memory will be reallocated
and may be written with junk values which can be interpreted as global,
valid PTEs by the processor. This will result in the TLB being populated
with bogus global entries.
This patch avoids the use of a reserved context ID in the v7 switch_mm
and ASID rollover code by temporarily using the swapper_pg_dir pointed
at by TTBR1, which contains only global entries that are not tagged
with ASIDs.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch makes TTBR1 point to swapper_pg_dir so that global, kernel
mappings can be used exclusively on v6 and v7 cores where they are
needed.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The v6 and v7 implementations of flush_kern_dcache_area do not align
the passed MVA to the size of a cacheline in the data cache. If a
misaligned address is used, only a subset of the requested area will
be flushed. This has been observed to cause failures in SMP boot where
the secondary_data initialised by the primary CPU is not cacheline
aligned, causing the secondary CPUs to read incorrect values for their
pgd and stack pointers.
This patch ensures that the base address is cacheline aligned before
flushing the d-cache.
Cc: <stable@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 228e548e (net: Add sendmmsg socket system call) added the new
sendmmsg syscall. Add this to the syscall table for ARM.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
My existing email address may stop working in a month or two, so update
email to one that will continue working.
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
Hotplug support was added in 9f1890a (msm: hotplug: support cpu hotplug
on msm, 2010-12-02)
Signed-off-by: Jeff Ohlstein <johlstei@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ST-Ericsson modified ARM PrimeCell PL180 block has not got
an updated corresponding amba-id, althought the IP block has
changed in db8500v2. The change was done to the datactrl register.
Using the overrided subversion ID, account for this.
Signed-off-by: Philippe Langlais <philippe.langlais@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The DB8500v2 and DB5500 has a fifth version of the "PL023" and
PL180 blocks. However the ASIC engineers have forgot to bump the
revision in the PrimeCell peripheral ID registers. Since the
platform is aware of the actual silicon revision we need to
hard-code the periphid from the platform, bumping the subrevision
field to 1.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This makes a hardcoded periphid from the platform override any
magic number found in the hardware. This shall henceforth be used
when the information found in the hardware is either missing,
i.e. not encoding the CID with the magic cookie 0xb105f00d, or
incorrect such that the revision number should have been bumped in
hardware, but the silicon designer has failed to do so.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This is redundant. The correct ID number is right there in the
hardware anyway. We will introduce a mechanism later to hard-code
this for deviant cells.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Drivers which make use of the FIQ interrupt may require the state
of the FIQ mode registers to be preserved across suspend/resume.
Because the FIQ mode registers are not saved and restored
automatically by the kernel, driver authors will need to do the
appropriate save/restore in their own driver suspend/resume
handlers.
Implementing global automatic save/restore of the FIQ state does
not appear appropriate, since this by itself is not sufficient for
FIQ-based drivers to function correctly across suspend/resume in
any case.
This patch adds a brief explanatory note to fiq.h documenting the
requirement placed on driver authors.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* To remove the risk of inconvenient register allocation decisions
by the compiler, these functions are separated out as pure
assembler.
* The apcs frame manipulation code is not applicable for Thumb-2
(and also not easily compatible). Since it's not essential to
have a full frame on these leaf assembler functions, the frame
manipulation is removed, in the interests of simplicity.
* Split up ldm/stm instructions to be compatible with Thumb-2,
as well as avoiding instruction forms deprecated on >= ARMv7.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
sanity_check_meminfo walks over the registered memory banks and attempts
to split banks across lowmem and highmem when they would otherwise
overlap with the vmalloc space.
When SPARSEMEM is used, there are two potential problems that occur
when the virtual address of the start of a bank is equal to vmalloc_min.
1.) The end of lowmem is calculated as __pa(vmalloc_min - 1) + 1.
In the above scenario, this will give the end address of the
previous bank, rather than the actual bank we are interested in.
This value is later used as the memblock limit and artificially
restricts the total amount of available memory.
2.) The checks to determine whether or not a bank belongs to highmem
or not only check if __va(bank->start) is greater or less than
vmalloc_min. In the case that it is equal, the bank is incorrectly
treated as lowmem, which hoses the vmalloc area.
This patch fixes these two problems by checking whether the virtual
start address of a bank is >= vmalloc_min and then calculating
lowmem_end by finding the virtual end address of the highest lowmem
bank.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In commit eb33575c ("[ARM] Double check memmap is actually valid with a
memmap has unexpected holes V2"), a new function, memmap_valid_within,
was introduced to mmzone.h so that holes in the memmap which pass
pfn_valid in SPARSEMEM configurations can be detected and avoided.
The fix to this problem checks that the pfn <-> page linkages are
correct by calculating the page for the pfn and then checking that
page_to_pfn on that page returns the original pfn. Unfortunately, in
SPARSEMEM configurations, this results in reading from the page flags to
determine the correct section. Since the memmap here has been freed,
junk is read from memory and the check is no longer robust.
In the best case, reading from /proc/pagetypeinfo will give you the
wrong answer. In the worst case, you get SEGVs, Kernel OOPses and hung
CPUs. Furthermore, ioremap implementations that use pfn_valid to
disallow the remapping of normal memory will break.
This patch allows architectures to provide their own pfn_valid function
instead of using the default implementation used by sparsemem. The
architecture-specific version is aware of the memmap state and will
return false when passed a pfn for a freed page within a valid section.
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The kernel already prints its build timestamp during boot, no need to
repeat it in random drivers and produce different object files each
time.
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: cluster-devel@redhat.com
Signed-off-by: Michal Marek <mmarek@suse.cz>
The kernel already prints its build timestamp during boot, no need to
repeat it in random drivers and produce different object files each
time.
Cc: Armin Schindler <mac@melware.de>
Cc: netdev@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
Add ZONE_DMA to 31-bit config again. The performance gain is minimal
and hardly anybody cares anymore about a 31-bit kernel.
So add ZONE_DMA again to help with SLAB_CACHE_DMA removal for
!CONFIG_ZONE_DMA configurations.
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
If e.g. copy_from_user() generates a page fault and the kernel runs
into an OOM situation the system might lock up.
If the OOM killer sends a SIG_KILL to the current process it can't
handle it since it is stuck in a copy_from_user() - page fault loop.
Fix this by adding the same fix as other architectures have.
E.g. the x86 variant f86268 "x86/mm: Handle mm_fault_error() in kernel
space"
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Both functions take an int instead of an unsigned int. Fixes these
compile warnings:
kernel/sched.c:7167:2: warning: initialization from incompatible pointer type
kernel/sched.c:7170:2: warning: initialization from incompatible pointer type
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The hardware sample cpu hotplug notifier always returns NOTIFY_BAD.
That will prevent cpu hotplug if the machine is enabled for hardware
sampling even if it is not used. Fix the cpu hotplug notifier and
allow cpu hotplug if hardware sampling is unused.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Turn __access_ok() into a define and add a __chk_user_ptr() call
instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Merge irq.c and s390_ext.c into irq.c. That way all external interrupt
related functions are together.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Interrupt sources like pfault, sclp, dasd_diag and virtio all use the
service signal external interrupt subclass mask in control register 0
to enable and disable the corresponding interrupt.
Because no reference counting is implemented each subsystem thinks it
is the only user of subclass and sets and clears the bit like it wants.
This leads to case that unloading the dasd diag module under z/VM
causes both sclp and pfault interrupts to be masked. The result will
be locked up system sooner or later.
Fix this by introducing a new way to set (register) and clear
(unregister) the service signal subclass mask bit in cr0.
Also convert all drivers.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Always enable the service signal subclass mask bit in cr0, if pfault
is available. That way we use the normal cpu hotplug way to propagate
the subclass mask bit in cr0 instead of open coding it.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel already prints its build timestamp during boot, no need to
repeat it in random drivers and produce different object files each
time.
Acked-by: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
The kernel already prints its build timestamp during boot, no need to
repeat it in random drivers and produce different object files each
time.
Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: cluster-devel@redhat.com
Signed-off-by: Michal Marek <mmarek@suse.cz>
The kernel already prints its build timestamp during boot, no need to
repeat it in random drivers and produce different object files each
time.
Acked-by: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Michal Marek <mmarek@suse.cz>
The recently introduced NVIDIA GeForce GT 520 has 4 pins within a single
codec. Bump MAX_HDMI_PINS to accomodate this. Also bump MAX_HDMI_CVTS
to match it; this might be needed later too.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
When the PCM period size is set larger than 10 seconds, currently the
PCM core may abort the operation with DMA-error due to the fixed timeout
for 10 seconds. A similar problem is seen in the drain operation that
has a fixed timeout of 10 seconds, too.
This patch fixes the timeout length depending on the period size and
rate, also including the consideration of no_period_wakeup flag.
Reported-by: Raymond Yau <superquad.vortex2@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Oops, local-mounted of 'ocfs2_fops_no_plocks' is just missing the support
of unwritten_extents/punching-hole due to no func pointer was given correctly
to '.follocate' field.
Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
During dlm domain shutdown, o2dlm has to free all the lock resources. Ones that
have no locks and references are freed. Ones that have locks and/or references
are migrated to another node.
The first task in migration is finding a target. Currently we scan the lock
resource and find one node that either has a lock or a reference. This is not
very efficient in a parallel umount case as we might end up migrating the
lock resource to a node which itself may have to migrate it to a third node.
The patch scans the dlm->exit_domain_map to ensure the target node is not
leaving the domain. If no valid target node is found, o2dlm does not migrate
the resource but instead waits for the unlock and deref messages that will
allow it to free the resource.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>
This patch adds a new dlm message DLM_BEGIN_EXIT_DOMAIN_MSG and ups the dlm
protocol to 1.2.
o2dlm sends this new message in dlm_unregister_domain() to mark the beginning
of the exit domain. This message is sent to all nodes in the domain.
Currently o2dlm has no way of informing other nodes of its impending exit.
This information is useful as the other nodes could disregard the exiting
node in certain operations. For example, in resource migration. If two or
more nodes were umounting in parallel, it would be more efficient if o2dlm
were to choose a non-exiting node to be the new master node rather than an
exiting one.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>
Instead of looping over each irq and checking against the irq array
bounds, adjust the bounds before looping.
The old code will not free any irq if the irq + count is above
irq_virq_count because the test in the loop is testing irq + count
instead of irq + i.
This code checks the limits to avoid unsigned integer overflows.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The radix-tree code uses call_rcu when freeing internal elements.
We must protect against the elements being freed while we traverse
the tree, even if the returned pointer will still be valid.
While preparing a patch to expand the context in which
irq_radix_revmap_lookup will be called, I realized that the
radix tree was not locked.
When asked
For a normal call_rcu usage, is it allowed to read the structure in
irq_enter / irq_exit, without additional rcu_read_lock? Could an
element freed with call_rcu advance with the cpu still between
irq_enter/irq_exit (and irq_disabled())?
Paul McKenney replied:
Absolutely illegal to do so. OK for call_rcu_sched(), but a
flaming bug for call_rcu().
And thank you very much for finding this!!!
Further analysis:
In the current CONFIG_TREE_RCU implementation. CONFIG_TREE_PREEMPT_RCU
(and CONFIG_TINY_PREEMPT_RCU) uses explicit counters.
These counters are reflected from per-CPU to global in the
scheduling-clock-interrupt handler, so disabling irq does prevent the
grace period from completing. But there are real-time implementations
(such as the one use by the Concurrent guys) where disabling irq
does -not- prevent the grace period from completing.
While an alternative fix would be to switch radix-tree to rcu_sched, I
don't want to audit the other users of radix trees (nor put alternative
freeing in the library). The normal overhead for rcu_read_lock and
unlock are a local counter increment and decrement.
This does not show up in the rcu lockdep because in 2.6.34 commit
2676a58c98 (radix-tree: Disable RCU lockdep checking in radix tree)
deemed it too hard to pass the condition of the protecting lock
to the library.
Signed-off-by: Milton Miller <miltonm@bga.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Look up the descriptor and check that it is found in handle_one_irq
before checking if we are on the irq stack, and call the handler
directly using the descriptor if we are on the stack.
We need check irq_to_desc finds the descriptor to avoid a NULL
pointer dereference. It could have failed because the number from
ppc_md.get_irq was above NR_IRQS, or various exceptional conditions
with sparse irqs (eg race conditions while freeing an irq if its was
not shutdown in the controller).
fe12bc2c99 (genirq: Uninline and sanity check generic_handle_irq())
moved generic_handle_irq out of line to allow its use by interrupt
controllers in modules. However, handle_one_irq is core arch code.
It already knows the details of struct irq_desc and handling irqs in
the nested irq case. This will avoid the extra stack frame to return
the value we don't check.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since kmem caches are allocated before init_IRQ as noted in 3af259d155
(powerpc: Radix trees are available before init_IRQ), we now call
kmalloc in all cases and can can always call kfree if we are asked
to allocate a duplicate or conflicting IRQ_HOST_MAP_LEGACY host.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The comment claims we will call host->ops->map() to update the flags if
we find a previously established mapping, but we never did. We used
to call remap, but that call was removed in da05198002 (powerpc: Remove
irq_host_ops->remap hook).
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rename functions and arguments to reflect current usage. iic_cause_ipi
becomes iic_message_pass and iic_ipi_to_irq becomes iic_msg_to_irq,
and iic_request_ipi now takes a message (msg) instead of an ipi number.
Also mesg is renamed to msg.
Commit f1072939b6 (powerpc: Remove checks for MSG_ALL and
MSG_ALL_BUT_SELF) connected the smp_message_pass hook for cell to the
underlying iic_cause_IPI, a platform unique name. Later 23d72bfd8f
(powerpc: Consolidate ipi message mux and demux) added a cause_ipi
hook to the smp_ops, also used in message passing, but for controllers
that can not send 4 unique messages and require multiplexing. It is
even more confusing that the both take two arguments, but one is the
small message ordinal and the other is an opaque long data associated
with the cpu.
Since cell iic maps messages one to one to ipi irqs, rename the
function and argument to translate from ipi to message. Also make it
clear that iic_request_ipi takes a message number as the argument
for which ipi to create and request.
No functionional change, just renames to avoid future confusion.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The cell iic interrupt controller has enough software caused interrupts
to use a unique interrupt for each of the 4 messages powerpc uses.
This means each interrupt gets its own irq action/data combination.
Use the seperate, optimized, arch common ipi action functions
registered via the helper smp_request_message_ipi instead passing the
message as action data to a single action that then demultipexes to
the required acton via a switch statement.
smp_request_message_ipi will register the action as IRQF_PER_CPU
and IRQF_DISABLED, and WARN if the allocation fails for some reason,
so no need to print on that failure. It will return positive if
the message will not be used by the kernel, in which case we can
free the virq.
In addition to elimiating inefficient code, this also corrects the
error that a kernel built with kexec but without a debugger would
not register the ipi for kdump to notify the other cpus of a crash.
This also restores the debugger action to be static to kernel/smp.c.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that powerpc has removed its use of MSG_ALL_BUT_SELF and MSG_ALL
all these MSG_ flags are unused.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When page coalescing support was added recently, the MAX_HCALL_OPCODE
define was not updated for the newly added H_GET_MPP_X hcall.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 0837e3242c fixes a situation on POWER7
where events can roll back if a specualtive event doesn't actually complete.
This can raise a performance monitor exception. We need to catch this to ensure
that we reset the PMC. In all cases the PMC will be less than 256 cycles from
overflow.
This patch lifts Anton's fix for the problem in perf and applies it to oprofile
as well.
Signed-off-by: Eric B Munson <emunson@mgebm.net>
Cc: <stable@kernel.org> # as far back as it applies cleanly
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch implements the raw syscall tracepoints on PowerPC and exports
them for ftrace syscalls to use.
To minimise reworking existing code, I slightly re-ordered the thread
info flags such that the new TIF_SYSCALL_TRACEPOINT bit would still fit
within the 16 bits of the andi. instruction's UI field. The instructions
in question are in /arch/powerpc/kernel/entry_{32,64}.S to and the
_TIF_SYSCALL_T_OR_A with the thread flags to see if system call tracing
is enabled.
In the case of 64bit PowerPC, arch_syscall_addr and
arch_syscall_match_sym_name are overridden to allow ftrace syscalls to
work given the unusual system call table structure and symbol names that
start with a period.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Choosing TMPFS_XATTR default N was switching off TMPFS_POSIX_ACL,
even if it had been Y in oldconfig; and Linus reports that PulseAudio
goes subtly wrong unless it can use ACLs on /dev/shm.
Make TMPFS_POSIX_ACL select TMPFS_XATTR (and depend upon TMPFS),
and move the TMPFS_POSIX_ACL entry before the TMPFS_XATTR entry,
to avoid asking unnecessary questions then ignoring their answers.
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
