The problem is caused by the interaction of two features in the Linux
memory management code.
A processes address space is described by a struct mm_struct, and
every thread has a pointer to the mm it should run in. The exception
to this are kernel threads, which don't have an mm, and so borrow
the mm from the last thread which ran. The system is bootstrapped
by the initial kernel thread using init's mm (even though init hasn't
been created yet, its mm is the static init_mm).
The other feature is how the kernel handles the page table which
describes the portion of the address space which is only visible when
executing inside the kernel, and which is shared by all threads. On
the SH4 the only portion of the kernel's address space which described
using the page table is called P3, from 0xc0000000 to 0xdfffffff. This
portion of the address space is divided into three:
- mappings for dma_alloc_coherent()
- mappings for vmalloc() and ioremap()
- fixmap mappings, primarily used in copy_user_pages() to create
kernel mappings of user pages with the correct cache colour.
To optimise the TLB miss handler we don't want to add an additional
condition which checks whether the faulting address is in the user or
the kernel portion of the address space, and so all page tables have a
common portion which describes the kernel part of the address
space. As the SH4 uses a two level page table, only the kernel portion
of first level page table (the pgd entries) is duplicated. These all
point to the same second level entries (the pte's), and so no memory
is wasted.
The reference page table for the kernel is called the swapper_pg_dir,
and when a new page table is created for a new process the kernel
portion of the page table is copied from swapper_pg_dir. This works
fine when changes only occur in the second level of the kernel's page
table, or the first level entries are created before any new user
processes. However if a change occurs to the first level of the page
table, and there are existing processes which don't have this entry in
their page table, this new entry needs to be added. This is done on
demand, when the kernel accesses a P3 address which isn't mapped using
the current page table, the code in vmalloc_fault() copies the entry
from the reference page table (swapper_pg_dir) into the current
processes page table.
The bug which this patch addresses is that the code in vmalloc_fault()
was not copying addresses which fell in the dma_alloc_coherent()
portion of the address space, and it should have been copying any P3
address.
Why we hadn't seen this before, and what made this hard to reproduce,
is that normally the kernel will have called dma_alloc_coherent(), and
accessed the memory mapping created, before any user process
runs. Typically drivers such as USB or SATA will have created and used
mappings of this type during the kernel initialisation, when probing
for the attached devices, before init runs. Ethernet is slightly
different, as it normally only creates and accesses
dma_alloc_coherent() mappings when the network is brought up, but if
kernel level IP configuration is used this will also occur before any
user space process runs. So the first reproduction of this problem
which we saw was occurred when USB and SATA were removed from the
kernel, and then bring up Ethernet from user space using ifconfig.
I'd like to thank Joseph Bormolini who did the hard work reducing the
problem to this simple to reproduce criteria.
In your case the situation is slightly different, and turns out to
depends on the exact kernel configuration (which we had) and your
ramdisk contents (which we didn't - hence the need for some assumptions).
In this case the problem is a side effect of kernel level module
loading. Kernel subsystems sometimes trigger the load of kernel
modules directly, for example the crypto subsystem tries to load the
cryptomgr and MTD tries to load modules for Flash partitioning if
these are not built into the kernel. This is done by the kernel
creating a user process which runs insmod to try and load the
appropriate module.
In order for this to cause problems the system must be running with a
initrd or initramfs, which contains an insmod executable - if the
kernel can't find an insmod to run, no user process is created, and
the problem doesn't occur. If an insmod is found, a process is
created to run it, which will inherit the kernel portion of the
swapper_pg_dir first level page table. It doesn't matter whether the
inmod is successful or not, but when the the kernel scheduler context
switches back to the kernel initialisation thread, the insmod's mm is
'borrowed' by the kernel thread, as it doesn't have an address space
of its own. (Reference counting is used to ensure this mm is not
destroyed, even though the user process which caused its creation may no
longer exist.) If this address space doesn't have a first level page
table entry for the consistent mappings, and a driver tries to access
such a mapping, we are in the same situation as described above,
except this time in a kernel thread rather than a user thread
executing inside the kernel.
See bugzilla: 15425, 15836, 15862, 16106, 16793
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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Merge tag 'sh-for-linus' of git://github.com/pmundt/linux-sh
Pull SuperH fixes from Paul Mundt.
* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
sh: fix clock-sh7757 for the latest sh_mobile_sdhi driver
serial: sh-sci: use serial_port_in/out vs sci_in/out.
sh: vsyscall: Fix up .eh_frame generation.
sh: dma: Fix up device attribute mismatch from sysdev fallout.
sh: dwarf unwinder depends on SHcompact.
sh: fix up fallout from system.h disintegration.
Pull DMA mapping branch from Marek Szyprowski:
"Short summary for the whole series:
A few limitations have been identified in the current dma-mapping
design and its implementations for various architectures. There exist
more than one function for allocating and freeing the buffers:
currently these 3 are used dma_{alloc, free}_coherent,
dma_{alloc,free}_writecombine, dma_{alloc,free}_noncoherent.
For most of the systems these calls are almost equivalent and can be
interchanged. For others, especially the truly non-coherent ones
(like ARM), the difference can be easily noticed in overall driver
performance. Sadly not all architectures provide implementations for
all of them, so the drivers might need to be adapted and cannot be
easily shared between different architectures. The provided patches
unify all these functions and hide the differences under the already
existing dma attributes concept. The thread with more references is
available here:
http://www.spinics.net/lists/linux-sh/msg09777.html
These patches are also a prerequisite for unifying DMA-mapping
implementation on ARM architecture with the common one provided by
dma_map_ops structure and extending it with IOMMU support. More
information is available in the following thread:
http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
More works on dma-mapping framework are planned, especially in the
area of buffer sharing and managing the shared mappings (together with
the recently introduced dma_buf interface: commit d15bd7ee44
"dma-buf: Introduce dma buffer sharing mechanism").
The patches in the current set introduce a new alloc/free methods
(with support for memory attributes) in dma_map_ops structure, which
will later replace dma_alloc_coherent and dma_alloc_writecombine
functions."
People finally started piping up with support for merging this, so I'm
merging it as the last of the pending stuff from the merge window.
Looks like pohmelfs is going to wait for 3.5 and more external support
for merging.
* 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
common: DMA-mapping: add NON-CONSISTENT attribute
common: DMA-mapping: add WRITE_COMBINE attribute
common: dma-mapping: introduce mmap method
common: dma-mapping: remove old alloc_coherent and free_coherent methods
Hexagon: adapt for dma_map_ops changes
Unicore32: adapt for dma_map_ops changes
Microblaze: adapt for dma_map_ops changes
SH: adapt for dma_map_ops changes
Alpha: adapt for dma_map_ops changes
SPARC: adapt for dma_map_ops changes
PowerPC: adapt for dma_map_ops changes
MIPS: adapt for dma_map_ops changes
X86 & IA64: adapt for dma_map_ops changes
common: dma-mapping: introduce generic alloc() and free() methods
Adapt core SH architecture code for dma_map_ops changes: replace
alloc/free_coherent with generic alloc/free methods.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
The cache functions lock out interrupts for long periods; this patch
reduces the impact when operating on large address ranges. In such
cases it will:
- Invalidate the entire cache rather than individual addresses.
- Do nothing when flushing the operand cache in write-through mode.
- When flushing the operand cache in write-back mdoe, index the
search for matching addresses on the cache entires instead of the
addresses to flush
Note: sh2a__flush_purge_region was only invalidating the operand
cache, this adds flush.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now all ARCH_POPULATES_NODE_MAP archs select HAVE_MEBLOCK_NODE_MAP -
there's no user of early_node_map[] left. Kill early_node_map[] and
replace ARCH_POPULATES_NODE_MAP with HAVE_MEMBLOCK_NODE_MAP. Also,
relocate for_each_mem_pfn_range() and helper from mm.h to memblock.h
as page_alloc.c would no longer host an alternative implementation.
This change is ultimately one to one mapping and shouldn't cause any
observable difference; however, after the recent changes, there are
some functions which now would fit memblock.c better than page_alloc.c
and dependency on HAVE_MEMBLOCK_NODE_MAP instead of HAVE_MEMBLOCK
doesn't make much sense on some of them. Further cleanups for
functions inside HAVE_MEMBLOCK_NODE_MAP in mm.h would be nice.
-v2: Fix compile bug introduced by mis-spelling
CONFIG_HAVE_MEMBLOCK_NODE_MAP to CONFIG_MEMBLOCK_HAVE_NODE_MAP in
mmzone.h. Reported by Stephen Rothwell.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
The only function of memblock_analyze() is now allowing resize of
memblock region arrays. Rename it to memblock_allow_resize() and
update its users.
* The following users remain the same other than renaming.
arm/mm/init.c::arm_memblock_init()
microblaze/kernel/prom.c::early_init_devtree()
powerpc/kernel/prom.c::early_init_devtree()
openrisc/kernel/prom.c::early_init_devtree()
sh/mm/init.c::paging_init()
sparc/mm/init_64.c::paging_init()
unicore32/mm/init.c::uc32_memblock_init()
* In the following users, analyze was used to update total size which
is no longer necessary.
powerpc/kernel/machine_kexec.c::reserve_crashkernel()
powerpc/kernel/prom.c::early_init_devtree()
powerpc/mm/init_32.c::MMU_init()
powerpc/mm/tlb_nohash.c::__early_init_mmu()
powerpc/platforms/ps3/mm.c::ps3_mm_add_memory()
powerpc/platforms/embedded6xx/wii.c::wii_memory_fixups()
sh/kernel/machine_kexec.c::reserve_crashkernel()
* x86/kernel/e820.c::memblock_x86_fill() was directly setting
memblock_can_resize before populating memblock and calling analyze
afterwards. Call memblock_allow_resize() before start populating.
memblock_can_resize is now static inside memblock.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "H. Peter Anvin" <hpa@zytor.com>
memblock_init() initializes arrays for regions and memblock itself;
however, all these can be done with struct initializers and
memblock_init() can be removed. This patch kills memblock_init() and
initializes memblock with struct initializer.
The only difference is that the first dummy entries don't have .nid
set to MAX_NUMNODES initially. This doesn't cause any behavior
difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "H. Peter Anvin" <hpa@zytor.com>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
Add PHYSICAL_START kernel configuration parameter to set the address at
which the kernel should be loaded.
It has been observed on an sh7757lcr that simply modifying MEMORY_START
does not achieve this goal for 32bit sh. This is due to MEMORY_OFFSET in
arch/sh/kernel/vmlinux.lds.S bot being based on MEMORY_START on such
systems.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (123 commits)
perf: Remove the nmi parameter from the oprofile_perf backend
x86, perf: Make copy_from_user_nmi() a library function
perf: Remove perf_event_attr::type check
x86, perf: P4 PMU - Fix typos in comments and style cleanup
perf tools: Make test use the preset debugfs path
perf tools: Add automated tests for events parsing
perf tools: De-opt the parse_events function
perf script: Fix display of IP address for non-callchain path
perf tools: Fix endian conversion reading event attr from file header
perf tools: Add missing 'node' alias to the hw_cache[] array
perf probe: Support adding probes on offline kernel modules
perf probe: Add probed module in front of function
perf probe: Introduce debuginfo to encapsulate dwarf information
perf-probe: Move dwarf library routines to dwarf-aux.{c, h}
perf probe: Remove redundant dwarf functions
perf probe: Move strtailcmp to string.c
perf probe: Rename DIE_FIND_CB_FOUND to DIE_FIND_CB_END
tracing/kprobe: Update symbol reference when loading module
tracing/kprobes: Support module init function probing
kprobes: Return -ENOENT if probe point doesn't exist
...
The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.
For the various event classes:
- hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
the PMI-tail (ARM etc.)
- tracepoint: nmi=0; since tracepoint could be from NMI context.
- software: nmi=[0,1]; some, like the schedule thing cannot
perform wakeups, and hence need 0.
As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).
The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch fixes a icache/dcache address-array start address while
dumping its entires in debugfs. Perviously the code was attempting to
remember the address in static variable, which is no more required
for debugfs, as the function can be executed in one pass.
Without this patch the start address ends up in wrong place and the
/sys/kernel/debug/sh/icache or dcache debugfs contents may not be correct.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Cc: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
sh64 doesn't define a P1SEGADDR, resulting in a build failure. The proper
mapping can be attained for both sh32 and 64 via the CAC_ADDR macro, so
switch to that instead.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Fold all the mmu_gather rework patches into one for submission
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This converts the PMB code over to use the new syscore_ops and kills off
the old sysdev utilization, as per Rafael's example.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch enables gcov kernel profiling over the whole kernel for sh.
Profiling of specific files individually already worked. A handful of
files have to be explicitly excluded from the profiling to avoid
breaking things, notably pmb.c.
Signed-off-by: Chris Smith <chris.smith@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This resolves a problem seen when using the Android dynamic linker.
Sometimes the dynamic linker would seg-fault at start up and this
was eventually traced to the handling of a COW fault for a page which
was being modified by the linker. If there was no cache aliasing between
the kernel and the user page, the page was not flushed, leaving the
newly copied data in the D-cache. However when executing instructions
from that page, the I-cache is filled directly from external memory,
rather than the D-cache, and causing garbage to be executed.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
pte alloc routines must wait for split_huge_page if the pmd is not present
and not null (i.e. pmd_trans_splitting). The additional branches are
optimized away at compile time by pmd_trans_splitting if the config option
is off. However we must pass the vma down in order to know the anon_vma
lock to wait for.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts:
MAINTAINERS
arch/arm/mach-omap2/pm24xx.c
drivers/scsi/bfa/bfa_fcpim.c
Needed to update to apply fixes for which the old branch was too
outdated.
This follows the ARM change c01778001a
("ARM: 6379/1: Assume new page cache pages have dirty D-cache") for the
same rationale:
There are places in Linux where writes to newly allocated page
cache pages happen without a subsequent call to flush_dcache_page()
(several PIO drivers including USB HCD). This patch changes the
meaning of PG_arch_1 to be PG_dcache_clean and always flush the
D-cache for a newly mapped page in update_mmu_cache().
This addresses issues seen with executing binaries from MMC, in
addition to some of the other HCDs that don't explicitly do cache
management for their pipe-in buffers.
Requested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The nommu code has regressed somewhat in that 29BIT gets set for the
SH-2/2A configs regardless of the fact that they are really 32BIT sans
MMU or PMB. This does a bit of tidying to get nommu properly selecting
32BIT as it was before.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (110 commits)
sh: i2c-sh7760: Replase from ctrl_* to __raw_*
sh: clkfwk: Shuffle around to match the intc split up.
sh: clkfwk: modify for_each_frequency end condition
sh: fix clk_get() error handling
sh: clkfwk: Fix fault in frequency iterator.
sh: clkfwk: Add a helper for rate rounding by divisor ranges.
sh: clkfwk: Abstract rate rounding helper.
sh: clkfwk: support clock remapping.
sh: pci: Convert to upper/lower_32_bits() helpers.
sh: mach-sdk7786: Add support for the FPGA SRAM.
sh: Provide a generic SRAM pool for tiny memories.
sh: pci: Support secondary FPGA-driven PCIe clocks on SDK7786.
sh: pci: Support slot 4 routing on SDK7786.
sh: Fix up PMB locking.
sh: mach-sdk7786: Add support for fpga gpios.
sh: use pr_fmt for clock framework, too.
sh: remove name and id from struct clk
sh: free-without-alloc fix for sh_mobile_lcdcfb
sh: perf: Set up perf_max_events.
sh: perf: Support SH-X3 hardware counters.
...
Fix up trivial conflicts (perf_max_events got removed) in arch/sh/kernel/perf_event.c
This sets up a generic SRAM pool for CPUs and platform code to insert
their otherwise unused memories into. A simple alloc/free interface is
provided (lifed from avr32) for generic code.
This only applies to tiny SRAMs that are otherwise unmanaged, and does
not take in to account the more complex SRAMs sitting behind transfer
engines, or that employ an I/D split.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This first converts the PMB locking over to raw spinlocks, and secondly
fixes up a nested locking issue that was triggering lockdep early on:
swapper/0 is trying to acquire lock:
(&pmbe->lock){......}, at: [<806be9bc>] pmb_init+0xf4/0x4dc
but task is already holding lock:
(&pmbe->lock){......}, at: [<806be98e>] pmb_init+0xc6/0x4dc
other info that might help us debug this:
1 lock held by swapper/0:
#0: (&pmbe->lock){......}, at: [<806be98e>] pmb_init+0xc6/0x4dc
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We need to round memory regions correctly -- specifically, we need to
round reserved region in the more expansive direction (lower limit
down, upper limit up) whereas usable memory regions need to be rounded
in the more restrictive direction (lower limit up, upper limit down).
This introduces two set of inlines:
memblock_region_memory_base_pfn()
memblock_region_memory_end_pfn()
memblock_region_reserved_base_pfn()
memblock_region_reserved_end_pfn()
Although they are antisymmetric (and therefore are technically
duplicates) the use of the different inlines explicitly documents the
programmer's intention.
The lack of proper rounding caused a bug on ARM, which was then found
to also affect other architectures.
Reported-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4CB4CDFD.4020105@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
While sh previously had its own debugfs root, there now exists a
common arch_debugfs_dir prototype, so we switch everything over to
that. Presumably once more architectures start making use of this
we'll be able to just kill off the stub kdebugfs wrapper.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This fixes up the nommu build with a stub definition for
__flush_tlb_global(), now used by the reboot code.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This follows the x86 change off of memset() and on to an unconditional
__GFP_ZERO for wrapping in to optimized page clearing by way of
clear_highpage().
Signed-off-by: Andrew Murray <amurray@mpc-data.co.uk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
via following scripts
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/lmb/memblock/g' \
-e 's/LMB/MEMBLOCK/g' \
$FILES
for N in $(find . -name lmb.[ch]); do
M=$(echo $N | sed 's/lmb/memblock/g')
mv $N $M
done
and remove some wrong change like lmbench and dlmb etc.
also move memblock.c from lib/ to mm/
Suggested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This provides a sledgehammer approach for clearing the TLBs, only to be
used in cases where we know we will never want to use the mappings again
and have no interest in preserving state. This also destroys wired
entries.
The primary use for this is when we are either entering or exiting the
kernel completely, in the latter case as a precursor for CPU reset by
MMU.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
page_table_range_init() presently allocates a PUD page for the 3-level
page table case on X2 TLB configurations on each successive call. This
results in the previous PUD page being trampled when PMDs with an
overlapping PUD are initialized. This case was triggered by putting
persistent kmaps immediately below the fixmap range for highmem.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The function begins and ends with a read_lock. The latter is changed to a
read_unlock.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@locked@
expression E1;
position p;
@@
read_lock(E1@p,...);
@r exists@
expression x <= locked.E1;
expression locked.E1;
expression E2;
identifier lock;
position locked.p,p1,p2;
@@
*lock@p1 (E1@p,...);
... when != E1
when != \(x = E2\|&x\)
*lock@p2 (E1,...);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that the node 0 initialization code has been overhauled, kill off the
now obsolete setup_memory() bits.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The reserve_crashkernel() definition is in asm/kexec.h which is only
dragged in via linux/kexec.h if CONFIG_KEXEC is set. Just switch over to
asm/kexec.h unconditionally to fix up the build.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The minimum section size for the PMB is 16M, so just always error
out early if the specified size is too small. This permits us to
unconditionally call in to pmb_bolt_mapping() with variable sizes
without wasting a TLB and cache flush for the range.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This reworks much of the bootmem setup and initialization code allowing
us to get rid of duplicate work between the NUMA and non-NUMA cases. The
end result is that we end up with a much more flexible interface for
supporting more complex topologies (fake NUMA, highmem, etc, etc.) which
is entirely LMB backed. This is an incremental step for more NUMA work as
well as gradually enabling migration off of bootmem entirely.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Stuart Menefy