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git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6:
avr32: pm_standby low-power ram bug fix
avr32: Fix lockup after Java stack underflow in user mode
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git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: Fix rare boot build breakage
powerpc/spufs: Fix possible scheduling of a context to multiple SPEs
powerpc/spufs: Fix race for a free SPU
powerpc/spufs: Fix multiple get_spu_context()
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* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] 5241/1: provide ioremap_wc()
[ARM] omap: fix virtual vs physical address space confusions
[ARM] remove unused #include <version.h>
[ARM] omap: fix build error in ohci-omap.c
[ARM] omap: fix gpio.c build error
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc64: Prevent sparc64 from invoking irq handlers on offline CPUs
sparc64: Fix IPI call locking.
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A make -j20 powerpc kernel build broke a couple of months ago saying:
In file included from arch/powerpc/boot/gunzip_util.h:13,
from arch/powerpc/boot/prpmc2800.c:21:
arch/powerpc/boot/zlib.h:85: error: expected ‘:’, ‘,’, ‘;’, ‘}’ or ‘__attribute__’ before ‘*’ token
arch/powerpc/boot/zlib.h:630: warning: type defaults to ‘int’ in declaration of ‘Byte’
arch/powerpc/boot/zlib.h:630: error: expected ‘;’, ‘,’ or ‘)’ before ‘*’ token
It happened again yesterday: too rare for me to confirm the fix, but
it looks like the list of dependants on gunzip_util.h was incomplete.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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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>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: cpu_init(): fix memory leak when using CPU hotplug
x86: pda_init(): fix memory leak when using CPU hotplug
x86, xen: Use native_pte_flags instead of native_pte_val for .pte_flags
x86: move mtrr cpu cap setting early in early_init_xxxx
x86: delay early cpu initialization until cpuid is done
x86: use X86_FEATURE_NOPL in alternatives
x86: add NOPL as a synthetic CPU feature bit
x86: boot: stub out unimplemented CPU feature words
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
clocksource, acpi_pm.c: check for monotonicity
clocksource, acpi_pm.c: use proper read function also in errata mode
ntp: fix calculation of the next jiffie to trigger RTC sync
x86: HPET: read back compare register before reading counter
x86: HPET fix moronic 32/64bit thinko
clockevents: broadcast fixup possible waiters
HPET: make minimum reprogramming delta useful
clockevents: prevent endless loop lockup
clockevents: prevent multiple init/shutdown
clockevents: enforce reprogram in oneshot setup
clockevents: prevent endless loop in periodic broadcast handler
clockevents: prevent clockevent event_handler ending up handler_noop
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* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Probe initrd header only if explicitly specified
[MIPS] TX39xx: Add missing local_flush_icache_range initialization
[MIPS] TXx9: Fix txx9_pcode initialization
[MIPS] Fix WARNING: at kernel/smp.c:290
[MIPS] Fix data bus error recovery
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Exception stacks are allocated each time a CPU is set online.
But the allocated space is never freed. Thus with one CPU hotplug
offline/online cycle there is a memory leak of 24K (6 pages) for
a CPU.
Fix is to allocate exception stacks only once -- when the CPU is
set online for the first time.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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pda->irqstackptr is allocated whenever a CPU is set online.
But it is never freed. This results in a memory leak of 16K
for each CPU offline/online cycle.
Fix is to allocate pda->irqstackptr only once.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Using native_pte_val triggers the BUG_ON() in the paravirt_ops
version of pte_flags().
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Krzysztof Helt found MTRR is not detected on k6-2
root cause:
we moved mtrr_bp_init() early for mtrr trimming,
and in early_detect we only read the CPU capability from cpuid,
so some cpu doesn't have that bit in cpuid.
So we need to add early_init_xxxx to preset those bit before mtrr_bp_init
for those earlier cpus.
this patch is for v2.6.27
Reported-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Move early cpu initialization after cpu early get cap so the
early cpu initialization can fix up cpu caps.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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This patch provides an ARM implementation of ioremap_wc().
We use different page table attributes depending on which CPU we
are running on:
- Non-XScale ARMv5 and earlier systems: The ARMv5 ARM documents four
possible mapping types (CB=00/01/10/11). We can't use any of the
cached memory types (CB=10/11), since that breaks coherency with
peripheral devices. Both CB=00 and CB=01 are suitable for _wc, and
CB=01 (Uncached/Buffered) allows the hardware more freedom than
CB=00, so we'll use that.
(The ARMv5 ARM seems to suggest that CB=01 is allowed to delay stores
but isn't allowed to merge them, but there is no other mapping type
we can use that allows the hardware to delay and merge stores, so
we'll go with CB=01.)
- XScale v1/v2 (ARMv5): same as the ARMv5 case above, with the slight
difference that on these platforms, CB=01 actually _does_ allow
merging stores. (If you want noncoalescing bufferable behavior
on Xscale v1/v2, you need to use XCB=101.)
- Xscale v3 (ARMv5) and ARMv6+: on these systems, we use TEXCB=00100
mappings (Inner/Outer Uncacheable in xsc3 parlance, Uncached Normal
in ARMv6 parlance).
The ARMv6 ARM explicitly says that any accesses to Normal memory can
be merged, which makes Normal memory more suitable for _wc mappings
than Device or Strongly Ordered memory, as the latter two mapping
types are guaranteed to maintain transaction number, size and order.
We use the Uncached variety of Normal mappings for the same reason
that we can't use C=1 mappings on ARMv5.
The xsc3 Architecture Specification documents TEXCB=00100 as being
Uncacheable and allowing coalescing of writes, which is also just
what we need.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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After fixing the u32 thinko I sill had occasional hickups on ATI chipsets
with small deltas. There seems to be a delay between writing the compare
register and the transffer to the internal register which triggers the
interrupt. Reading back the value makes sure, that it hit the internal
match register befor we compare against the counter value.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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We use the HPET only in 32bit mode because:
1) some HPETs are 32bit only
2) on i386 there is no way to read/write the HPET atomic 64bit wide
The HPET code unification done by the "moron of the year" did
not take into account that unsigned long is different on 32 and
64 bit.
This thinko results in a possible endless loop in the clockevents
code, when the return comparison fails due to the 64bit/332bit
unawareness.
unsigned long cnt = (u32) hpet_read() + delta can wrap over 32bit.
but the final compare will fail and return -ETIME causing endless
loops.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Use X86_FEATURE_NOPL to determine if it is safe to use P6 NOPs in
alternatives. Also, replace table and loop with simple if statement.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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The long noops ("NOPL") are supposed to be detected by family >= 6.
Unfortunately, several non-Intel x86 implementations, both hardware
and software, don't obey this dictum. Instead, probe for NOPL
directly by executing a NOPL instruction and see if we get #UD.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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The CPU feature detection code in the boot code is somewhat minimal,
and doesn't include all possible CPUID words. In particular, it
doesn't contain the code for CPU feature words 2 (Transmeta),
3 (Linux-specific), 5 (VIA), or 7 (scattered). Zero them out, so we
can still set those bits as known at compile time; in particular, this
allows creating a Linux-specific NOPL flag and have it required (and
therefore resolvable at compile time) in 64-bit mode.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: add io delay quirk for Presario F700
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* git://git.infradead.org/~dwmw2/dwmw2-2.6.27:
Revert "[ARM] use the new byteorder headers"
Fix conditional export of kvh.h and a.out.h to userspace.
[MTD] [NAND] tmio_nand: fix base address programming
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git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* 'sh/for-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
i2c: fix i2c-sh_mobile timing issues
sh64: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
sh: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
sh: fix semtimedop syscall
sh: update AP325RXA defconfig
sh: update Migo-R defconfig
sh: fix platform_resource_setup_memory() section mismatch
sh: fix kexec entry point for crash kernels
sh: crash kernel resource fix
sh: fix ptrace_64.c:user_disable_single_step()
sh64: re-add the __strnlen_user() prototype
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Currently init_initrd() probes initrd header at the last page of kernel
image, but it is valid only if addinitrd was used. If addinitrd was not
used, the area contains garbage so probing there might misdetect initrd
header (magic number is not strictly robust).
This patch introduces CONFIG_PROBE_INITRD_HEADER to explicitly enable this
probing.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Commmit 59e39ecd933ba49eb6efe84cbfa5597a6c9ef18a ("Fix WARNING: at
kernel/smp.c:290") introduced local_flush_icache_range but lacks
initialization for some TX39 case.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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The txx9_pcode variable was introduced in commit
fe1c2bc64f65003b39f331a8e4b0d15b235a4afd ("TXx9: Add 64-bit support")
but was not initialized properly.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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trap_init issues flush_icache_range(), which uses ipi functions to
get icache flushing done on all cpus. But this is done before interrupts
are enabled and caused WARN_ON messages. This changeset introduces
a new local_flush_icache_range() and uses it before interrupts (and
additional CPUs) are enabled to avoid this problem.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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With -ffunction-section the entries in __dbe_table aren't no longer
sorted, so the lookup of exception addresses in do_be() failed for
some addresses. To avoid this we now sort __dbe_table.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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This reverts commit ae82cbfc8beaa69007aa09966d3983ac938c3577. It
needs the new byteorder headers to be exported to userspace, and
they aren't yet -- and probably shouldn't be, at this point in the
2.6.27 release cycle (or ever, for that matter).
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The minimum reprogramming delta was hardcoded in HPET ticks,
which is stupid as it does not work with faster running HPETs.
The C1E idle patches made this prominent on AMD/RS690 chipsets,
where the HPET runs with 25MHz. Set it to 5us which seems to be
a reasonable value and fixes the problems on the bug reporters
machines. We have a further sanity check now in the clock events,
which increases the delta when it is not sufficient.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Tested-by: Dmitry Nezhevenko <dion@inhex.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Follows the SH change.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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This patch fixes a problem within the SH implementation of resume_kernel code,
that implements in assembly the bulk of preempt_schedule_irq function without
taking care of the extra code needed to handle the BKL preemptible.
The patch basically consists of removing this asm code and calling the common
C implementation (see kernel/sched.c) as other archs do.
Another change is the missing 'cli' macro invocation at the beginning of
the resume_kernel.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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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>
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Commit 8d5636fbca202f61fdb808fc9e20c0142291d802 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>
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mcbsp is confused as to what takes a physical or virtual address.
Fix the two instances where it gets it wrong.
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The driver(s) below do not use LINUX_VERSION_CODE nor KERNEL_VERSION.
arch/arm/plat-mxc/clock.c
This patch removes the said #include <version.h>.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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When calibration against PIT fails, the warning that we print is misleading.
In a virtualized environment the VM may get descheduled while calibration
or, the check in PIT calibration may fail due to other virtualization
overheads.
The warning message explicitly assumes that calibration failed due to SMI's
which may not be the case. Change that to something proper.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: Fix for getting CPU number in power_save_ppc32_restore()
powerpc: Fix build error with 64K pages and !hugetlbfs
powerpc: Work around gcc's -fno-omit-frame-pointer bug
powerpc: Make sure _etext is after all kernel text
powerpc: Only make kernel text pages of linear mapping executable
powerpc: Fix uninitialised variable in VSX alignment code
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Manually adding "io_delay=0xed" fixes system lockups in ioapic
mode on this machine.
System Information
Manufacturer: Hewlett-Packard
Product Name: Presario F700 (KA695EA#ABF)
Base Board Information
Manufacturer: Quanta
Product Name: 30D3
Reference:
https://bugzilla.redhat.com/show_bug.cgi?id=459546
Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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The TSC calibration function is still very complicated, but this makes
it at least a little bit less so by moving the PIT part out into a
helper function of its own.
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-of-by: Linus Torvalds <torvalds@linux-foundation.org>
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The calculation to get TI_CPU based off of SPRG3 was just plain wrong,
meaning that we were getting garbage for the CPU number on 6xx/G3/G4
based SMP boxes in this code.
Just offset off the stack pointer (to get to thread_info) like all the
other references to TI_CPU do.
This was pointed out by Chen Gong <G.Chen@freescale.com>
[paulus@samba.org - use rlwinm r12,r11,... instead of
rlwinm r12,r1,...; tophys()]
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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HAVE_ARCH_UNMAPPED_AREA and HAVE_ARCH_UNMAPPED_AREA_TOPDOWN must
be defined whenever CONFIG_PPC_MM_SLICES is enabled, not just when
CONFIG_HUGETLB_PAGE is. They used to be always defined together but
this is no longer the case since 3a8247cc2c856930f34eafce33f6a039227ee175
("powerpc: Only demote individual slices rather than whole process").
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This bug is causing random crashes
(http://bugzilla.kernel.org/show_bug.cgi?id=11414).
-fno-omit-frame-pointer is only needed on powerpc when -pg is also
supplied, and there is a gcc bug that causes incorrect code generation
on 32-bit powerpc when -fno-omit-frame-pointer is used---it uses stack
locations below the stack pointer, which is not allowed by the ABI
because those locations can and sometimes do get corrupted by an
interrupt.
This ensures that CONFIG_FRAME_POINTER is only selected by ftrace.
When CONFIG_FTRACE is enabled we also pass -mno-sched-epilog to work
around the gcc codegen bug.
Patch based on work by:
Andreas Schwab <schwab@suse.de>
Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This makes core_kernel_text() (and therefore kernel_text_address())
return the correct result. Currently all the __devinit routines (at
least) will not be considered to be kernel text.
This is just a quick fix for 2.6.27 - hopefully we will be able to fix
this better in 2.6.28.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Commit bc033b63bbfeb6c4b4eb0a1d083c650e4a0d2af8 ("powerpc/mm: Fix
attribute confusion with htab_bolt_mapping()") moved the check for
whether we should make pages of the linear mapping executable from
htab_bolt_mapping into its callers, including htab_initialize.
A side-effect of this is that the decision is now made once for
each contiguous section in the LMB array rather than for each page
individually. This can often mean that the whole of the linear
mapping ends up being executable.
This reverts to the previous behaviour, where individual pages are
checked for being part of the kernel text or not, by moving the check
back down into htab_bolt_mapping.
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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This fixes an uninitialised variable in the VSX alignment code. It can
cause warnings from GCC (noticed with gcc-4.1.1). Gcc is actually
correct in this instance, and this bug could cause the alignment
interrupt handler to send a SIGSEGV to the process on a legitimate
access.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
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Make sparc64 refrain from clearing a given to-be-offlined CPU's bit in the
cpu_online_mask until it has processed pending irqs. This change
prevents other CPUs from being blindsided by an apparently offline CPU
nevertheless changing globally visible state.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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arch/arm/plat-omap/gpio.c: In function '_omap_gpio_init':
arch/arm/plat-omap/gpio.c:1492: error: 'omap_mpuio_device' undeclared (first use in this function)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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When I switched sparc64 over to the generic helpers for
smp_call_function(), I didn't convert the dinky call_lock
we had.
Use ipi_call_lock() and ipi_call_unlock().
Signed-off-by: David S. Miller <davem@davemloft.net>
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Larry Finger reported at http://lkml.org/lkml/2008/9/1/90:
An ancient laptop of mine started throwing errors from b43legacy when
I started using 2.6.27 on it. This has been bisected to commit bfc0f59
"x86: merge tsc calibration".
The unification of the TSC code adopted mostly the 64bit code, which
prefers PMTIMER/HPET over the PIT calibration.
Larrys system has an AMD K6 CPU. Such systems are known to have
PMTIMER incarnations which run at double speed. This results in a
miscalibration of the TSC by factor 0.5. So the resulting calibrated
CPU/TSC speed is half of the real CPU speed, which means that the TSC
based delay loop will run half the time it should run. That might
explain why the b43legacy driver went berserk.
On the other hand we know about systems, where the PIT based
calibration results in random crap due to heavy SMI/SMM
disturbance. On those systems the PMTIMER/HPET based calibration logic
with SMI detection shows better results.
According to Alok also virtualized systems suffer from the PIT
calibration method.
The solution is to use a more wreckage aware aproach than the current
either/or decision.
1) reimplement the retry loop which was dropped from the 32bit code
during the merge. It repeats the calibration and selects the lowest
frequency value as this is probably the closest estimate to the real
frequency
2) Monitor the delta of the TSC values in the delay loop which waits
for the PIT counter to reach zero. If the maximum value is
significantly different from the minimum, then we have a pretty safe
indicator that the loop was disturbed by an SMI.
3) keep the pmtimer/hpet reference as a backup solution for systems
where the SMI disturbance is a permanent point of failure for PIT
based calibration
4) do the loop iteration for both methods, record the lowest value and
decide after all iterations finished.
5) Set a clear preference to PIT based calibration when the result
makes sense.
The implementation does the reference calibration based on
HPET/PMTIMER around the delay, which is necessary for the PIT anyway,
but keeps separate TSC values to ensure the "independency" of the
resulting calibration values.
Tested on various 32bit/64bit machines including Geode 266Mhz, AMD K6
(affected machine with a double speed pmtimer which I grabbed out of
the dump), Pentium class machines and AMD/Intel 64 bit boxen.
Bisected-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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