Impact: fix spurious IRQs
During irq migration, we send a low priority interrupt to the previous
irq destination. This happens in non interrupt-remapping case after interrupt
starts arriving at new destination and in interrupt-remapping case after
modifying and flushing the interrupt-remapping table entry caches.
This low priority irq cleanup handler can cleanup multiple vectors, as
multiple irq's can be migrated at almost the same time. While
there will be multiple invocations of irq cleanup handler (one cleanup
IPI for each irq migration), first invocation of the cleanup handler
can potentially cleanup more than one vector (as the first invocation can
see the requests for more than vector cleanup). When we cleanup multiple
vectors during the first invocation of the smp_irq_move_cleanup_interrupt(),
other vectors that are to be cleanedup can still be pending in the local
cpu's IRR (as smp_irq_move_cleanup_interrupt() runs with interrupts disabled).
When we are ready to unhook a vector corresponding to an irq, check if that
vector is registered in the local cpu's IRR. If so skip that cleanup and
do a self IPI with the cleanup vector, so that we give a chance to
service the pending vector interrupt and then cleanup that vector
allocation once we execute the lowest priority handler.
This fixes spurious interrupts seen when migrating multiple vectors
at the same time.
[ This is apparently possible even on conventional xapic, although to
the best of our knowledge it has never been seen. The stable
maintainers may wish to consider this one for -stable. ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: stable@kernel.org
Impact: fix possible race
save_mask_IO_APIC_setup() was using non atomic memory allocation while getting
called with interrupts disabled. Fix this by splitting this into two different
function. Allocation part save_IO_APIC_setup() now happens before
disabling interrupts.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
Clean up #ifdefs and replace them with helper functions.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: simplification
In the current code, for level triggered migration, we need to modify the
io-apic RTE with the update vector information, along with modifying interrupt
remapping table entry(IRTE) with vector and destination. This is to ensure that
remote IRR bit inthe IOAPIC RTE gets cleared when the cpu does EOI.
With this patch, for level triggered, we eliminate the io-apic RTE modification
(with the updated vector information), by using a virtual vector (io-apic pin
number). Real vector that is used for interrupting cpu will be coming from
the interrupt-remapping table entry. Trigger mode in the IRTE will always be
edge, and the actual level or edge trigger will be setup in the IO-APIC RTE.
So a level triggered interrupt will appear as an edge to the local apic
cpu but still as level to the IO-APIC.
With this change, level irq migration can be done by simply modifying
the interrupt-remapping table entry with out changing the io-apic RTE.
And as the interrupt appears as edge at the cpu, in addition to do the
local apic EOI, we need to do IO-APIC directed EOI to clear the remote
IRR bit in the IO-APIC RTE.
This simplies the irq migration in the presence of interrupt-remapping.
Idea-by: Rajesh Sankaran <rajesh.sankaran@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup, paranoia
We were not clearing the local APIC in clear_local_APIC() in the
presence of x2apic. Fix it.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: make kexec work with x2apic
disable_IO_APIC() gets called during crashdump aswell, which configures the
IO-APIC/LAPIC so that legacy interrupts can be delivered for the kexec'd kernel.
In the presence of interrupt-remapping, we need to change the
interrupt-remapping configuration aswell as modifying IO-APIC for virtual wire
B mode.
To keep things simple during the crash, use virtual wire A mode
(for which we don't need to touch io-apic and interrupt-remapping tables).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: interface augmentation (not yet used)
Enable fault handling flow for intr-remapping aswell. Fault handling
code now shared by both dma-remapping and intr-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
The setup code is mostly 16-bit code, but there is a small stub of
32-bit code at the end. Move the 32-bit code to a separate segment,
.text32, to avoid scrambling the disassembly.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: build fix with CONFIG_RELOCATABLE
Move _end into a dummy section, so that relocs.c will know it is a
relocatable symbol.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Impact: disambiguate real .bss variables from .brk storage
Add a .brk section after the .bss section. This has no effect
on the final vmlinux, but it more clearly distinguishes the space
taken by actual .bss symbols, and the variable space reserved
by .brk users.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Impact: bulletproofing, clarification
The brk reservation symbols are just there to document the amount
of space reserved by brk users in the final vmlinux file. Their
addresses are irrelevent, and using their addresses will cause
certain havok. Name them ".brk.NAME", which is a valid asm symbol
but C can't reference it; it also highlights their special
role in the symbol table.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Impact: Tighten bound to avoid masking errors
The definition of MAPPING_BEYOND_END was excessive; this has a nasty
tendency to mask bugs. We have learned over time that this kind of
bug hiding can cause some very strange errors. Therefore, tighten the
bound to only need to map the actual kernel area.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Impact: cleanup
ALLOCATOR_SLOP is a vestigial remain from when we used the
bootmem allocator to allocate the kernel's linear memory mapping.
Now we directly reserve pages from the e820 mapping, and no
longer require secondary structures to keep track of allocated
pages.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: crash fix
head_32.S needs to map the kernel itself, and enough space so
that mm/init.c can allocate space from the e820 allocator
for the linear map of low memory.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Don't boost at the addresses which are listed on exception tables,
because major page fault will occur on those addresses. In that case,
kprobes can not ensure that when instruction buffer can be freed since
some processes will sleep on the buffer.
kprobes-ia64 already has same check.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since we now set _PAGE_COHERENT in the Linux PTE we shouldn't be clearing
it out before we setup the SW TLB. Today all the SW TLB machines
(603/e300) that we support are non-SMP, however there are some errata on
some devices that cause us to set _PAGE_COHERENT via CPU_FTR_NEED_COHERENT.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
BestComm, a DMA engine in MPC52xx SoC, requires snooping when
CPU caches are enabled to work properly.
Adding CPU_FTR_NEED_COHERENT fixes NFS problems on MPC52xx machines
introduced by 'powerpc/mm: Fix handling of _PAGE_COHERENT in BAT setup
code' (sha1: 4c456a67f5).
Signed-off-by: Piotr Ziecik <kosmo@semihalf.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
In order for ntpd to correctly synchronize the clocks, the frequency of
the system clock must not be off by more than 500 ppm (or, put another
way, 1:2000), or ntpd will end up giving up on trying to synchronize
properly, and ends up reseting the clock in jumps instead.
The fast TSC PIT calibration sometimes failed this test - it was
assuming that the PIT reads always took about one microsecond each (2us
for the two reads to get a 16-bit timer), and that calibrating TSC to
the PIT over 15ms should thus be sufficient to get much closer than
500ppm (max 2us error on both sides giving 4us over 15ms: a 270 ppm
error value).
However, that assumption does not always hold: apparently some hardware
is either very much slower at reading the PIT registers, or there was
other noise causing at least one machine to get 700+ ppm errors.
So instead of using a fixed 15ms timing loop, this changes the fast PIT
calibration to read the TSC delta over the individual PIT timer reads,
and use the result to calculate the error bars on the PIT read timing
properly. We then successfully calibrate the TSC only if the maximum
error bars fall below 500ppm.
In the process, we also relax the timing to allow up to 25ms for the
calibration, although it can happen much faster depending on hardware.
Reported-and-tested-by: Jesper Krogh <jesper@krogh.cc>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During bootup, when we reprogram the PIT (programmable interval timer)
to start counting down from 0xffff in order to use it for the fast TSC
calibration, we should also make sure to delay a bit afterwards to allow
the PIT hardware to actually start counting with the new value.
That will happens at the next CLK pulse (1.193182 MHz), so the easiest
way to do that is to just wait at least one microsecond after
programming the new PIT counter value. We do that by just reading the
counter value back once - which will take about 2us on PC hardware.
Reported-and-tested-by: john stultz <johnstul@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Map unused registers at the end of DMA region at 64 MB to allow PCI masters
to cross the boundary when prefetching data from SDRAM.
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
This follows the ARM change from Aaro Koskinen:
When unmapping N pages (e.g. shared memory) the amount of TLB
flushes done can be (N*PAGE_SIZE/ZAP_BLOCK_SIZE)*N although it
should be N at maximum. With PREEMPT kernel ZAP_BLOCK_SIZE is 8
pages, so there is a noticeable performance penalty when
unmapping a large VMA and the system is spending its time in
flush_tlb_range().
The problem is that tlb_end_vma() is always flushing the full VMA
range. The subrange that needs to be flushed can be calculated by
tlb_remove_tlb_entry(). This approach was suggested by Hugh
Dickins, and is also used by other arches.
The speed increase is roughly 3x for 8M mappings and for larger
mappings even more.
Bits and peices are taken from the ARM patch as well as the existing
arch/um implementation that is quite similar.
The end result is a significant reduction in both partial and full TLB
flushes initiated through flush_tlb_range().
At the same time, the nommu implementation was broken, had a superfluous
cache flush, and subsequently would have triggered a BUG_ON() if a
code-path had triggered it. Tidy this up for correctness and provide a
nopped-out implementation there.
More background on the initial discussion can be found at:
http://marc.info/?t=123609820900002&r=1&w=2http://marc.info/?t=123660375800003&r=1&w=2
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Impact: don't trim e820 according to wrong mtrr
Ozan reports that his server emits strange warning.
it turns out the BIOS sets the MTRRs incorrectly.
Ignore those strange ranges, and don't trim e820,
just emit one warning about BIOS
Reported-by: Ozan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BEE1E7.7020706@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While harmless, PTEA has different semantics on these parts, and is only
used in extended TLB mode. Kill off the legacy support.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for extended ASIDs (up to 16-bits) on newer SH-X3 cores
that implement the PTAEX register and respective functionality. Presently
only the 65nm SH7786 (90nm only supports legacy 8-bit ASIDs).
The main change is in how the PTE is written out when loading the entry
in to the TLB, as well as in how the TLB entry is selectively flushed.
While SH-X2 extended mode splits out the memory-mapped U and I-TLB data
arrays for extra bits, extended ASID mode splits out the address arrays.
While we don't use the memory-mapped data array access, the address
array accesses are necessary for selective TLB flushes, so these are
implemented newly and replace the generic SH-4 implementation.
With this, TLB flushes in switch_mm() are almost non-existent on newer
parts.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
IRQ for sh_eth of sh7763rdp became multi handling.
Therefore, the IRQ number of sh_eth is changed, too.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for the ESPT-Giga (Ethernet Serial Parallel
Translator) SH7763-based reference board.
Board support is relatively sparse, presently supporting serial,
gigabit ethernet, USB host, and MTD.
More information (in Japanese) available at:
http://www.cente.jp/product/cente_hard/ESPT-Giga.html
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Impact: fix crash on VMI (VMware)
When we generate a call sequence for calling a paravirtualized
function, we presume that the generated code is "call *0xXXXXX",
which is a 6 byte opcode; this is larger than a normal
direct call, and so we can patch a direct call over it.
At the moment, however we give gcc enough rope to hang us by
putting the address in a register and generating a two byte
indirect-via-register call. Prevent this by explicitly
dereferencing the function pointer and passing it into the
asm as a constant.
This prevents crashes in VMI, as it cannot handle unpatchable
callsites.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Alok Kataria <akataria@vmware.com>
LKML-Reference: <49BEEDC2.2070809@goop.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
With arch/sh/drivers/dma/ always being built, the Dreamcast DMA engines
are being unconditionally built in, regardless of whether the DMA API is
enabled or not. This is a regression from previous behaviour, but there
is not much advantage in building them all in unconditionally regardless.
Add a new config option to make it optional, and update the only user of
it to reflect that.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
It is trivial to merge the non-MMU and MMU versions of siginfo.h.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of siginfo.h are not installed).
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The MMU version of unistd.h can be use on non-MMU platrorms as well.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of unistd.h are not installed).
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
It is trivial to merge the non-MMU and MMU versions of signal.h.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of signal.h are not installed).
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
It is trivial to merge the non-MMU and MMU versions of ptrace.h.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of ptrace.h are not installed).
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
The MMU version of setup.h can be used for all m68k platforms.
Without a single file "make headers_install" is broken for m68k
(since each of the sub-varients of setup.h are not installed).
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
When SuperH CPU has IRQ multi of DMAC, SH_DMA_IRQ_MULTI becomes enable.
The following CPU's are Multi IRQ of DMAC now.
- SH775X and SH7091
- SH776X
- SH7780
- SH7785
If SH_DMA_IRQ_MULTI becomes enable, dma-sh api driver is optimized
for Multi IRQ.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes a possible problem in the resume from
hibenration. It temporaneally saves the clk->rate on the
stack to avoid any possible change during the clk->set_parent(..)
call.
Signed-off-by: Francesco Virlinzi <francesco.virlinzi@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Improve the ap325 board code to allow the lcd panel
and backlight to be powered off.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch contains CONFIG_SUSPEND support to the SuperH
architecture. If enabled, SuperH Mobile processors will
register their suspend callbacks during boot.
To suspend, use "echo mem > /sys/power/state". To allow
wakeup, make sure "/sys/device/platform/../power/wakeup"
contains "enabled". Additional per-device driver patches
are most likely needed.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
