Send async page fault to a PV guest if it accesses swapped out memory.
Guest will choose another task to run upon receiving the fault.

Allow async page fault injection only when guest is in user mode since
otherwise guest may be in non-sleepable context and will not be able
to reschedule.

Vcpu will be halted if guest will fault on the same page again or if
vcpu executes kernel code.
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

When async PF capability is detected hook up special page fault handler
that will handle async page fault events and bypass other page faults to
regular page fault handler. Also add async PF handling to nested SVM
emulation. Async PF always generates exit to L1 where vcpu thread will
be scheduled out until page is available.
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Enable async PF in a guest if async PF capability is discovered.
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Guest enables async PF vcpu functionality using this MSR.
Reviewed-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Async PF also needs to hook into smp_prepare_boot_cpu so move the hook
into generic code.
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Keep track of memslots changes by keeping generation number in memslots
structure. Provide kvm_write_guest_cached() function that skips
gfn_to_hva() translation if memslots was not changed since previous
invocation.
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

When page is swapped in it is mapped into guest memory only after guest
tries to access it again and generate another fault. To save this fault
we can map it immediately since we know that guest is going to access
the page. Do it only when tdp is enabled for now. Shadow paging case is
more complicated. CR[034] and EFER registers should be switched before
doing mapping and then switched back.
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

If a guest accesses swapped out memory do not swap it in from vcpu thread
context. Schedule work to do swapping and put vcpu into halted state
instead.

Interrupts will still be delivered to the guest and if interrupt will
cause reschedule guest will continue to run another task.

[avi: remove call to get_user_pages_noio(), nacked by Linus; this
      makes everything synchrnous again]
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The only bit of EFER that affects the mmu is NX, and this is already
accounted for (LME only takes effect when changing cr0).

Based on a patch by Hillf Danton.
Signed-off-by: NAvi Kivity <avi@redhat.com>

isr_ack is never initialized.  So, until the first PIC reset, interrupts
may fail to be injected.  This can cause Windows XP to fail to boot, as
reported in the fallout from the fix to
https://bugzilla.kernel.org/show_bug.cgi?id=21962.
Reported-and-tested-by: NNicolas Prochazka <prochazka.nicolas@gmail.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We use the physical address instead of the base gfn for the four
PAE page directories we use in unpaged mode.  When the guest accesses
an address above 1GB that is backed by a large host page, a BUG_ON()
in kvm_mmu_set_gfn() triggers.

Resolves: https://bugzilla.kernel.org/show_bug.cgi?id=21962Reported-and-tested-by: NNicolas Prochazka <prochazka.nicolas@gmail.com>
KVM-Stable-Tag.
Signed-off-by: NAvi Kivity <avi@redhat.com>

The current tile rt_sigreturn() syscall pattern uses the common idiom
of loading up pt_regs with all the saved registers from the time of
the signal, then anticipating the fact that we will clobber the ABI
"return value" register (r0) as we return from the syscall by setting
the rt_sigreturn return value to whatever random value was in the pt_regs
for r0.

However, this breaks in our 64-bit kernel when running "compat" tasks,
since we always sign-extend the "return value" register to properly
handle returned pointers that are in the upper 2GB of the 32-bit compat
address space.  Doing this to the sigreturn path then causes occasional
random corruption of the 64-bit r0 register.

Instead, we stop doing the crazy "load the return-value register"
hack in sigreturn.  We already have some sigreturn-specific assembly
code that we use to pass the pt_regs pointer to C code.  We extend that
code to also set the link register to point to a spot a few instructions
after the usual syscall return address so we don't clobber the saved r0.
Now it no longer matters what the rt_sigreturn syscall returns, and the
pt_regs structure can be cleanly and completely reloaded.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>

Previously we were just setting up the "tp" register in the
new task as started by clone() in libc.  However, this is not
quite right, since in principle a signal might be delivered to
the new task before it had its TLS set up.  (Of course, this race
window still exists for resetting the libc getpid() cached value
in the new task, in principle.  But in any case, we are now doing
this exactly the way all other architectures do it.)

This change is important for 2.6.37 since the tile glibc we will
be submitting upstream will not set TLS in user space any more,
so it will only work on a kernel that has this fix.  It should
also be taken for 2.6.36.x in the stable tree if possible.
Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>
Cc: stable <stable@kernel.org>

Seen with malta_defconfig on Linus' tree:

  CC      arch/mips/mm/sc-mips.o
arch/mips/mm/sc-mips.c: In function 'mips_sc_is_activated':
arch/mips/mm/sc-mips.c:77: error: 'config2' undeclared (first use in this function)
arch/mips/mm/sc-mips.c:77: error: (Each undeclared identifier is reported only once
arch/mips/mm/sc-mips.c:77: error: for each function it appears in.)
arch/mips/mm/sc-mips.c:81: error: 'tmp' undeclared (first use in this function)
make[2]: *** [arch/mips/mm/sc-mips.o] Error 1
make[1]: *** [arch/mips/mm] Error 2
make: *** [arch/mips] Error 2

[Ralf: Cosmetic changes to minimize the number of arguments passed to
mips_sc_is_activated]
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/1752/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This prevents allocation of the last 2MB before 4GB.

The experiment described here shows Windows 7 ignoring the last 1MB:
https://bugzilla.kernel.org/show_bug.cgi?id=23542#c27

This patch ignores the top 2MB instead of just 1MB because H. Peter Anvin
says "There will be ROM at the top of the 32-bit address space; it's a fact
of the architecture, and on at least older systems it was common to have a
shadow 1 MiB below."
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

When we allocate address space, e.g., to assign it to a PCI device, don't
allocate anything mentioned in the BIOS E820 memory map.

On recent machines (2008 and newer), we assign PCI resources from the
windows described by the ACPI PCI host bridge _CRS.  On many Dell
machines, these windows overlap some E820 reserved areas, e.g.,

    BIOS-e820: 00000000bfe4dc00 - 00000000c0000000 (reserved)
    pci_root PNP0A03:00: host bridge window [mem 0xbff00000-0xdfffffff]

If we put devices at 0xbff00000, they don't work, probably because
that's really RAM, not I/O memory.  This patch prevents that by removing
the 0xbfe4dc00-0xbfffffff area from the "available" resource.

I'm not very happy with this solution because Windows solves the problem
differently (it seems to ignore E820 reserved areas and it allocates
top-down instead of bottom-up; details at comment 45 of the bugzilla
below).  That means we're vulnerable to BIOS defects that Windows would not
trip over.  For example, if BIOS described a device in ACPI but didn't
mention it in E820, Windows would work fine but Linux would fail.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=16228Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This implements arch_remove_reservations() so allocate_resource() can
avoid any arch-specific reserved areas.  This currently just avoids the
BIOS area (the first 1MB), but could be used for E820 reserved areas if
that turns out to be necessary.

We previously avoided this area in pcibios_align_resource().  This patch
moves the test from that PCI-specific path to a generic path, so *all*
resource allocations will avoid this area.
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This reverts commit dc9887dc.
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This reverts commit 1af3c2e4.
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

As PControl G20 is a carrier board for the Stamp9G20 SoM, some code can
be shared. Therefore board-stamp9g20.c is refactored to allow reusing the
SoM initialization and board-pcontrol-g20.c is modified to use it.
Signed-off-by: NChristian Glindkamp <christian.glindkamp@taskit.de>
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>

The uhpck clock should be divided from the utmi clock, not its parent
(main). This change is mostly cosmetic as the uhpck rate value is not
used anywhere except for the debugfs clock output.
Signed-off-by: NRyan Mallon <ryan@bluewatersys.com>
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>

For huge page support with base page size of 16K or 32K, we have to
increase the MAX_ORDER so that huge pages can be allocated.

[Ralf: I don't think a user should have to configure obscure constants like
this but for the time being this will have to suffice.]
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1685/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

I am about to commit:

http://sourceware.org/ml/binutils/2010-10/msg00033.html

that fixes a problem with the LD/SD macro currently implemented by GAS for
the o32 ABI in an inconsistent way.  This is best illustrated with a
simple program, which I'm copying here from the message above for easier
reference:

$ cat ld.s
	ld	$5,32767($4)
	ld	$5,32768($4)

This gets assebled into the following output:

$ mips-linux-as -32 -mips3 -o ld.o ld.s
$ mips-linux-objdump -d ld.o

ld.o:     file format elf32-tradbigmips

Disassembly of section .text:

00000000 <.text>:
   0:	dc857fff 	ld	a1,32767(a0)
   4:	3c010001 	lui	at,0x1
   8:	00810821 	addu	at,a0,at
   c:	8c258000 	lw	a1,-32768(at)
  10:	8c268004 	lw	a2,-32764(at)
	...

Oops!

 The GAS fix makes the macro behave in a consistent way and pairs of LW/SW
instructions to be output as appropriate regardless of the size of the
offset associated with the address used.  The machine instruction is still
available, but to reach it macros have to be disabled first.  This has a
side effect of requiring the use of a machine-addressable memory operand.

 As some platforms require 64-bit operations for accesses to some I/O
registers LD/SD instructions are used in a couple of places in Linux
regardless of the ABI selected.  Here's a fix for some pieces of code
affected I've been able to track down.  The fix should be backwards
compatible with all supported binutils releases in existence and can be
used as a reference for any other places or off-tree code.  The use of the
"R" constraint guarantees a machine-addressable operand.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1680/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

In commit 7d172bfe ("Alchemy: Add UART PM methods") I introduced
platform PM methods which call a function of the 8250 driver;
this patch works around link failures when the kernel is built
without 8250 support.
Signed-off-by: NManuel Lauss <manuel.lauss@googlemail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/1737/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This fixes IP22 and IP28 build errors.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Some devices like the Netgear WGT634U are using ttyS1 for default console
output. We should switch to that console if it was given in the kernel_args
parameters.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1848/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Instead of writing own function for parsing the mac address we now
use sscanf.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1847/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Fill the sprom with all available values from the nvram. Most of these
new values are needed for the b43 or b43legacy driver.

Parts of this patch have been in OpenWRT for a long time and were written
by Michael Buesch.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1846/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The config options read out here are not stored in CFE but only in NVRAM on
the devices. Remove reading from CFE and only access the NVRAM.  Reading out
CFE does not harm but is useless here.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1845/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The totalsize field was be32. And the reserve bootmem would cause failure.
Signed-off-by: NThomas Chou <thomas@wytron.com.tw>
To: devicetree-discuss@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: grant.likely@secretlab.ca
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Dezhong Diao <dediao@cisco.com>
Patchwork: https://patchwork.linux-mips.org/patch/1838/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Consider the following test case:

write_c0_compare(read_c0_count());

Even if the counter doesn't increment during execution, this might not
generate an interrupt until the counter wraps around.  The CPU may
perform the comparison each time CP0 COUNT increments, not when CP0
COMPARE is written.

If mips_next_event() is called with a very small delta, and CP0 COUNT
increments during the calculation of "cnt += delta", it is possible
that CP0 COMPARE will be written with the current value of CP0 COUNT.
If this is detected, the function should return -ETIME, to indicate
that the interrupt might not have actually gotten scheduled.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1836/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

BCM4710 uses the BMIPS32 core (like BCM6345), not the MIPS 4Kc core as
was previously believed.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Tested-by: NAlexandros C. Couloumbis <alex@ozo.com>
Patchwork: https://patchwork.linux-mips.org/patch/1837/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

As part the ASoC multi-component patch (commit f0fba2ad) the jz4740 pcm
driver was renamed to 'jz4740-pcm-audio'. Adjust the device name
accordingly.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1770/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

partial_fixup is used in noreorder block.

Separating two consecutive loads can save one cycle on processors with
GPR intrelock and can fix load-use on processors that need a load delay slot.

Also do so for fwd_fixup.

[Ralf: Only R2000/R3000 class processors are lacking the the load-user
interlock and even some of those got it retrofitted.  With R2000/R3000
being fairly uncommon these days the impact of this bug should be minor.]
Signed-off-by: NTony Wu <tung7970@gmail.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1768/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We were unconditionally sending SIGBUS with an empty siginfo on FP
emulator faults.  This differs from what happens when real floating
point hardware would get a fault.

For most faults we need to send SIGSEGV with the faulting address
filled in in the struct siginfo.
Reported-by: NCamm Maguire <camm@maguirefamily.org>
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Camm Maguire <camm@maguirefamily.org>
Patchwork: https://patchwork.linux-mips.org/patch/1727/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

TNETD7200 run their CPU clock faster than the default CPU clock we assume.
In order to have the correct loops per jiffies settings, initialize clocks right
before setting mips_hpt_frequency. As a side effect, we can no longer use
msleep in clocks.c which requires other parts of the kernel to be initialized,
so replace these with mdelay.
Signed-off-by: NFlorian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1749/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NFlorian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1748/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Recent changes to CONFIG_GENERIC_HARDIRQS have caused us to start getting:

warning: (SMP && SYS_SUPPORTS_SMP) selects IRQ_PER_CPU which has unmet direct dependencies (HAVE_GENERIC_HARDIRQS)

Rearranging our Kconfig quiets the message.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Patchwork: https://patchwork.linux-mips.org/patch/1757/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/alchemy/devboards/prom.c: In function 'prom_init':
arch/mips/alchemy/devboards/prom.c:60: error: ignoring return value of
'strict_strtoul', declared with attribute warn_unused_result
Signed-off-by: NYoichi Yuasa <yuasa@linux-mips.org>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/1761/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>