The logic to detect if the irq stack was already in use with
raw_spin_trylock() is wrong, because it will generate a "trylock failure
on UP" error message with CONFIG_SMP=n and CONFIG_DEBUG_SPINLOCK=y.

arch_spin_trylock() can't be used either since in the CONFIG_SMP=n case
no atomic protection is given and we are reentrant here. A mutex didn't
worked either and brings more overhead by turning off interrupts.

So, let's use the fastest path for parisc which is the ldcw instruction.

Counting how often the irq stack was used is pretty useless, so just
drop this piece of code.
Signed-off-by: NHelge Deller <deller@gmx.de>

The get_stack_use_cr30 and get_stack_use_r30 macros allocate a stack
frame for external interrupts and interruptions requiring a stack frame.
They are currently not reentrant in that they save register context
before the stack is set or adjusted.

I have observed a number of system crashes where there was clear
evidence of stack corruption during interrupt processing, and as a
result register corruption. Some interruptions can still occur during
interruption processing, however external interrupts are disabled and
data TLB misses don't occur for absolute accesses. So, it's not entirely
clear what triggers this issue. Also, if an interruption occurs when
Q=0, it is generally not possible to recover as the shadowed registers
are not copied.

The attached patch reworks the get_stack_use_cr30 and get_stack_use_r30
macros to allocate stack before doing register saves. The new code is a
couple of instructions shorter than the old implementation. Thus, it's
an improvement even if it doesn't fully resolve the stack corruption
issue. Based on limited testing, it improves SMP system stability.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

Show number of floating point assistant and unaligned access fixup
handler in /proc/interrupts file.
Signed-off-by: NHelge Deller <deller@gmx.de>

additionally clean up some whitespaces & tabs.
Signed-off-by: NHelge Deller <deller@gmx.de>

Signed-off-by: NHelge Deller <deller@gmx.de>

Recent commit e61133dd added support
for a new firmware feature to force an adapter to use 32 bit MSIs.
However, this firmware is not available for all systems. The hack below
allows devices needing 32 bit MSIs to work on these systems as well.
It is careful to only enable this on Gen2 slots, which should limit
this to configurations where this hack is needed and tested to work.

[Small change to factor out the hack into a separate function -- BenH]
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The zImage.epapr wrapper allows to use zImages when booting via a flat
device-tree which can be used on powernv.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This moves the quirk itself to pci_64.c as to get built on all ppc64
platforms (the only ones with a pci_dn), factors the two implementations
of get_pdn() into a single pci_get_dn() and use the quirk to do 32-bit
MSIs on IODA based powernv platforms.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

In commit 9353374b "Context switch the new EBB SPRs" we added support for
context switching some new EBB SPRs. However despite four of us signing
off on that patch we missed some. To be fair these are not actually new
SPRs, but they are now potentially user accessible so need to be context
switched.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We use two flags, one to indicate an invalidation is needed after
creating a new entry and one to indicate an invalidation is needed
after removing an entry. However we were testing the wrong flag
in the remove case.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The message is only meant to be displayed if resource 0 is empty,
but was displayed if any is.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The TLB has 512 congruence classes (2048 entries 4 way set associative)
while P7 had 128
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

As suggested by David Howells <dhowells@redhat.com>, use
asm-generic/param.h and uapi/asm-generic/param.h for AVR32.

It also fixes building warnings caused by redefinitions of HZ:
In file included from /ws/linux/kernel/linux.git/include/uapi/linux/param.h:4,
                 from include/linux/timex.h:63,
                 from include/linux/jiffies.h:8,
                 from include/linux/ktime.h:25,
                 from include/linux/timer.h:5,
                 from include/linux/workqueue.h:8,
                 from include/linux/srcu.h:34,
                 from include/linux/notifier.h:15,
                 from include/linux/memory_hotplug.h:6,
                 from include/linux/mmzone.h:777,
                 from include/linux/gfp.h:4,
                 from arch/avr32/mm/init.c:10:
/ws/linux/kernel/linux.git/arch/avr32/include/asm/param.h:6:1: warning: "HZ" redefined
In file included from /ws/linux/kernel/linux.git/arch/avr32/include/asm/param.h:4,
                 from /ws/linux/kernel/linux.git/include/uapi/linux/param.h:4,
                 from include/linux/timex.h:63,
                 from include/linux/jiffies.h:8,
                 from include/linux/ktime.h:25,
                 from include/linux/timer.h:5,
                 from include/linux/workqueue.h:8,
                 from include/linux/srcu.h:34,
                 from include/linux/notifier.h:15,
                 from include/linux/memory_hotplug.h:6,
                 from include/linux/mmzone.h:777,
                 from include/linux/gfp.h:4,
                 from arch/avr32/mm/init.c:10:
/ws/linux/kernel/linux.git/arch/avr32/include/uapi/asm/param.h:6:1: warning: this is the location of the previous definition
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHans-Christian Egtvedt <egtvedt@samfundet.no>

As a relatively new ABI, N64 only had getdents syscall while other modern
architectures have getdents64.

This was noticed when Python 3.3 shifted to the latter one for aarch64.

[ralf@linux-mips.org: The history of getdents64 is a little complicated.
Commit 1a1d77dd589de5a567fa95e36aa6999c704ceca4 [Merge with 2.4.0-test7.]
added N64 getdents(2) to arch/mips64/kernel/scall_64.S as syscall 5213,
then dropped again in 578720675c44e54e8aa7c68f6dce59ed37ce3d3b [Overhaul
of the 64-bit syscall interface.  Now heritage free.] for 2.5.18 in 2002.]
Signed-off-by: NAron Xu <aron@debian.org>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5285/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Fix to check double free of insn_slot at arch_remove_kprobe
as other arches do.
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Maneesh Soni <manesoni@cisco.com>
Cc: Victor Kamensky <kamensky@cisco.com>
Cc: linux-mips@linux-mips.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: yrl.pp-manager.tt@hitachi.com
Cc: systemtap@sourceware.org
Patchwork: https://patchwork.linux-mips.org/patch/5293/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

- As suggested by Gleb, wrap calls to gfn_to_pfn() with srcu_read_lock/unlock().
  Memory slots should be acccessed from a SRCU read section.
- kvm_mips_map_page() now returns an error code to it's callers, instead of
  calling panic() if it cannot find a mapping for a particular gfn.
Signed-off-by: NSanjay Lal <sanjayl@kymasys.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Signed-off-by: NSanjay Lal <sanjayl@kymasys.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

local_irq_enable() may expand into very different code, so it rather should
stay in C.  Also this keeps the assembler code size constant which keeps
the rollback code simple.  So it's best to split r4k_wait into two parts,
one C and one assembler.

Finally add the local_irq_enable() to r4k_wait to ensure the WAIT
instruction in __r4k_wait() will work properly.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

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

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

The generic idle loop has already disabled interrupts so this is redundant.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Without this, the

    WARN_ON_ONCE(irqs_disabled());

in the idle loop will be triggered.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

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

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

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

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

Duplicate and has no business in this header file.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Before f7b861b7 ("arm: Use generic idle loop") ARM would kill the
CPU within the rcu idle section.  Now that the rcu_idle_enter()/exit()
pair have been pushed lower down in the idle loop this is no longer true
and so using RCU_NONIDLE here is no longer necessary and also harmful
because RCU is not actually idle at this point.

Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In commit 78d77df7 ("x86-64, init: Do not set NX bits on non-NX
capable hardware") we added the early_pmd_flags that gets the NX bit set
when a CPU supports NX. However, the new variable was marked __initdata,
because the main _use_ of this is in an __init routine.

However, the bit setting happens from secondary_startup_64(), which is
called not only at bootup, but on every secondary CPU start.  Including
resuming from STR and at CPU hotplug time.  So the value cannot be
__initdata.
Reported-bisected-and-tested-by: NMichal Hocko <mhocko@suse.cz>
Cc: stable@vger.kernel.org # v3.9
Acked-by: NPeter Anvin <hpa@linux.intel.com>
Cc: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit dd72be99.

Andy Shevchenko <andy.shevchenko@gmail.com> reported that this commit
broke Intel Medfield devices.

Reference: https://lkml.kernel.org/r/CAHp75Vdf6gFZChS47=grUygHBDWcoOWDYPzw+Zj5bdVCWj85Jw@mail.gmail.comReported-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

This fixes:

  MODPOST 393 modules
ERROR: "min_low_pfn" [arch/mips/kvm/kvm.ko] undefined!
make[3]: *** [__modpost] Error 1

It would have been possible to just export min_low_pfn but in the end
pfn_valid should return 1 for any pfn argument for which a struct page
exists so using min_low_pfn was wrong anyway.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NJohn Crispin <blogic@openwrt.org>

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NStephen Warren <swarren@nvidia.com>

This sets up the devicetree file for the rt3050 chip series and rt3052
eval board to use the right compatible string for the dwc2 driver.
Acked-by: NJohn Crispin <blogic@openwrt.org>
Cc: blogic@openwrt.org
Cc: linux-mips@linux-mips.org
Cc: Matthijs Kooijman <matthijs@stdin.nl>
Patchwork: https://patchwork.linux-mips.org/patch/5226/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

schedule_mfi is supposed to be extracted from schedule(), and
is used in thread_saved_pc and get_wchan.

But, after optimization, schedule() is reduced to a sibling
call to __schedule(), and no real frame info can be extracted.

One solution is to compile schedule() with -fno-omit-frame-pointer
and -fno-optimize-sibling-calls, but that will incur performance
degradation.

Another solution is to extract info from the real scheduler,
__schedule, and this is the approache adopted here.

This patch reads the __schedule address by either following
the 'j' call in schedule if KALLSYMS is disabled or by using
kallsyms_lookup_name to lookup __schedule if KALLSYMS is
available, then, extracts schedule_mfi from __schedule frame info.

This patch also fixes the "Can't analyze schedule() prologue"
warning at boot time.
Signed-off-by: NTony Wu <tung7970@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5237/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Given a function, get_frame_info() analyzes its instructions
to figure out frame size and return address. get_frame_info()
works as follows:

1. analyze up to 128 instructions if the function size is unknown
2. search for 'addiu/daddiu sp,sp,-immed' for frame size
3. search for 'sw ra,offset(sp)' for return address
4. end search when it sees jr/jal/jalr

This leads to an issue when the given function is a sibling
call, example shown as follows.

801ca110 <schedule>:
801ca110:       8f820000        lw      v0,0(gp)
801ca114:       8c420000        lw      v0,0(v0)
801ca118:       080726f0        j       801c9bc0 <__schedule>
801ca11c:       00000000        nop

801ca120 <io_schedule>:
801ca120:       27bdffe8        addiu   sp,sp,-24
801ca124:       3c028022        lui     v0,0x8022
801ca128:       afbf0014        sw      ra,20(sp)

In this case, get_frame_info() cannot properly detect schedule's
frame info, and eventually returns io_schedule's instead.

This patch adds 'j' to the end search condition to workaround
sibling call cases.
Signed-off-by: NTony Wu <tung7970@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5236/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

EXPORT_SYMBOL and inline directives are contradictory to each other.
The patch fixes this inconsistency.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NDenis Efremov <yefremov.denis@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: trivial@kernel.org
Cc: ldv-project@linuxtesting.org
Patchwork: https://patchwork.linux-mips.org/patch/5227/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

As reported:
  This problem was discovered when doing BGP traffic with the TCP MD5 option
  activated, where the following call chain caused a crash:

   * tcp_v4_rcv
   *  tcp_v4_timewait_ack
   *   tcp_v4_send_ack -> follow stack variable rep.th
   *    tcp_v4_md5_hash_hdr
   *     tcp_md5_hash_header
   *      sg_init_one
   *       sg_set_buf
   *        virt_to_page

  I noticed that tcp_v4_send_reset uses a similar stack variable and
  also calls tcp_v4_md5_hash_hdr, so it has the same problem.

The networking core can indirectly call virt_to_phys() on stack
addresses, if this is done from PID 0, the stack will usually be in
CKSEG0, so virt_to_phys() needs to work there as well
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: Jiang Liu <liuj97@gmail.com>
Cc: eunb.song@samsung.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/5220/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch fixes crash_dump.c build error. Build error logs are as follow.

arch/mips/kernel/crash_dump.c: In function 'kdump_buf_page_init':
arch/mips/kernel/crash_dump.c:67: error: implicit declaration of function 'kmalloc'
arch/mips/kernel/crash_dump.c:67: error: assignment makes pointer from integer without a cast
Signed-off-by: NEunBong Song <eunb.song@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/5238/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>