linux-stable.git/arch/mips/include/asm, branch v4.19.78

MIPS: Ingenic: Disable broken BTB lookup optimization.

2019-10-07T16:57:06+00:00

[ Upstream commit 053951dda71ecb4b554a2cdbe26f5f6f9bee9dd2 ]

In order to further reduce power consumption, the XBurst core
by default attempts to avoid branch target buffer lookups by
detecting & special casing loops. This feature will cause
BogoMIPS and lpj calculate in error. Set cp0 config7 bit 4 to
disable this feature.

Signed-off-by: Zhou Yanjie 
Signed-off-by: Paul Burton 
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: ralf@linux-mips.org
Cc: paul@crapouillou.net
Cc: jhogan@kernel.org
Cc: malat@debian.org
Cc: gregkh@linuxfoundation.org
Cc: tglx@linutronix.de
Cc: allison@lohutok.net
Cc: syq@debian.org
Cc: chenhc@lemote.com
Cc: jiaxun.yang@flygoat.com
Signed-off-by: Sasha Levin

MIPS: ath79: fix ar933x uart parity mode

2019-07-26T07:13:55+00:00

[ Upstream commit db13a5ba2732755cf13320f3987b77cf2a71e790 ]

While trying to get the uart with parity working I found setting even
parity enabled odd parity insted. Fix the register settings to match
the datasheet of AR9331.

A similar patch was created by 8devices, but not sent upstream.
https://github.com/8devices/openwrt-8devices/commit/77c5586ade3bb72cda010afad3f209ed0c98ea7c

Signed-off-by: Stefan Hellermann 
Signed-off-by: Paul Burton 
Cc: linux-mips@vger.kernel.org
Signed-off-by: Sasha Levin

irqchip/mips-gic: Use the correct local interrupt map registers

2019-07-03T11:14:46+00:00

commit 6d4d367d0e9ffab4d64a3436256a6a052dc1195d upstream.

The MIPS GIC contains a block of registers used to map local interrupts
to a particular CPU interrupt pin. Since these registers are found at a
consecutive range of addresses we access them using an index, via the
(read|write)_gic_v[lo]_map accessor functions. We currently use values
from enum mips_gic_local_interrupt as those indices.

Unfortunately whilst enum mips_gic_local_interrupt provides the correct
offsets for bits in the pending & mask registers, the ordering of the
map registers is subtly different... Compared with the ordering of
pending & mask bits, the map registers move the FDC from the end of the
list to index 3 after the timer interrupt. As a result the performance
counter & software interrupts are therefore at indices 4-6 rather than
indices 3-5.

Notably this causes problems with performance counter interrupts being
incorrectly mapped on some systems, and presumably will also cause
problems for FDC interrupts.

Introduce a function to map from enum mips_gic_local_interrupt to the
index of the corresponding map register, and use it to ensure we access
the map registers for the correct interrupts.

Signed-off-by: Paul Burton 
Fixes: a0dc5cb5e31b ("irqchip: mips-gic: Simplify gic_local_irq_domain_map()")
Fixes: da61fcf9d62a ("irqchip: mips-gic: Use irq_cpu_online to (un)mask all-VP(E) IRQs")
Reported-and-tested-by: Archer Yan 
Cc: Thomas Gleixner 
Cc: Jason Cooper 
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Marc Zyngier 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix kernel crash for R6 in jump label branch function

2019-03-27T05:14:39+00:00

commit 47c25036b60f27b86ab44b66a8861bcf81cde39b upstream.

Insert Branch instruction instead of NOP to make sure assembler don't
patch code in forbidden slot. In jump label function, it might
be possible to patch Control Transfer Instructions(CTIs) into
forbidden slot, which will generate Reserved Instruction exception
in MIPS release 6.

Signed-off-by: Archer Yan 
Reviewed-by: Paul Burton 
[paul.burton@mips.com:
  - Add MIPS prefix to subject.
  - Mark for stable from v4.0, which introduced r6 support, onwards.]
Signed-off-by: Paul Burton 
Cc: linux-mips@vger.kernel.org
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Greg Kroah-Hartman

KVM: Call kvm_arch_memslots_updated() before updating memslots

2019-03-23T19:10:13+00:00

commit 152482580a1b0accb60676063a1ac57b2d12daf6 upstream.

kvm_arch_memslots_updated() is at this point in time an x86-specific
hook for handling MMIO generation wraparound.  x86 stashes 19 bits of
the memslots generation number in its MMIO sptes in order to avoid
full page fault walks for repeat faults on emulated MMIO addresses.
Because only 19 bits are used, wrapping the MMIO generation number is
possible, if unlikely.  kvm_arch_memslots_updated() alerts x86 that
the generation has changed so that it can invalidate all MMIO sptes in
case the effective MMIO generation has wrapped so as to avoid using a
stale spte, e.g. a (very) old spte that was created with generation==0.

Given that the purpose of kvm_arch_memslots_updated() is to prevent
consuming stale entries, it needs to be called before the new generation
is propagated to memslots.  Invalidating the MMIO sptes after updating
memslots means that there is a window where a vCPU could dereference
the new memslots generation, e.g. 0, and incorrectly reuse an old MMIO
spte that was created with (pre-wrap) generation==0.

Fixes: e59dbe09f8e6 ("KVM: Introduce kvm_arch_memslots_updated()")
Cc: 
Signed-off-by: Sean Christopherson 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

mmc: jz4740: Get CD/WP GPIOs from descriptors

2019-02-12T18:47:10+00:00

[ Upstream commit 0c901c0566fb4edc2631c3786e5085a037be91f8 ]

Modifty the JZ4740 driver to retrieve card detect and write
protect GPIO pins from GPIO descriptors instead of hard-coded
global numbers. Augment the only board file using this in the
process and cut down on passed in platform data.

Preserve the code setting the caps2 flags for CD and WP
as active low or high since the slot GPIO code currently
ignores the gpiolib polarity inversion semantice and uses
the raw accessors to read the GPIO lines, but set the right
polarity flags in the descriptor table for jz4740.

Cc: Paul Cercueil 
Cc: linux-mips@linux-mips.org
Signed-off-by: Linus Walleij 
Acked-by: Paul Burton 
Signed-off-by: Ulf Hansson 
Signed-off-by: Sasha Levin

MIPS: Only include mmzone.h when CONFIG_NEED_MULTIPLE_NODES=y

2019-01-09T16:38:49+00:00

commit 66a4059ba72c23ae74a7c702894ff76c4b7eac1f upstream.

MIPS' asm/mmzone.h includes the machine/platform mmzone.h
unconditionally, but since commit bb53fdf395ee ("MIPS: c-r4k: Add
r4k_blast_scache_node for Loongson-3") is included by asm/rk4cache.h for
all r4k-style configs regardless of CONFIG_NEED_MULTIPLE_NODES.

This is problematic when CONFIG_NEED_MULTIPLE_NODES=n because both the
loongson3 & ip27 mmzone.h headers unconditionally define the NODE_DATA
preprocessor macro which is aready defined by linux/mmzone.h, resulting
in the following build error:

  In file included from ./arch/mips/include/asm/mmzone.h:10,
                   from ./arch/mips/include/asm/r4kcache.h:23,
                   from arch/mips/mm/c-r4k.c:33:
  ./arch/mips/include/asm/mach-loongson64/mmzone.h:48: error: "NODE_DATA" redefined [-Werror]
   #define NODE_DATA(n)  (&__node_data[(n)]->pglist)

  In file included from ./include/linux/topology.h:32,
                   from ./include/linux/irq.h:19,
                   from ./include/asm-generic/hardirq.h:13,
                   from ./arch/mips/include/asm/hardirq.h:16,
                   from ./include/linux/hardirq.h:9,
                   from arch/mips/mm/c-r4k.c:11:
  ./include/linux/mmzone.h:907: note: this is the location of the previous definition
   #define NODE_DATA(nid)  (&contig_page_data)

Resolve this by only including the machine mmzone.h when
CONFIG_NEED_MULTIPLE_NODES=y, which also removes the need for the empty
mach-generic version of the header which we delete.

Signed-off-by: Paul Burton 
Fixes: bb53fdf395ee ("MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3")
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix a R10000_LLSC_WAR logic in atomic.h

2019-01-09T16:38:48+00:00

commit db1ce3f5d01d2d6d5714aefba0159d2cb5167a0b upstream.

Commit 4936084c2ee2 ("MIPS: Cleanup R10000_LLSC_WAR logic in atomic.h")
introduce a mistake in atomic64_fetch_##op##_relaxed(), because it
forget to delete R10000_LLSC_WAR in the if-condition. So fix it.

Fixes: 4936084c2ee2 ("MIPS: Cleanup R10000_LLSC_WAR logic in atomic.h")
Signed-off-by: Huacai Chen 
Signed-off-by: Paul Burton 
Cc: Joshua Kinard 
Cc: Ralf Baechle 
Cc: Steven J . Hill 
Cc: Fuxin Zhang 
Cc: Zhangjin Wu 
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Greg Kroah-Hartman

MIPS: Expand MIPS32 ASIDs to 64 bits

2019-01-09T16:38:48+00:00

commit ff4dd232ec45a0e45ea69f28f069f2ab22b4908a upstream.

ASIDs have always been stored as unsigned longs, ie. 32 bits on MIPS32
kernels. This is problematic because it is feasible for the ASID version
to overflow & wrap around to zero.

We currently attempt to handle this overflow by simply setting the ASID
version to 1, using asid_first_version(), but we make no attempt to
account for the fact that there may be mm_structs with stale ASIDs that
have versions which we now reuse due to the overflow & wrap around.

Encountering this requires that:

  1) A struct mm_struct X is active on CPU A using ASID (V,n).

  2) That mm is not used on CPU A for the length of time that it takes
     for CPU A's asid_cache to overflow & wrap around to the same
     version V that the mm had in step 1. During this time tasks using
     the mm could either be sleeping or only scheduled on other CPUs.

  3) Some other mm Y becomes active on CPU A and is allocated the same
     ASID (V,n).

  4) mm X now becomes active on CPU A again, and now incorrectly has the
     same ASID as mm Y.

Where struct mm_struct ASIDs are represented above in the format
(version, EntryHi.ASID), and on a typical MIPS32 system version will be
24 bits wide & EntryHi.ASID will be 8 bits wide.

The length of time required in step 2 is highly dependent upon the CPU &
workload, but for a hypothetical 2GHz CPU running a workload which
generates a new ASID every 10000 cycles this period is around 248 days.
Due to this long period of time & the fact that tasks need to be
scheduled in just the right (or wrong, depending upon your inclination)
way, this is obviously a difficult bug to encounter but it's entirely
possible as evidenced by reports.

In order to fix this, simply extend ASIDs to 64 bits even on MIPS32
builds. This will extend the period of time required for the
hypothetical system above to encounter the problem from 28 days to
around 3 trillion years, which feels safely outside of the realms of
possibility.

The cost of this is slightly more generated code in some commonly
executed paths, but this is pretty minimal:

                         | Code Size Gain | Percentage
  -----------------------|----------------|-------------
    decstation_defconfig |           +270 | +0.00%
        32r2el_defconfig |           +652 | +0.01%
        32r6el_defconfig |          +1000 | +0.01%

I have been unable to measure any change in performance of the LMbench
lat_ctx or lat_proc tests resulting from the 64b ASIDs on either
32r2el_defconfig+interAptiv or 32r6el_defconfig+I6500 systems.

Signed-off-by: Paul Burton 
Suggested-by: James Hogan 
References: https://lore.kernel.org/linux-mips/80B78A8B8FEE6145A87579E8435D78C30205D5F3@fzex.ruijie.com.cn/
References: https://lore.kernel.org/linux-mips/1488684260-18867-1-git-send-email-jiwei.sun@windriver.com/
Cc: Jiwei Sun 
Cc: Yu Huabing 
Cc: stable@vger.kernel.org # 2.6.12+
Cc: linux-mips@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

MIPS: Ensure pmd_present() returns false after pmd_mknotpresent()

2019-01-09T16:38:47+00:00

commit 92aa0718c9fa5160ad2f0e7b5bffb52f1ea1e51a upstream.

This patch is borrowed from ARM64 to ensure pmd_present() returns false
after pmd_mknotpresent(). This is needed for THP.

References: 5bb1cc0ff9a6 ("arm64: Ensure pmd_present() returns false after pmd_mknotpresent()")
Reviewed-by: James Hogan 
Signed-off-by: Huacai Chen 
Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/21135/
Cc: Ralf Baechle 
Cc: James Hogan 
Cc: Steven J . Hill 
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang 
Cc: Zhangjin Wu 
Cc:  # 3.8+
Signed-off-by: Greg Kroah-Hartman