Userspace can read the exact value of kvmclock by reading the TSC
and fetching the timekeeping parameters out of guest memory.  This
however is brittle and not necessary anymore with KVM 4.11.  Provide
a mechanism that lets userspace know if the new KVM_GET_CLOCK
semantics are in effect, and---since we are at it---if the clock
is stable across all VCPUs.

Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

Function user_notifier_unregister should be called only once for each
registered user notifier.

Function kvm_arch_hardware_disable can be executed from an IPI context
which could cause a race condition with a VCPU returning to user mode
and attempting to unregister the notifier.
Signed-off-by: NIgnacio Alvarado <ikalvarado@google.com>
Cc: stable@vger.kernel.org
Fixes: 18863bdd ("KVM: x86 shared msr infrastructure")
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

Going through the first VCPU is wrong if you follow a KVM_SET_CLOCK with
a KVM_GET_CLOCK immediately after, without letting the VCPU run and
call kvm_guest_time_update.

To fix this, compute the kvmclock value ourselves, using the master
clock (tsc, nsec) pair as the base and the host CPU frequency as
the scale.
Reported-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

KVM calls kvm_pmu_set_counter_event_type() when PMCCFILTR is configured.
But this function can't deals with PMCCFILTR correctly because the evtCount
bits of PMCCFILTR, which is reserved 0, conflits with the SW_INCR event
type of other PMXEVTYPER<n> registers. To fix it, when eventsel == 0, this
function shouldn't return immediately; instead it needs to check further
if select_idx is ARMV8_PMU_CYCLE_IDX.

Another issue is that KVM shouldn't copy the eventsel bits of PMCCFILTER
blindly to attr.config. Instead it ought to convert the request to the
"cpu cycle" event type (i.e. 0x11).

To support this patch and to prevent duplicated definitions, a limited
set of ARMv8 perf event types were relocated from perf_event.c to
asm/perf_event.h.

Cc: stable@vger.kernel.org # 4.6+
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NWei Huang <wei@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

We're missing the handling code for the cycle counter accessed
from a 32bit guest, leading to unexpected results.

Cc: stable@vger.kernel.org # 4.6+
Signed-off-by: NWei Huang <wei@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The rfc4106 encrypy/decrypt helper functions cause an annoying
false-positive warning in allmodconfig if we turn on
-Wmaybe-uninitialized warnings again:

  arch/x86/crypto/aesni-intel_glue.c: In function ‘helper_rfc4106_decrypt’:
  include/linux/scatterlist.h:67:31: warning: ‘dst_sg_walk.sg’ may be used uninitialized in this function [-Wmaybe-uninitialized]

The problem seems to be that the compiler doesn't track the state of the
'one_entry_in_sg' variable across the kernel_fpu_begin/kernel_fpu_end
section.

This takes the easy way out by adding a bogus initialization, which
should be harmless enough to get the patch into v4.9 so we can turn on
this warning again by default without producing useless output.  A
follow-up patch for v4.10 rearranges the code to make the warning go
away.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

gcc correctly warns about an incorrect use of the 'pa' variable in case
we pass an empty scatterlist to __s390_dma_map_sg:

  arch/s390/pci/pci_dma.c: In function '__s390_dma_map_sg':
  arch/s390/pci/pci_dma.c:309:13: warning: 'pa' may be used uninitialized in this function [-Wmaybe-uninitialized]

This adds a bogus initialization to the function to sanitize the debug
output.  I would have preferred a solution without the initialization,
but I only got the report from the kbuild bot after turning on the
warning again, and didn't manage to reproduce it myself.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When called more than twice, the nios2_time_init() function return an
uninitialized value, as detected by gcc -Wmaybe-uninitialized

  arch/nios2/kernel/time.c: warning: 'ret' may be used uninitialized in this function

This makes it return '0' here, matching the comment above the function.
Acked-by: NLey Foon Tan <lftan@altera.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

apm_bios_call() can fail, and return a status in its argument structure.
If that status however is zero during a call from
apm_get_power_status(), we end up using data that may have never been
set, as reported by "gcc -Wmaybe-uninitialized":

  arch/x86/kernel/apm_32.c: In function ‘apm’:
  arch/x86/kernel/apm_32.c:1729:17: error: ‘bx’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  arch/x86/kernel/apm_32.c:1835:5: error: ‘cx’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  arch/x86/kernel/apm_32.c:1730:17: note: ‘cx’ was declared here
  arch/x86/kernel/apm_32.c:1842:27: error: ‘dx’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  arch/x86/kernel/apm_32.c:1731:17: note: ‘dx’ was declared here

This changes the function to return "APM_NO_ERROR" here, which makes the
code more robust to broken BIOS versions, and avoids the warning.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NJiri Kosina <jkosina@suse.cz>
Reviewed-by: NLuis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Traditionally, we have always had warnings about uninitialized variables
enabled, as this is part of -Wall, and generally a good idea [1], but it
also always produced false positives, mainly because this is a variation
of the halting problem and provably impossible to get right in all cases
[2].

Various people have identified cases that are particularly bad for false
positives, and in commit e74fc973 ("Turn off -Wmaybe-uninitialized
when building with -Os"), I turned off the warning for any build that
was done with CC_OPTIMIZE_FOR_SIZE.  This drastically reduced the number
of false positive warnings in the default build but unfortunately had
the side effect of turning the warning off completely in 'allmodconfig'
builds, which in turn led to a lot of warnings (both actual bugs, and
remaining false positives) to go in unnoticed.

With commit 877417e6 ("Kbuild: change CC_OPTIMIZE_FOR_SIZE
definition") enabled the warning again for allmodconfig builds in v4.7
and in v4.8-rc1, I had finally managed to address all warnings I get in
an ARM allmodconfig build and most other maybe-uninitialized warnings
for ARM randconfig builds.

However, commit 6e8d666e ("Disable "maybe-uninitialized" warning
globally") was merged at the same time and disabled it completely for
all configurations, because of false-positive warnings on x86 that I had
not addressed until then.  This caused a lot of actual bugs to get
merged into mainline, and I sent several dozen patches for these during
the v4.9 development cycle.  Most of these are actual bugs, some are for
correct code that is safe because it is only called under external
constraints that make it impossible to run into the case that gcc sees,
and in a few cases gcc is just stupid and finds something that can
obviously never happen.

I have now done a few thousand randconfig builds on x86 and collected
all patches that I needed to address every single warning I got (I can
provide the combined patch for the other warnings if anyone is
interested), so I hope we can get the warning back and let people catch
the actual bugs earlier.

This reverts the change to disable the warning completely and for now
brings it back at the "make W=1" level, so we can get it merged into
mainline without introducing false positives.  A follow-up patch enables
it on all levels unless some configuration option turns it off because
of false-positives.

Link: https://rusty.ozlabs.org/?p=232 [1]
Link: https://gcc.gnu.org/wiki/Better_Uninitialized_Warnings [2]
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Limit the number of kmemleak false positives by including
.data.ro_after_init in memory scanning.  To achieve this we need to add
symbols for start and end of the section to the linker scripts.

The problem was been uncovered by commit 56989f6d ("genetlink: mark
families as __ro_after_init").

Link: http://lkml.kernel.org/r/1478274173-15218-1-git-send-email-jakub.kicinski@netronome.comReviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

pm_rst, aclk_rst and pclk_rst should be controlled by driver, so we
need to add these three resets for PCIe controller.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NHeiko Stuebner <heiko@sntech.de>

ARC linux uses 2 distribution modes for common interrupts: round robin
mode (IDU_M_DISTRI_RR) and a simple destination mode (IDU_M_DISTRI_DEST).
The first one is used when more than 1 cores may handle a common interrupt
and the second one is used when only 1 core may handle a common interrupt.

However idu_irq_set_affinity() always sets IDU_M_DISTRI_RR for all affinity
values. But there is no sense in setting of such mode if only 1 core must
handle a common interrupt.
Signed-off-by: NYuriy Kolerov <yuriy.kolerov@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This came up when reviewing code to address missing IRQ affinity
setting in AXS103 platform and/or implementing hierarchical IRQ domains

- smp_ipi_irq_setup() callers pass hwirq but in turn calls
  request_percpu_irq() which expects a linux virq. So invoke
  irq_find_mapping() to do the conversion
  (also explicitify this in code by renaming the args appropriately)

- idu_of_init()/idu_cascade_isr() were similarly using linux virq where
  hwirq is expected, so do the conversion using irqd_to_hwirq() helper
Signed-off-by: NYuriy Kolerov <yuriy.kolerov@synopsys.com>
[vgupta: made changelog a bit concise a bit]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

For CONFIG_SERIAL_EARLYCON we need 800MHz for NPS SoC
The early console driver uses BASE_BAUD and not using dtb.

The default of 50MHz is NOT good for NPS SoC.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Today we register to plat_smp_ops.clear() method which actually
is acking the IPI.
However this is already taking care by our irqchip driver specifically
by the irq_chip.irq_eoi() method.
This is perfect timing where it should be done and no special handling
is needed at plat_smp_ops.clear().
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This has caused a bunch of build failures at a few sites, with GNU
2015.12 and older as the assembler seems to need -mlock to be able to
grok llock/scond instructions for ARC700 builds.
different places since the
older tools still seem to release
of tools which most people are using seem to trip with the -mlock flag
not being passed.

This reverts commit c3005475.

The current code doesn't even compile as somehow the inline assembly
can't see the register names defined as ARC_RTC_*
I'm pretty sure It worked when I first got it merged, but the tools were
definitely different then.

So better to write this in "C" anyways.

CC: stable@vger.kernel.org	#4.2+
Acked-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

The original syscall only used to return errno to indicate if cmpxchg
succeeded. It was not returning the "previous" value which typical cmpxchg
callers are interested in to build their slowpaths or retry loops.
Given user preemption in syscall return path etc, it is not wise to
check this in userspace afterwards, but should be what kernel actually
observed in the syscall.

So change the syscall interface to always return the previous value and
additionally set Z flag to indicate whether operation succeeded or not
(just like ARM implementation when they used to have this syscall)
The flag approach avoids having to put_user errno which is nice given
the use case for this syscall cares mostly about the "previous" value.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

openrisc qemu tests fail with the following crash.

Unable to handle kernel access at virtual address 0xc0300c34

Oops#: 0001
CPU #: 0
   PC: c016c710    SR: 0000ae67    SP: c1017e04
   GPR00: 00000000 GPR01: c1017e04 GPR02: c0300c34 GPR03: c0300c34
   GPR04: 00000000 GPR05: c0300cb0 GPR06: c0300c34 GPR07: 000000ff
   GPR08: c107f074 GPR09: c0199ef4 GPR10: c1016000 GPR11: 00000000
   GPR12: 00000000 GPR13: c107f044 GPR14: c0473774 GPR15: 07ce0000
   GPR16: 00000000 GPR17: c107ed8a GPR18: 00009600 GPR19: c107f044
   GPR20: c107ee74 GPR21: 00000003 GPR22: c0473770 GPR23: 00000033
   GPR24: 000000bf GPR25: 00000019 GPR26: c046400c GPR27: 00000001
   GPR28: c0464028 GPR29: c1018000 GPR30: 00000006 GPR31: ccf37483
     RES: 00000000 oGPR11: ffffffff
     Process swapper (pid: 1, stackpage=c1001960)

     Stack: Stack dump [0xc1017cf8]:
     sp + 00: 0xc1017e04
     sp + 04: 0xc0300c34
     sp + 08: 0xc0300c34
     sp + 12: 0x00000000
...

Bisect points to commit d2ec3f77 ("pty: make ptmx file ops read-only
after init"). Fix by defining __ro_after_init for the openrisc
architecture, similar to parisc.

Fixes: d2ec3f77 ("pty: make ptmx file ops read-only after init")
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Acked-by: NStafford Horne <shorne@gmail.com>

Commit efd9e03f ("arm64: Use static keys for CPU features")
introduced support for static keys in asm/cpufeature.h, including
linux/jump_label.h. When CC_HAVE_ASM_GOTO is not defined, this causes a
circular dependency via linux/atomic.h, asm/lse.h and asm/cpufeature.h.

This patch moves the capability macros out out of asm/cpufeature.h into
a separate asm/cpucaps.h and modifies some of the #includes accordingly.

Fixes: efd9e03f ("arm64: Use static keys for CPU features")
Reported-by: NArtem Savkov <asavkov@redhat.com>
Tested-by: NArtem Savkov <asavkov@redhat.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Architecturally, TLBs are private to the (physical) CPU they're
associated with. But when multiple vcpus from the same VM are
being multiplexed on the same CPU, the TLBs are not private
to the vcpus (and are actually shared across the VMID).

Let's consider the following scenario:

- vcpu-0 maps PA to VA
- vcpu-1 maps PA' to VA

If run on the same physical CPU, vcpu-1 can hit TLB entries generated
by vcpu-0 accesses, and access the wrong physical page.

The solution to this is to keep a per-VM map of which vcpu ran last
on each given physical CPU, and invalidate local TLBs when switching
to a different vcpu from the same VM.
Reviewed-by: NChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When low memory doesn't reach HIGHMEM_START (e.g. up to 256MB at PA=0 is
common) and highmem is present above HIGHMEM_START (e.g. on Malta the
RAM overlayed by the IO region is aliased at PA=0x90000000), max_low_pfn
will be initially calculated very large and then clipped down to
HIGHMEM_START.

This causes crashes when reading /sys/kernel/mm/page_idle/bitmap
(i.e. CONFIG_IDLE_PAGE_TRACKING=y) when highmem is disabled. pfn_valid()
will compare against max_mapnr which is derived from max_low_pfn when
there is no highend_pfn set up, and will return true for PFNs right up
to HIGHMEM_START, even though they are beyond the end of low memory and
no page structs will actually exist for these PFNs.

This is fixed by skipping high memory regions when initially calculating
max_low_pfn if highmem is disabled, so it doesn't get clipped too high.
We also clip regions which overlap the highmem boundary when highmem is
disabled, so that max_pfn doesn't extend into highmem either.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14490/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Complement commit 80cbfad7 ("MIPS: Correct MIPS I FP context
layout") and correct the way Floating Point General registers are stored
in a signal context with MIPS I hardware.

Use the S.D and L.D assembly macros to have pairs of SWC1 instructions
and pairs of LWC1 instructions produced, respectively, in an arrangement
which makes the memory representation of floating-point data passed
compatible with that used by hardware SDC1 and LDC1 instructions, where
available, regardless of the hardware endianness used.  This matches the
layout used by r4k_fpu.S, ensuring run-time compatibility for MIPS I
software across all o32 hardware platforms.

Define an EX2 macro to handle exceptions from both hardware instructions
implicitly produced from S.D and L.D assembly macros.
Signed-off-by: NMaciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14477/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Fix a regression introduced with commit 2db9ca0a ("MIPS: Use struct
mips_abi offsets to save FP context") for MIPS I/I FP signal contexts,
by converting save/restore code to the updated internal API.  Start FGR
offsets from 0 rather than SC_FPREGS from $a0 and use $a1 rather than
the offset of SC_FPC_CSR from $a0 for the Floating Point Control/Status
Register (FCSR).

Document the new internal API and adjust assembly code formatting for
consistency.
Signed-off-by: NMaciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14476/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Complement commit e50c0a8f ("Support the MIPS32 / MIPS64 DSP ASE.")
and remove the Floating Point Implementation Register (FIR) from the FP
register set recorded in a signal context with MIPS I processors too, in
line with the change applied to r4k_fpu.S.

The `sc_fpc_eir' slot is unused according to our current ABI and the FIR
register is read-only and always directly accessible from user software.

[ralf@linux-mips.org: This is also required because the next commit depends
on it.]
Signed-off-by: NMaciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14475/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Complement commit 0ae8dceaebe3 ("Merge with 2.3.10.") and use the local
`fault' handler to recover from FP sigcontext access violation faults,
like corresponding code does in r4k_fpu.S.  The `bad_stack' handler is
in syscall.c and is not suitable here as we want to propagate the error
condition up through the caller rather than killing the thread outright.
Signed-off-by: NMaciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14474/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Sanitize FCSR Cause bit handling, following a trail of past attempts:

* commit 42495484 ("MIPS: ptrace: Fix FP context restoration FCSR
regression"),

* commit 443c4403 ("MIPS: Always clear FCSR cause bits after
emulation"),

* commit 64bedffe ("MIPS: Clear [MSA]FPE CSR.Cause after
notify_die()"),

* commit b1442d39 ("MIPS: Prevent user from setting FCSR cause
bits"),

* commit b54d2901517d ("Properly handle branch delay slots in connection
with signals.").

Specifically do not mask these bits out in ptrace(2) processing and send
a SIGFPE signal instead whenever a matching pair of an FCSR Cause and
Enable bit is seen as execution of an affected context is about to
resume.  Only then clear Cause bits, and even then do not clear any bits
that are set but masked with the respective Enable bits.  Adjust Cause
bit clearing throughout code likewise, except within the FPU emulator
proper where they are set according to IEEE 754 exceptions raised as the
operation emulated executed.  Do so so that any IEEE 754 exceptions
subject to their default handling are recorded like with operations
executed by FPU hardware.
Signed-off-by: NMaciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14460/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Complement commit ac9ad83b ("MIPS: prevent FP context set via ptrace
being discarded") and also initialize the FP context whenever FCSR alone
is written with a PTRACE_POKEUSR request addressing FPC_CSR, rather than
along with the full FPU register set in the case of the PTRACE_SETFPREGS
request.
Signed-off-by: NMaciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14459/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since commit 4bcc595c ("printk: reinstate KERN_CONT for printing
continuation lines") the output from TLB dumps on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output.

Continuation is also used for the second line of each TLB entry printed
in dump_tlb.c even though it has a newline, since it is a continuation
of the interpretation of the same TLB entry. For example:

[   46.371884] Index:  0 pgmask=16kb va=77654000 asid=73 gid=00
        [ri=0 xi=0 pa=ffc18000 c=5 d=0 v=1 g=0] [ri=0 xi=0 pa=ffc1c000 c=5 d=0 v=1 g=0]
[   46.385380] Index: 12 pgmask=16kb va=004b4000 asid=73 gid=00
        [ri=0 xi=0 pa=00000000 c=0 d=0 v=0 g=0] [ri=0 xi=0 pa=ffb00000 c=5 d=1 v=1 g=0]
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14444/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since commit 4bcc595c ("printk: reinstate KERN_CONT for printing
continuation lines") the output from __show_regs() on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected register output.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14432/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since commit 4bcc595c ("printk: reinstate KERN_CONT for printing
continuation lines") the output from show_code on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14431/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since commit 4bcc595c ("printk: reinstate KERN_CONT for printing
continuation lines") the output from show_stacktrace on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output. Also
start a new line with printk such that the presence of timing
information does not interfere with output.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14430/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since commit 4bcc595c ("printk: reinstate KERN_CONT for printing
continuation lines") the output from show_backtrace on MIPS has been
pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont to
provide the appropriate markers & restore the expected output.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14429/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Changes introduced to arch/mips/Makefile for the generic kernel resulted
in build errors when making a compressed image if platform-y has multiple
values, like this:

make[2]: *** No rule to make target `alchemy/'.
make[1]: *** [vmlinuz] Error 2
make[1]: Target `_all' not remade because of errors.
make: *** [sub-make] Error 2
make: Target `_all' not remade because of errors.

Fix this by quoting $(platform-y) as it is passed to the Makefile in
arch/mips/boot/compressed/Makefile
Reported-by: Nkernelci.org bot <bot@kernelci.org>
Link: https://storage.kernelci.org/next/next-20161017/mips-gpr_defconfig/build.logSigned-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14405/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The KASLR code requires that the plat_get_fdt() function return the
address of the device tree, and it must be available early in the boot,
before prom_init() is called. Move the code determining the address of
the device tree into plat_get_fdt, and call that from prom_init().

The fdt pointer will be set up by plat_get_fdt() called from
relocate_kernel initially and once the relocated kernel has started,
prom_init() will use it again to determine the address in the relocated
image.

Fixes: eed0eabd ("MIPS: generic: Introduce generic DT-based board support")
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>
Reviewed-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14415/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14414/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit 10b6ea09 ("MIPS: Malta: Use syscon-reboot driver to reboot")
converted the Malta board to use the generic syscon-reboot driver to
handle reboots, but incorrectly used the value 0x4d rather than 0x42 as
the magic to write to the reboot register.

I also incorrectly believed that syscon/regmap would default to native
endianness, but this isn't the case. Force this by specifying with a
native-endian property in the devicetree.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Fixes: 10b6ea09 ("MIPS: Malta: Use syscon-reboot driver to reboot")
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Cc: linux-mips@linux-mips.org
Tested-by: NGuenter Roeck <linux@roeck-us.net>
Tested-by: NMaciej W. Rozycki <macro@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/14396/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Provide a default implementation of mips_cpc_default_phys_base() which
simply returns 0, and adjust mips_cpc_phys_base() to allow for
mips_cpc_default_phys_base() returning 0. This allows kernels which
include CPC support to be built without platform code & simply ignore
the CPC if it wasn't already enabled by the bootloader.

This fixes link failures such as the following from generic defconfigs:

   arch/mips/built-in.o: In function `mips_cpc_phys_base':
   arch/mips/kernel/mips-cpc.c:47: undefined reference to `mips_cpc_default_phys_base'

[ralf@linux-mips.org: changed prototype for coding style compliance.]
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14401/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We used to use generic implementation of dma_map_ops.mmap which is
dma_common_mmap() but that only worked for simpler cached mappings when
vaddr = paddr.

If a driver requests uncached DMA buffer kernel maps it to virtual
address so that MMU gets involved and page uncached status takes into
account. In that case usage of dma_common_mmap() lead to mapping of
vaddr to vaddr for user-space which is obviously wrong. For more detals
please refer to verbose explanation here [1].

So here we implement our own version of mmap() which always deals
with dma_addr and maps underlying memory to user-space properly
(note that DMA buffer mapped to user-space is always uncached
because there's no way to properly manage cache from user-space).

[1] https://lkml.org/lkml/2016/10/26/973Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: <stable@vger.kernel.org>  #4.5+
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>