In current scache init cache line_size is determined from
cpu config register, however if there there no scache
then mips_sc_probe_cm3 function populates a invalid line_size of 2.
The invalid line_size can cause a NULL pointer deference
during r4k_dma_cache_inv as r4k_blast_scache is populated
based on line_size. Scache line_size of 2 is invalid option in
r4k_blast_scache_setup.
This issue was faced during a MIPS I6400 based virtual platform bring up
where scache was not available in virtual platform model.
Signed-off-by: Govindraj Raja <Govindraj.Raja@imgtec.com>
Fixes: 7d53e9c4cd21("MIPS: CM3: Add support for CM3 L2 cache.")
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hartley <James.Hartley@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v4.2+
Patchwork: https://patchwork.linux-mips.org/patch/12710/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The target independent parts of the LLVM Lexer considers 'fault@function'
to be a single token representing the 'fault' symbol with a 'function'
modifier. However, this is not the case in the .type directive where
'function' refers to STT_FUNC from the ELF standard.
Although GAS accepts it, '.type symbol@function' is an undocumented form of
this directive. The documentation specifies a comma between the symbol and
'@function'.
Signed-off-by: Scott Egerton <Scott.Egerton@imgtec.com>
Signed-off-by: Daniel Sanders <daniel.sanders@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12587/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is fallout from commit 832f5dacfa ("MIPS: Remove all the uses of
custom gpio.h").
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Suggested-by: Lars-Peter Clausen <lars@metafoo.de>
This patch add the SO_CNX_ADVICE socket option (setsockopt only). The
purpose is to allow an application to give feedback to the kernel about
the quality of the network path for a connected socket. The value
argument indicates the type of quality report. For this initial patch
the only supported advice is a value of 1 which indicates "bad path,
please reroute"-- the action taken by the kernel is to call
dst_negative_advice which will attempt to choose a different ECMP route,
reset the TX hash for flow label and UDP source port in encapsulation,
etc.
This facility should be useful for connected UDP sockets where only the
application can provide any feedback about path quality. It could also
be useful for TCP applications that have additional knowledge about the
path outside of the normal TCP control loop.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This config was used for the ARM port so that it could use a
machine specific clkdev.h include, but those are all gone now.
The MIPS architecture is the last user, and from what I can tell
it doesn't actually use it anyway, so let's remove the config all
together.
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: <linux-mips@linux-mips.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Joshua Henderson <joshua.henderson@microchip.com>
The problem:
On -rt, an emulated LAPIC timer instances has the following path:
1) hard interrupt
2) ksoftirqd is scheduled
3) ksoftirqd wakes up vcpu thread
4) vcpu thread is scheduled
This extra context switch introduces unnecessary latency in the
LAPIC path for a KVM guest.
The solution:
Allow waking up vcpu thread from hardirq context,
thus avoiding the need for ksoftirqd to be scheduled.
Normal waitqueues make use of spinlocks, which on -RT
are sleepable locks. Therefore, waking up a waitqueue
waiter involves locking a sleeping lock, which
is not allowed from hard interrupt context.
cyclictest command line:
This patch reduces the average latency in my tests from 14us to 11us.
Daniel writes:
Paolo asked for numbers from kvm-unit-tests/tscdeadline_latency
benchmark on mainline. The test was run 1000 times on
tip/sched/core 4.4.0-rc8-01134-g0905f04:
./x86-run x86/tscdeadline_latency.flat -cpu host
with idle=poll.
The test seems not to deliver really stable numbers though most of
them are smaller. Paolo write:
"Anything above ~10000 cycles means that the host went to C1 or
lower---the number means more or less nothing in that case.
The mean shows an improvement indeed."
Before:
min max mean std
count 1000.000000 1000.000000 1000.000000 1000.000000
mean 5162.596000 2019270.084000 5824.491541 20681.645558
std 75.431231 622607.723969 89.575700 6492.272062
min 4466.000000 23928.000000 5537.926500 585.864966
25% 5163.000000 1613252.750000 5790.132275 16683.745433
50% 5175.000000 2281919.000000 5834.654000 23151.990026
75% 5190.000000 2382865.750000 5861.412950 24148.206168
max 5228.000000 4175158.000000 6254.827300 46481.048691
After
min max mean std
count 1000.000000 1000.00000 1000.000000 1000.000000
mean 5143.511000 2076886.10300 5813.312474 21207.357565
std 77.668322 610413.09583 86.541500 6331.915127
min 4427.000000 25103.00000 5529.756600 559.187707
25% 5148.000000 1691272.75000 5784.889825 17473.518244
50% 5160.000000 2308328.50000 5832.025000 23464.837068
75% 5172.000000 2393037.75000 5853.177675 24223.969976
max 5222.000000 3922458.00000 6186.720500 42520.379830
[Patch was originaly based on the swait implementation found in the -rt
tree. Daniel ported it to mainline's version and gathered the
benchmark numbers for tscdeadline_latency test.]
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-rt-users@vger.kernel.org
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1455871601-27484-4-git-send-email-wagi@monom.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull the second round of irqchip core changes for v4.6 from Jason Cooper:
- mvebu:
- Add odmi driver for Marvell 7K/8K SoCs
- Replace driver-specific set_affinity with generic version
- mips:
- Move ath79 MISC and CPU drivers from arch/ code to irqchip/
- tango:
- Add support for Sigma Designs SMP8[67]xx ctrl
This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().
Cc: linux-mips@linux-mips.org
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().
Cc: linux-mips@linux-mips.org
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().
Cc: linux-mips@linux-mips.org
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This is fallout from commit 832f5dacfa ("MIPS: Remove all the uses of
custom gpio.h").
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Suggested-by: Lars-Peter Clausen <lars@metafoo.de>
The driver stays the same but the initialization changes a bit.
For OF boards we now get the memory map from the OF node and use
a linear mapping instead of the legacy mapping. For legacy boards
we still use a legacy mapping and just pass down all the parameters
from the board init code.
Signed-off-by: Alban Bedel <albeu@free.fr>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1453553867-27003-1-git-send-email-albeu@free.fr
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Pull MIPS fixes from Ralf Baechle:
"Here's the first round of MIPS fixes after the merge window:
- Detect Octeon III's PCI correctly.
- Fix return value of the MT7620 probing function.
- Wire up the copy_file_range syscall.
- Fix 64k page support on 32 bit kernels.
- Fix the early Coherency Manager probe.
- Allow only hardware-supported page sizes to be selected for R6000.
- Fix corner cases for the RDHWR nstruction emulation on old hardware.
- Fix FPU handling corner cases.
- Remove stale entry for BCM33xx from the MAINTAINERS file.
- 32 and 64 bit ELF headers are different, handle them correctly"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
mips: Differentiate between 32 and 64 bit ELF header
MIPS: Octeon: Update OCTEON_FEATURE_PCIE for Octeon III
MIPS: pci-mt7620: Fix return value check in mt7620_pci_probe()
MIPS: Fix early CM probing
MIPS: Wire up copy_file_range syscall.
MIPS: Fix 64k page support for 32 bit kernels.
MIPS: R6000: Don't allow 64k pages for R6000.
MIPS: traps.c: Correct microMIPS RDHWR emulation
MIPS: traps.c: Don't emulate RDHWR in the CpU #0 exception handler
MAINTAINERS: Remove stale entry for BCM33xx chips
MIPS: Fix FPU disable with preemption
MIPS: Properly disable FPU in start_thread()
MIPS: Fix buffer overflow in syscall_get_arguments()
Depending on the configuration either the 32 or 64 bit version of
elf_check_arch() is defined. parse_crash_elf{32|64}_headers() does
some basic verification of the ELF header via
vmcore_elf{32|64}_check_arch() which happen to map to elf_check_arch().
Since the implementation 32 and 64 bit version of elf_check_arch()
differ, we use the wrong type:
In file included from include/linux/elf.h:4:0,
from fs/proc/vmcore.c:13:
fs/proc/vmcore.c: In function 'parse_crash_elf64_headers':
>> arch/mips/include/asm/elf.h:228:23: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
struct elfhdr *__h = (hdr); \
^
include/linux/crash_dump.h:41:37: note: in expansion of macro 'elf_check_arch'
#define vmcore_elf64_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x))
^
fs/proc/vmcore.c:1015:4: note: in expansion of macro 'vmcore_elf64_check_arch'
!vmcore_elf64_check_arch(&ehdr) ||
^
Therefore, we rather define vmcore_elf{32|64}_check_arch() as a
basic machine check and use it also in binfm_elf?32.c as well.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Suggested-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12529/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CONFIG_KEYS_DEBUG_PROC_KEYS is no longer an option as /proc/keys is now
mandatory if the keyrings facility is enabled (it's used by libkeyutils in
userspace).
The defconfig references were removed with:
perl -p -i -e 's/CONFIG_KEYS_DEBUG_PROC_KEYS=y\n//' \
`git grep -l CONFIG_KEYS_DEBUG_PROC_KEYS=y`
and the integrity Kconfig fixed by hand.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Andreas Ziegler <andreas.ziegler@fau.de>
cc: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Pull regmap fix from Mark Brown:
"A single revert back to v4.4 endianness handling.
Commit 29bb45f25f ("regmap-mmio: Use native endianness for
read/write") attempted to fix some long standing bugs in the MMIO
implementation for big endian systems caused by duplicate byte
swapping in both regmap and readl()/writel(). Sadly the fix makes
things worse rather than better, so revert it for now"
* tag 'regmap-fix-v4.5-big-endian' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: mmio: Revert to v4.4 endianness handling
include/asm-generic/pci-bridge.h is now empty, so remove every #include of
it.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Will Deacon <will.deacon@arm.com> (arm64)
Commit 29bb45f25f (regmap-mmio: Use native endianness for read/write)
attempted to fix some long standing bugs in the MMIO implementation for
big endian systems caused by duplicate byte swapping in both regmap and
readl()/writel() which affected MIPS systems as when they are in big
endian mode they flip the endianness of all registers in the system, not
just the CPU. MIPS systems had worked around this by declaring regmap
using IPs as little endian which is inaccurate, unfortunately the issue
had not been reported.
Sadly the fix makes things worse rather than better. By changing the
behaviour to match the documentation it caused behaviour changes for
other IPs which broke them and by using the __raw I/O accessors to avoid
the endianness swapping in readl()/writel() it removed some memory
ordering guarantees and could potentially generate unvirtualisable
instructions on some architectures.
Unfortunately sorting out all this mess in any half way sensible fashion
was far too invasive to go in during an -rc cycle so instead let's go
back to the old broken behaviour for v4.5, the better fixes are already
queued for v4.6. This does mean that we keep the broken MIPS DTs for
another release but that seems the least bad way of handling the
situation.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
TASK_SIZE was defined as 0x7fff8000UL which for 64k pages is not a
multiple of the page size. Somewhere further down the math fails
such that executing an ELF binary fails.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Tested-by: Joshua Henderson <joshua.henderson@microchip.com>
In the regular MIPS instruction set RDHWR is encoded with the SPECIAL3
(011111) major opcode. Therefore it cannot trigger the CpU (Coprocessor
Unusable) exception, and certainly not for coprocessor 0, as the opcode
does not overlap with any of the older ISA reservations, i.e. LWC0
(110000), SWC0 (111000), LDC0 (110100) or SDC0 (111100). The closest
match might be SDC3 (111111), possibly causing a CpU #3 exception,
however our code does not handle it anyway. A quick check with a MIPS I
and a MIPS III processor:
CPU0 revision is: 00000220 (R3000)
CPU0 revision is: 00000440 (R4400SC)
indeed indicates that the RI (Reserved Instruction) exception is
triggered. It's only LL and SC that require emulation in the CpU #0
exception handler as they reuse the LWC0 and SWC0 opcodes respectively.
In the microMIPS instruction set RDHWR is mandatory and triggering the
RI exception is required on unimplemented or disabled register accesses.
Therefore emulating the microMIPS instruction in the CpU #0 exception
handler is not required either.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12280/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The FPU should not be left enabled after a task context switch. This
isn't usually a problem as the FPU enable bit is updated before
returning to userland, however it can potentially mask kernel bugs, and
in fact KVM assumes it won't happen and won't clear the FPU enable bit
before returning to the guest, which allows the guest to use stale FPU
context.
Interrupts and exceptions save and restore most bits of the CP0 Status
register which contains the FPU enable bit (CU1). When the kernel needs
to enable or disable the FPU (for example due to attempted FPU use by
userland, or the scheduler being invoked) both the actual Status
register and the saved value in the userland context are updated.
However this doesn't work correctly with full kernel preemption enabled,
since the FPU enable bit can be cleared from within an interrupt when
the scheduler is invoked, and only the userland context is updated, not
the interrupt context.
For example:
1) Enter kernel with FPU already enabled, TIF_USEDFPU=1, Status.CU1=1
saved.
2) Take a timer interrupt while in kernel mode, Status.CU1=1 saved.
3) Timer interrupt invokes scheduler to preempt the task, which clears
TIF_USEDFPU, disables the FPU in Status register (Status.CU1=0), and
the value stored in user context from step (1), but not the interrupt
context from step (2).
4) When the process is scheduled back in again Status.CU1=0.
5) The interrupt context from step (2) is restored, which sets
Status.CU1=1. So from user context point of view, preemption has
re-enabled FPU!
6) If the scheduler is invoked again (via preemption or voluntarily)
before returning to userland, TIF_USEDFPU=0 so the FPU is not
disabled before the task context switch.
7) The next task resumes from the context switch with FPU enabled!
The restoring of the Status register on return from interrupt/exception
is already selective about which bits to restore, leaving the interrupt
mask bits alone so enabling/disabling of CPU interrupt lines can
persist. Extend this to also leave both the CU1 bit (FPU enable) and the
FR bit (which specifies the FPU mode and gets changed with CU1). This
prevents a stale Status value being restored in step (5) above and
persisting through subsequent context switches.
Also switch to the use of definitions from asm/mipsregs.h while we're at
it.
Since this change also affects the restoration of Status register on the
path back to userland, it increases the sensitivity of the kernel to the
problem of the FPU being left enabled, allowing it to propagate to
userland, therefore a warning is also added to lose_fpu_inatomic() to
point out any future reoccurances before they do any damage.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12303/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
start_thread() (called for execve(2)) clears the TIF_USEDFPU flag
without atomically disabling the FPU. With a preemptive kernel, an
unfortunately timed preemption after this could result in another
task (or KVM guest) being scheduled in with the FPU still enabled, since
lose_fpu_inatomic() only turns it off if TIF_USEDFPU is set.
Use lose_fpu(0) instead of the separate FPU / MSA management, which
should do the right thing (drop FPU properly and atomically without
saving state) and will be more future proof.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12302/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 4c21b8fd8f ("MIPS: seccomp: Handle indirect system calls
(o32)"), syscall_get_arguments() attempts to handle o32 indirect syscall
arguments by incrementing both the start argument number and the number
of arguments to fetch. However only the start argument number needs to
be incremented. The number of arguments does not change, they're just
shifted up by one, and in fact the output array is provided by the
caller and is likely only n entries long, so reading more arguments
overflows the output buffer.
In the case of seccomp, this results in it fetching 7 arguments starting
at the 2nd one, which overflows the unsigned long args[6] in
populate_seccomp_data(). This clobbers the $s0 register from
syscall_trace_enter() which __seccomp_phase1_filter() saved onto the
stack, into which syscall_trace_enter() had placed its syscall number
argument. This caused Chromium to crash.
Credit goes to Milko for tracking it down as far as $s0 being clobbered.
Fixes: 4c21b8fd8f ("MIPS: seccomp: Handle indirect system calls (o32)")
Reported-by: Milko Leporis <milko.leporis@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15-
Patchwork: https://patchwork.linux-mips.org/patch/12213/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
