cmd_dt_S_dtb constructs the assembly source to incorporate a devicetree
FDT (that is, the .dtb file) as binary data in the kernel image. This
assembly source contains labels before and after the binary data. The
label names incorporate the file name of the corresponding .dtb file.
Hyphens are not legal characters in labels, so .dtb files built into the
kernel with hyphens in the file name result in errors like the
following:
bcm3368-netgear-cvg834g.dtb.S: Assembler messages:
bcm3368-netgear-cvg834g.dtb.S:5: Error: : no such section
bcm3368-netgear-cvg834g.dtb.S:5: Error: junk at end of line, first unrecognized character is `-'
bcm3368-netgear-cvg834g.dtb.S:6: Error: unrecognized opcode `__dtb_bcm3368-netgear-cvg834g_begin:'
bcm3368-netgear-cvg834g.dtb.S:8: Error: unrecognized opcode `__dtb_bcm3368-netgear-cvg834g_end:'
bcm3368-netgear-cvg834g.dtb.S:9: Error: : no such section
bcm3368-netgear-cvg834g.dtb.S:9: Error: junk at end of line, first unrecognized character is `-'
Fix this by updating cmd_dt_S_dtb to transform all hyphens from the file
name to underscores when constructing the labels.
As of v4.16-rc2, 1139 .dts files across ARM64, ARM, MIPS and PowerPC
contain hyphens in their names, but the issue only currently manifests
on Broadcom MIPS platforms, as that is the only place where such files
are built into the kernel. For example when CONFIG_DT_NETGEAR_CVG834G=y,
or on BMIPS kernels when the dtbs target is used (in the latter case it
admittedly shouldn't really build all the dtb.o files, but thats a
separate issue).
Fixes: 695835511f ("MIPS: BMIPS: rename bcm96358nb4ser to bcm6358-neufbox4-sercom")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Frank Rowand <frowand.list@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: <stable@vger.kernel.org> # 4.9+
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The core Meta architecture support has now been removed, so drop the
MAINTAINERS entry and add an entry to CREDITS.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: linux-metag@vger.kernel.org
Expand the MIPS Makefile help text to list generic board names, generic
defconfigs, and legacy defconfigs which have been converted to generic
and are still usable.
Here's a snippet of the new "make ARCH=mips help" output:
...
If you are targeting a system supported by generic kernels you may
configure the kernel for a given architecture target like so:
{micro32,32,64}{r1,r2,r6}{el,}_defconfig <BOARDS="list of boards">
Where BOARDS is some subset of the following:
boston
ni169445
ranchu
sead-3
xilfpga
Specifically the following generic default configurations are
supported:
32r1_defconfig - Build generic kernel for MIPS32 r1
32r1el_defconfig - Build generic kernel for MIPS32 r1 little endian
32r2_defconfig - Build generic kernel for MIPS32 r2
32r2el_defconfig - Build generic kernel for MIPS32 r2 little endian
32r6_defconfig - Build generic kernel for MIPS32 r6
32r6el_defconfig - Build generic kernel for MIPS32 r6 little endian
64r1_defconfig - Build generic kernel for MIPS64 r1
64r1el_defconfig - Build generic kernel for MIPS64 r1 little endian
64r2_defconfig - Build generic kernel for MIPS64 r2
64r2el_defconfig - Build generic kernel for MIPS64 r2 little endian
64r6_defconfig - Build generic kernel for MIPS64 r6
64r6el_defconfig - Build generic kernel for MIPS64 r6 little endian
micro32r2_defconfig - Build generic kernel for microMIPS32 r2
micro32r2el_defconfig - Build generic kernel for microMIPS32 r2 little endian
The following legacy default configurations have been converted to
generic and can still be used:
sead3_defconfig - Build 32r2el_defconfig BOARDS=sead-3
sead3micro_defconfig - Build micro32r2el_defconfig BOARDS=sead-3
xilfpga_defconfig - Build 32r2el_defconfig BOARDS=xilfpga
...
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kbuild@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/18598/
Now that arch/metag/ has been removed, remove the two metag irqchip
drivers. They are of no value without the architecture code.
- irq-metag: Meta internal (HWSTATMETA) interrupt code.
- irq-metag-ext: Meta External interrupt code.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-metag@vger.kernel.org
The earliest Meta architecture port of Linux I have a record of was an
import of a Meta port of Linux v2.4.1 in February 2004, which was worked
on significantly over the next few years by Graham Whaley, Will Newton,
Matt Fleming, myself and others.
Eventually the port was merged into mainline in v3.9 in March 2013, not
long after Imagination Technologies bought MIPS Technologies and shifted
its CPU focus over to the MIPS architecture.
As a result, though the port was maintained for a while, kept on life
support for a while longer, and useful for testing a few specific
drivers for which I don't have ready access to the equivalent MIPS
hardware, it is now essentially dead with no users.
It is also stuck using an out-of-tree toolchain based on GCC 4.2.4 which
is no longer maintained, now struggles to build modern kernels due to
toolchain bugs, and doesn't itself build with a modern GCC. The latest
buildroot port is still using an old uClibc snapshot which is no longer
served, and the latest uClibc doesn't build with GCC 4.2.4.
So lets call it a day and drop the Meta architecture port from the
kernel. RIP Meta.
Signed-off-by: James Hogan <jhogan@kernel.org>
Link: https://lkml.kernel.org/r/95906b76-6ce1-3f84-eaba-c29b4ae952eb@roeck-us.net
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Graham Whaley <graham.whaley@gmail.com>
Cc: linux-metag@vger.kernel.org
MIPS' struct compat_flock doesn't match the 32-bit struct flock, as it
has an extra short __unused before pad[4], which combined with alignment
increases the size to 40 bytes compared with struct flock's 36 bytes.
Since commit 8c6657cb50 ("Switch flock copyin/copyout primitives to
copy_{from,to}_user()"), put_compat_flock() writes the full compat_flock
struct to userland, which results in corruption of the userland word
after the struct flock when running 32-bit userlands on 64-bit kernels.
This was observed to cause a bus error exception when starting Firefox
on Debian 8 (Jessie).
Reported-by: Peter Mamonov <pmamonov@gmail.com>
Signed-off-by: James Hogan <jhogan@kernel.org>
Tested-by: Peter Mamonov <pmamonov@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.13+
Patchwork: https://patchwork.linux-mips.org/patch/18646/
Move the Kconfig symbols USB_UHCI_BIG_ENDIAN_MMIO and
USB_UHCI_BIG_ENDIAN_DESC out of drivers/usb/host/Kconfig, which is
conditional upon USB && USB_SUPPORT, so that it can be freely selected
by platform Kconfig symbols in architecture code.
For example once the MIPS_GENERIC platform selects are fixed in commit
2e6522c565 ("MIPS: Fix typo BIG_ENDIAN to CPU_BIG_ENDIAN"), the MIPS
32r6_defconfig warns like so:
warning: (MIPS_GENERIC) selects USB_UHCI_BIG_ENDIAN_MMIO which has unmet direct dependencies (USB_SUPPORT && USB)
warning: (MIPS_GENERIC) selects USB_UHCI_BIG_ENDIAN_DESC which has unmet direct dependencies (USB_SUPPORT && USB)
Fixes: 2e6522c565 ("MIPS: Fix typo BIG_ENDIAN to CPU_BIG_ENDIAN")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Corentin Labbe <clabbe.montjoie@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-usb@vger.kernel.org
Cc: linux-mips@linux-mips.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Patchwork: https://patchwork.linux-mips.org/patch/18559/
Commit 17278a91e0 ("MIPS: CPS: Fix r1 .set mt assembler warning")
added .set MIPS_ISA_LEVEL_RAW to silence warnings about .set mt on r1,
however this can result in a MOVE being encoded as a 64-bit DADDU
instruction on certain version of binutils (e.g. 2.22), and reserved
instruction exceptions at runtime on 32-bit hardware.
Reduce the sizes of the push/pop sections to include only instructions
that are part of the MT ASE or which won't convert to 64-bit
instructions after .set mips64r2/mips64r6.
Reported-by: Greg Ungerer <gerg@linux-m68k.org>
Fixes: 17278a91e0 ("MIPS: CPS: Fix r1 .set mt assembler warning")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.15
Tested-by: Greg Ungerer <gerg@linux-m68k.org>
Patchwork: https://patchwork.linux-mips.org/patch/18578/
We now have a platform (Ranchu) in the "generic" platform which matches
based on the FDT compatible string using mips_machine_is_compatible(),
however that function doesn't stop at a blank struct
of_device_id::compatible as that is an array in the struct, not a
pointer to a string.
Fix the loop completion to check the first byte of the compatible array
rather than the address of the compatible array in the struct.
Fixes: eed0eabd12 ("MIPS: generic: Introduce generic DT-based board support")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Reviewed-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18580/
ipmr_vif_seq_show() prints the difference between two pointers with the
format string %2zd (z for size_t), however the correct format string is
%2td instead (t for ptrdiff_t).
The same bug in ip6mr_vif_seq_show() was already fixed long ago by
commit d430a227d2 ("bogus format in ip6mr").
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Update MSA control register access helpers to use the new helpers for
parsing register names and creating custom assembly macro instructions.
This allows the move via $at to be dropped (saving a total of about 20
bytes of kernel code).
Note, this does not alter the equivalent code in .S files, which still
uses the $at trick.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17776/
Now that we are using assembler macros to implement XPA instructions on
toolchains which don't support them, pass Cop0 register names to the
__{readx,writex}_32bit_c0_register macros in $n format rather than
register numbers. Also pass a register select which may be useful in
future (for example for MemoryMapID field of WatchHi registers on
I6500).
This is to make them consistent with the normal Cop0 register access
macros which they were originally based on.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17777/
Utilise XPA instructions MFHC0 & MTHC0 in inline assembly instead of
directly encoding them with the _ASM_INSN* macros, and transparently
implement these instructions as assembler macros if the toolchain
doesn't support them natively, using the recently introduced assembler
macro helpers.
The old direct encodings were restricted to using the register $at, so
this allows the extra register moves to go away (saving a grand total of
24 bytes).
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17775/
Now that we are using assembler macros to implement VZ instructions on
toolchains which don't support them, pass VZ guest Cop0 register names
to the __{read,write}_{32bit,ulong,64bit}_gc0_register macros in $n
format rather than register numbers. This is to make them consistent
with the normal root Cop0 register access macros which they were
originally based on.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17773/
Update VZ guest register & guest TLB access helpers to use the new
assembly macros for parsing register names and creating custom assembly
macro instructions, which has a number of advantages:
- Better code can be generated on toolchains which don't support VZ,
more closely matching those which do, since there is no need to
bounce values via the $at register. Some differences still remain due
to the inability to safely fill branch delay slots and R6 compact
branch forbidden slots with explicitly encoded instructions,
resulting in some extra NOPs added by the assembler.
- Some code duplication between toolchains which do and don't support
VZ instructions is removed, since the helpers are only implemented
once. When the toolchain doesn't implement the instruction an
assembly macro implements it instead.
- Instruction encodings are kept together in the source.
On a generic kernel with KVM VZ support enabled this change saves about
2.5KiB of kernel code when TOOLCHAIN_SUPPORTS_VIRT=n, bringing it down
to about 0.5KiB more than when TOOLCHAIN_SUPPORTS_VIRT=y on r6, and just
68 bytes more on r2.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17772/
Implement a parse_r assembler macro in asm/mipsregs.h to parse a
register in $n form, and a few C macros for defining assembler macro
instructions. These can be used to more transparently support older
binutils versions which don't support for example the msa, virt, xpa, or
crc instructions.
In particular they overcome the difficulty of turning a register name in
$n form into an instruction encoding suitable for giving to .word /
.hword, which is particularly problematic when needed from inline
assembly where the compiler is responsible for register allocation.
Traditionally this had required the use of $at and an extra MOV
instruction, but for CRC instructions with multiple GP register operands
that approach becomes more difficult.
Three assembler macro creation helpers are added:
- _ASM_MACRO_0(OP, ENC)
This is to define an assembler macro for an instruction which has no
operands, for example the VZ TLBGR instruction.
- _ASM_MACRO_2R(OP, R1, R2, ENC)
This is to define an assembler macro for an instruction which has 2
register operands, for example the CFCMSA instruction.
- _ASM_MACRO_3R(OP, R1, R2, R3, ENC)
This is to define an assembler macro for an instruction which has 3
register operands, for example the crc32 instructions.
- _ASM_MACRO_2R_1S(OP, R1, R2, SEL3, ENC)
This is to define an assembler macro for a Cop0 move instruction,
with 2 register operands and an optional register select operand
which defaults to 0, for example the VZ MFGC0 instruction.
Suggested-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Marcin Nowakowski <marcin.nowakowski@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17770/
Since commit d41e6858ba ("MIPS: Kconfig: Set default MIPS system type
as generic") switched the default platform to the "generic" platform,
allmodconfig has been failing with the following linker error (among
other errors):
arch/mips/kernel/vpe-mt.o In function `vpe_run':
(.text+0x59c): undefined reference to `physical_memsize'
The Lantiq platform already worked around the same issue in commit
9050d50e22 ("MIPS: lantiq: Set physical_memsize") by declaring
physical_memsize with the initial value of 0 (on the assumption that the
actual memory size will be hard-coded in the loaded VPE firmware), and
the Malta platform already provided physical_memsize.
Since all other platforms will fail to link with the VPE loader enabled,
only allow Lantiq and Malta platforms to enable it, by way of a
SYS_SUPPORTS_VPE_LOADER which is selected by those two platforms and
which MIPS_VPE_LOADER depends on. SYS_SUPPORTS_MULTITHREADING is now a
dependency of SYS_SUPPORTS_VPE_LOADER so that Kconfig emits a warning if
SYS_SUPPORTS_VPE_LOADER is selected without SYS_SUPPORTS_MULTITHREADING.
Fixes: d41e6858ba ("MIPS: Kconfig: Set default MIPS system type as generic")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Crispin <john@phrozen.org>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-mips@linux-mips.org
Tested-by: Guenter Roeck <linux@roeck-us.net>
Patchwork: https://patchwork.linux-mips.org/patch/18453/
Since commit d41e6858ba ("MIPS: Kconfig: Set default MIPS system type
as generic") changed the default MIPS platform to the "generic"
platform, which uses PCI_DRIVERS_GENERIC instead of PCI_DRIVERS_LEGACY,
various files in drivers/ssb/ have failed to build.
This is particularly due to the existence of struct pci_controller being
dependent on PCI_DRIVERS_LEGACY since commit c5611df968 ("MIPS: PCI:
Introduce CONFIG_PCI_DRIVERS_LEGACY"), so add that dependency to Kconfig
to prevent these files being built for the "generic" platform including
all{yes,mod}config builds.
Fixes: c5611df968 ("MIPS: PCI: Introduce CONFIG_PCI_DRIVERS_LEGACY")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Michael Buesch <m@bues.ch>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-wireless@vger.kernel.org
Cc: linux-mips@linux-mips.org
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
GCC7 is a bit too eager to generate suboptimal __multi3 calls (128bit
multiply with 128bit result) for MIPS64r6 builds, even in code which
doesn't explicitly use 128bit types, such as the following:
unsigned long func(unsigned long a, unsigned long b)
{
return a > (~0UL) / b;
}
Which GCC rearanges to:
return (unsigned __int128)a * (unsigned __int128)b > 0xffffffffffffffff;
Therefore implement __multi3, but only for MIPS64r6 with GCC7 as under
normal circumstances we wouldn't expect any calls to __multi3 to be
generated from kernel code.
Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: James Hogan <jhogan@kernel.org>
Tested-by: Waldemar Brodkorb <wbx@openadk.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Maciej W. Rozycki <macro@mips.com>
Cc: Matthew Fortune <matthew.fortune@mips.com>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17890/
Since commit 68923cdc2e ("MIPS: CM: Add cluster & block args to
mips_cm_lock_other()"), mips_smp_send_ipi_mask() has used
mips_cm_lock_other_cpu() with each CPU number, rather than
mips_cm_lock_other() with the first VPE in each core. Prior to r6,
multicore multithreaded systems such as dual-core dual-thread
interAptivs with CPU Idle enabled (e.g. MIPS Creator Ci40) results in
mips_cm_lock_other() repeatedly hitting WARN_ON(vp != 0).
There doesn't appear to be anything fundamentally wrong about passing a
non-zero VP/VPE number, even if it is a core's region that is locked
into the other region before r6, so remove that particular WARN_ON().
Fixes: 68923cdc2e ("MIPS: CM: Add cluster & block args to mips_cm_lock_other()")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 4.14+
Patchwork: https://patchwork.linux-mips.org/patch/17883/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The MIPS_CPS_NS16550_BASE and MIPS_CPS_NS16550_SHIFT options have no
defaults for non-Malta platforms which select SYS_SUPPORTS_MIPS_CPS
(i.e. the pistachio and generic platforms). This is problematic for
automated allyesconfig and allmodconfig builds based on these platforms,
since make silentoldconfig tries to ask the user for values, and
especially since v4.15 where the default platform was switched to
generic.
Default these options to 0 and arrange for MIPS_CPS_NS16550 to be no
when using that default base address, so that the option only has an
effect when the default is provided (i.e. Malta) or when a value is
provided by the user.
Fixes: 609cf6f229 ("MIPS: CPS: Early debug using an ns16550-compatible UART")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17749/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Make read_c0_prid() use the new constant accessor macros so that it can
potentially be optimised or removed by the compiler. This is
particularly important under virtualisation, where even with hardware
assisted virtualisation (VZ), access to the PRid register may need to be
emulated by the hypervisor.
In particular this helps eliminate the read of the PRid register in the
rather frequently called add_interrupt_randomness() (which calls into
arch/mips/include/asm/timex.h) when the prid is unused but the read
can't be removed due to the inline asm being marked __volatile__.
Reported-by: Yann LeDu <Yann.LeDu@imgtec.com>
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Maciej W. Rozycki <macro@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17923/
Some Cop0 registers are constant and have no side effects when read.
There is no need for the inline asm to read these to be marked
__volatile__, and doing so prevents them from being removed by the
compiler.
Add a few new accessor macros to handle these registers more efficiently
(especially for the sake of running in a guest where redundant access to
the register may trap to the hypervisor):
__read_const_32bit_c0_register()
__read_const_64bit_c0_register()
__read_const_ulong_c0_register()
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Maciej W. Rozycki <macro@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17922/
Current MIPS64r6 toolchains aren't able to generate efficient
DMULU/DMUHU based code for the C implementation of umul_ppmm(), which
performs an unsigned 64 x 64 bit multiply and returns the upper and
lower 64-bit halves of the 128-bit result. Instead it widens the 64-bit
inputs to 128-bits and emits a __multi3 intrinsic call to perform a 128
x 128 multiply. This is both inefficient, and it results in a link error
since we don't include __multi3 in MIPS linux.
For example commit 90a53e4432 ("cfg80211: implement regdb signature
checking") merged in v4.15-rc1 recently broke the 64r6_defconfig and
64r6el_defconfig builds by indirectly selecting MPILIB. The same build
errors can be reproduced on older kernels by enabling e.g. CRYPTO_RSA:
lib/mpi/generic_mpih-mul1.o: In function `mpihelp_mul_1':
lib/mpi/generic_mpih-mul1.c:50: undefined reference to `__multi3'
lib/mpi/generic_mpih-mul2.o: In function `mpihelp_addmul_1':
lib/mpi/generic_mpih-mul2.c:49: undefined reference to `__multi3'
lib/mpi/generic_mpih-mul3.o: In function `mpihelp_submul_1':
lib/mpi/generic_mpih-mul3.c:49: undefined reference to `__multi3'
lib/mpi/mpih-div.o In function `mpihelp_divrem':
lib/mpi/mpih-div.c:205: undefined reference to `__multi3'
lib/mpi/mpih-div.c:142: undefined reference to `__multi3'
Therefore add an efficient MIPS64r6 implementation of umul_ppmm() using
inline assembly and the DMULU/DMUHU instructions, to prevent __multi3
calls being emitted.
Fixes: 7fd08ca58a ("MIPS: Add build support for the MIPS R6 ISA")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-mips@linux-mips.org
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fix an uninitialized variable warning in the Octeon EDAC driver, as seen
in MIPS cavium_octeon_defconfig builds since v4.14 with Codescape GNU
Tools 2016.05-03:
drivers/edac/octeon_edac-lmc.c In function ‘octeon_lmc_edac_poll_o2’:
drivers/edac/octeon_edac-lmc.c:87:24: warning: ‘((long unsigned int*)&int_reg)[1]’ may \
be used uninitialized in this function [-Wmaybe-uninitialized]
if (int_reg.s.sec_err || int_reg.s.ded_err) {
^
Iinitialise the whole int_reg variable to zero before the conditional
assignments in the error injection case.
Signed-off-by: James Hogan <jhogan@kernel.org>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15+
Fixes: 1bc021e815 ("EDAC: Octeon: Add error injection support")
Link: http://lkml.kernel.org/r/20171113161206.20990-1-james.hogan@mips.com
Signed-off-by: Borislav Petkov <bp@suse.de>
The MIPS loongson cpufreq drivers don't build unless configured for the
correct machine type, due to dependency on machine specific architecture
headers and symbols in machine specific platform code.
More specifically loongson1-cpufreq.c uses RST_CPU_EN and RST_CPU,
neither of which is defined in asm/mach-loongson32/regs-clk.h unless
CONFIG_LOONGSON1_LS1B=y, and loongson2_cpufreq.c references
loongson2_clockmod_table[], which is only defined in
arch/mips/loongson64/lemote-2f/clock.c, i.e. when
CONFIG_LEMOTE_MACH2F=y.
Add these dependencies to Kconfig to avoid randconfig / allyesconfig
build failures (e.g. when based on BMIPS which also has a cpufreq
driver).
Signed-off-by: James Hogan <jhogan@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Building 32-bit MIPS64r2 kernels produces warnings like the following
on certain toolchains (such as GNU assembler 2.24.90, but not GNU
assembler 2.28.51) since commit 22b8ba765a ("MIPS: Fix MIPS64 FP
save/restore on 32-bit kernels"), due to the exposure of fpu_save_16odd
from fpu_save_double and fpu_restore_16odd from fpu_restore_double:
arch/mips/kernel/r4k_fpu.S:47: Warning: float register should be even, was 1
...
arch/mips/kernel/r4k_fpu.S:59: Warning: float register should be even, was 1
...
This appears to be because .set mips64r2 does not change the FPU ABI to
64-bit when -march=mips64r2 (or e.g. -march=xlp) is provided on the
command line on that toolchain, from the default FPU ABI of 32-bit due
to the -mabi=32. This makes access to the odd FPU registers invalid.
Fix by explicitly changing the FPU ABI with .set fp=64 directives in
fpu_save_16odd and fpu_restore_16odd, and moving the undefine of fp up
in asmmacro.h so fp doesn't turn into $30.
Fixes: 22b8ba765a ("MIPS: Fix MIPS64 FP save/restore on 32-bit kernels")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.0+: 22b8ba765a: MIPS: Fix MIPS64 FP save/restore on 32-bit kernels
Cc: <stable@vger.kernel.org> # 4.0+
Patchwork: https://patchwork.linux-mips.org/patch/17656/
Update the thread_info::syscall field when registers are modified via
ptrace to change or cancel the system call being entered.
This is important to allow seccomp and the syscall entry and exit trace
events to observe the new syscall number changed by the normal ptrace
hook or seccomp. That includes allowing seccomp's recheck of the system
call number after SECCOMP_RET_TRACE to notice if the syscall is changed
to a denied one, which happens in seccomp since commit ce6526e8af
("seccomp: recheck the syscall after RET_TRACE") in v4.8.
In the process of doing this, the logic to determine whether an indirect
system call is in progress (i.e. the O32 ABI's syscall()) is abstracted
into mips_syscall_is_indirect(), and a new mips_syscall_update_nr() is
used to update the thread_info::syscall based on the register state.
The following ptrace operations are updated:
- PTRACE_SETREGS (ptrace_setregs()).
- PTRACE_SETREGSET with NT_PRSTATUS (gpr32_set() and gpr64_set()).
- PTRACE_POKEUSR with 2/v0 or 4/a0 for indirect syscall
([compat_]arch_ptrace()).
Fixes: c2d9f17757 ("MIPS: Fix syscall_get_nr for the syscall exit tracing.")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Lars Persson <larper@axis.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16995/
The MIPS syscall_trace_enter() allows the system call number to be
altered or cancelled by a ptrace tracer, via the normal ptrace hook
(PTRACE_SYSCALL) and changing the system call number register on entry,
and similarly via seccomp (PTRACE_EVENT_SECCOMP when a seccomp filter
returns SECCOMP_RET_TRACE).
Be sure to update the syscall local variable if this happens, so that
seccomp will filter the correct system call number if the normal ptrace
hook changes it first, and so that if either the normal ptrace hook or
seccomp change it the correct system call number is passed to the trace
event.
This won't have any effect until the next commit, which fixes ptrace to
update thread_info::syscall.
Fixes: c2d9f17757 ("MIPS: Fix syscall_get_nr for the syscall exit tracing.")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Lars Persson <lars.persson@axis.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16996/
32-bit kernels can be configured to support MIPS64, in which case
neither CONFIG_64BIT or CONFIG_CPU_MIPS32_R* will be set. This causes
the CP0_Status.FR checks at the point of floating point register save
and restore to be compiled out, which results in odd FP registers not
being saved or restored to the task or signal context even when
CP0_Status.FR is set.
Fix the ifdefs to use CONFIG_CPU_MIPSR2 and CONFIG_CPU_MIPSR6, which are
enabled for the relevant revisions of either MIPS32 or MIPS64, along
with some other CPUs such as Octeon (r2), Loongson1 (r2), XLP (r2),
Loongson 3A R2.
The suspect code originates from commit 597ce1723e ("MIPS: Support for
64-bit FP with O32 binaries") in v3.14, however the code in
__enable_fpu() was consistent and refused to set FR=1, falling back to
software FPU emulation. This was suboptimal but should be functionally
correct.
Commit fcc53b5f6c ("MIPS: fpu.h: Allow 64-bit FPU on a 64-bit MIPS R6
CPU") in v4.2 (and stable tagged back to 4.0) later introduced the bug
by updating __enable_fpu() to set FR=1 but failing to update the other
similar ifdefs to enable FR=1 state handling.
Fixes: fcc53b5f6c ("MIPS: fpu.h: Allow 64-bit FPU on a 64-bit MIPS R6 CPU")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.0+
Patchwork: https://patchwork.linux-mips.org/patch/16739/
Building an allnoconfig kernel based on the ralink platform results in
the following warning:
warning: (SOC_RT305X) selects USB_ARCH_HAS_HCD which has unmet direct dependencies (USB_SUPPORT)
This is because SOC_RT305X unconditionally selects USB_ARCH_HAS_HCD
which depends on USB_SUPPORT.
However USB_ARCH_HAS_HCD has been effectively obsolete since commit
d9ea21a779 ("usb: host: make USB_ARCH_HAS_?HCI obsolete") in 3.11.
USB_ARCH_HAS_HCD is now set by default whenever USB_SUPPORT is, so drop
the select to silence the warning.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Crispin <john@phrozen.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17618/
The smp-cmp build has been (further) broken since commit 856fbcee60
("MIPS: Store core & VP IDs in GlobalNumber-style variable") in
v4.14-rc1 like so:
arch/mips/kernel/smp-cmp.c: In function ‘cmp_init_secondary’:
arch/mips/kernel/smp-cmp.c:53:4: error: ‘struct cpuinfo_mips’ has no member named ‘vpe_id’
c->vpe_id = (read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) &
^
Fix by replacing vpe_id with cpu_set_vpe_id().
Fixes: 856fbcee60 ("MIPS: Store core & VP IDs in GlobalNumber-style variable")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17569/
Signed-off-by: James Hogan <jhogan@kernel.org>
Since commit 04a85e087a ("MIPS: generic: Move NI 169445 FIT image
source to its own file"), a generic 32r2el_defconfig kernel fails to
build with the following build error:
ITB arch/mips/boot/vmlinux.gz.itb
Error: arch/mips/boot/vmlinux.gz.its:111.1-2 syntax error
FATAL ERROR: Unable to parse input tree
mkimage Can't read arch/mips/boot/vmlinux.gz.itb.tmp: Invalid argument
Fix arch/mips/generic/board-ni169445.its.S to include the necessary "/"
node path before the first open brace.
The original issue in arch/mips/generic/vmlinux.its.S was fixed directly
in the original commit 7aacf86b75 ("MIPS: NI 169445 board support")
after https://patchwork.linux-mips.org/patch/16941/ was submitted, but
the separate its.S file wasn't correctly fixed when resolving the
conflict in commit 04a85e087a ("MIPS: generic: Move NI 169445 FIT
image source to its own file").
Fixes: 04a85e087a ("MIPS: generic: Move NI 169445 FIT image source to its own file")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Nathan Sullivan <nathan.sullivan@ni.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17561/
Signed-off-by: James Hogan <jhogan@kernel.org>
When CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST=n, the call path
hrtimer_reprogram -> clockevents_program_event ->
clockevents_program_min_delta will not retry if the clock event driver
returns -ETIME.
If the driver could not satisfy the program_min_delta for any reason, the
lack of a retry means the CPU may not receive a tick interrupt, potentially
until the counter does a full period. This leads to rcu_sched timeout
messages as the stalled CPU is detected by other CPUs, and other issues if
the CPU is holding locks or other resources at the point at which it
stalls.
There have been a couple of observed mechanisms through which a clock event
driver could not satisfy the requested min_delta and return -ETIME.
With the MIPS GIC driver, the shared execution resource within MT cores
means inconventient latency due to execution of instructions from other
hardware threads in the core, within gic_next_event, can result in an event
being set in the past.
Additionally under virtualisation it is possible to get unexpected latency
during a clockevent device's set_next_event() callback which can make it
return -ETIME even for a delta based on min_delta_ns.
It isn't appropriate to use MIN_ADJUST in the virtualisation case as
occasional hypervisor induced high latency will cause min_delta_ns to
quickly increase to the maximum.
Instead, borrow the retry pattern from the MIN_ADJUST case, but without
making adjustments. Retry up to 10 times, each time increasing the
attempted delta by min_delta, before giving up.
[ Matt: Reworked the loop and made retry increase the delta. ]
Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: "Martin Schwidefsky" <schwidefsky@de.ibm.com>
Cc: James Hogan <james.hogan@mips.com>
Link: https://lkml.kernel.org/r/1508422643-6075-1-git-send-email-matt.redfearn@mips.com
Update my imgtec.com and personal email address to my kernel.org one in
a few places as MIPS will soon no longer be part of Imagination
Technologies, and add mappings in .mailcap so get_maintainer.pl reports
the right address.
Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The inline asm in __write_64bit_c0_split() modifies the 64-bit input
operand by shifting the high register left by 32, and constructing the
full 64-bit value in the low register (even on a 32-bit kernel), so if
that value is used again it could cause breakage as GCC would assume the
registers haven't changed when they have.
To quote the GCC extended asm documentation:
> Warning: Do not modify the contents of input-only operands (except for
> inputs tied to outputs). The compiler assumes that on exit from the
> asm statement these operands contain the same values as they had
> before executing the statement.
Avoid modifying the input by using a temporary variable as an output
which is modified instead of the input and not otherwise used. The asm
is always __volatile__ so GCC shouldn't optimise it out. The low
register of the temporary output is written before the high register of
the input is read, so we have two constraint alternatives, one where
both use the same registers (for when the input value isn't subsequently
used), and one with an early clobber on the output in case the low
output uses the same register as the high input. This allows the
resulting assembly to remain mostly unchanged.
A diff of a MIPS32r6 kernel reveals only three differences, two in
relation to write_c0_r10k_diag() in cpu_probe() (register allocation
rearranged slightly but otherwise identical), and one in relation to
write_c0_cvmmemctl2() in kvm_vz_local_flush_guesttlb_all(), but the
octeon CPU is only supported on 64-bit kernels where
__write_64bit_c0_split() isn't used so that shouldn't matter in
practice. So there currently doesn't appear to be anything broken by
this bug.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17315/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
A SYNC is required between enabling the GIC region and actually trying
to use it, even if the first access is a read, otherwise its possible
depending on the timing (and in my case depending on the precise
alignment of certain kernel code) to hit CM bus errors on that first
access.
Add the SYNC straight after setting the GIC base.
[paul.burton@imgtec.com:
Changes later in this series increase our likelihood of hitting this
by reducing the amount of code that runs between enabling the GIC &
accessing it.]
Fixes: a7057270c2 ("irqchip: mips-gic: Add device-tree support")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17019/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 669c409222 ("MIPS: Give __secure_computing() access to
syscall arguments."), upon syscall entry when seccomp is enabled,
syscall_trace_enter() passes a carefully prepared struct seccomp_data
containing syscall arguments to __secure_computing(). Unfortunately it
directly uses mips_get_syscall_arg() and fails to take into account the
indirect O32 system calls (i.e. syscall(2)) which put the system call
number in a0 and have the arguments shifted up by one entry.
We can't just revert that commit as samples/bpf/tracex5 would break
again, so use syscall_get_arguments() which already takes indirect
syscalls into account instead of directly using mips_get_syscall_arg(),
similar to what populate_seccomp_data() does.
This also removes the redundant error checking of the
mips_get_syscall_arg() return value (get_user() already zeroes the
result if an argument from the stack can't be loaded).
Reported-by: James Cowgill <James.Cowgill@imgtec.com>
Fixes: 669c409222 ("MIPS: Give __secure_computing() access to syscall arguments.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16994/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 64e2a42bca ("parisc: Add ARCH_TRACEHOOK and regset
support") in v4.7, parisc selects HAVE_ARCH_TRACEHOOK, so update its
entry in Documentation/features from TODO to ok.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
If a negative system call number is used when system call tracing is
enabled, syscall_trace_enter() will return that negative system call
number without having written the return value and error flag into the
pt_regs.
The caller then treats it as a cancelled system call and assumes that
the return value and error flag are already written, leaving the
negative system call number in the return register ($v0), and the 4th
system call argument in the error register ($a3).
Add a special case to detect this at the end of syscall_trace_enter(),
to set the return value to error -ENOSYS when this happens.
Fixes: d218af7849 ("MIPS: scall: Always run the seccomp syscall filters")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16653/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When the system call return value is forced to be an error (for example
due to SECCOMP_RET_ERRNO), syscall_set_return_value() puts the error
code in the return register $v0 and -1 in the error register $a3.
However normally executed system calls put 1 in the error register
rather than -1, so fix syscall_set_return_value() to be consistent with
that.
I don't anticipate that anything would have been broken by this, since
the most natural way to check the error register on MIPS would be a
conditional branch if error register is [not] equal to zero (bnez or
beqz).
Fixes: 1d7bf993e0 ("MIPS: ftrace: Add support for syscall tracepoints.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16652/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The sys_exit trace event takes a single return value for the system
call, which MIPS passes the value of the $v0 (result) register, however
MIPS returns positive error codes in $v0 with $a3 specifying that $v0
contains an error code. As a result erroring system calls are traced
returning positive error numbers that can't always be distinguished from
success.
Use regs_return_value() to negate the error code if $a3 is set.
Fixes: 1d7bf993e0 ("MIPS: ftrace: Add support for syscall tracepoints.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.13+
Patchwork: https://patchwork.linux-mips.org/patch/16651/
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS selects HAVE_SYSCALL_TRACEPOINTS twice. The first was added back in
v3.13 by commit 2d7bf993e073 ("MIPS: ftrace: Add support for syscall
tracepoints."), but then a second redundant one was added in v4.2 by
commit fb59e394c3 ("MIPS: ftrace: Enable support for syscall
tracepoints.").
Drop the duplicate select.
Fixes: fb59e394c3 ("MIPS: ftrace: Enable support for syscall tracepoints.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16654/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 81a76d7119 ("MIPS: Avoid using unwind_stack() with
usermode") show_backtrace() invokes the raw backtracer when
cp0_status & ST0_KSU indicates user mode to fix issues on EVA kernels
where user and kernel address spaces overlap.
However this is used by show_stack() which creates its own pt_regs on
the stack and leaves cp0_status uninitialised in most of the code paths.
This results in the non deterministic use of the raw back tracer
depending on the previous stack content.
show_stack() deals exclusively with kernel mode stacks anyway, so
explicitly initialise regs.cp0_status to KSU_KERNEL (i.e. 0) to ensure
we get a useful backtrace.
Fixes: 81a76d7119 ("MIPS: Avoid using unwind_stack() with usermode")
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/16656/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The MIPS sysmips system call handler may return directly from the
MIPS_ATOMIC_SET case (mips_atomic_set()) to syscall_exit. This path
restores the static (callee saved) registers, however they won't have
been saved on entry to the system call.
Use the save_static_function() macro to create a __sys_sysmips wrapper
function which saves the static registers before calling sys_sysmips, so
that the correct static register state is restored by syscall_exit.
Fixes: f1e39a4a61 ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16149/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The inline asm retry check in the MIPS_ATOMIC_SET operation of the
sysmips system call has been backwards since commit f1e39a4a61 ("MIPS:
Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
merged in v2.6.32, resulting in the non R10000_LLSC_WAR case retrying
until the operation was inatomic, before returning the new value that
was probably just written multiple times instead of the old value.
Invert the branch condition to fix that particular issue.
Fixes: f1e39a4a61 ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16148/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The increment of entry in the loop in mmu_init for meta1 is redundant as
it isn't used again, so drop it.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
The metag implementation of strncpy_from_user() doesn't validate the src
pointer, which could allow reading of arbitrary kernel memory. Add a
short access_ok() check to prevent that.
Its still possible for it to read across the user/kernel boundary, but
it will invariably reach a NUL character after only 9 bytes, leaking
only a static kernel address being loaded into D0Re0 at the beginning of
__start, which is acceptable for the immediate fix.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
The __user_bad() macro used by access_ok() has a few corner cases
noticed by Al Viro where it doesn't behave correctly:
- The kernel range check has off by 1 errors which permit access to the
first and last byte of the kernel mapped range.
- The kernel range check ends at LINCORE_BASE rather than
META_MEMORY_LIMIT, which is ineffective when the kernel is in global
space (an extremely uncommon configuration).
There are a couple of other shortcomings here too:
- Access to the whole of the other address space is permitted (i.e. the
global half of the address space when the kernel is in local space).
This isn't ideal as it could theoretically still contain privileged
mappings set up by the bootloader.
- The size argument is unused, permitting user copies which start on
valid pages at the end of the user address range and cross the
boundary into the kernel address space (e.g. addr = 0x3ffffff0, size
> 0x10).
It isn't very convenient to add size checks when disallowing certain
regions, and it seems far safer to be sure and explicit about what
userland is able to access, so invert the logic to allow certain regions
instead, and fix the off by 1 errors and missing size checks. This also
allows the get_fs() == KERNEL_DS check to be more easily optimised into
the user address range case.
We now have 3 such allowed regions:
- The user address range (incorporating the get_fs() == KERNEL_DS
check).
- NULL (some kernel code expects this to work, and we'll always catch
the fault anyway).
- The core code memory region.
Fixes: 373cd784d0 ("metag: Memory handling")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
KGDB is a kernel debug stub and it can't be used to debug userland as it
can only safely access kernel memory.
On MIPS however KGDB has always got the register state of sleeping
processes from the userland register context at the beginning of the
kernel stack. This is meaningless for kernel threads (which never enter
userland), and for user threads it prevents the user seeing what it is
doing while in the kernel:
(gdb) info threads
Id Target Id Frame
...
3 Thread 2 (kthreadd) 0x0000000000000000 in ?? ()
2 Thread 1 (init) 0x000000007705c4b4 in ?? ()
1 Thread -2 (shadowCPU0) 0xffffffff8012524c in arch_kgdb_breakpoint () at arch/mips/kernel/kgdb.c:201
Get the register state instead from the (partial) kernel register
context stored in the task's thread_struct for resume() to restore. All
threads now correctly appear to be in context_switch():
(gdb) info threads
Id Target Id Frame
...
3 Thread 2 (kthreadd) context_switch (rq=<optimized out>, cookie=..., next=<optimized out>, prev=0x0) at kernel/sched/core.c:2903
2 Thread 1 (init) context_switch (rq=<optimized out>, cookie=..., next=<optimized out>, prev=0x0) at kernel/sched/core.c:2903
1 Thread -2 (shadowCPU0) 0xffffffff8012524c in arch_kgdb_breakpoint () at arch/mips/kernel/kgdb.c:201
Call clobbered registers which aren't saved and exception registers
(BadVAddr & Cause) which can't be easily determined without stack
unwinding are reported as 0. The PC is taken from the return address,
such that the state presented matches that found immediately after
returning from resume().
Fixes: 8854700115 ("[MIPS] kgdb: add arch support for the kernel's kgdb core")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15829/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
calculate_min_delta() may incorrectly access a 4th element of buf2[]
which only has 3 elements. This may trigger undefined behaviour and has
been reported to cause strange crashes in start_kernel() sometime after
timer initialization when built with GCC 5.3, possibly due to
register/stack corruption:
sched_clock: 32 bits at 200MHz, resolution 5ns, wraps every 10737418237ns
CPU 0 Unable to handle kernel paging request at virtual address ffffb0aa, epc == 8067daa8, ra == 8067da84
Oops[#1]:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.18 #51
task: 8065e3e0 task.stack: 80644000
$ 0 : 00000000 00000001 00000000 00000000
$ 4 : 8065b4d0 00000000 805d0000 00000010
$ 8 : 00000010 80321400 fffff000 812de408
$12 : 00000000 00000000 00000000 ffffffff
$16 : 00000002 ffffffff 80660000 806a666c
$20 : 806c0000 00000000 00000000 00000000
$24 : 00000000 00000010
$28 : 80644000 80645ed0 00000000 8067da84
Hi : 00000000
Lo : 00000000
epc : 8067daa8 start_kernel+0x33c/0x500
ra : 8067da84 start_kernel+0x318/0x500
Status: 11000402 KERNEL EXL
Cause : 4080040c (ExcCode 03)
BadVA : ffffb0aa
PrId : 0501992c (MIPS 1004Kc)
Modules linked in:
Process swapper/0 (pid: 0, threadinfo=80644000, task=8065e3e0, tls=00000000)
Call Trace:
[<8067daa8>] start_kernel+0x33c/0x500
Code: 24050240 0c0131f9 24849c64 <a200b0a8> 41606020 000000c0 0c1a45e6 00000000 0c1a5f44
UBSAN also detects the same issue:
================================================================
UBSAN: Undefined behaviour in arch/mips/kernel/cevt-r4k.c:85:41
load of address 80647e4c with insufficient space
for an object of type 'unsigned int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.18 #47
Call Trace:
[<80028f70>] show_stack+0x88/0xa4
[<80312654>] dump_stack+0x84/0xc0
[<8034163c>] ubsan_epilogue+0x14/0x50
[<803417d8>] __ubsan_handle_type_mismatch+0x160/0x168
[<8002dab0>] r4k_clockevent_init+0x544/0x764
[<80684d34>] time_init+0x18/0x90
[<8067fa5c>] start_kernel+0x2f0/0x500
=================================================================
buf2[] is intentionally only 3 elements so that the last element is the
median once 5 samples have been inserted, so explicitly prevent the
possibility of comparing against the 4th element rather than extending
the array.
Fixes: 1fa405552e ("MIPS: cevt-r4k: Dynamically calculate min_delta_ns")
Reported-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Tested-by: Rabin Vincent <rabinv@axis.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.7.x-
Patchwork: https://patchwork.linux-mips.org/patch/15892/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Switch to using raw user copy instead of providing metag specific
[__]copy_{to,from}_user[_inatomic](). This simplifies the metag
uaccess.h and allows us to take advantage of extra checking in the
generic versions.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-metag@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Metag already supports 64-bit put_user, so add support for 64-bit
get_user too so that the test_user_copy module can test both.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
The final fixup in the rapf loops must handle a corner case due to the
intermediate decrementing of the destination pointer before writing the
last element to it again and re-incrementing it. This decrement (and the
associated increment in the fixup code) can be easily avoided by using
SETL/SETD with an offset of -8/-4.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
The rapf copy loops in the Meta usercopy code is missing some extable
entries for HTP cores with unaligned access checking enabled, where
faults occur on the instruction immediately after the faulting access.
Add the fixup labels and extable entries for these cases so that corner
case user copy failures don't cause kernel crashes.
Fixes: 373cd784d0 ("metag: Memory handling")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
The fixup code to rewind the source pointer in
__asm_copy_from_user_{32,64}bit_rapf_loop() always rewound the source by
a single unit (4 or 8 bytes), however this is insufficient if the fault
didn't occur on the first load in the loop, as the source pointer will
have been incremented but nothing will have been stored until all 4
register [pairs] are loaded.
Read the LSM_STEP field of TXSTATUS (which is already loaded into a
register), a bit like the copy_to_user versions, to determine how many
iterations of MGET[DL] have taken place, all of which need rewinding.
Fixes: 373cd784d0 ("metag: Memory handling")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
The fixup code for the copy_to_user rapf loops reads TXStatus.LSM_STEP
to decide how far to rewind the source pointer. There is a special case
for the last execution of an MGETL/MGETD, since it leaves LSM_STEP=0
even though the number of MGETLs/MGETDs attempted was 4. This uses ADDZ
which is conditional upon the Z condition flag, but the AND instruction
which masked the TXStatus.LSM_STEP field didn't set the condition flags
based on the result.
Fix that now by using ANDS which does set the flags, and also marking
the condition codes as clobbered by the inline assembly.
Fixes: 373cd784d0 ("metag: Memory handling")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
Currently we try to zero the destination for a failed read from userland
in fixup code in the usercopy.c macros. The rest of the destination
buffer is then zeroed from __copy_user_zeroing(), which is used for both
copy_from_user() and __copy_from_user().
Unfortunately we fail to zero in the fixup code as D1Ar1 is set to 0
before the fixup code entry labels, and __copy_from_user() shouldn't even
be zeroing the rest of the buffer.
Move the zeroing out into copy_from_user() and rename
__copy_user_zeroing() to raw_copy_from_user() since it no longer does
any zeroing. This also conveniently matches the name needed for
RAW_COPY_USER support in a later patch.
Fixes: 373cd784d0 ("metag: Memory handling")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
When copying to userland on Meta, if any faults are encountered
immediately abort the copy instead of continuing on and repeatedly
faulting, and worse potentially copying further bytes successfully to
subsequent valid pages.
Fixes: 373cd784d0 ("metag: Memory handling")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
Fix the error checking of the alignment adjustment code in
raw_copy_from_user(), which mistakenly considers it safe to skip the
error check when aligning the source buffer on a 2 or 4 byte boundary.
If the destination buffer was unaligned it may have started to copy
using byte or word accesses, which could well be at the start of a new
(valid) source page. This would result in it appearing to have copied 1
or 2 bytes at the end of the first (invalid) page rather than none at
all.
Fixes: 373cd784d0 ("metag: Memory handling")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
Properly implement emulation of the TLBR instruction for Trap & Emulate.
This instruction reads the TLB entry pointed at by the CP0_Index
register into the other TLB registers, which may have the side effect of
changing the current ASID. Therefore abstract the CP0_EntryHi and ASID
changing code into a common function in the process.
A comment indicated that Linux doesn't use TLBR, which is true during
normal use, however dumping of the TLB does use it (for example with the
relatively recent 'x' magic sysrq key), as does a wired TLB entries test
case in my KVM tests.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Octeon III doesn't implement the optional GuestCtl0.CG bit to allow
guest mode to execute virtual address based CACHE instructions, so
implement emulation of a few important ones specifically for Octeon III
in response to a GPSI exception.
Currently the main reason to perform these operations is for icache
synchronisation, so they are implemented as a simple icache flush with
local_flush_icache_range().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Set up hardware virtualisation on Octeon III cores, configuring guest
interrupt routing and carving out half of the root TLB for guest use,
restoring it back again afterwards.
We need to be careful to inhibit TLB shutdown machine check exceptions
while invalidating guest TLB entries, since TLB invalidation is not
available so guest entries must be invalidated by setting them to unique
unmapped addresses, which could conflict with mappings set by the guest
or root if recently repartitioned.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Create a trace event for guest mode changes, and enable VZ's
GuestCtl0.MC bit after the trace event is enabled to trap all guest mode
changes.
The MC bit causes Guest Hardware Field Change (GHFC) exceptions whenever
a guest mode change occurs (such as an exception entry or return from
exception), so we need to handle this exception now. The MC bit is only
enabled when restoring register state, so enabling the trace event won't
take immediate effect.
Tracing guest mode changes can be particularly handy when trying to work
out what a guest OS gets up to before something goes wrong, especially
if the problem occurs as a result of some previous guest userland
exception which would otherwise be invisible in the trace.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Transfer timer state to the VZ guest context (CP0_GTOffset & guest
CP0_Count) when entering guest mode, enabling direct guest access to it,
and transfer back to soft timer when saving guest register state.
This usually allows guest code to directly read CP0_Count (via MFC0 and
RDHWR) and read/write CP0_Compare, without trapping to the hypervisor
for it to emulate the guest timer. Writing to CP0_Count or CP0_Cause.DC
is much less common and still triggers a hypervisor GPSI exception, in
which case the timer state is transferred back to an hrtimer before
emulating the write.
We are careful to prevent small amounts of drift from building up due to
undeterministic time intervals between reading of the ktime and reading
of CP0_Count. Some drift is expected however, since the system
clocksource may use a different timer to the local CP0_Count timer used
by VZ. This is permitted to prevent guest CP0_Count from appearing to go
backwards.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
When restoring guest state after another VCPU has run, be sure to clear
CP0_LLAddr.LLB in order to break any interrupted atomic critical
section. Without this SMP guest atomics don't work when LLB is present
as one guest can complete the atomic section started by another guest.
MIPS VZ guest read of CP0_LLAddr causes Guest Privileged Sensitive
Instruction (GPSI) exception due to the address being root physical.
Handle this by reporting only the LLB bit, which contains the bit for
whether a ll/sc atomic is in progress without any reason for failure.
Similarly on P5600 a guest write to CP0_LLAddr also causes a GPSI
exception. Handle this also by clearing the guest LLB bit from root
mode.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
James Hogan