Paul Burton [Tue, 4 Dec 2018 23:44:12 +0000 (23:44 +0000)]
MIPS: Expand MIPS32 ASIDs to 64 bits
ASIDs have always been stored as unsigned longs, ie. 32 bits on MIPS32
kernels. This is problematic because it is feasible for the ASID version
to overflow & wrap around to zero.
We currently attempt to handle this overflow by simply setting the ASID
version to 1, using asid_first_version(), but we make no attempt to
account for the fact that there may be mm_structs with stale ASIDs that
have versions which we now reuse due to the overflow & wrap around.
Encountering this requires that:
1) A struct mm_struct X is active on CPU A using ASID (V,n).
2) That mm is not used on CPU A for the length of time that it takes
for CPU A's asid_cache to overflow & wrap around to the same
version V that the mm had in step 1. During this time tasks using
the mm could either be sleeping or only scheduled on other CPUs.
3) Some other mm Y becomes active on CPU A and is allocated the same
ASID (V,n).
4) mm X now becomes active on CPU A again, and now incorrectly has the
same ASID as mm Y.
Where struct mm_struct ASIDs are represented above in the format
(version, EntryHi.ASID), and on a typical MIPS32 system version will be
24 bits wide & EntryHi.ASID will be 8 bits wide.
The length of time required in step 2 is highly dependent upon the CPU &
workload, but for a hypothetical 2GHz CPU running a workload which
generates a new ASID every 10000 cycles this period is around 248 days.
Due to this long period of time & the fact that tasks need to be
scheduled in just the right (or wrong, depending upon your inclination)
way, this is obviously a difficult bug to encounter but it's entirely
possible as evidenced by reports.
In order to fix this, simply extend ASIDs to 64 bits even on MIPS32
builds. This will extend the period of time required for the
hypothetical system above to encounter the problem from 28 days to
around 3 trillion years, which feels safely outside of the realms of
possibility.
The cost of this is slightly more generated code in some commonly
executed paths, but this is pretty minimal:
I have been unable to measure any change in performance of the LMbench
lat_ctx or lat_proc tests resulting from the 64b ASIDs on either
32r2el_defconfig+interAptiv or 32r6el_defconfig+I6500 systems.
Signed-off-by: Paul Burton <paul.burton@mips.com> Suggested-by: James Hogan <jhogan@kernel.org>
References: https://lore.kernel.org/linux-mips/80B78A8B8FEE6145A87579E8435D78C30205D5F3@fzex.ruijie.com.cn/
References: https://lore.kernel.org/linux-mips/1488684260-18867-1-git-send-email-jiwei.sun@windriver.com/ Cc: Jiwei Sun <jiwei.sun@windriver.com> Cc: Yu Huabing <yhb@ruijie.com.cn> Cc: stable@vger.kernel.org # 2.6.12+ Cc: linux-mips@vger.kernel.org
For most OCTEON SoCs there is a repeated and redundant register definition
for almost every hardware register, although the register bit fields
would not differ from other SoCs. Since the driver code should use only
one definition for simplicity, these other fields are just redundant
and can be deleted.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Cc: linux-mips@vger.kernel.org
Paul Burton [Mon, 26 Nov 2018 18:58:40 +0000 (18:58 +0000)]
MIPS: Hardcode cpu_has_mips* where target ISA allows
In the same vein as commit 93e01942a6eb ("MIPS: Hardcode cpu_has_* where
known at compile time due to ISA"), we can use our knowledge of the ISA
being targeted by the kernel build to make cpu_has_mips* macros
compile-time constant in some cases. This allows the compiler greater
opportunity to optimize out code which will never execute.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21245/ Cc: linux-mips@linux-mips.org
Paul Burton [Mon, 26 Nov 2018 18:47:33 +0000 (18:47 +0000)]
MIPS: MT: Remove norps command line parameter
The "norps" kernel command line parameter has apparently been deprecated
ever since it was added to the kernel back in 2006 - all it does is
print a message telling the user to use something else.
Remove the long dead "norps" parameter.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21244/ Cc: linux-mips@linux-mips.org
Paul Burton [Thu, 22 Nov 2018 03:47:57 +0000 (19:47 -0800)]
MIPS: Only include mmzone.h when CONFIG_NEED_MULTIPLE_NODES=y
MIPS' asm/mmzone.h includes the machine/platform mmzone.h
unconditionally, but since commit bb53fdf395ee ("MIPS: c-r4k: Add
r4k_blast_scache_node for Loongson-3") is included by asm/rk4cache.h for
all r4k-style configs regardless of CONFIG_NEED_MULTIPLE_NODES.
This is problematic when CONFIG_NEED_MULTIPLE_NODES=n because both the
loongson3 & ip27 mmzone.h headers unconditionally define the NODE_DATA
preprocessor macro which is aready defined by linux/mmzone.h, resulting
in the following build error:
In file included from ./arch/mips/include/asm/mmzone.h:10,
from ./arch/mips/include/asm/r4kcache.h:23,
from arch/mips/mm/c-r4k.c:33:
./arch/mips/include/asm/mach-loongson64/mmzone.h:48: error: "NODE_DATA" redefined [-Werror]
#define NODE_DATA(n) (&__node_data[(n)]->pglist)
In file included from ./include/linux/topology.h:32,
from ./include/linux/irq.h:19,
from ./include/asm-generic/hardirq.h:13,
from ./arch/mips/include/asm/hardirq.h:16,
from ./include/linux/hardirq.h:9,
from arch/mips/mm/c-r4k.c:11:
./include/linux/mmzone.h:907: note: this is the location of the previous definition
#define NODE_DATA(nid) (&contig_page_data)
Resolve this by only including the machine mmzone.h when
CONFIG_NEED_MULTIPLE_NODES=y, which also removes the need for the empty
mach-generic version of the header which we delete.
Signed-off-by: Paul Burton <paul.burton@mips.com> Fixes: bb53fdf395ee ("MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3")
Paul Burton [Wed, 21 Nov 2018 21:56:36 +0000 (21:56 +0000)]
MIPS: Enable dead code elimination
Select CONFIG_HAVE_LD_DEAD_CODE_DATA_ELIMINATION for MIPS, allowing the
user to enable dead code elimination. In order for this to work, ensure
that we keep the data bus exception table & the machine list by
annotating them with KEEP.
This shrinks both 32r2el_defconfig & 64r6el_defconfig builds by ~6%, as
shown by numbers from scripts/bloat-o-meter:
Paul Burton [Wed, 21 Nov 2018 00:58:31 +0000 (00:58 +0000)]
MIPS: Regenerate defconfigs
A couple of patches have come up recently to remove particular instances
of obsolete Kconfig symbols from defconfigs. Rather than doing this
piecemeal, simply regenerate them all.
Signed-off-by: Paul Burton <paul.burton@mips.com>
References: https://patchwork.linux-mips.org/patch/19635/
References: https://patchwork.linux-mips.org/patch/21156/
Patchwork: https://patchwork.linux-mips.org/patch/21184/ Cc: Anders Roxell <anders.roxell@linaro.org> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: linux-mips@linux-mips.org
Paul Burton [Tue, 20 Nov 2018 23:59:56 +0000 (23:59 +0000)]
MIPS: malta: Use img-ascii-lcd driver for LCD display
Remove the Malta display platform code in favour of probing the
img-ascii-lcd driver via device tree. This reduces the amount of
platform code & the img-ascii-lcd driver offers us advantages in terms
of code sharing with other boards & functionality such as changing the
displayed message via sysfs. Defconfigs are untouched because the driver
already defaults y on when CONFIG_MIPS_MALTA=y.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21182/ Cc: linux-mips@linux-mips.org
Paul Burton [Tue, 20 Nov 2018 20:41:05 +0000 (20:41 +0000)]
MIPS: ptrace: introduce NT_MIPS_MSA regset
The current methods for obtaining FP context via ptrace only provide
either 32 or 64 bits per data register. With MSA, where vector registers
are aliased with scalar FP data registers, those registers are 128 bits
wide. Thus a new mechanism is required for userland to access those
registers via ptrace. This patch introduces an NT_MIPS_MSA regset which
provides, in this order:
- The full 128 bits value of each vector register, in native
endianness saved as though elements are doubles. That is, the format
of each vector register is as would be obtained by saving it to
memory using an st.d instruction.
- The 32 bit scalar FP implementation register (FIR).
- The 32 bit scalar FP control & status register (FCSR).
- The 32 bit MSA implementation register (MSAIR).
- The 32 bit MSA control & status register (MSACSR).
The provision of the FIR & FCSR registers in addition to the MSA
equivalents allows scalar FP context to be retrieved as a subset of
the context available via this regset. Along with the MSA equivalents
they also nicely form the final 128 bit "register" of the regset.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21180/ Cc: linux-mips@linux-mips.org
Huacai Chen [Thu, 15 Nov 2018 07:53:56 +0000 (15:53 +0800)]
MIPS: Align kernel load address to 64KB
KEXEC needs the new kernel's load address to be aligned on a page
boundary (see sanity_check_segment_list()), but on MIPS the default
vmlinuz load address is only explicitly aligned to 16 bytes.
Since the largest PAGE_SIZE supported by MIPS kernels is 64KB, increase
the alignment calculated by calc_vmlinuz_load_addr to 64KB.
Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21131/ Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <james.hogan@mips.com> Cc: Steven J . Hill <Steven.Hill@cavium.com> Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: <stable@vger.kernel.org> # 2.6.36+
Huacai Chen [Thu, 15 Nov 2018 07:53:53 +0000 (15:53 +0800)]
MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3
For multi-node Loongson-3 (NUMA configuration), r4k_blast_scache() can
only flush Node-0's scache. So we add r4k_blast_scache_node() by using
(CAC_BASE | (node_id << NODE_ADDRSPACE_SHIFT)) instead of CKSEG0 as the
start address.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
[paul.burton@mips.com: Include asm/mmzone.h from asm/r4kcache.h for
nid_to_addrbase(). Add asm/mach-generic/mmzone.h
to allow inclusion for all platforms.] Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21129/ Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <james.hogan@mips.com> Cc: Steven J . Hill <Steven.Hill@cavium.com> Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: <stable@vger.kernel.org> # 3.15+
Hassan Naveed [Tue, 20 Nov 2018 00:49:37 +0000 (16:49 -0800)]
MIPS: Enable Undefined Behavior Sanitizer UBSAN
Select ARCH_HAS_UBSAN_SANITIZE_ALL in order to allow the user to
enable CONFIG_UBSAN_SANITIZE_ALL and instrument the entire kernel for
ubsan checks.
We exclude the VDSO from this because its build doesn't include the
__ubsan_handle_*() functions that the kernel proper defines in from
lib/ubsan.c, and the VDSO would have no sane way to report errors even
if it had definitions of these functions.
Signed-off-by: Hassan Naveed <hnaveed@wavecomp.com> Reviewed-by: Paul Burton <paul.burton@mips.com> Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21179/ Cc: <linux-mips@linux-mips.org>
This check might otherwise be useful to stop users from using a non-linux
compiler, but if you're doing that you are going to have a lot more
trouble anyway.
Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21149/ Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
MIPS: SiByte: Enable swiotlb for SWARM, LittleSur and BigSur
The Broadcom SiByte BCM1250, BCM1125, and BCM1125H SOCs have an onchip
DRAM controller that supports memory amounts of up to 16GiB, and due to
how the address decoder has been wired in the SOC any memory beyond 1GiB
is actually mapped starting from 4GiB physical up, that is beyond the
32-bit addressable limit[1]. Consequently if the maximum amount of
memory has been installed, then it will span up to 19GiB.
Many of the evaluation boards we support that are based on one of these
SOCs have their memory soldered and the amount present fits in the
32-bit address range. The BCM91250A SWARM board however has actual DIMM
slots and accepts, depending on the peripherals revision of the SOC, up
to 4GiB or 8GiB of memory in commercially available JEDEC modules[2].
I believe this is also the case with the BCM91250C2 LittleSur board.
This means that up to either 3GiB or 7GiB of memory requires 64-bit
addressing to access.
I believe the BCM91480B BigSur board, which has the BCM1480 SOC instead,
accepts at least as much memory, although I have no documentation or
actual hardware available to verify that.
Both systems have PCI slots installed for use by any PCI option boards,
including ones that only support 32-bit addressing (additionally the
32-bit PCI host bridge of the BCM1250, BCM1125, and BCM1125H SOCs limits
addressing to 32-bits), and there is no IOMMU available. Therefore for
PCI DMA to work in the presence of memory beyond enable swiotlb for the
affected systems.
All the other SOC onchip DMA devices use 40-bit addressing and therefore
can address the whole memory, so only enable swiotlb if PCI support and
support for DMA beyond 4GiB have been both enabled in the configuration
of the kernel.
The LittleSur board is marked for high memory support and therefore
clearly must provide a way to have enough memory installed for some to
be present outside the low 4GiB physical address range. With the memory
map of the BCM1250 SOC it has been built around it means over 1GiB of
actual DRAM, as only the first 1GiB is mapped in the low 4GiB physical
address range[1].
Complement commit cce335ae47e2 ("[MIPS] 64-bit Sibyte kernels need
DMA32.") then and also enable ZONE_DMA32 for LittleSur.
References:
[1] "BCM1250/BCM1125/BCM1125H User Manual", Revision 1250_1125-UM100-R,
Broadcom Corporation, 21 Oct 2002, Section 3: "System Overview",
"Memory Map", pp. 34-38
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Paul Burton <paul.burton@mips.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Patchwork: https://patchwork.linux-mips.org/patch/21107/ Fixes: cce335ae47e2 ("[MIPS] 64-bit Sibyte kernels need DMA32.") Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
The Broadcom SiByte BCM1250, BCM1125H and BCM1125 SOCs have an onchip
32-bit PCI host bridge, and the two former SOCs also have an onchip HT
host bridge. The HT host bridge, where present, appears in the PCI
configuration space as if it was a device on the 32-bit PCI bus behind
the PCI host bridge, however at the hardware level its signals are
routed separately, so these two devices are actually peer host bridges.
As documented[1] and observed in reality the 32-bit PCI host bridge does
not support 64-bit addressing as it does not support the Dual Address
Cycle (DAC) PCI command, and naturally, being 32-bit only, it has no
means to carry the high 32 address bits otherwise. However the DRAM
controller also included in the SOC supports memory amounts of up to
16GiB, and due to how the address decoder has been wired in the SOC any
memory beyond 1GiB is actually mapped starting from 4GiB physical up,
that is beyond the 32-bit addressable limit. Consequently if the
maximum amount of memory has been installed, then it will span up to
19GiB.
Contrariwise, the HT host bridge does support full 40-bit addressing
defined by the HyperTransport (formerly LDT) specification the bridge
adheres to, depending on the peripherals revision of the SOC[2] either
revision 0.17[3] or revision 1.03[4]. This allows addressing any and
all memory installed, and well beyond.
Set the bus mask then to limit DMA addressing to 32 bits for all the
devices down the 32-bit PCI host bridge, excluding however any devices
that are down the HT host bridge.
References:
[1] "BCM1250/BCM1125/BCM1125H User Manual", Revision 1250_1125-UM100-R,
Broadcom Corporation, 21 Oct 2002, Section 8: "PCI Bus and
HyperTransport Fabric", "Introduction", p. 190
Paul Burton [Thu, 8 Nov 2018 23:44:56 +0000 (23:44 +0000)]
lib/gcd: Remove use of CPU_NO_EFFICIENT_FFS macro
The CPU_NO_EFFICIENT_FFS pre-processor macro is no longer used, with all
architectures toggling the equivalent Kconfig symbol
CONFIG_CPU_NO_EFFICIENT_FFS instead. Remove our check for the unused
macro.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21046/ Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Paul Burton [Thu, 8 Nov 2018 23:44:55 +0000 (23:44 +0000)]
MIPS: Use Kconfig to select CPU_NO_EFFICIENT_FFS
Select CONFIG_CPU_NO_EFFICIENT_FFS via Kconfig when the kernel is
configured for a pre-MIPS32r1 CPU, rather than defining its equivalent
in asm/cpu-features.h based upon overrides of cpu_has_mips* macros.
The latter only works if a platform has an cpu-feature-overrides.h
header which defines cpu_has_mips* macros, which are not generally
needed. There are many cases where we know that the target ISA for a
kernel build is MIPS32r1 or later & thus includes the CLZ instruction,
without requiring any overrides from the platform. Using Kconfig allows
us to take those into account, and more naturally make a decision about
instruction support using information about the target ISA.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21045/ Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Paul Burton [Sat, 10 Nov 2018 00:12:06 +0000 (00:12 +0000)]
MIPS: Boston: Disable EG20T prefetch
The Intel EG20T Platform Controller Hub used on the MIPS Boston
development board supports prefetching memory to optimize DMA transfers.
Unfortunately for unknown reasons this doesn't work well with some MIPS
CPUs such as the P6600, particularly when using an I/O Coherence Unit
(IOCU) to provide cache-coherent DMA. In these systems it is common for
DMA data to be lost, resulting in broken access to EG20T devices such as
the MMC or SATA controllers.
Support for a DT property to configure the prefetching was added a while
back by commit 549ce8f134bd ("misc: pch_phub: Read prefetch value from
device tree if passed") but we never added the DT snippet to make use of
it. Add that now in order to disable the prefetching & fix DMA on the
affected systems.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21068/ Cc: linux-mips@linux-mips.org
Paul Burton [Thu, 8 Nov 2018 20:14:38 +0000 (20:14 +0000)]
MIPS: Avoid using .set mips0 to restore ISA
We currently have 2 commonly used methods for switching ISA within
assembly code, then restoring the original ISA.
1) Using a pair of .set push & .set pop directives. For example:
.set push
.set mips32r2
<some_insn>
.set pop
2) Using .set mips0 to restore the ISA originally specified on the
command line. For example:
.set mips32r2
<some_insn>
.set mips0
Unfortunately method 2 does not work with nanoMIPS toolchains, where the
assembler rejects the .set mips0 directive like so:
Error: cannot change ISA from nanoMIPS to mips0
In preparation for supporting nanoMIPS builds, switch all instances of
method 2 in generic non-platform-specific code to use push & pop as in
method 1 instead. The .set push & .set pop is arguably cleaner anyway,
and if nothing else it's good to consistently use one method.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21037/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:11 +0000 (23:14 +0000)]
MIPS: Allow FP support to be disabled
Allow the user to configure the kernel to omit support for floating
point, by setting CONFIG_MIPS_FP_SUPPORT=n. In an attempt to avoid
problems for users who don't understand the impact of this, only expose
the option when CONFIG_EXPERT=y.
When CONFIG_MIPS_FP_SUPPORT=n all support for FPU hardware, FPU
emulation & FP context will be removed from the kernel. If a userland
program attempts to execute a floating point instruction it will receive
a SIGILL.
Setting CONFIG_MIPS_FP_SUPPORT=n shaves around 112KB from a
64r6el_defconfig build using GCC 8.1.0.
This also helps prepare us for supporting the nanoMIPS ISA, for which
floating point support has not been finalized.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21014/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:10 +0000 (23:14 +0000)]
MIPS: Remove struct task_struct fpu state when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point & so don't
need to preserve floating point context for tasks. Remove that context
from struct task_struct.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21013/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:10 +0000 (23:14 +0000)]
MIPS: Don't compile math-emu when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so
there's no point compiling in our FPU emulator. Avoid doing so,
providing stub versions of dsemul cleanup functions that are called from
signal & task handling code.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21012/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:09 +0000 (23:14 +0000)]
MIPS: Avoid FCSR sanitization when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so we
don't need to worry about floating point exceptions pending in the
Floating point Control & Status Register (FCSR) during switch_to(). Stub
out the __sanitize_fcr31() macro in this case.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21010/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:09 +0000 (23:14 +0000)]
MIPS: Avoid FP ELF checks when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so we can
avoid needless checks of ELF headers specifying the FP ABI or NaN
encoding to use. Deselect CONFIG_ARCH_BINFMT_ELF_STATE in this case to
avoid the need for our arch_elf_pt_proc() & arch_check_elf() functions,
and stub out the mips_set_personality_nan() & mips_set_personality_fp()
functions such that SET_PERSONALITY() doesn't need to worry about any of
this.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21011/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:08 +0000 (23:14 +0000)]
MIPS: signal: Remove FP context support when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so
there's no need to save & restore floating point context around signals.
This prepares us for the removal of FP context from struct task_struct
later.
Since MSA context is a superset of FP context support for it similarly
needs to be removed when MSA/FP support is disabled.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21009/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:07 +0000 (23:14 +0000)]
MIPS: ptrace: Remove FP support when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so remove
the related ptrace support. Besides removing code which should not be
needed, this prepares us for the removal of FPU state in struct
task_struct which this code requires.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21008/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:07 +0000 (23:14 +0000)]
MIPS: unaligned: Remove FP & MSA code when unsupported
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so remove
support for floating point instructions from emulate_load_store_insn() &
emulate_load_store_microMIPS(). This code should not be needed & relies
upon access to FPU state in struct task_struct which will later be
removed.
Similarly & for the same reasons, when CONFIG_CPU_HAS_MSA=n remove
support for MSA instructions. Since MSA support depends upon FP support
this is implied when CONFIG_MIPS_FP_SUPPORT=n.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21020/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:06 +0000 (23:14 +0000)]
MIPS: branch: Remove FP branch handling when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so remove
the floating point branch support from __compute_return_epc_for_insn() &
__mm_isBranchInstr(). This code should never be needed & more
importantly relies upon FPU state in struct task_struct which will later
be removed.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21017/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:05 +0000 (23:14 +0000)]
MIPS: traps: Never enable FPU when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so we'll
never need to enable the FPU. Avoid doing so on a Co-Processor Unusable
exception (do_cpu), and remove the Floating Point Exception handler
(do_fpe) which should never be executed when the FPU is disabled.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21007/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:04 +0000 (23:14 +0000)]
MIPS: Stub asm/fpu.h functions
Provide stub versions of functions in asm/fpu.h when
CONFIG_MIPS_FP_SUPPORT=n. Two approaches are taken to the functions
provided:
- Functions which can safely be called when FP is not enabled provide
stubs which return an error where appropriate or are simple no-ops.
- Functions which should only ever be called in cases where
cpu_has_fpu is true or the FPU was successfully enabled are declared
extern & annotated with __compiletime_error() to detect cases in
which they are called incorrectly.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21006/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:03 +0000 (23:14 +0000)]
MIPS: Hardcode cpu_has_fpu=0 when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so
there's no point in detecting presence of an FPU. Hardcode
cpu_has_fpu=0 such that we optimize out code that makes use of the FPU.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21005/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:02 +0000 (23:14 +0000)]
MIPS: Introduce CONFIG_MIPS_FP_SUPPORT
Introduce a Kconfig variable that will indicate whether to include
support for floating point in the kernel. For now this is always
enabled, and will be made configurable in a later patch.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21016/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:00 +0000 (23:14 +0000)]
MIPS: Drop forward declarations of sigcontext in asm/fpu.h
asm/fpu.h contains forward declarations of struct sigcontext & struct
sigcontext32 which appear to have been unused since commit 137f6f3e284e
("MIPS: Cleanup signal code initialization"). Remove the dead code.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21015/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:14:00 +0000 (23:14 +0000)]
MIPS: Ensure emulated FP sets PF_USED_MATH
Emulated floating point instructions don't ensure that the PF_USED_MATH
flag is set for the task. This results in a couple of inconsistencies:
- ptrace will return the default initial state of FP registers rather
than the values actually stored in struct thread_struct, hiding
state that has been updated by emulated floating point instructions.
- If a task migrates to a CPU with an FPU after having emulated
floating point instructions then its floating point register state
will be reset to the default ~0 bit pattern, losing state from the
emulated instructions.
Fix this by calling init_fp_ctx() from fpu_emulator_cop1Handler() to
consistently initialize FP state if it was previously uninitialized,
setting the PF_USED_MATH flag in the process.
All callers of fpu_emulator_cop1Handler() either call lose_fpu(1) before
it in order to save any live FPU registers to struct thread_struct, or
in the case of do_cpu() already know that the task does not own an FPU
so lose_fpu(1) would be a no-op. Since we know that saving FP context
will be unnecessary in the case where FP context was just initialized we
move this call into fpu_emulator_cop1Handler() too, providing
consistency & avoiding needless duplication.
Calls to own_fpu(1) are common after return from
fpu_emulator_cop1Handler() too, but this would not be a no-op in the
do_cpu() case so these are left as-is. A potential future improvement
could be to have fpu_emulator_cop1Handler() restore FPU state
automatically only if it saved it, though this may not be optimal if
some callers are better off without their current calls to own_fpu(1).
One potential example of this could be mipsr2_decoder() which as-is
could end up saving & restoring FP context repeatedly & unnecessarily if
emulating multiple FP instructions.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21003/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:13:59 +0000 (23:13 +0000)]
MIPS: Simplify FP context initialization
MIPS has up until now had 3 different ways for a task's floating point
context to be initialized:
- If the task's first use of FP involves it gaining ownership of an
FPU then _init_fpu() is used to initialize the FPU's registers such
that they all contain ~0, and the FPU registers will be stored to
struct thread_info later (eg. when context switching).
- If the task first uses FP on a CPU without an associated FPU then
fpu_emulator_init_fpu() initializes the task's floating point
register state in struct thread_info such that all floating point
register contain the bit pattern 0x7ff800007ff80000, different to
the _init_fpu() behaviour.
- If a task's floating point context is first accessed via ptrace then
init_fp_ctx() initializes the floating point register state in
struct thread_info to ~0, giving equivalent state to _init_fpu().
The _init_fpu() path has 2 separate implementations - one for r2k/r3k
style systems & one for r4k style systems. The _init_fpu() path also
requires that we be careful to clear & restore the value of the
Config5.FRE bit on modern systems in order to avoid inadvertently
triggering floating point exceptions.
None of this code is in a performance critical hot path - it runs only
the first time a task uses floating point. As such it doesn't seem to
warrant the complications of maintaining the _init_fpu() path.
Remove _init_fpu() & fpu_emulator_init_fpu(), instead using
init_fp_ctx() consistently to initialize floating point register state
in struct thread_info. Upon a task's first use of floating point this
will typically mean that we initialize state in memory & then load it
into FPU registers using _restore_fp() just as we would on a context
switch. For other paths such as __compute_return_epc_for_insn() or
mipsr2_decoder() this results in a significant simplification of the
work to be done.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21002/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:13:58 +0000 (23:13 +0000)]
MIPS: BCM5xxx: Remove dead init_fpu code
The BMIPS5xxx core_init function contains a call to an init_fpu function
inside an #ifdef whose condition never evaluates true. Remove the dead
code. FPU initialization happens later, primarily when a userland
program attempts to use it.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21018/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:13:58 +0000 (23:13 +0000)]
MIPS: Hide CONFIG_MIPS_O32_FP64_SUPPORT prompt for >= MIPSr6
From MIPSr6 onwards FP64 support is mandatory, and so
CONFIG_MIPS_O32_FP64_SUPPORT is always selected for configurations which
support O32 binaries. Hide the useless unchangeable prompt in these
cases.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21019/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:19:41 +0000 (23:19 +0000)]
MIPS: Hardcode cpu_has_mmips=1 for microMIPS kernels
If we built the kernel targeting the microMIPS ISA then the very fact
that the kernel is running implies that the CPU supports microMIPS. Thus
we can hardcode cpu_has_mmips to 1 allowing the compiler greater scope
for optimisation due to the compile-time constant.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21022/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:05:46 +0000 (23:05 +0000)]
MIPS: Simplify GCC_OFF_SMALL_ASM definition
The GCC_OFF_SMALL_ASM macro defines the constraint to use for
instructions needing "small offsets", typically the LL or SC
instructions. Historically these had 16 bit offsets, but microMIPS &
MIPS32/MIPS64r6 onwards reduced the width of the offset field.
GCC 4.9 & higher supports a ZC constraint which matches the offset
requirements of the LL & SC instructions. Where supported we can use
the ZC constraint regardless of ISA, and it will handle the requirements
of the ISA correctly. As such we require 3 cases:
- GCC 4.9 & higher can use ZC.
- GCC older than 4.9 must use the older R constraint, which does not
take into account microMIPS or MIPSr6.
- microMIPS builds therefore require GCC 4.9 or higher. MIPSr6 support
was only introduced in newer compilers anyway so it can be ignored
here.
The current code complicates this a little by specifically having MIPSr6
bypass the GCC version check, and using the R constraint for pre-MIPSr6
builds even if the compiler supports ZC which would be equivalent.
Simplify this such that the code straightforwardly implements the 3
cases outlined above.
For non-GCC compilers we presume that ZC is safe to use. In practice the
only non-GCC compiler of interest is clang and it has supported the ZC
constraint since version 3.7.0. It seems safe enough to presume that
nobody will expect to built a working kernel using a clang version older
than that, and if they do then they'll have bigger problems. As such we
don't check the clang version number & just presume ZC is usable when
the compiler is not GCC.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20999/ Cc: linux-mips@linux-mips.org
Paul Burton [Wed, 7 Nov 2018 23:05:07 +0000 (23:05 +0000)]
MIPS: Remove GCC_IMM_ASM & GCC_REG_ACCUM macros
asm/compiler.h defined GCC_IMM_ASM & GCC_REG_ACCUM macros, both of which
are defined differently for GCC pre-3.4 or GCC 3.4 & higher. We only
support building with GCC 4.6 & higher since commit cafa0010cd51 ("Raise
the minimum required gcc version to 4.6"), which makes the pre-3.4
definition dead code.
Rather than leave the macro definitions around, inline the GCC 3.4 &
higher definitions into the single file that uses them & remove the
macros entirely.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21000/ Cc: linux-mips@linux-mips.org
This supports computers based on the R4000SC processor:
* DECstation 5000/150 and DECsystem 5000/150,
* Personal DECstation 5000/50, Personal DECsystem 5000/50,
and computers based on the R4400SC processor:
* DECstation 5000/260 and DECsystem 5000/260,
* DECsystem 5900/260,
in the 64-bit mode.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20986/ Cc: Ralf Baechle <ralf@linux-mips.org>
This supports computers based on the R4000SC processor:
* DECstation 5000/150 and DECsystem 5000/150,
* Personal DECstation 5000/50, Personal DECsystem 5000/50,
and computers based on the R4400SC processor:
* DECstation 5000/260 and DECsystem 5000/260,
* DECsystem 5900/260,
in the 32-bit mode.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20985/ Cc: Ralf Baechle <ralf@linux-mips.org>
MIPS: DEC: Update R3k DECstation defconfig for Y2018
Regenerate the R3k DECstation defconfig, in particular including more
relevant drivers.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20984/ Cc: Ralf Baechle <ralf@linux-mips.org>
Hassan Naveed [Tue, 30 Oct 2018 01:27:41 +0000 (18:27 -0700)]
MIPS: Enable IOREMAP_PROT config option for MIPS cpus
Allows the users of ptrace to access memory mapped by the ptraced process
using the same cache coherency attributes as the original process.
For example while using gdb with ioremap_prot() incorporated, both gdb and
the process being traced will have same cache coherency attributes.
Linus Torvalds [Sun, 4 Nov 2018 22:46:04 +0000 (14:46 -0800)]
Merge tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifs
Pull UBIFS updates from Richard Weinberger:
- Full filesystem authentication feature, UBIFS is now able to have the
whole filesystem structure authenticated plus user data encrypted and
authenticated.
- Minor cleanups
* tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifs: (26 commits)
ubifs: Remove unneeded semicolon
Documentation: ubifs: Add authentication whitepaper
ubifs: Enable authentication support
ubifs: Do not update inode size in-place in authenticated mode
ubifs: Add hashes and HMACs to default filesystem
ubifs: authentication: Authenticate super block node
ubifs: Create hash for default LPT
ubfis: authentication: Authenticate master node
ubifs: authentication: Authenticate LPT
ubifs: Authenticate replayed journal
ubifs: Add auth nodes to garbage collector journal head
ubifs: Add authentication nodes to journal
ubifs: authentication: Add hashes to index nodes
ubifs: Add hashes to the tree node cache
ubifs: Create functions to embed a HMAC in a node
ubifs: Add helper functions for authentication support
ubifs: Add separate functions to init/crc a node
ubifs: Format changes for authentication support
ubifs: Store read superblock node
ubifs: Drop write_node
...
Linus Torvalds [Sun, 4 Nov 2018 16:20:09 +0000 (08:20 -0800)]
Merge tag 'nfs-for-4.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
Bugfix:
- Fix build issues on architectures that don't provide 64-bit cmpxchg
Cleanups:
- Fix a spelling mistake"
* tag 'nfs-for-4.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: fix spelling mistake, EACCESS -> EACCES
SUNRPC: Use atomic(64)_t for seq_send(64)
Linus Torvalds [Sun, 4 Nov 2018 16:12:44 +0000 (08:12 -0800)]
Merge tag 'ntb-4.20' of git://github.com/jonmason/ntb
Pull NTB updates from Jon Mason:
"Fairly minor changes and bug fixes:
NTB IDT thermal changes and hook into hwmon, ntb_netdev clean-up of
private struct, and a few bug fixes"
* tag 'ntb-4.20' of git://github.com/jonmason/ntb:
ntb: idt: Alter the driver info comments
ntb: idt: Discard temperature sensor IRQ handler
ntb: idt: Add basic hwmon sysfs interface
ntb: idt: Alter temperature read method
ntb_netdev: Simplify remove with client device drvdata
NTB: transport: Try harder to alloc an aligned MW buffer
ntb: ntb_transport: Mark expected switch fall-throughs
ntb: idt: Set PCIe bus address to BARLIMITx
NTB: ntb_hw_idt: replace IS_ERR_OR_NULL with regular NULL checks
ntb: intel: fix return value for ndev_vec_mask()
ntb_netdev: fix sleep time mismatch
Linus Torvalds [Sun, 4 Nov 2018 01:37:09 +0000 (18:37 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"A memory (under-)allocation fix and a comment fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/topology: Fix off by one bug
sched/rt: Update comment in pick_next_task_rt()
Linus Torvalds [Sun, 4 Nov 2018 01:25:17 +0000 (18:25 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"A number of fixes and some late updates:
- make in_compat_syscall() behavior on x86-32 similar to other
platforms, this touches a number of generic files but is not
intended to impact non-x86 platforms.
- objtool fixes
- PAT preemption fix
- paravirt fixes/cleanups
- cpufeatures updates for new instructions
- earlyprintk quirk
- make microcode version in sysfs world-readable (it is already
world-readable in procfs)
- minor cleanups and fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
compat: Cleanup in_compat_syscall() callers
x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT
objtool: Support GCC 9 cold subfunction naming scheme
x86/numa_emulation: Fix uniform-split numa emulation
x86/paravirt: Remove unused _paravirt_ident_32
x86/mm/pat: Disable preemption around __flush_tlb_all()
x86/paravirt: Remove GPL from pv_ops export
x86/traps: Use format string with panic() call
x86: Clean up 'sizeof x' => 'sizeof(x)'
x86/cpufeatures: Enumerate MOVDIR64B instruction
x86/cpufeatures: Enumerate MOVDIRI instruction
x86/earlyprintk: Add a force option for pciserial device
objtool: Support per-function rodata sections
x86/microcode: Make revision and processor flags world-readable
Linus Torvalds [Sun, 4 Nov 2018 01:13:43 +0000 (18:13 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates and fixes from Ingo Molnar:
"These are almost all tooling updates: 'perf top', 'perf trace' and
'perf script' fixes and updates, an UAPI header sync with the merge
window versions, license marker updates, much improved Sparc support
from David Miller, and a number of fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
perf intel-pt/bts: Calculate cpumode for synthesized samples
perf intel-pt: Insert callchain context into synthesized callchains
perf tools: Don't clone maps from parent when synthesizing forks
perf top: Start display thread earlier
tools headers uapi: Update linux/if_link.h header copy
tools headers uapi: Update linux/netlink.h header copy
tools headers: Sync the various kvm.h header copies
tools include uapi: Update linux/mmap.h copy
perf trace beauty: Use the mmap flags table generated from headers
perf beauty: Wire up the mmap flags table generator to the Makefile
perf beauty: Add a generator for MAP_ mmap's flag constants
tools include uapi: Update asound.h copy
tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
tools include uapi: Update linux/fs.h copy
perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
perf cs-etm: Correct CPU mode for samples
perf unwind: Take pgoff into account when reporting elf to libdwfl
perf top: Do not use overwrite mode by default
perf top: Allow disabling the overwrite mode
perf trace: Beautify mount's first pathname arg
...
Linus Torvalds [Sun, 4 Nov 2018 01:12:09 +0000 (18:12 -0700)]
Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
"An irqchip driver fix and a memory (over-)allocation fix"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-mvebu-sei: Fix a NULL vs IS_ERR() bug in probe function
irq/matrix: Fix memory overallocation
Linus Torvalds [Sat, 3 Nov 2018 17:55:23 +0000 (10:55 -0700)]
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull more arm64 updates from Catalin Marinas:
- fix W+X page (mark RO) allocated by the arm64 kprobes code
- Makefile fix for .i files in out of tree modules
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: kprobe: make page to RO mode when allocate it
arm64: kdump: fix small typo
arm64: makefile fix build of .i file in external module case