Paul Burton [Fri, 19 Aug 2016 17:13:34 +0000 (18:13 +0100)]
MIPS: c-r4k: Treat I6400 dcache as though physically indexed
The L1 data cache in I6400 CPUs is indexed by physical address bits if
an entry for the address is present in the DTLB early enough in the
pipelined execution of a memory access instruction. If an entry is not
present then it's indexed by virtual address bits, but hardware will
check in a later pipeline stage when a DTLB entry has been created
whether the virtual address bits used match the physical address bits,
and if not will transparently restart the memory access instruction.
This means that although it isn't always physically indexed, it appears
so to software & we can treat the I6400 L1 data cache as being
physically indexed in order to avoid considering aliasing.
Paul Burton [Fri, 2 Sep 2016 14:18:21 +0000 (15:18 +0100)]
MIPS: Netlogic: Fix assembler warning from smpboot.S
The netlogic platform can be built for either MIPS32 or MIPS64, and when
built for MIPS32 (as by nlm_xlr_defconfig) the use of the dla
pseudo-instruction leads to warnings such as the following from recent
versions of the GNU assembler:
arch/mips/netlogic/common/smpboot.S: Assembler messages:
arch/mips/netlogic/common/smpboot.S:62: Warning: dla used to load 32-bit register; recommend using la instead
arch/mips/netlogic/common/smpboot.S:63: Warning: dla used to load 32-bit register; recommend using la instead
Avoid these warnings by using the PTR_LA macro to make use of the
appropriate la or dla pseudo-instruction for the build.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: 66d29985fab8 ("MIPS: Netlogic: Merge some of XLR/XLP wakup code") Cc: James Hogan <james.hogan@imgtec.com> Cc: Jayachandran C <jchandra@broadcom.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14185/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 7 Nov 2016 11:14:16 +0000 (11:14 +0000)]
MIPS: Export {copy, clear}_page functions alongside their definitions
Now that EXPORT_SYMBOL can be used from assembly source, move the
EXPORT_SYMBOL invocations for the copy_page & clear_page functions to be
alongside their definitions.
With this change there are no longer any symbols exported from
mips_ksyms.c so remove the file.
Paul Burton [Mon, 7 Nov 2016 11:14:15 +0000 (11:14 +0000)]
MIPS: Export memcpy & memset functions alongside their definitions
Now that EXPORT_SYMBOL can be used from assembly source, move the
EXPORT_SYMBOL invocations for the memcpy & memset functions & variants
thereof to be alongside their definitions.
Paul Burton [Mon, 7 Nov 2016 11:14:14 +0000 (11:14 +0000)]
MIPS: Export string functions alongside their definitions
Now that EXPORT_SYMBOL can be used from assembly source, move the
EXPORT_SYMBOL invocations for the strlen*, strnlen* & strncpy* functions
to be alongside their definitions.
Paul Burton [Mon, 7 Nov 2016 11:14:13 +0000 (11:14 +0000)]
MIPS: Export csum functions alongside their definitions
Now that EXPORT_SYMBOL can be used from assembly source, move the
EXPORT_SYMBOL invocations for the csum_partial_* functions to be
alongside their definitions.
Paul Burton [Mon, 7 Nov 2016 11:14:10 +0000 (11:14 +0000)]
MIPS: Export _save_fp & _save_msa alongside their definitions
Now that EXPORT_SYMBOL can be used from assembly source, move the
EXPORT_SYMBOL invocations for _save_fp & _save_msa to be alongside their
definitions.
Paul Burton [Mon, 7 Nov 2016 11:14:09 +0000 (11:14 +0000)]
MIPS: End asm function prologue macros with .insn
When building a kernel targeting a microMIPS ISA, recent GNU linkers
will fail the link if they cannot determine that the target of a branch
or jump is microMIPS code, with errors such as the following:
mips-img-linux-gnu-ld: arch/mips/built-in.o: .text+0x542c:
Unsupported jump between ISA modes; consider recompiling with
interlinking enabled.
mips-img-linux-gnu-ld: final link failed: Bad value
or:
./arch/mips/include/asm/uaccess.h:1017: warning: JALX to a
non-word-aligned address
Placing anything other than an instruction at the start of a function
written in assembly appears to trigger such errors. In order to prepare
for allowing us to follow function prologue macros with an EXPORT_SYMBOL
invocation, end the prologue macros (LEAD, NESTED & FEXPORT) with a
.insn directive. This ensures that the start of the function is marked
as code, which always makes sense for functions & safely prevents us
from hitting the link errors described above.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Reviewed-by: Maciej W. Rozycki <macro@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14508/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 7 Nov 2016 11:14:08 +0000 (11:14 +0000)]
MIPS: tlbex: Clear ISA bit when writing to handle_tlb{l,m,s}
When generating TLB exception handling code we write to memory reserved
at the handle_tlbl, handle_tlbm & handle_tlbs symbols. Up until now the
ISA bit has always been clear simply because the assembly code reserving
the space for those functions places no instructions in them. In
preparation for marking all LEAF functions as containing code,
explicitly clear the ISA bit when calculating the addresses at which to
write TLB exception handling code.
Paul Burton [Fri, 23 Sep 2016 15:38:27 +0000 (16:38 +0100)]
OF: Prevent unaligned access in of_alias_scan()
When allocating a struct alias_prop, of_alias_scan() only requested that
it be aligned on a 4 byte boundary. The struct contains pointers which
leads to us attempting 64 bit writes on 64 bit systems, and if the CPU
doesn't support unaligned memory accesses then this causes problems -
for example on some MIPS64r2 CPUs including the "mips64r2-generic" QEMU
emulated CPU it will trigger an address error exception.
Fix this by requesting alignment for the struct alias_prop allocation
matching that which the compiler expects, using the __alignof__ keyword.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Grant Likely <grant.likely@secretlab.ca> Cc: Frank Rowand <frowand.list@gmail.com> Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14306/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: uprobes: Remove __weak attribute from arch_uprobe_copy_ixol.
Arch-specific implementation of arch_uprobe_copy_ixol is expected to
override the weak implementation in generic code.
As currently both implementations are marked as weak, it is up to the
linker to chose one. Remove the __weak attribute from MIPS code to make
sure the correct version is used.
John Crispin [Tue, 20 Dec 2016 18:12:46 +0000 (19:12 +0100)]
MIPS: ralink: Cosmetic change to prom_init().
Over the years the code has been changed various times leading to
argc/argv being defined in a different function to where we actually
use the variables. Clean this up by moving them to prom_init_cmdline().
John Crispin [Tue, 20 Dec 2016 18:12:43 +0000 (19:12 +0100)]
MIPS: ralink: Fix a typo in the pinmux setup.
There is a typo inside the pinmux setup code. The function is really
called utif and not util. This was recently discovered when people were
trying to make the UTIF interface work.
John Crispin [Tue, 20 Dec 2016 18:12:42 +0000 (19:12 +0100)]
MIPS: ralink: Add missing pinmux.
The mt7620 has a pin that can be used to generate an external reference
clock. The pinmux setup was missing the definition of said pin. This patch
adds it.
John Crispin [Tue, 20 Dec 2016 18:12:40 +0000 (19:12 +0100)]
MIPS: ralink: MT7621 does not set its SoC type.
The code does not set the SoC type properly. This went unnoticed until now
as the SoC does not share any of the driver code with the other SoCs, until
we made the mmc driver work.
Justin Chen [Thu, 8 Dec 2016 01:16:26 +0000 (17:16 -0800)]
MIPS: Add cacheinfo support
Add cacheinfo support for MIPS architectures.
Use information from the cpuinfo_mips struct to populate the
cacheinfo struct. This allows an architecture agnostic approach,
however this also means if cache information is not properly
populated within the cpuinfo_mips struct, there is nothing
we can do. (I.E. c-r3k.c)
MIPS: kexec: Do not reserve invalid crashkernel memory on boot
Do not reserve memory for the crashkernel if the commandline argument
points to a wrong location. This can happen if the location is specified
wrong or if the same commandline is reused when starting the crashkernel
- in the latter case the reserved memory would point to the location
from which the crashkernel is executing.
When a memory offset is specified through the commandline, add the
memory in range PHYS_OFFSET:Y as reserved memory area.
Otherwise the bootmem allocator is initialised with low page equal to
min_low_pfn = PHYS_OFFSET, and in free_all_bootmem will process pages
starting from min_low_pfn instead of PFN(Y).
If the DTB is located in the target memory area for the relocated kernel
it needs to be relocated as well before kernel relocation takes place.
After copying the DTB use the new plat_fdt_relocated() API from the
relocated kernel to ensure the relocated kernel updates any information
that it may have cached about the location of the DTB.
plat_fdt_relocated is declared as a weak symbol so that platforms that
do not require it do not need to implement the method.
MIPS: platform: Allow for DTB to be moved during kernel relocation
Add plat_fdt_relocated(void*) API to allow the kernel relocation code to
update platform's information about the DTB location if the DTB had to
be moved due to being placed in a location used by the relocated kernel.
MIPS: Use early_init_fdt_reserve_self to protect DTB location
early_init_fdt_reserve_self is used to tell the boot memory allocator
that a memory is occupied by the DTB, so add it in the MIPS init code to
ensure information about the DTB is added to the boot memory array.
MIPS: init: Ensure bootmem does not corrupt reserved memory
Current init code initialises bootmem allocator with all of the low
memory that it assumes is available, but does not check for reserved
memory block, which can lead to corruption of data that may be stored
there.
Move bootmem's allocation map to a location that does not cross any
reserved regions
MIPS: init: Ensure reserved memory regions are not added to bootmem
Memories managed through boot_mem_map are generally expected to define
non-crossing areas. However, if part of a larger memory block is marked
as reserved, it would still be added to bootmem allocator as an
available block and could end up being overwritten by the allocator.
Prevent this by explicitly marking the memory as reserved it if exists
in the range used by bootmem allocator.
MIPS does not currently define ELF_CORE_COPY_REGS macros and as a result
the generic implementation is used. The generic version attempts to do
directly map (struct pt_regs) into (elf_gregset_t), which isn't correct
for MIPS platforms and also triggers a BUG() at runtime in
include/linux/elfcore.h:16 (BUG_ON(sizeof(*elfregs) != sizeof(*regs)))
[ralf@linux-mips.org: Add semicolons to the macro definitions as I do not
apply https://patchwork.linux-mips.org/patch/14588/ for now.]
MIPS: Move register dump routines out of ptrace code
Current register dump methods for MIPS are implemented inside ptrace
methods, but there will be other uses in the kernel for them, so keep
them separately in process.c and use those definitions for ptrace
instead.
SMP_DUMP has been added as a new IPI signal when kexec support was added
for Cavium Octeon CPUs ('commit 7aa1c8f47e7e ("MIPS: kdump: Add support")'.
However, the new signal doesn't appear to ever have a proper handler
added (octeon_message_functions[] array has an empty handler for it),
and generic IPI handlers now trigger a BUG() on unhandled signal.
As the method is unused remove it completely and replace its only
invocation with a smp_call_function().
[ralf@linux-mips.org: Renumber SMP_ASK_C0COUNT to avoid numbering gaps.]
Matt Redfearn [Thu, 24 Nov 2016 17:32:45 +0000 (17:32 +0000)]
MIPS: Add support for ARCH_MMAP_RND_{COMPAT_}BITS
arch_mmap_rnd() uses hard-coded limits of 16MB for the randomisation
of mmap within 32bit processes and 256MB in 64bit processes. Since v4.4
other arches support tuning this value in /proc/sys/vm/mmap_rnd_bits.
Add support for this to MIPS.
Set the minimum(default) number of bits randomisation for 32bit to 8 -
which with 4k pagesize is unchanged from the current 16MB total
randomness. The minimum(default) for 64bit is 12bits, again with 4k
pagesize this is the same as the current 256MB.
This patch is necessary for MIPS32 to pass the Android CTS tests, with
the number of random bits set to 15.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Daniel Cashman <dcashman@android.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mips@linux-mips.org Cc: kernel-hardening@lists.openwall.com Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14617/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Hauke Mehrtens [Wed, 30 Nov 2016 22:58:08 +0000 (23:58 +0100)]
MIPS: Lantiq: Activate more drivers in default configuration
This activates the following functionalities:
* SMP support (used on xRX200)
* PCI support
* NAND driver
* PHY driver
* UART
* Watchdog
* USB 2.0 controller
These driver are driving different IP cores found on the supported SoCs.
Tobias Wolf [Wed, 23 Nov 2016 09:40:07 +0000 (10:40 +0100)]
of: Add check to of_scan_flat_dt() before accessing initial_boot_params
An empty __dtb_start to __dtb_end section might result in
initial_boot_params being null for arch/mips/ralink. This showed that the
boot process hangs indefinitely in of_scan_flat_dt().
Signed-off-by: Tobias Wolf <dev-NTEO@vplace.de> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14605/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Tobias Wolf [Tue, 13 Dec 2016 10:46:41 +0000 (11:46 +0100)]
ralink: Introduce fw_passed_dtb to arch/mips/ralink
This patch adds fw_passed_dtb to arch/mips/ralink to support
CONFIG_MIPS_RAW_APPENDED_DTB. Furthermore it adds a check that __dtb_start is
not the same address as __dtb_end.
Signed-off-by: Tobias Wolf <dev-NTEO@vplace.de> Acked-by: John Crispin <john@phrozen.org> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14662/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 17 Oct 2016 14:34:37 +0000 (15:34 +0100)]
MIPS: Allow pre-r6 emulation on SMP MIPSr6 kernels
There's no reason for the pre-r6 instruction emulation code to be
limited to uniprocessor kernels. We already emulate atomic memory access
instructions in a way that works for SMP systems, and nothing else
should be affected. Remove the artificial limitation, allowing pre-r6
instruction emulation to be used with SMP kernels.
Paul Burton [Mon, 17 Oct 2016 14:34:36 +0000 (15:34 +0100)]
MIPS: Cleanup LLBit handling in switch_to
Commit 7c151d3d5d7a ("MIPS: Make use of the ERETNC instruction on MIPS
R6") began clearing LLBit during context switches, but did so on all
systems where it is writable for unclear reasons & did so from a macro
with "software_ll_bit" in its name, which is intended to operate on the
ll_bit variable used by ll/sc emulation for old CPUs.
We do now need to clear LLBit on MIPSr6 systems where we'll use eretnc
to return to userland, but we don't need to do so on MIPSr5 systems with
a writable LLBit.
Move the clear to its own appropriately named macro, do it only for
MIPSr6 systems & comment about why.
Paul Burton [Mon, 17 Oct 2016 14:34:35 +0000 (15:34 +0100)]
MIPS: Remove r2_emul_return from struct thread_info
The r2_emul_return field in struct thread_info was used in order to take
an alternate codepath when returning to userland, which (besides not
implementing certain features) effectively used the eretnc instruction
in place of eret. The difference is that eretnc doesn't clear LLBit, and
therefore doesn't cause a linked load & store sequence to fail due to
emulation like eret would.
The reason eret would usually be used to clear LLBit is so that after
context switching we ensure that a load performed by one task doesn't
influence another task. However commit 7c151d3d5d7a ("MIPS: Make use of
the ERETNC instruction on MIPS R6") which introduced the r2_emul_return
field and conditional use of eretnc also for some reason began
explicitly clearing LLBit during context switches - despite retaining
the use of eret for everything but returns from the pre-r6 instruction
emulation code.
As LLBit is cleared upon context switches anyway, simplify this by using
eretnc unconditionally for MIPSr6 kernels. This allows us to remove the
4 byte r2_emul_return boolean from struct thread_info, simplify the
return to user code in entry.S and avoid the overhead of tracking &
checking state which we don't need.
Rahul Bedarkar [Fri, 14 Oct 2016 05:55:55 +0000 (11:25 +0530)]
MIPS: DTS: img: add device tree for Marduk board
Add support for Imagination Technologies' Marduk board which is based
on Pistachio SoC. It is also known as Creator Ci40. Marduk is legacy
name and will be there for decades.
Documentation for this board can be found on
https://docs.creatordev.io/ci40/
This patch adds initial support for board with following peripherals:
* PWM based heartbeat LED
* GPIO based buttons
* SPI NOR flash on SPI1
* UART0 and UART1
* SD card
* Ethernet
* USB
* PWM
* ADC
* I2C
Signed-off-by: Rahul Bedarkar <rahul.bedarkar@imgtec.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: James Hartley <james.hartley@imgtec.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-mips@linux-mips.org Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14394/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 17 Oct 2016 15:01:07 +0000 (16:01 +0100)]
MIPS: traps: Ensure L1 & L2 ECC checking match for CM3 systems
On systems with CM3, we must ensure that the L1 & L2 ECC enables are set
to the same value. This is presumed by the hardware & cache corruption
can occur when it is not the case. Support enabling & disabling the L2
ECC checking on CM3 systems where this is controlled via a GCR, and
ensure that it matches the state of L1 ECC checking. Remove I6400 from
the switch statement it will no longer hit, and which was incorrect
since the L2 ECC enable bit isn't in the CP0 ErrCtl register.
Florian Fainelli [Mon, 31 Oct 2016 21:17:36 +0000 (14:17 -0700)]
MIPS: BMIPS: Migrate interrupts during bmips_cpu_disable
While we properly disabled the per-CPU timer interrupt, we also need to
make sure that all interrupts that can possibly have this CPU in their
smp_affinity mask also have a chance to see this interrupt migrated to a
CPU not being taken offline.
Matt Redfearn [Fri, 4 Nov 2016 09:28:58 +0000 (09:28 +0000)]
MIPS: SMP-CPS: Don't BUG if a CPU fails to start
If there is no online CPU within a core which could receive the IPI to
start another VP in that core, a BUG() is triggered. Instead print a
warning and gracefully handle the failure such that the system remains
usable, albeit without the requested secondary CPU.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Qais Yousef <qsyousef@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14504/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn [Fri, 4 Nov 2016 09:28:56 +0000 (09:28 +0000)]
MIPS: SMP: Use a completion event to signal CPU up
If a secondary CPU failed to start, for any reason, the CPU requesting
the secondary to start would get stuck in the loop waiting for the
secondary to be present in the cpu_callin_map.
Rather than that, use a completion event to signal that the secondary
CPU has started and is waiting to synchronise counters.
Since the CPU presence will no longer be marked in cpu_callin_map,
remove the redundant test from arch_cpu_idle_dead().
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Qais Yousef <qsyousef@gmail.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14502/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 7 Nov 2016 11:30:41 +0000 (11:30 +0000)]
MIPS: Netlogic: Exclude netlogic,xlp-pic code from XLR builds
Code in arch/mips/netlogic/common/irq.c which handles the XLP PIC fails
to build in XLR configurations due to cpu_is_xlp9xx not being defined,
leading to the following build failure:
arch/mips/netlogic/common/irq.c: In function ‘xlp_of_pic_init’:
arch/mips/netlogic/common/irq.c:298:2: error: implicit declaration
of function ‘cpu_is_xlp9xx’ [-Werror=implicit-function-declaration]
if (cpu_is_xlp9xx()) {
^
Although the code was conditional upon CONFIG_OF which is indirectly
selected by CONFIG_NLM_XLP_BOARD but not CONFIG_NLM_XLR_BOARD, the
failing XLR with CONFIG_OF configuration can be configured manually or
by randconfig.
Fix the build failure by making the affected XLP PIC code conditional
upon CONFIG_CPU_XLP which is used to guard the inclusion of
asm/netlogic/xlp-hal/xlp.h that provides the required cpu_is_xlp9xx
function.
[ralf@linux-mips.org: Fixed up as per Jayachandran's suggestion.]
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Jayachandran C <jchandra@broadcom.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14524/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn [Thu, 10 Nov 2016 10:02:13 +0000 (10:02 +0000)]
MIPS: Use Makefile.postlink to insert relocations into vmlinux
When relocatable support for MIPS was merged, there was no support for
an architecture to add a postlink step for vmlinux. This meant that only
invoking a target within the boot directory, such as uImage, caused the
relocations to be inserted into vmlinux. Building just the vmlinux
target would result in a relocatable kernel with no relocation
information present.
Commit fbe6e37dab97 ("kbuild: add arch specific post-link Makefile")
recified this situation, so MIPS can now define a postlink step to add
relocation information into vmlinux, and remove the additional steps
tacked onto boot targets.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Tested-by: Steven J. Hill <steven.hill@cavium.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14554/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 7 Nov 2016 15:07:07 +0000 (15:07 +0000)]
MIPS: Handle microMIPS jumps in the same way as MIPS32/MIPS64 jumps
is_jump_ins() checks for plain jump ("j") instructions since commit e7438c4b893e ("MIPS: Fix sibling call handling in get_frame_info") but
that commit didn't make the same change to the microMIPS code, leaving
it inconsistent with the MIPS32/MIPS64 code. Handle the microMIPS
encoding of the jump instruction too such that it behaves consistently.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: e7438c4b893e ("MIPS: Fix sibling call handling in get_frame_info") Cc: Tony Wu <tung7970@gmail.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # v3.10+
Patchwork: https://patchwork.linux-mips.org/patch/14533/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 7 Nov 2016 15:07:06 +0000 (15:07 +0000)]
MIPS: Calculate microMIPS ra properly when unwinding the stack
get_frame_info() calculates the offset of the return address within a
stack frame simply by dividing a the bottom 16 bits of the instruction,
treated as a signed integer, by the size of a long. Whilst this works
for MIPS32 & MIPS64 ISAs where the sw or sd instructions are used, it's
incorrect for microMIPS where encodings differ. The result is that we
typically completely fail to unwind the stack on microMIPS.
Fix this by adjusting is_ra_save_ins() to calculate the return address
offset, and take into account the various different encodings there in
the same place as we consider whether an instruction is storing the
ra/$31 register.
With this we are now able to unwind the stack for kernels targetting the
microMIPS ISA, for example we can produce:
Paul Burton [Mon, 7 Nov 2016 15:07:05 +0000 (15:07 +0000)]
MIPS: Fix is_jump_ins() handling of 16b microMIPS instructions
is_jump_ins() checks 16b instruction fields without verifying that the
instruction is indeed 16b, as is done by is_ra_save_ins() &
is_sp_move_ins(). Add the appropriate check.
Paul Burton [Mon, 7 Nov 2016 15:07:04 +0000 (15:07 +0000)]
MIPS: Fix get_frame_info() handling of microMIPS function size
get_frame_info() is meant to iterate over up to the first 128
instructions within a function, but for microMIPS kernels it will not
reach that many instructions unless the function is 512 bytes long since
we calculate the maximum number of instructions to check by dividing the
function length by the 4 byte size of a union mips_instruction. In
microMIPS kernels this won't do since instructions are variable length.
Fix this by instead checking whether the pointer to the current
instruction has reached the end of the function, and use max_insns as a
simple constant to check the number of iterations against.
Paul Burton [Mon, 7 Nov 2016 15:07:03 +0000 (15:07 +0000)]
MIPS: Prevent unaligned accesses during stack unwinding
During stack unwinding we call a number of functions to determine what
type of instruction we're looking at. The union mips_instruction pointer
provided to them may be pointing at a 2 byte, but not 4 byte, aligned
address & we thus cannot directly access the 4 byte wide members of the
union mips_instruction. To avoid this is_ra_save_ins() copies the
required half-words of the microMIPS instruction to a correctly aligned
union mips_instruction on the stack, which it can then access safely.
The is_jump_ins() & is_sp_move_ins() functions do not correctly perform
this temporary copy, and instead attempt to directly dereference 4 byte
fields which may be misaligned and lead to an address exception.
Fix this by copying the instruction halfwords to a temporary union
mips_instruction in get_frame_info() such that we can provide a 4 byte
aligned union mips_instruction to the is_*_ins() functions and they do
not need to deal with misalignment themselves.
Paul Burton [Mon, 7 Nov 2016 15:07:02 +0000 (15:07 +0000)]
MIPS: Clear ISA bit correctly in get_frame_info()
get_frame_info() can be called in microMIPS kernels with the ISA bit
already clear. For example this happens when unwind_stack_by_address()
is called because we begin with a PC that has the ISA bit set & subtract
the (odd) offset from the preceding symbol (which does not have the ISA
bit set). Since get_frame_info() unconditionally subtracts 1 from the PC
in microMIPS kernels it incorrectly misaligns the address it then
attempts to access code at, leading to an address error exception.
Fix this by using msk_isa16_mode() to clear the ISA bit, which allows
get_frame_info() to function regardless of whether it is provided with a
PC that has the ISA bit set or not.
Paul Burton [Mon, 17 Oct 2016 14:56:21 +0000 (15:56 +0100)]
MIPS: Use generic asm/unaligned.h
The MIPS-specific asm/unaligned.h provides nothing that the generic
version doesn't - it simply uses MIPS-specific endianness macros in
place of generic ones & lacks support for
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS. Remove it & switch to using the
generic version to remove duplication.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14412/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Mon, 7 Nov 2016 11:52:19 +0000 (11:52 +0000)]
MIPS: Ensure bss section ends on a long-aligned address
When clearing the .bss section in kernel_entry we do so using LONG_S
instructions, and branch whilst the current write address doesn't equal
the end of the .bss section minus the size of a long integer. The .bss
section always begins at a long-aligned address and we always increment
the write pointer by the size of a long integer - we therefore rely upon
the .bss section ending at a long-aligned address. If this is not the
case then the long-aligned write address can never be equal to the
non-long-aligned end address & we will continue to increment past the
end of the .bss section, attempting to zero the rest of memory.
Despite this requirement that .bss end at a long-aligned address we pass
0 as the end alignment requirement to the BSS_SECTION macro and thus
don't guarantee any particular alignment, allowing us to hit the error
condition described above.
Fix this by instead passing 8 bytes as the end alignment argument to
the BSS_SECTION macro, ensuring that the end of the .bss section is
always at least long-aligned.
Steven J. Hill [Fri, 9 Dec 2016 08:36:22 +0000 (02:36 -0600)]
MIPS: Relocatable: Provide plat_post_relocation hook
This hook provides the platform the chance to perform any required
setup before the boot processor switches to the relocated kernel.
The relocated kernel has been copied and fixed up ready for execution
at this point. Secondary CPUs may wish to switch to it early. There
is also the opportunity for the platform to abort jumping to the
relocated kernel if there is anything wrong with the chosen offset.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Signed-off-by: Steven J. Hill <Steven.Hill@cavium.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14651/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Steven J. Hill [Tue, 13 Dec 2016 20:25:37 +0000 (14:25 -0600)]
MIPS: Octeon: Enable KASLR
This patch enables KASLR for Octeon systems. The SMP startup code is
such that the secondaries monitor the volatile variable
'octeon_processor_relocated_kernel_entry' for any non-zero value.
The 'plat_post_relocation hook' is used to set that value to the
kernel entry point of the relocated kernel. The secondary CPUs will
then jusmp to the new kernel, perform their initialization again
and begin waiting for the boot CPU to start them via the relocated
loop 'octeon_spin_wait_boot'. Inspired by Steven's code from Cavium.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Signed-off-by: Steven J. Hill <steven.hill@cavium.com> Acked-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14669/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Steven J. Hill [Tue, 22 Nov 2016 19:44:10 +0000 (13:44 -0600)]
MIPS: Octeon: Add fw_init_cmdline() for Cavium platforms.
Add platform-specific kernel command line processing for Octeon.
Signed-off-by: Steven J. Hill <steven.hill@cavium.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14599/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn [Mon, 19 Dec 2016 14:21:00 +0000 (14:21 +0000)]
MIPS: Select HAVE_IRQ_EXIT_ON_IRQ_STACK
Since do_IRQ is now invoked on a separate IRQ stack, we select
HAVE_IRQ_EXIT_ON_IRQ_STACK so that softirq's may be invoked directly
from irq_exit(), rather than requiring do_softirq_own_stack.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Acked-by: Jason A. Donenfeld <jason@zx2c4.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14744/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn [Mon, 19 Dec 2016 14:20:59 +0000 (14:20 +0000)]
MIPS: Switch to the irq_stack in interrupts
When enterring interrupt context via handle_int or except_vec_vi, switch
to the irq_stack of the current CPU if it is not already in use.
The current stack pointer is masked with the thread size and compared to
the base or the irq stack. If it does not match then the stack pointer
is set to the top of that stack, otherwise this is a nested irq being
handled on the irq stack so the stack pointer should be left as it was.
The in-use stack pointer is placed in the callee saved register s1. It
will be saved to the stack when plat_irq_dispatch is invoked and can be
restored once control returns here.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Acked-by: Jason A. Donenfeld <jason@zx2c4.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14743/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn [Mon, 19 Dec 2016 14:20:58 +0000 (14:20 +0000)]
MIPS: Only change $28 to thread_info if coming from user mode
The SAVE_SOME macro is used to save the execution context on all
exceptions.
If an exception occurs while executing user code, the stack is switched
to the kernel's stack for the current task, and register $28 is switched
to point to the current_thread_info, which is at the bottom of the stack
region.
If the exception occurs while executing kernel code, the stack is left,
and this change ensures that register $28 is not updated. This is the
correct behaviour when the kernel can be executing on the separate irq
stack, because the thread_info will not be at the base of it.
With this change, register $28 is only switched to it's kernel
conventional usage of the currrent thread info pointer at the point at
which execution enters kernel space. Doing it on every exception was
redundant, but OK without an IRQ stack, but will be erroneous once that
is introduced.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Acked-by: Jason A. Donenfeld <jason@zx2c4.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14742/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn [Mon, 19 Dec 2016 14:20:57 +0000 (14:20 +0000)]
MIPS: Stack unwinding while on IRQ stack
Within unwind stack, check if the stack pointer being unwound is within
the CPU's irq_stack and if so use that page rather than the task's stack
page.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Acked-by: Jason A. Donenfeld <jason@zx2c4.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Adam Buchbinder <adam.buchbinder@gmail.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14741/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Ralf Baechle [Thu, 15 Dec 2016 11:39:22 +0000 (12:39 +0100)]
MIPS: IP22: Fix build error due to binutils 2.25 uselessnes.
Fix the following build error with binutils 2.25.
CC arch/mips/mm/sc-ip22.o
{standard input}: Assembler messages:
{standard input}:132: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:159: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:200: Error: number (0x9000000080000000) larger than 32 bits
scripts/Makefile.build:293: recipe for target 'arch/mips/mm/sc-ip22.o' failed
make[1]: *** [arch/mips/mm/sc-ip22.o] Error 1
MIPS has used .set mips3 to temporarily switch the assembler to 64 bit
mode in 64 bit kernels virtually forever. Binutils 2.25 broke this
behavious partially by happily accepting 64 bit instructions in .set mips3
mode but puking on 64 bit constants when generating 32 bit ELF. Binutils
2.26 restored the old behaviour again.
Fix build with binutils 2.25 by open coding the offending
dli $1, 0x9000000080000000
as
li $1, 0x9000
dsll $1, $1, 48
which is ugly be the only thing that will build on all binutils vintages.
Paul Bolle [Fri, 25 Nov 2016 12:36:18 +0000 (13:36 +0100)]
MIPS: Zboot: Don't use $(LINUXINCLUDE) twice
The make variables KBUILD_CFLAGS and KBUILD_AFLAGS both contain
$(LINUXINCLUDE). But the build already picks up $(LINUXINCLUDE) from
scripts/Makefile.lib. The net effect is that the (long) list of include
directories is used twice.
This is harmless but pointless. So stop using $(LINUXINCLUDE) twice.
- Convert from printk() to pr_*(),
- Add missing continuations, to fix user-visible breakage,
- Drop superfluous casts (u64 has been unsigned long long on all
architectures for many years).
On rbtx4927, this restores the kernel output like:
uzImage.bin is vmlinuz.bin wrapped in a legacy U-Boot image. Since
the extraction code is inside the image, it does not depend on the
boot loader to extract the kernel.
Signed-off-by: Maarten ter Huurne <maarten@treewalker.org> Cc: Alban Bedel <albeu@free.fr> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14473/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Linus Torvalds [Sun, 1 Jan 2017 20:27:05 +0000 (12:27 -0800)]
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull DAX updates from Dan Williams:
"The completion of Jan's DAX work for 4.10.
As I mentioned in the libnvdimm-for-4.10 pull request, these are some
final fixes for the DAX dirty-cacheline-tracking invalidation work
that was merged through the -mm, ext4, and xfs trees in -rc1. These
patches were prepared prior to the merge window, but we waited for
4.10-rc1 to have a stable merge base after all the prerequisites were
merged.
Quoting Jan on the overall changes in these patches:
"So I'd like all these 6 patches to go for rc2. The first three
patches fix invalidation of exceptional DAX entries (a bug which
is there for a long time) - without these patches data loss can
occur on power failure even though user called fsync(2). The other
three patches change locking of DAX faults so that ->iomap_begin()
is called in a more relaxed locking context and we are safe to
start a transaction there for ext4"
These have received a build success notification from the kbuild
robot, and pass the latest libnvdimm unit tests. There have not been
any -next releases since -rc1, so they have not appeared there"
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
ext4: Simplify DAX fault path
dax: Call ->iomap_begin without entry lock during dax fault
dax: Finish fault completely when loading holes
dax: Avoid page invalidation races and unnecessary radix tree traversals
mm: Invalidate DAX radix tree entries only if appropriate
ext2: Return BH_New buffers for zeroed blocks
Linus Torvalds [Fri, 30 Dec 2016 17:32:26 +0000 (09:32 -0800)]
Merge tag 'docs-4.10-rc1-fix' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet:
"Two small fixes:
- A merge error on my part broke the DocBook build. I've
requisitioned one of tglx's frozen sharks for appropriate
disciplinary action and resolved to be more careful about testing
the DocBook stuff as long as it's still around.
- Fix an error in unaligned-memory-access.txt"
* tag 'docs-4.10-rc1-fix' of git://git.lwn.net/linux:
Documentation/unaligned-memory-access.txt: fix incorrect comparison operator
docs: Fix build failure
Olof Johansson [Thu, 29 Dec 2016 22:16:07 +0000 (14:16 -0800)]
mm/filemap: fix parameters to test_bit()
mm/filemap.c: In function 'clear_bit_unlock_is_negative_byte':
mm/filemap.c:933:9: error: too few arguments to function 'test_bit'
return test_bit(PG_waiters);
^~~~~~~~
Fixes: b91e1302ad9b ('mm: optimize PageWaiters bit use for unlock_page()') Signed-off-by: Olof Johansson <olof@lixom.net> Brown-paper-bag-by: Linus Torvalds <dummy@duh.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Tue, 27 Dec 2016 19:40:38 +0000 (11:40 -0800)]
mm: optimize PageWaiters bit use for unlock_page()
In commit 62906027091f ("mm: add PageWaiters indicating tasks are
waiting for a page bit") Nick Piggin made our page locking no longer
unconditionally touch the hashed page waitqueue, which not only helps
performance in general, but is particularly helpful on NUMA machines
where the hashed wait queues can bounce around a lot.
However, the "clear lock bit atomically and then test the waiters bit"
sequence turns out to be much more expensive than it needs to be,
because you get a nasty stall when trying to access the same word that
just got updated atomically.
On architectures where locking is done with LL/SC, this would be trivial
to fix with a new primitive that clears one bit and tests another
atomically, but that ends up not working on x86, where the only atomic
operations that return the result end up being cmpxchg and xadd. The
atomic bit operations return the old value of the same bit we changed,
not the value of an unrelated bit.
On x86, we could put the lock bit in the high bit of the byte, and use
"xadd" with that bit (where the overflow ends up not touching other
bits), and look at the other bits of the result. However, an even
simpler model is to just use a regular atomic "and" to clear the lock
bit, and then the sign bit in eflags will indicate the resulting state
of the unrelated bit #7.
So by moving the PageWaiters bit up to bit #7, we can atomically clear
the lock bit and test the waiters bit on x86 too. And architectures
with LL/SC (which is all the usual RISC suspects), the particular bit
doesn't matter, so they are fine with this approach too.
This avoids the extra access to the same atomic word, and thus avoids
the costly stall at page unlock time.
The only downside is that the interface ends up being a bit odd and
specialized: clear a bit in a byte, and test the sign bit. Nick doesn't
love the resulting name of the new primitive, but I'd rather make the
name be descriptive and very clear about the limitation imposed by
trying to work across all relevant architectures than make it be some
generic thing that doesn't make the odd semantics explicit.
So this introduces the new architecture primitive
clear_bit_unlock_is_negative_byte();
and adds the trivial implementation for x86. We have a generic
non-optimized fallback (that just does a "clear_bit()"+"test_bit(7)"
combination) which can be overridden by any architecture that can do
better. According to Nick, Power has the same hickup x86 has, for
example, but some other architectures may not even care.
All these optimizations mean that my page locking stress-test (which is
just executing a lot of small short-lived shell scripts: "make test" in
the git source tree) no longer makes our page locking look horribly bad.
Before all these optimizations, just the unlock_page() costs were just
over 3% of all CPU overhead on "make test". After this, it's down to
0.66%, so just a quarter of the cost it used to be.
(The difference on NUMA is bigger, but there this micro-optimization is
likely less noticeable, since the big issue on NUMA was not the accesses
to 'struct page', but the waitqueue accesses that were already removed
by Nick's earlier commit).
Acked-by: Nick Piggin <npiggin@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Bob Peterson <rpeterso@redhat.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / karo-tx-linux.git / log