Current ARC SDP boards cannot reliably handle 1Gbit
Ethernet connections due to limitations in hardware.
To make sure networking is stable on the board we're
limiting phy to 100 Mbit.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Makes it easier to handle init vs core cleanly, though the change is
fairly invasive across random architectures.
It simplifies the rbtree code immediately, however, while keeping the
core data together in the same cachline (now iff the rbtree code is
enabled).
Acked-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Fixes STAR 9000953410: "perf callgraph profiling causing RCU stalls"
| perf record -g -c 15000 -e cycles /sbin/hackbench
|
| INFO: rcu_preempt self-detected stall on CPU
| 1: (1 GPs behind) idle=609/140000000000002/0 softirq=2914/2915 fqs=603
| Task dump for CPU 1:
in-kernel dwarf unwinder has a fast binary lookup and a fallback linear
search (which iterates thru each of ~11K entries) thus takes 2 orders of
magnitude longer (~3 million cycles vs. 2000). Routines written in hand
assembler lack dwarf info (as we don't support assembler CFI pseudo-ops
yet) fail the unwinder binary lookup, hit linear search, failing
nevertheless in the end.
However the linear search is pointless as binary lookup tables are created
from it in first place. It is impossible to have binary lookup fail while
succeed the linear search. It is pure waste of cycles thus removed by
this patch.
This manifested as RCU stalls / NMI watchdog splat when running
hackbench under perf with callgraph profiling. The triggering condition
was perf counter overflowing in routine lacking dwarf info (like memset)
leading to patheic 3 million cycle unwinder slow path and by the time it
returned new interrupts were already pending (Timer, IPI) and taken
rightaway. The original memset didn't make forward progress, system kept
accruing more interrupts and more unwinder delayes in a vicious feedback
loop, ultimately triggering the NMI diagnostic.
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
SYNC in __switch_to() is a historic relic and not needed at all.
- In UP context it is obviously useless, why would we want to stall
the core for all updates to stack memory of t0 to complete before
loading kernel mode callee registers from t1 stack's memory.
- In SMP, there could be potential race in which outgoing task could
be concurrently picked for running on a different core, thus writes
to stack here need to be visible before the reads from stack on
other core. Peter confirmed that generic schedular already has needed
barriers (by way of rq lock) so there is no need for additional arch
barrier.
This came up when Noam was trying to replace this SYNC with EZChip
specific hardware thread scheduling instruction for their platform
support.
Link: http://lkml.kernel.org/r/20151102092654.GM17308@twins.programming.kicks-ass.net
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Cc: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Although kernel doesn't support the multiple IRQ priority levels provided
by HS38x core intc yet, ensure that the default prio value is used
anyways by relevant code.
SLEEP insn needs to be provided the IRQ priority level which can
interrupt it. This needs to be the default level which maynot
necessarily be 0 as assumed by current code.
This change allows a kernel with ARCV2_IRQ_DEF_PRIO = 1 to boot fine.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
When building kernel with buildroot built toolchain, CROSS_COMPILE
currently needs adjustment even if minor. This is because the defconfigs
prefer "arc-linux-uclibc-" prefix from hand built (non buildroot) toolchain
while buildroot provides "arc-buildroot-linux-uclibc-"
To avoid this use the common "arc-linux-" prefix which is provided by
buildroot and has also been in hand built tools for quite some time.
Signed-off-by: sujayraaj <sujayraaj@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: updated changelog]
- A bunch of brown paper bag bugs (MAINTAINERS list email, SMP build failure)
- cpu_relax() now compiler barrier for UP as well
- Handling of userspace Bus Errors for ARCompact builds
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Merge tag 'arc-4.4-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
"Found a couple of brown paper bag bugs with the prev pull request
(including a SMP build breakage report from Guenter). Since these are
urgent I also decided to send over a bunch of other pending fixes
which could have otherwise waited an rc or two.
Summary:
- A bunch of brown paper bag bugs (MAINTAINERS list email, SMP build
failure)
- cpu_relax() now compiler barrier for UP as well
- handling of userspace Bus Errors for ARCompact builds"
* tag 'arc-4.4-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: Fix silly typo in MAINTAINERS file
ARC: cpu_relax() to be compiler barrier even for UP
ARC: use ASL assembler mnemonic
ARC: [arcompact] Handle bus error from userspace as Interrupt not exception
ARC: remove extraneous header include
ARCv2: lib: memcpy: use local symbols
cpu_relax() on ARC has been barrier only for SMP (and no-op for UP). Per
recent discussions, it is safer to make it a compiler barrier
unconditionally.
Link: http://lkml.kernel.org/r/53A7D3AA.9020100@synopsys.com
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARCompact and ARCv2 only have ASL, while binutils used to support LSL as
a alias mnemonic.
Newer binutils (upstream) don't want to do that so replace it.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Bus errors from userspace on ARCompact based cores are handled by core
as a high priority L2 interrupt but current code treated it as interrupt
Handling an interrupt like exception is certainly not going to go unnoticed.
(and it worked so far as we never saw a Bus error from userspace until
IPPK guys tested a DDR controller with ECC error detection etc hence
needed to explicitly trigger/handle such errors)
- So move mem_service exception handler from common code into ARCv2 code.
- In ARCompact code, define mem_service as L2 interrupt handler which
just drops down to pure kernel mode and goes of to enqueue SIGBUS
Reported-by: Nelson Pereira <npereira@synopsys.com>
Tested-by: Ana Martins <amartins@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
- DT binding doc consolidation moving similar bindings to common
locations. The majority of these are display related which were
scattered in video/, fb/, drm/, gpu/, and panel/ directories.
- Add new config option, CONFIG_OF_ALL_DTBS, to enable building all dtbs
in the tree for most arches with dts files (except powerpc for now).
- OF_IRQ=n fixes for user enabled CONFIG_OF.
- of_node_put ref counting fixes from Julia Lawall.
- Common DT binding for wakeup-source and deprecation of all similar
bindings.
- DT binding for PXA LCD controller.
- Allow ignoring failed PCI resource translations in order to ignore
64-bit addresses on non-LPAE 32-bit kernels.
- Support setting the NUMA node from DT instead of only from parent
device.
- Couple of earlycon DT parsing fixes for address and options.
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Merge tag 'devicetree-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull DeviceTree updates from Rob Herring:
"A fairly large (by DT standards) pull request this time with the
majority being some overdue moving DT binding docs around to
consolidate similar bindings.
- DT binding doc consolidation moving similar bindings to common
locations. The majority of these are display related which were
scattered in video/, fb/, drm/, gpu/, and panel/ directories.
- Add new config option, CONFIG_OF_ALL_DTBS, to enable building all
dtbs in the tree for most arches with dts files (except powerpc for
now).
- OF_IRQ=n fixes for user enabled CONFIG_OF.
- of_node_put ref counting fixes from Julia Lawall.
- Common DT binding for wakeup-source and deprecation of all similar
bindings.
- DT binding for PXA LCD controller.
- Allow ignoring failed PCI resource translations in order to ignore
64-bit addresses on non-LPAE 32-bit kernels.
- Support setting the NUMA node from DT instead of only from parent
device.
- Couple of earlycon DT parsing fixes for address and options"
* tag 'devicetree-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (45 commits)
MAINTAINERS: update DT binding doc locations
devicetree: add Sigma Designs vendor prefix
of: simplify arch_find_n_match_cpu_physical_id() function
Documentation: arm: Fixed typo in socfpga fpga mgr example
Documentation: devicetree: fix reference to legacy wakeup properties
Documentation: devicetree: standardize/consolidate on "wakeup-source" property
drivers: of: removing assignment of 0 to static variable
xtensa: enable building of all dtbs
mips: enable building of all dtbs
metag: enable building of all dtbs
metag: use common make variables for dtb builds
h8300: enable building of all dtbs
arm64: enable building of all dtbs
arm: enable building of all dtbs
arc: enable building of all dtbs
arc: use common make variables for dtb builds
of: add config option to enable building of all dtbs
of/fdt: fix error checking for earlycon address
of/overlay: add missing of_node_put
of/platform: add missing of_node_put
...
Pull locking changes from Ingo Molnar:
"The main changes in this cycle were:
- More gradual enhancements to atomic ops: new atomic*_read_ctrl()
ops, synchronize atomic_{read,set}() ordering requirements between
architectures, add atomic_long_t bitops. (Peter Zijlstra)
- Add _{relaxed|acquire|release}() variants for inc/dec atomics and
use them in various locking primitives: mutex, rtmutex, mcs, rwsem.
This enables weakly ordered architectures (such as arm64) to make
use of more locking related optimizations. (Davidlohr Bueso)
- Implement atomic[64]_{inc,dec}_relaxed() on ARM. (Will Deacon)
- Futex kernel data cache footprint micro-optimization. (Rasmus
Villemoes)
- pvqspinlock runtime overhead micro-optimization. (Waiman Long)
- misc smaller fixlets"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ARM, locking/atomics: Implement _relaxed variants of atomic[64]_{inc,dec}
locking/rwsem: Use acquire/release semantics
locking/mcs: Use acquire/release semantics
locking/rtmutex: Use acquire/release semantics
locking/mutex: Use acquire/release semantics
locking/asm-generic: Add _{relaxed|acquire|release}() variants for inc/dec atomics
atomic: Implement atomic_read_ctrl()
atomic, arch: Audit atomic_{read,set}()
atomic: Add atomic_long_t bitops
futex: Force hot variables into a single cache line
locking/pvqspinlock: Kick the PV CPU unconditionally when _Q_SLOW_VAL
locking/osq: Relax atomic semantics
locking/qrwlock: Rename ->lock to ->wait_lock
locking/Documentation/lockstat: Fix typo - lokcing -> locking
locking/atomics, cmpxchg: Privatize the inclusion of asm/cmpxchg.h
Some generic THP bits are touched - all ACKed by Kirill
- Platform framework updates to prepare for EZChip arrival (still in works)
- ARC Public Mailing list setup finally (linux-snps-arc@lists.infraded.org)
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Merge tag 'arc-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta:
- Support for new MM features in ARCv2 cores (THP, PAE40) Some generic
THP bits are touched - all ACKed by Kirill
- Platform framework updates to prepare for EZChip arrival (still in works)
- ARC Public Mailing list setup finally (linux-snps-arc@lists.infraded.org)
* tag 'arc-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (42 commits)
ARC: mm: PAE40 support
ARC: mm: PAE40: tlbex.S: Explicitify the size of pte_t
ARC: mm: PAE40: switch to using phys_addr_t for physical addresses
ARC: mm: HIGHMEM: populate high memory from DT
ARC: mm: HIGHMEM: kmap API implementation
ARC: mm: preps ahead of HIGHMEM support #2
ARC: mm: preps ahead of HIGHMEM support
ARC: mm: use generic macros _BITUL()/_AC()
ARC: mm: Improve Duplicate PD Fault handler
MAINTAINERS: Add public mailing list for ARC
ARC: Ensure DT mem base is same as what kernel is built with
ARC: boot: Non Master cpus only need to call EARLY_CPU_SETUP once
ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_smp()
ARC: smp: Introduce smp hook @init_irq_cpu called for all cores
ARC: smp: Rename platform hook @init_smp -> @init_cpu_smp
ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_early_smp()
ARC: smp: Introduce smp hook @init_early_smp for Master core
ARC: remove @init_time, @init_irq platform callbacks
ARC: smp: irqchip: handle IPI as percpu irq like timer
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes
...
This is the first working implementation of 40-bit physical address
extension on ARCv2.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
That way a single flip of phys_addr_t to 64 bit ensures all places
dealing with physical addresses get correct data
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Implement kmap* API for ARC.
This enables
- permanent kernel maps (pkmaps): :kmap() API
- fixmap : kmap_atomic()
We use a very simple/uniform approach for both (unlike some of the other
arches). So fixmap doesn't use the customary compile time address stuff.
The important semantic is sleep'ability (pkmap) vs. not (fixmap) which
the API guarantees.
Note that this patch only enables highmem for subsequent PAE40 support
as there is no real highmem for ARC in pure 32-bit paradigm as explained
below.
ARC has 2:2 address split of the 32-bit address space with lower half
being translated (virtual) while upper half unstranslated
(0x8000_0000 to 0xFFFF_FFFF). kernel itself is linked at base of
unstranslated space (i.e. 0x8000_0000 onwards), which is mapped to say
DDR 0x0 by external Bus Glue logic (outside the core). So kernel can
potentially access 1.75G worth of memory directly w/o need for highmem.
(the top 256M is taken by uncached peripheral space from 0xF000_0000 to
0xFFFF_FFFF)
In PAE40, hardware can address memory beyond 4G (0x1_0000_0000) while
the logical/virtual addresses remain 32-bits. Thus highmem is required
for kernel proper to be able to access these pages for it's own purposes
(user space is agnostic to this anyways).
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Before we plug in highmem support, some of code needs to be ready for it
- copy_user_highpage() needs to be using the kmap_atomic API
- mk_pte() can't assume page_address()
- do_page_fault() can't assume VMALLOC_END is end of kernel vaddr space
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
- Move the verbosity knob from .data to .bss by using inverted logic
- No need to readout PD1 descriptor
- clip the non pfn bits of PD0 to avoid clipping inside the loop
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
With prev fixes, all cores now start via common entry point @stext which
already calls EARLY_CPU_SETUP for all cores - so no need to invoke it
again
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
MCIP now registers it's own per cpu setup routine (for IPI IRQ request)
using smp_ops.init_irq_cpu().
So no need for platforms to do that. This now completely decouples
platforms from MCIP.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Note this is not part of platform owned static machine_desc,
but more of device owned plat_smp_ops (rather misnamed) which a IPI
provider or some such typically defines.
This will help us seperate out the IPI registration from platform
specific init_cpu_smp() into device specific init_irq_cpu()
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
MCIP now registers it's own probe callback with smp_ops.init_early_smp()
which is called by ARC common code, so no need for platforms to do that.
This decouples the platforms and MCIP and helps confine MCIP details
to it's own file.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This adds a platform agnostic early SMP init hook which is called on
Master core before calling setup_processor()
setup_arch()
smp_init_cpus()
smp_ops.init_early_smp()
...
setup_processor()
How this helps:
- Used for one time init of certain SMP centric IP blocks, before
calling setup_processor() which probes various bits of core,
possibly including this block
- Currently platforms need to call this IP block init from their
init routines, which doesn't make sense as this is specific to ARC
core and not platform and otherwise requires copy/paste in all
(and hence a possible point of failure)
e.g. MCIP init is called from 2 platforms currently (axs10x and sim)
which will go away once we have this.
This change only adds the hooks but they are empty for now. Next commit
will populate them and remove the explicit init calls from platforms.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
These are not in use for ARC platforms. Moreover DT mechanims exist to
probe them w/o explicit platform calls.
- clocksource drivers can use CLOCKSOURCE_OF_DECLARE()
- intc IRQCHIP_DECLARE() calls + cascading inside DT allows external
intc to be probed automatically
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The reason this was not done so far was lack of genuine IPI_IRQ for
ARC700, as we don't have a SMP version of core yet (which might change
soon thx to EZChip). Nevertheles to increase the build coverage, we
need to allow CONFIG_SMP for ARC700 and still be able to run it on a
UP platform (nsim or AXS101) with a UP Device Tree (SMP-on-UP)
The build itself requires some define for IPI_IRQ and even a dummy
value is fine since that code won't run anyways.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
For Run-on-reset, non masters need to spin wait. For Halt-on-reset they
can jump to entry point directly.
Also while at it, made reset vector handler as "the" entry point for
kernel including host debugger based boot (which uses the ELF header
entry point)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Enable building all dtb files when CONFIG_OF_ALL_DTBS is enabled. The dtbs
are not really dependent on a platform being enabled or any other kernel
config, so for testing coverage it is convenient to build all of the dtbs.
This builds all dts files in the tree, not just targets listed.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Use dtb-y and always make variables to build dtbs instead of explicit
dtbs rule. This is in preparation to support building all dtbs.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
DesignWare MMC Controller's transfer mode should be decided
at runtime instead of compile-time. So we remove this config
option and read dw_mmc's register to select DMA master.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
For non halt-on-reset case, all cores start of simultaneously in @stext.
Master core0 proceeds with kernel boot, while other spin-wait on
@wake_flag being set by master once it is ready. So NO hardware assist
is needed for master to "kick" the others.
This patch moves this soft implementation out of mcip.c (as there is no
hardware assist) into common smp.c
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This frees up some bits to hold more high level info such as PAE being
present, w/o increasing the size of already bloated cpuinfo struct
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This is done by improving the laddering logic !
Before:
if Exception
goto excep_or_pure_k_ret
if !Interrupt(L2)
goto l1_chk
else
INTERRUPT_EPILOGUE 2
l1_chk:
if !Interrupt(L1) (i.e. pure kernel mode)
goto excep_or_pure_k_ret
else
INTERRUPT_EPILOGUE 1
excep_or_pure_k_ret:
EXCEPTION_EPILOGUE
Now:
if !Interrupt(L1 or L2) (i.e. exception or pure kernel mode)
goto excep_or_pure_k_ret
; guaranteed to be an interrupt
if !Interrupt(L2)
goto l1_ret
else
INTERRUPT_EPILOGUE 2
; by virtue of above, no need to chk for L1 active
l1_ret:
INTERRUPT_EPILOGUE 1
excep_or_pure_k_ret:
EXCEPTION_EPILOGUE
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The requirement is to
- Reenable Exceptions (AE cleared)
- Reenable Interrupts (E1/E2 set)
We need to do wiggle these bits into ERSTATUS and call RTIE.
Prev version used the pre-exception STATUS32 as starting point for what
goes into ERSTATUS. This required explicit fixups of U/DE/L bits.
Instead, use the current (in-exception) STATUS32 as starting point.
Being in exception handler U/DE/L can be safely assumed to be correct.
Only AE/E1/E2 need to be fixed.
So the new implementation is slightly better
-Avoids read form memory
-Is 4 bytes smaller for the typical 1 level of intr configuration
-Depicts the semantics more clearly
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Historically this was done by ARC IDE driver, which is long gone.
IRQ core is pretty robust now and already checks if IRQs are enabled
in hard ISRs. Thus no point in checking this in arch code, for every
call of irq enabled.
Further if some driver does do that - let it bring down the system so we
notice/fix this sooner than covering up for sucker
This makes local_irq_enable() - for L1 only case atleast simple enough
so we can inline it.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Implement the TLB flush routine to evict a sepcific Super TLB entry,
vs. moving to a new ASID on every such flush.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
MMUv4 in HS38x cores supports Super Pages which are basis for Linux THP
support.
Normal and Super pages can co-exist (ofcourse not overlap) in TLB with a
new bit "SZ" in TLB page desciptor to distinguish between them.
Super Page size is configurable in hardware (4K to 16M), but fixed once
RTL builds.
The exact THP size a Linx configuration will support is a function of:
- MMU page size (typical 8K, RTL fixed)
- software page walker address split between PGD:PTE:PFN (typical
11:8:13, but can be changed with 1 line)
So for above default, THP size supported is 8K * 256 = 2M
Default Page Walker is 2 levels, PGD:PTE:PFN, which in THP regime
reduces to 1 level (as PTE is folded into PGD and canonically referred
to as PMD).
Thus thp PMD accessors are implemented in terms of PTE (just like sparc)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC is the only arch with unsigned long type (vs. struct page *).
Historically this was done to avoid the page_address() calls in various
arch hooks which need to get the virtual/logical address of the table.
Some arches alternately define it as pte_t *, and is as efficient as
unsigned long (generated code doesn't change)
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull strscpy string copy function implementation from Chris Metcalf.
Chris sent this during the merge window, but I waffled back and forth on
the pull request, which is why it's going in only now.
The new "strscpy()" function is definitely easier to use and more secure
than either strncpy() or strlcpy(), both of which are horrible nasty
interfaces that have serious and irredeemable problems.
strncpy() has a useless return value, and doesn't NUL-terminate an
overlong result. To make matters worse, it pads a short result with
zeroes, which is a performance disaster if you have big buffers.
strlcpy(), by contrast, is a mis-designed "fix" for strlcpy(), lacking
the insane NUL padding, but having a differently broken return value
which returns the original length of the source string. Which means
that it will read characters past the count from the source buffer, and
you have to trust the source to be properly terminated. It also makes
error handling fragile, since the test for overflow is unnecessarily
subtle.
strscpy() avoids both these problems, guaranteeing the NUL termination
(but not excessive padding) if the destination size wasn't zero, and
making the overflow condition very obvious by returning -E2BIG. It also
doesn't read past the size of the source, and can thus be used for
untrusted source data too.
So why did I waffle about this for so long?
Every time we introduce a new-and-improved interface, people start doing
these interminable series of trivial conversion patches.
And every time that happens, somebody does some silly mistake, and the
conversion patch to the improved interface actually makes things worse.
Because the patch is mindnumbing and trivial, nobody has the attention
span to look at it carefully, and it's usually done over large swatches
of source code which means that not every conversion gets tested.
So I'm pulling the strscpy() support because it *is* a better interface.
But I will refuse to pull mindless conversion patches. Use this in
places where it makes sense, but don't do trivial patches to fix things
that aren't actually known to be broken.
* 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
tile: use global strscpy() rather than private copy
string: provide strscpy()
Make asm/word-at-a-time.h available on all architectures
This patch makes sure that atomic_{read,set}() are at least
{READ,WRITE}_ONCE().
We already had the 'requirement' that atomic_read() should use
ACCESS_ONCE(), and most archs had this, but a few were lacking.
All are now converted to use READ_ONCE().
And, by a symmetry and general paranoia argument, upgrade atomic_set()
to use WRITE_ONCE().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: james.hogan@imgtec.com
Cc: linux-kernel@vger.kernel.org
Cc: oleg@redhat.com
Cc: will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.
Remove the argument.
Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Pull locking and atomic updates from Ingo Molnar:
"Main changes in this cycle are:
- Extend atomic primitives with coherent logic op primitives
(atomic_{or,and,xor}()) and deprecate the old partial APIs
(atomic_{set,clear}_mask())
The old ops were incoherent with incompatible signatures across
architectures and with incomplete support. Now every architecture
supports the primitives consistently (by Peter Zijlstra)
- Generic support for 'relaxed atomics':
- _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
- atomic_read_acquire()
- atomic_set_release()
This came out of porting qwrlock code to arm64 (by Will Deacon)
- Clean up the fragile static_key APIs that were causing repeat bugs,
by introducing a new one:
DEFINE_STATIC_KEY_TRUE(name);
DEFINE_STATIC_KEY_FALSE(name);
which define a key of different types with an initial true/false
value.
Then allow:
static_branch_likely()
static_branch_unlikely()
to take a key of either type and emit the right instruction for the
case. To be able to know the 'type' of the static key we encode it
in the jump entry (by Peter Zijlstra)
- Static key self-tests (by Jason Baron)
- qrwlock optimizations (by Waiman Long)
- small futex enhancements (by Davidlohr Bueso)
- ... and misc other changes"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
jump_label/x86: Work around asm build bug on older/backported GCCs
locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
locking/static_keys: Make verify_keys() static
jump label, locking/static_keys: Update docs
locking/static_keys: Provide a selftest
jump_label: Provide a self-test
s390/uaccess, locking/static_keys: employ static_branch_likely()
x86, tsc, locking/static_keys: Employ static_branch_likely()
locking/static_keys: Add selftest
locking/static_keys: Add a new static_key interface
locking/static_keys: Rework update logic
locking/static_keys: Add static_key_{en,dis}able() helpers
...
Pull irq updates from Thomas Gleixner:
"This updated pull request does not contain the last few GIC related
patches which were reported to cause a regression. There is a fix
available, but I let it breed for a couple of days first.
The irq departement provides:
- new infrastructure to support non PCI based MSI interrupts
- a couple of new irq chip drivers
- the usual pile of fixlets and updates to irq chip drivers
- preparatory changes for removal of the irq argument from interrupt
flow handlers
- preparatory changes to remove IRQF_VALID"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
irqchip/imx-gpcv2: IMX GPCv2 driver for wakeup sources
irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2
irqchip: Add documentation for the bcm2836 interrupt controller
irqchip/bcm2835: Add support for being used as a second level controller
irqchip/bcm2835: Refactor handle_IRQ() calls out of MAKE_HWIRQ
PCI: xilinx: Fix typo in function name
irqchip/gic: Ensure gic_cpu_if_up/down() programs correct GIC instance
irqchip/gic: Only allow the primary GIC to set the CPU map
PCI/MSI: pci-xgene-msi: Consolidate chained IRQ handler install/remove
unicore32/irq: Prepare puv3_gpio_handler for irq argument removal
tile/pci_gx: Prepare trio_handle_level_irq for irq argument removal
m68k/irq: Prepare irq handlers for irq argument removal
C6X/megamode-pic: Prepare megamod_irq_cascade for irq argument removal
blackfin: Prepare irq handlers for irq argument removal
arc/irq: Prepare idu_cascade_isr for irq argument removal
sparc/irq: Use access helper irq_data_get_affinity_mask()
sparc/irq: Use helper irq_data_get_irq_handler_data()
parisc/irq: Use access helper irq_data_get_affinity_mask()
mn10300/irq: Use access helper irq_data_get_affinity_mask()
irqchip/i8259: Prepare i8259_irq_dispatch for irq argument removal
...
With all features in place, the ARC HS pct block can now be effectively
allowed to be probed/used
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* split off pmu info into singleton and per-cpu bits
* setup PMU on all cores
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
In times of ARC 700 performance counters didn't have support of
interrupt an so for ARC we only had support of non-sampling events.
Put simply only "perf stat" was functional.
Now with ARC HS we have support of interrupts in performance counters
which this change introduces support of.
ARC performance counters act in the following way in regard of
interrupts generation.
[1] A counter counts starting from value set in PCT_COUNT register pair
[2] Once counter reaches value set in PCT_INT_CNT interrupt is raised
Basic setup look like this:
[1] PCT_COUNT = 0;
[2] PCT_INT_CNT = __limit_value__;
[3] Enable interrupts for that counter and let it run
[4] Let counter reach its limit
[5] Handle interrupt when it happens
Note that PCT HW block is build in CPU core and so ints interrupt
line (which is basically OR of all counters IRQs) is wired directly to
top-level IRQC. That means do de-assert PCT interrupt it's required to
reset IRQs from all counters that have reached their limit values.
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This generalization prepares for support of overflow interrupts.
Hardware event counters on ARC work that way:
Each counter counts from programmed start value (set in
ARC_REG_PCT_COUNT) to a limit value (set in ARC_REG_PCT_INT_CNT) and
once limit value is reached this timer generates an interrupt.
Even though this hardware implementation allows for more flexibility,
in Linux kernel we decided to mimic behavior of other architectures
this way:
[1] Set limit value as half of counter's max value (to allow counter to
run after reaching it limit, see below for more explanation):
---------->8-----------
arc_pmu->max_period = (1ULL << counter_size) / 2 - 1ULL;
---------->8-----------
[2] Set start value as "arc_pmu->max_period - sample_period" and then
count up to the limit
Our event counters don't stop on reaching max value (the one we set in
ARC_REG_PCT_INT_CNT) but continue to count until kernel explicitly
stops each of them.
And setting a limit as half of counter capacity is done to allow
capturing of additional events in between moment when interrupt was
triggered until we're actually processing PMU interrupts. That way
we're trying to be more precise.
For example if we count CPU cycles we keep track of cycles while
running through generic IRQ handling code:
[1] We set counter period as say 100_000 events of type "crun"
[2] Counter reaches that limit and raises its interrupt
[3] Once we get in PMU IRQ handler we read current counter value from
ARC_REG_PCT_SNAP ans see there something like 105_000.
If counters stop on reaching a limit value then we would miss
additional 5000 cycles.
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The number of counters in PCT can never be more than 32 (while
countable conditions could be 100+) for both ARCompact and ARCv2
And while at it update copyright dates.
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
When kernel's binary becomes large enough (32M and more) errors
may occur during the final linkage stage. It happens because
the build system uses short relocations for ARC by default.
This problem may be easily resolved by passing -mlong-calls
option to GCC to use long absolute jumps (j) instead of short
relative branchs (b).
But there are fragments of pure assembler code exist which use
branchs in inappropriate places and cause a linkage error because
of relocations overflow.
First of these fragments is .fixup insertion in futex.h and
unaligned.c. It inserts a code in the separate section (.fixup)
with branch instruction. It leads to the linkage error when
kernel becomes large.
Second of these fragments is calling scheduler's functions
(common kernel code) from entry.S of ARC's code. When kernel's
binary becomes large it may lead to the linkage error because
scheduler may occur far enough from ARC's code in the final
binary.
Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
W/o hardware assisted atomic r-m-w the best we can do is to disable
preemption.
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC doesn't need the runtime detection of futex cmpxchg op
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Callers of cmpxchg_futex_value_locked() in futex code expect bimodal
return value:
!0 (essentially -EFAULT as failure)
0 (success)
Before this patch, the success return value was old value of futex,
which could very well be non zero, causing caller to possibly take the
failure path erroneously.
Fix that by returning 0 for success
(This fix was done back in 2011 for all upstream arches, which ARC
obviously missed)
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The atomic ops on futex need to provide the full barrier just like
regular atomics in kernel.
Also remove pagefault_enable/disable in futex_atomic_cmpxchg_inatomic()
as core code already does that
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
In case of ARCv2 CPU there're could be following configurations
that affect cache handling for data exchanged with peripherals
via DMA:
[1] Only L1 cache exists
[2] Both L1 and L2 exist, but no IO coherency unit
[3] L1, L2 caches and IO coherency unit exist
Current implementation takes care of [1] and [2].
Moreover support of [2] is implemented with run-time check
for SLC existence which is not super optimal.
This patch introduces support of [3] and rework of DMA ops
usage. Instead of doing run-time check every time a particular
DMA op is executed we'll have 3 different implementations of
DMA ops and select appropriate one during init.
As for IOC support for it we need:
[a] Implement empty DMA ops because IOC takes care of cache
coherency with DMAed data
[b] Route dma_alloc_coherent() via dma_alloc_noncoherent()
This is required to make IOC work in first place and also
serves as optimization as LD/ST to coherent buffers can be
srviced from caches w/o going all the way to memory
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
[vgupta:
-Added some comments about IOC gains
-Marked dma ops as static,
-Massaged changelog a bit]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The increment of delay counter was 2 instructions:
Arithmatic Shfit Left (ASL) + set to 1 on overflow
This can be done in 1 using ROtate Left (ROL)
Suggested-by: Nigel Topham <ntopham@synopsys.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
KGDB fails to build after f51e2f1911 ("ARC: make sure instruction_pointer()
returns unsigned value")
The hack to force one specific reg to unsigned backfired. There's no
reason to keep the regs signed after all.
| CC arch/arc/kernel/kgdb.o
|../arch/arc/kernel/kgdb.c: In function 'kgdb_trap':
| ../arch/arc/kernel/kgdb.c:180:29: error: lvalue required as left operand of assignment
| instruction_pointer(regs) -= BREAK_INSTR_SIZE;
Reported-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
Fixes: f51e2f1911 ("ARC: make sure instruction_pointer() returns unsigned value")
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The previous commit for delayed retry of SCOND needs some fine tuning
for spin locks.
The backoff from delayed retry in conjunction with spin looping of lock
itself can potentially cause the delay counter to reach high values.
So to provide fairness to any lock operation, after a lock "seems"
available (i.e. just before first SCOND try0, reset the delay counter
back to starting value of 1
Essentially reset delay to 1 for a new spin-wait-loop-acquire cycle.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This is to workaround the llock/scond livelock
HS38x4 could get into a LLOCK/SCOND livelock in case of multiple overlapping
coherency transactions in the SCU. The exclusive line state keeps rotating
among contenting cores leading to a never ending cycle. So break the cycle
by deferring the retry of failed exclusive access (SCOND). The actual delay
needed is function of number of contending cores as well as the unrelated
coherency traffic from other cores. To keep the code simple, start off with
small delay of 1 which would suffice most cases and in case of contention
double the delay. Eventually the delay is sufficient such that the coherency
pipeline is drained, thus a subsequent exclusive access would succeed.
Link: http://lkml.kernel.org/r/1438612568-28265-1-git-send-email-vgupta@synopsys.com
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
With LLOCK/SCOND, the rwlock counter can be atomically updated w/o need
for a guarding spin lock.
This in turn elides the EXchange instruction based spinning which causes
the cacheline transition to exclusive state and concurrent spinning
across cores would cause the line to keep bouncing around.
LLOCK/SCOND based implementation is superior as spinning on LLOCK keeps
the cacheline in shared state.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Current spin_lock uses EXchange instruction to implement the atomic test
and set of lock location (reads orig value and ST 1). This however forces
the cacheline into exclusive state (because of the ST) and concurrent
loops in multiple cores will bounce the line around between cores.
Instead, use LLOCK/SCOND to implement the atomic test and set which is
better as line is in shared state while lock is spinning on LLOCK
The real motivation of this change however is to make way for future
changes in atomics to implement delayed retry (with backoff).
Initial experiment with delayed retry in atomics combined with orig
EX based spinlock was a total disaster (broke even LMBench) as
struct sock has a cache line sharing an atomic_t and spinlock. The
tight spinning on lock, caused the atomic retry to keep backing off
such that it would never finish.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This reduces the diff in forth-coming patches and also helps understand
better the incremental changes to inline asm.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Extended testing of quad core configuration revealed that this fix was
insufficient. Specifically LTP open posix shm_op/23-1 would cause the
hardware livelock in llock/scond loop in update_cpu_load_active()
So remove this and make way for a proper workaround
This reverts commit a5c8b52abe.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
With HS 2.1 release, the peripheral space register no longer contains
the uncached space specifics, causing the kernel to panic early on.
So read the newer NON VOLATILE AUX register to get that info.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Vineet Gupta <vgupta@synopsys.com>
Move the now generic definitions of atomic_{set,clear}_mask() into
linux/atomic.h to avoid endless and pointless repetition.
Also, provide an atomic_andnot() wrapper for those few archs that can
implement that.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Implement atomic logic ops -- atomic_{or,xor,and}.
These will replace the atomic_{set,clear}_mask functions that are
available on some archs.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Implement atomic logic ops -- atomic_{or,xor,and}.
These will replace the atomic_{set,clear}_mask functions that are
available on some archs.
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There are configurations which may not have LDD/STD
Signed-off-by: Claudiu Zissulescu <claziss@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Being highly configurable core ARC HS among other features might be
configured with or without DIV_REM_OPTION (hardware divider).
That option when enabled adds following instructions: div, divu, rem, remu.
By default ARC HS38 has this option enabled. So we add here possibility
to disable usage of hardware divider by compiler.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Migrate arc driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.
This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Commit 2ae416b142 ("mm: new mm hook framework") introduced an empty
header file (mm-arch-hooks.h) for every architecture, even those which
doesn't need to define mm hooks.
As suggested by Geert Uytterhoeven, this could be cleaned through the use
of a generic header file included via each per architecture
asm/include/Kbuild file.
The PowerPC architecture is not impacted here since this architecture has
to defined the arch_remap MM hook.
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently instruction_pointer() returns pt_regs->ret and so return value
is of type "long", which implicitly stands for "signed long".
While that's perfectly fine when dealing with 32-bit values if return
value of instruction_pointer() gets assigned to 64-bit variable sign
extension may happen.
And at least in one real use-case it happens already.
In perf_prepare_sample() return value of perf_instruction_pointer()
(which is an alias to instruction_pointer() in case of ARC) is assigned
to (struct perf_sample_data)->ip (which type is "u64").
And what we see if instuction pointer points to user-space application
that in case of ARC lays below 0x8000_0000 "ip" gets set properly with
leading 32 zeros. But if instruction pointer points to kernel address
space that starts from 0x8000_0000 then "ip" is set with 32 leadig
"f"-s. I.e. id instruction_pointer() returns 0x8100_0000, "ip" will be
assigned with 0xffff_ffff__8100_0000. Which is obviously wrong.
In particular that issuse broke output of perf, because perf was unable
to associate addresses like 0xffff_ffff__8100_0000 with anything from
/proc/kallsyms.
That's what we used to see:
----------->8----------
6.27% ls [unknown] [k] 0xffffffff8046c5cc
2.96% ls libuClibc-0.9.34-git.so [.] memcpy
2.25% ls libuClibc-0.9.34-git.so [.] memset
1.66% ls [unknown] [k] 0xffffffff80666536
1.54% ls libuClibc-0.9.34-git.so [.] 0x000224d6
1.18% ls libuClibc-0.9.34-git.so [.] 0x00022472
----------->8----------
With that change perf output looks much better now:
----------->8----------
8.21% ls [kernel.kallsyms] [k] memset
3.52% ls libuClibc-0.9.34-git.so [.] memcpy
2.11% ls libuClibc-0.9.34-git.so [.] malloc
1.88% ls libuClibc-0.9.34-git.so [.] memset
1.64% ls [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore
1.41% ls [kernel.kallsyms] [k] __d_lookup_rcu
----------->8----------
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: arc-linux-dev@synopsys.com
Cc: stable@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The IRQCHIP_DECLARE macro migrated to 'include/linux/irqchip.h'.
See commit 91e20b5040
("irqchip: Move IRQCHIP_DECLARE macro to include/linux/irqchip.h").
This patch removes the inclusions of private header 'drivers/irqchip/irqchip.h'
and if necessary replaces them with inclusions of 'include/linux/irqchip.h'.
Signed-off-by: Joel Porquet <joel@porquet.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARCompact/ARCv2 ISA provide that any instructions which deals with
bitpos/count operand ASL, LSL, BSET, BCLR, BMSK .... will only consider
lower 5 bits. i.e. auto-clamp the pos to 0-31.
ARC Linux bitops exploited this fact by NOT explicitly masking out upper
bits for @nr operand in general, saving a bunch of AND/BMSK instructions
in generated code around bitops.
While this micro-optimization has worked well over years it is NOT safe
as shifting a number with a value, greater than native size is
"undefined" per "C" spec.
So as it turns outm EZChip ran into this eventually, in their massive
muti-core SMP build with 64 cpus. There was a test_bit() inside a loop
from 63 to 0 and gcc was weirdly optimizing away the first iteration
(so it was really adhering to standard by implementing undefined behaviour
vs. removing all the iterations which were phony i.e. (1 << [63..32])
| for i = 63 to 0
| X = ( 1 << i )
| if X == 0
| continue
So fix the code to do the explicit masking at the expense of generating
additional instructions. Fortunately, this can be mitigated to a large
extent as gcc has SHIFT_COUNT_TRUNCATED which allows combiner to fold
masking into shift operation itself. It is currently not enabled in ARC
gcc backend, but could be done after a bit of testing.
Fixes STAR 9000866918 ("unsafe "undefined behavior" code in kernel")
Reported-by: Noam Camus <noamc@ezchip.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
With up-to-date FPGA builds ARC cores are supposed to correctly operate
even with 90 MHz clock (which is a target frequency for AXS103 release).
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: arc-linux-dev@synopsys.com
Added the x86 implementation of word-at-a-time to the
generic version, which previously only supported big-endian.
Omitted the x86-specific load_unaligned_zeropad(), which in
any case is also not present for the existing BE-only
implementation of a word-at-a-time, and is only used under
CONFIG_DCACHE_WORD_ACCESS.
Added as a "generic-y" to the Kbuilds of all architectures
that didn't previously have it.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
With this nsim standlone / OSCI have working irq affinity - AXS103 still
needs some work as IDU is not visible in intc hierarchy yet !
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
alloc_pages_exact() get gfp flags and handle zero'ing already
And while it, fix the case where ioremap fails: return rightaway.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC kernels have historically been built with -O3, despite top level
Makefile defaulting to -O2. This was facilitated by implicitly ordering
of arch makefile include AFTER top level assigned -O2.
An upstream fix to top level a1c48bb160 ("Makefile: Fix unrecognized
cross-compiler command line options") changed the ordering, making ARC
-O3 defunct.
Fix that by NOT relying on any ordering whatsoever and use the proper
arch override facility now present in kbuild (ARCH_*FLAGS)
Depends-on: ("kbuild: Allow arch Makefiles to override {cpp,ld,c}flags")
Suggested-by: Michal Marek <mmarek@suse.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
SLC maintenance ops need to be serialized by software as there is no
inherent buffering / quequing of aux commands. It can silently ignore a
new aux operation if previous one is still ongoing (SLC_CTRL_BUSY)
So gaurd the SLC op using a spin lock
The spin lock doesn't seem to be contended even in heavy workloads such
as iperf. On FPGA @ 75 MHz.
[1] Before this change:
============================================================
# iperf -c 10.42.0.1
------------------------------------------------------------
Client connecting to 10.42.0.1, TCP port 5001
TCP window size: 43.8 KByte (default)
------------------------------------------------------------
[ 3] local 10.42.0.110 port 38935 connected with 10.42.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 48.4 MBytes 40.6 Mbits/sec
============================================================
[2] After this change:
============================================================
# iperf -c 10.42.0.1
------------------------------------------------------------
Client connecting to 10.42.0.1, TCP port 5001
TCP window size: 43.8 KByte (default)
------------------------------------------------------------
[ 3] local 10.42.0.243 port 60248 connected with 10.42.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 47.5 MBytes 39.8 Mbits/sec
# iperf -c 10.42.0.1
------------------------------------------------------------
Client connecting to 10.42.0.1, TCP port 5001
TCP window size: 43.8 KByte (default)
------------------------------------------------------------
[ 3] local 10.42.0.243 port 60249 connected with 10.42.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 54.9 MBytes 46.0 Mbits/sec
============================================================
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: arc-linux-dev@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
Merge third patchbomb from Andrew Morton:
- the rest of MM
- scripts/gdb updates
- ipc/ updates
- lib/ updates
- MAINTAINERS updates
- various other misc things
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits)
genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()
genalloc: rename dev_get_gen_pool() to gen_pool_get()
x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit
MAINTAINERS: add zpool
MAINTAINERS: BCACHE: Kent Overstreet has changed email address
MAINTAINERS: move Jens Osterkamp to CREDITS
MAINTAINERS: remove unused nbd.h pattern
MAINTAINERS: update brcm gpio filename pattern
MAINTAINERS: update brcm dts pattern
MAINTAINERS: update sound soc intel patterns
MAINTAINERS: remove website for paride
MAINTAINERS: update Emulex ocrdma email addresses
bcache: use kvfree() in various places
libcxgbi: use kvfree() in cxgbi_free_big_mem()
target: use kvfree() in session alloc and free
IB/ehca: use kvfree() in ipz_queue_{cd}tor()
drm/nouveau/gem: use kvfree() in u_free()
drm: use kvfree() in drm_free_large()
cxgb4: use kvfree() in t4_free_mem()
cxgb3: use kvfree() in cxgb_free_mem()
...
ARCv2 is the next generation ISA from Synopsys and basis for the
HS3{4,6,8} families of processors which retain the traditional ARC mantra of
low power and configurability and are now more performant and feature rich.
HS38x is a 10 stage pipeline core which supports MMU (with huge pages) and
SMP (upto 4 cores) among other features.
+ www.synopsys.com/dw/ipdir.php?ds=arc-hs38-processor
+ http://news.synopsys.com/2014-10-14-New-DesignWare-ARC-HS38-Processor-Doubles-Performance-for-Embedded-Linux-Applications
+ http://www.embedded.com/electronics-news/4435975/Synopsys-ARC-HS38-core-gives-2X-boost-to-Linux-based-apps
- Support for ARC SDP (Software Development platform): Main Board + CPU Cards
= AXS101: CPU Card with ARC700 in silicon @ 700 MHz
= AXS103: CPU Card with HS38x in FPGA
- Refactoring of ARCompact port to accomodate new ARCv2 ISA
- Miscll updates/cleanups
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Merge tag 'arc-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC architecture updates from Vineet Gupta:
- support for HS38 cores based on ARCv2 ISA
ARCv2 is the next generation ISA from Synopsys and basis for the
HS3{4,6,8} families of processors which retain the traditional ARC mantra of
low power and configurability and are now more performant and feature rich.
HS38x is a 10 stage pipeline core which supports MMU (with huge pages) and
SMP (upto 4 cores) among other features.
+ www.synopsys.com/dw/ipdir.php?ds=arc-hs38-processor
+ http://news.synopsys.com/2014-10-14-New-DesignWare-ARC-HS38-Processor-Doubles-Performance-for-Embedded-Linux-Applications
+ http://www.embedded.com/electronics-news/4435975/Synopsys-ARC-HS38-core-gives-2X-boost-to-Linux-based-apps
- support for ARC SDP (Software Development platform): Main Board + CPU Cards
= AXS101: CPU Card with ARC700 in silicon @ 700 MHz
= AXS103: CPU Card with HS38x in FPGA
- refactoring of ARCompact port to accomodate new ARCv2 ISA
- misc updates/cleanups
* tag 'arc-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (72 commits)
ARC: Fix build failures for ARCompact in linux-next after ARCv2 support
ARCv2: Allow older gcc to cope with new regime of ARCv2/ARCompact support
ARCv2: [vdk] dts files and defconfig for HS38 VDK
ARCv2: [axs103] Support ARC SDP FPGA platform for HS38x cores
ARC: [axs101] Prepare for AXS103
ARCv2: [nsim*hs*] Support simulation platforms for HS38x cores
ARCv2: All bits in place, allow ARCv2 builds
ARCv2: SLC: Handle explcit flush for DMA ops (w/o IO-coherency)
ARCv2: STAR 9000837815 workaround hardware exclusive transactions livelock
ARC: Reduce bitops lines of code using macros
ARCv2: barriers
arch: conditionally define smp_{mb,rmb,wmb}
ARC: add smp barriers around atomics per Documentation/atomic_ops.txt
ARC: add compiler barrier to LLSC based cmpxchg
ARCv2: SMP: intc: IDU 2nd level intc for dynamic IRQ distribution
ARCv2: SMP: clocksource: Enable Global Real Time counter
ARCv2: SMP: ARConnect debug/robustness
ARCv2: SMP: Support ARConnect (MCIP) for Inter-Core-Interrupts et al
ARC: make plat_smp_ops weak to allow over-rides
ARCv2: clocksource: Introduce 64bit local RTC counter
...
This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls. Since arc doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element. But this can help find problems with
drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-no-ll64 is specific to ARCv2 ISA, and is obviously not supported by
older ARC gcc - in this case the one hosted by linux-next sanity build
service.
Ensure that it doesn't get included for ISA_ARCOMPACT
Reported-by: Guenter Roeck <private@roeck-us.net>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull asm/scatterlist.h removal from Jens Axboe:
"We don't have any specific arch scatterlist anymore, since parisc
finally switched over. Kill the include"
* 'for-4.2/sg' of git://git.kernel.dk/linux-block:
remove scatterlist.h generation from arch Kbuild files
remove <asm/scatterlist.h>
CRIU is recreating the process memory layout by remapping the checkpointee
memory area on top of the current process (criu). This includes remapping
the vDSO to the place it has at checkpoint time.
However some architectures like powerpc are keeping a reference to the
vDSO base address to build the signal return stack frame by calling the
vDSO sigreturn service. So once the vDSO has been moved, this reference
is no more valid and the signal frame built later are not usable.
This patch serie is introducing a new mm hook framework, and a new
arch_remap hook which is called when mremap is done and the mm lock still
hold. The next patch is adding the vDSO remap and unmap tracking to the
powerpc architecture.
This patch (of 3):
This patch introduces a new set of header file to manage mm hooks:
- per architecture empty header file (arch/x/include/asm/mm-arch-hooks.h)
- a generic header (include/linux/mm-arch-hooks.h)
The architecture which need to overwrite a hook as to redefine it in its
header file, while architecture which doesn't need have nothing to do.
The default hooks are defined in the generic header and are used in the
case the architecture is not defining it.
In a next step, mm hooks defined in include/asm-generic/mm_hooks.h should
be moved here.
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- CONFIG_ARC_UBOOT_SUPPORT to handle arguments passed in r0, r1, r2
- CONFIG_DEVTMPFS_MOUNT for mouting rootfs since it uses external cpio
for rootfs
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Ruud Derwig <rderwig@synopsys.com>
[vgupta: folded the Main baord DT files for smp/up into one]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
To avoid duplicating the MB DTS file, move the MB intc entry into cpu
card specific file
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
L2 cache on ARCHS processors is called SLC (System Level Cache)
For working DMA (in absence of hardware assisted IO Coherency) we need
to manage SLC explicitly when buffers transition between cpu and
controllers.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
A quad core SMP build could get into hardware livelock with concurrent
LLOCK/SCOND. Workaround that by adding a PREFETCHW which is serialized by
SCU (System Coherency Unit). It brings the cache line in Exclusive state
and makes others invalidate their lines. This gives enough time for
winner to complete the LLOCK/SCOND, before others can get the line back.
The prefetchw in the ll/sc loop is not nice but this is the only
software workaround for current version of RTL.
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARCv2 based HS38 cores are weakly ordered and thus explicit barriers for
kernel proper.
SMP barrier is provided by DMB instruction which also guarantees local
barrier hence used as backend of smp_*mb() as well as *mb() APIs
Also hookup barriers into MMIO accessors to avoid ordering issues in IO
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
- arch_spin_lock/unlock were lacking the ACQUIRE/RELEASE barriers
Since ARCv2 only provides load/load, store/store and all/all, we need
the full barrier
- LLOCK/SCOND based atomics, bitops, cmpxchg, which return modified
values were lacking the explicit smp barriers.
- Non LLOCK/SCOND varaints don't need the explicit barriers since that
is implicity provided by the spin locks used to implement the
critical section (the spin lock barriers in turn are also fixed in
this commit as explained above
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
When auditing cmpxchg call sites, Chuck noted that gcc was optimizing
away some of the desired LDs.
| do {
| new = old = *ipi_data_ptr;
| new |= 1U << msg;
| } while (cmpxchg(ipi_data_ptr, old, new) != old);
was generating to below
| 8015cef8: ld r2,[r4,0] <-- First LD
| 8015cefc: bset r1,r2,r1
|
| 8015cf00: llock r3,[r4] <-- atomic op
| 8015cf04: brne r3,r2,8015cf10
| 8015cf08: scond r1,[r4]
| 8015cf0c: bnz 8015cf00
|
| 8015cf10: brne r3,r2,8015cf00 <-- Branch doesn't go to orig LD
Although this was fixed by adding a ACCESS_ONCE in this call site, it
seems safer (for now at least) to add compiler barrier to LLSC based
cmpxchg
Reported-by: Chuck Jordan <cjordan@synopsys,com>
Cc: <stable@vger.kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull x86 core updates from Ingo Molnar:
"There were so many changes in the x86/asm, x86/apic and x86/mm topics
in this cycle that the topical separation of -tip broke down somewhat -
so the result is a more traditional architecture pull request,
collected into the 'x86/core' topic.
The topics were still maintained separately as far as possible, so
bisectability and conceptual separation should still be pretty good -
but there were a handful of merge points to avoid excessive
dependencies (and conflicts) that would have been poorly tested in the
end.
The next cycle will hopefully be much more quiet (or at least will
have fewer dependencies).
The main changes in this cycle were:
* x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
Gleixner)
- This is the second and most intrusive part of changes to the x86
interrupt handling - full conversion to hierarchical interrupt
domains:
[IOAPIC domain] -----
|
[MSI domain] --------[Remapping domain] ----- [ Vector domain ]
| (optional) |
[HPET MSI domain] ----- |
|
[DMAR domain] -----------------------------
|
[Legacy domain] -----------------------------
This now reflects the actual hardware and allowed us to distangle
the domain specific code from the underlying parent domain, which
can be optional in the case of interrupt remapping. It's a clear
separation of functionality and removes quite some duct tape
constructs which plugged the remap code between ioapic/msi/hpet
and the vector management.
- Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
injection into guests (Feng Wu)
* x86/asm changes:
- Tons of cleanups and small speedups, micro-optimizations. This
is in preparation to move a good chunk of the low level entry
code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
Brian Gerst)
- Moved all system entry related code to a new home under
arch/x86/entry/ (Ingo Molnar)
- Removal of the fragile and ugly CFI dwarf debuginfo annotations.
Conversion to C will reintroduce many of them - but meanwhile
they are only getting in the way, and the upstream kernel does
not rely on them (Ingo Molnar)
- NOP handling refinements. (Borislav Petkov)
* x86/mm changes:
- Big PAT and MTRR rework: making the code more robust and
preparing to phase out exposing direct MTRR interfaces to drivers -
in favor of using PAT driven interfaces (Toshi Kani, Luis R
Rodriguez, Borislav Petkov)
- New ioremap_wt()/set_memory_wt() interfaces to support
Write-Through cached memory mappings. This is especially
important for good performance on NVDIMM hardware (Toshi Kani)
* x86/ras changes:
- Add support for deferred errors on AMD (Aravind Gopalakrishnan)
This is an important RAS feature which adds hardware support for
poisoned data. That means roughly that the hardware marks data
which it has detected as corrupted but wasn't able to correct, as
poisoned data and raises an APIC interrupt to signal that in the
form of a deferred error. It is the OS's responsibility then to
take proper recovery action and thus prolonge system lifetime as
far as possible.
- Add support for Intel "Local MCE"s: upcoming CPUs will support
CPU-local MCE interrupts, as opposed to the traditional system-
wide broadcasted MCE interrupts (Ashok Raj)
- Misc cleanups (Borislav Petkov)
* x86/platform changes:
- Intel Atom SoC updates
... and lots of other cleanups, fixlets and other changes - see the
shortlog and the Git log for details"
* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
x86/hpet: Use proper hpet device number for MSI allocation
x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
genirq: Prevent crash in irq_move_irq()
genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
iommu, x86: Properly handle posted interrupts for IOMMU hotplug
iommu, x86: Provide irq_remapping_cap() interface
iommu, x86: Setup Posted-Interrupts capability for Intel iommu
iommu, x86: Add cap_pi_support() to detect VT-d PI capability
iommu, x86: Avoid migrating VT-d posted interrupts
iommu, x86: Save the mode (posted or remapped) of an IRTE
iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
iommu: dmar: Provide helper to copy shared irte fields
iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
iommu: Add new member capability to struct irq_remap_ops
x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
...
This allows platforms to provide their own cpu wakeup routines
as well as IPI send / clear backends, while allowing a SMP kernel w/o
any such backend to build/boot
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Caveats about cache flush on ARCv2 based cores
- dcache is PIPT so paddr is sufficient for cache maintenance ops (no
need to setup PTAG reg
- icache is still VIPT but only aliasing configs need PTAG setup
So basically this is departure from MMU-v3 which always need vaddr in
line ops registers (DC_IVDL, DC_FLDL, IC_IVIL) but paddr in DC_PTAG,
IC_PTAG respectively.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The issue was, on HS when interrupt is taken, IRQ_ACT is set and that is
NOT cleared unless we do RTIE (or manually clear it). Linux interrupt
handling has top and bottom halves. Latter lead to softirqs (which can
reschedule) AND expect interrupts to be REALLY re-enabled which was NOT
happening for us since we only SETI, dont clear IRQ_ACT
So we can have a state when both cores have taken interrupt (IRQ_ACT set),
get rescheduled, both send IPI and wait in CSD lock which will never be
cleared as cores can't take the pending IPI IRQ due to existing IRQ_ACT
set.
So local_irq_enable() now drops the IRQ_ACT.act bit to re-enable IRQs.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reported by Anton as LTP:munmap01 failing with Illegal Instruction
Exception.
--------------------->8--------------------------------------
mmap2(NULL, 24576, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = 0x200d2000
munmap(0x200d2000, 24576) = 0
--- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x200d2000}
---
potentially unexpected fatal signal 4.
Path: /munmap01
CPU: 0 PID: 61 Comm: munmap01 Not tainted 3.13.0-g5d5c46d9a556 #8
task: 9f1a8000 ti: 9f154000 task.ti: 9f154000
[ECR ]: 0x00020100 => Illegal Insn
[EFA ]: 0x0001354c
[BLINK ]: 0x200515d4
[ERET ]: 0x1354c
@off 0x1354c in [/munmap01]
VMA: 0x00010000 to 0x00018000
[STAT32]: 0x800802c0
...
--------------------->8--------------------------------------
The issue was
1. munmap01 accessed unmapped memory (on purpose) with signal handler
installed for SIGSEGV
2. The faulting instruction happened to be in Delay Slot
00011864 <main>:
11908: bl.d 13284 <tst_resm>
1190c: stb r16,[r2]
3. kernel sets up the reg file for signal handler and correctly clears
the DE bit in pt_regs->status32 placeholder
4. However RESTORE_CALLEE_SAVED_USER macro is not adjusted for ARCv2,
and it over-writes the above with orig/stale value of status32
5. After RTIE, userspace signal handler executes a non branch
instruction with DE bit set, triggering Illegal Instruction Exception.
Reported-by: Anton Kolesov <akolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
These have been register compatible so far. However ARCv2 mandates
different pt_regs layout (due to h/w auto save). To keep pt_regs same
for both, we start by removing the assumption - used mainly for block
copies between the 2 structs in signal handling and ptrace
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Previously this macro was overloaded with stack switching, saving SP at right
slot in pt_regs, saving/setup of r25 and setting SP baseline to where
pt_regs->sp is saved (vs. bottom of pt_regs)
Now it only does SP switch, and leaves SP pointing to bottom of pt_regs.
r25 saving is no longer done here to allow for future reordering of
regfile in pt_regs w/o touching this macro
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Returning from pure kernel mode and exception mode use the same code
anyways. Remove one the duplicate blocks
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Elide the need to re-read ECR in Trap handler by ensuring that
EXCEPTION_PROLOGUE does that at the very end just before returning
to Trap handler
ARCv2 EXCEPTION_PROLOGUE already did that, so same for ARcompact and the
common trap handler adjusted to use cached ECR
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This fixes the possible link/relo errors, since restore_regs will be
provided by ISA code, but called from ARC common code.
The .L prefix reassures binutils that it will be in same compilation
unit.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
- Remove the ifdef'ery and write distinct versions for each mmu ver even
if there is some code duplication
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
That is because __after_dc_op() already reads it for status check, so it
is better anyways to use that "newer" value.
Also reduces the clutter in callers for passing from/to these routines.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
As DW Mobile Storage databook says it's required to use "Hold Register"
if card is enumerated in SDR12 or SDR25 modes.
It means we need to act in the same way as in Altera's Socfpga
implementation - set "use hold reg" bit in commad.
Note that for upstream proper solution would be to remove
dw_mci_pltfm_prepare_command() at all and set the bit right in
dw_mci_prepare_command() for all platforms.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Earlycon calculates UART clock as "BASE_BAUD * 16". In case of ARC
"BASE_BAUD" is calculated dynamically in runtime, basically it is an
alias to arc_early_base_baud(), which in turn just does
"arc_base_baud/16".
8250 UART on AXS/SDP board uses 33.3MHz clock source which is set in
"arc_base_baud" with this change.
Additional compatibility string "snps,arc-sdp" is introduced as well
because there're different flavours of AXS boards but they all share the
same motherboard and so it's possible to re-use the same code for
motherbord even if CPU daughterboard changes.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The AXS10x platforms consist of a mainboard with peripherals,
on which several daughter cards can be placed. The daughter cards
typically contain a CPU and memory.
Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Currently, it doesn't invoke the callback but continues to unwind
Also while at it - simplify the code a bit
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Directly return the result of perf_pmu_register() in
arc_pmu_device_probe() instead of assigning and returning variable ret.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
static arc_pmu in the arch/arc/kernel/perf_event.c is not initialized as
it's shadowed by a local variable of the same name in the
arc_pmu_device_probe.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Fixes: 03c94fcf95 "ARC: perf: make @arc_pmu static global"
CC: <stable@vger.kernel.org> # 4.1
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* Remove remanants of legacy ARC FPGA platforms (AA4, ML509...)
* Only nsim simulation platform is left, rename platform accordingly
* AA4 DT stuff is compatible with nsim for ARC700 so rename it too
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Back when ARC700 4.10 was released, the related kernel features were
tied to this config item so they could be disabled in one shot (i.e.
LLOCK/SCOND, SWAPE, RTSC..)
That having happened a while back, all new ARC customers weill get 4.11+
so those features can be assumed to be present and need not be tied to a
top-level (we still retain the ability to individually disable them).
Further, since ARCv2 also shares some of those feautes, removing it
simplifies things a bit in Kconfig
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Add ioremap_wt() to all arch-specific asm/io.h headers which
define ioremap_wc() locally. These headers do not include
<asm-generic/iomap.h>. Some of them include <asm-generic/io.h>,
but ioremap_wt() is defined for consistency since they define
all ioremap_xxx locally.
In all architectures without Write-Through support, ioremap_wt()
is defined indentical to ioremap_nocache().
frv and m68k already have ioremap_writethrough(). On those we
add ioremap_wt() indetical to ioremap_writethrough() and defines
ARCH_HAS_IOREMAP_WT in both architectures.
The ioremap_wt() interface is exported to drivers.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Elliott@hp.com
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: hch@lst.de
Cc: hmh@hmh.eng.br
Cc: jgross@suse.com
Cc: konrad.wilk@oracle.com
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-nvdimm@lists.01.org
Cc: stefan.bader@canonical.com
Cc: yigal@plexistor.com
Link: http://lkml.kernel.org/r/1433436928-31903-9-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.
Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).
In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().
Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.
faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.
This patch is based on a patch from Thomas Gleixner.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ARC GNU tools have had support for arc-linux-* driver for some time now.
This is functionally similar to arc-linux-uclibc-* but uclibc prefix
seemed weird at best when trying to compile the kernel itself.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
print_task_path_n_nm() is local to this file, its only user being
show_regs(). Mark the function static and avoid the EXPORT_SYMBOL.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Vineet Gupta <vgupta@synoipsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull exec domain removal from Richard Weinberger:
"This series removes execution domain support from Linux.
The idea behind exec domains was to support different ABIs. The
feature was never complete nor stable. Let's rip it out and make the
kernel signal handling code less complicated"
* 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (27 commits)
arm64: Removed unused variable
sparc: Fix execution domain removal
Remove rest of exec domains.
arch: Remove exec_domain from remaining archs
arc: Remove signal translation and exec_domain
xtensa: Remove signal translation and exec_domain
xtensa: Autogenerate offsets in struct thread_info
x86: Remove signal translation and exec_domain
unicore32: Remove signal translation and exec_domain
um: Remove signal translation and exec_domain
tile: Remove signal translation and exec_domain
sparc: Remove signal translation and exec_domain
sh: Remove signal translation and exec_domain
s390: Remove signal translation and exec_domain
mn10300: Remove signal translation and exec_domain
microblaze: Remove signal translation and exec_domain
m68k: Remove signal translation and exec_domain
m32r: Remove signal translation and exec_domain
m32r: Autogenerate offsets in struct thread_info
frv: Remove signal translation and exec_domain
...
Pull vfs update from Al Viro:
"Part one:
- struct filename-related cleanups
- saner iov_iter_init() replacements (and switching the syscalls to
use of those)
- ntfs switch to ->write_iter() (Anton)
- aio cleanups and splitting iocb into common and async parts
(Christoph)
- assorted fixes (me, bfields, Andrew Elble)
There's a lot more, including the completion of switchover to
->{read,write}_iter(), d_inode/d_backing_inode annotations, f_flags
race fixes, etc, but that goes after #for-davem merge. David has
pulled it, and once it's in I'll send the next vfs pull request"
* 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (35 commits)
sg_start_req(): use import_iovec()
sg_start_req(): make sure that there's not too many elements in iovec
blk_rq_map_user(): use import_single_range()
sg_io(): use import_iovec()
process_vm_access: switch to {compat_,}import_iovec()
switch keyctl_instantiate_key_common() to iov_iter
switch {compat_,}do_readv_writev() to {compat_,}import_iovec()
aio_setup_vectored_rw(): switch to {compat_,}import_iovec()
vmsplice_to_user(): switch to import_iovec()
kill aio_setup_single_vector()
aio: simplify arguments of aio_setup_..._rw()
aio: lift iov_iter_init() into aio_setup_..._rw()
lift iov_iter into {compat_,}do_readv_writev()
NFS: fix BUG() crash in notify_change() with patch to chown_common()
dcache: return -ESTALE not -EBUSY on distributed fs race
NTFS: Version 2.1.32 - Update file write from aio_write to write_iter.
VFS: Add iov_iter_fault_in_multipages_readable()
drop bogus check in file_open_root()
switch security_inode_getattr() to struct path *
constify tomoyo_realpath_from_path()
...
Pull trivial tree from Jiri Kosina:
"Usual trivial tree updates. Nothing outstanding -- mostly printk()
and comment fixes and unused identifier removals"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
goldfish: goldfish_tty_probe() is not using 'i' any more
powerpc: Fix comment in smu.h
qla2xxx: Fix printks in ql_log message
lib: correct link to the original source for div64_u64
si2168, tda10071, m88ds3103: Fix firmware wording
usb: storage: Fix printk in isd200_log_config()
qla2xxx: Fix printk in qla25xx_setup_mode
init/main: fix reset_device comment
ipwireless: missing assignment
goldfish: remove unreachable line of code
coredump: Fix do_coredump() comment
stacktrace.h: remove duplicate declaration task_struct
smpboot.h: Remove unused function prototype
treewide: Fix typo in printk messages
treewide: Fix typo in printk messages
mod_devicetable: fix comment for match_flags
This makes test_bit() more like its siblings *_bit() routines.
Also add some comments about the constant @nr micro-optimization
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
As execution domain support is gone we can remove
signal translation from the signal code and remove
exec_domain from thread_info.
Signed-off-by: Richard Weinberger <richard@nod.at>
flush_old_exec() has already done that. Back on 2011 a bunch of
instances like that had been kicked out, but that hadn't taken
care of then-out-of-tree architectures, obviously, and they served
as reinfection vector...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The 'arg' argument to copy_thread() is only ever used when forking a new
kernel thread. Hence, rename it to 'kthread_arg' for clarity.
Signed-off-by: Alex Dowad <alexinbeijing@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
A malicious signal handler / restorer can DOS the system by fudging the
user regs saved on stack, causing weird things such as sigreturn returning
to user mode PC but cpu state still being kernel mode....
Ensure that in sigreturn path status32 always has U bit; any other bogosity
(gargbage PC etc) will be taken care of by normal user mode exceptions mechanisms.
Reproducer signal handler:
void handle_sig(int signo, siginfo_t *info, void *context)
{
ucontext_t *uc = context;
struct user_regs_struct *regs = &(uc->uc_mcontext.regs);
regs->scratch.status32 = 0;
}
Before the fix, kernel would go off to weeds like below:
--------->8-----------
[ARCLinux]$ ./signal-test
Path: /signal-test
CPU: 0 PID: 61 Comm: signal-test Not tainted 4.0.0-rc5+ #65
task: 8f177880 ti: 5ffe6000 task.ti: 8f15c000
[ECR ]: 0x00220200 => Invalid Write @ 0x00000010 by insn @ 0x00010698
[EFA ]: 0x00000010
[BLINK ]: 0x2007c1ee
[ERET ]: 0x10698
[STAT32]: 0x00000000 : <--------
BTA: 0x00010680 SP: 0x5ffe7e48 FP: 0x00000000
LPS: 0x20003c6c LPE: 0x20003c70 LPC: 0x00000000
...
--------->8-----------
Reported-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The regfile provided to SA_SIGINFO signal handler as ucontext was off by
one due to pt_regs gutter cleanups in 2013.
Before handling signal, user pt_regs are copied onto user_regs_struct and copied
back later. Both structs are binary compatible. This was all fine until
commit 2fa919045b (ARC: pt_regs update #2) which removed the empty stack slot
at top of pt_regs (corresponding to first pad) and made the corresponding
fixup in struct user_regs_struct (the pad in there was moved out of
@scratch - not removed altogether as it is part of ptrace ABI)
struct user_regs_struct {
+ long pad;
struct {
- long pad;
long bta, lp_start, lp_end,....
} scratch;
...
}
This meant that now user_regs_struct was off by 1 reg w.r.t pt_regs and
signal code needs to user_regs_struct.scratch to reflect it as pt_regs,
which is what this commit does.
This problem was hidden for 2 years, because both save/restore, despite
using wrong location, were using the same location. Only an interim
inspection (reproducer below) exposed the issue.
void handle_segv(int signo, siginfo_t *info, void *context)
{
ucontext_t *uc = context;
struct user_regs_struct *regs = &(uc->uc_mcontext.regs);
printf("regs %x %x\n", <=== prints 7 8 (vs. 8 9)
regs->scratch.r8, regs->scratch.r9);
}
int main()
{
struct sigaction sa;
sa.sa_sigaction = handle_segv;
sa.sa_flags = SA_SIGINFO;
sigemptyset(&sa.sa_mask);
sigaction(SIGSEGV, &sa, NULL);
asm volatile(
"mov r7, 7 \n"
"mov r8, 8 \n"
"mov r9, 9 \n"
"mov r10, 10 \n"
:::"r7","r8","r9","r10");
*((unsigned int*)0x10) = 0;
}
Fixes: 2fa919045b "ARC: pt_regs update #2: Remove unused gutter at start of pt_regs"
CC: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The old implementation assumed that SP at the time of __switch_to() is
right above pt_regs which is almost certainly not the case as there will
be some stack build up between entry into kernel and leading up to
__switch_to
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
/proc/<pid>/maps currently don't annotate stack vma with "[stack]"
This is because KSTK_ESP ie expected to return usermode SP of tsk while
currently it returns the kernel mode SP of a sleeping tsk.
While the fix is trivial, we also need to adjust the ARC kernel stack
unwinder to not use KSTK_SP and friends any more.
Cc: <stable@vger.kernel.org>
Reported-and-suggested-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The arc unwinder can also be used for perf callchains.
Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull dmaengine updates from Vinod Koul:
"This update brings:
- the big cleanup up by Maxime for device control and slave
capabilities. This makes the API much cleaner.
- new IMG MDC driver by Andrew
- new Renesas R-Car Gen2 DMA Controller driver by Laurent along with
bunch of fixes on rcar drivers
- odd fixes and updates spread over driver"
* 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (130 commits)
dmaengine: pl330: add DMA_PAUSE feature
dmaengine: pl330: improve pl330_tx_status() function
dmaengine: rcar-dmac: Disable channel 0 when using IOMMU
dmaengine: rcar-dmac: Work around descriptor mode IOMMU errata
dmaengine: rcar-dmac: Allocate hardware descriptors with DMAC device
dmaengine: rcar-dmac: Fix oops due to unintialized list in error ISR
dmaengine: rcar-dmac: Fix spinlock issues in interrupt
dmaenegine: edma: fix sparse warnings
dmaengine: rcar-dmac: Fix uninitialized variable usage
dmaengine: shdmac: extend PM methods
dmaengine: shdmac: use SET_RUNTIME_PM_OPS()
dmaengine: pl330: fix bug that cause start the same descs in cyclic
dmaengine: at_xdmac: allow muliple dwidths when doing slave transfers
dmaengine: at_xdmac: simplify channel configuration stuff
dmaengine: at_xdmac: introduce save_cc field
dmaengine: at_xdmac: wait for in-progress transaction to complete after pausing a channel
ioat: fail self-test if wait_for_completion times out
dmaengine: dw: define DW_DMA_MAX_NR_MASTERS
dmaengine: dw: amend description of dma_dev field
dmatest: move src_off, dst_off, len inside loop
...
Some fixes, nothing too exciting this time as well...
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Merge tag 'arc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta:
"Some fixes, nothing too exciting this time as well..."
* tag 'arc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: fix page address calculation if PAGE_OFFSET != LINUX_LINK_BASE
ARC: Fix earlycon build breakage
ARC: Dynamically determine BASE_BAUD from DeviceTree
arc: Remove unused prepare_to_copy()
ARC: use ACCESS_ONCE in cmpxchg loop
ARC: add some more comments to ret_from_fork
ARC: fix /proc/cpuinfo for offline cpus
We used to calculate page address differently in 2 cases:
1. In virt_to_page(x) we do
--->8---
mem_map + (x - CONFIG_LINUX_LINK_BASE) >> PAGE_SHIFT
--->8---
2. In in pte_page(x) we do
--->8---
mem_map + (pte_val(x) - PAGE_OFFSET) >> PAGE_SHIFT
--->8---
That leads to problems in case PAGE_OFFSET != CONFIG_LINUX_LINK_BASE -
different pages will be selected depending on where and how we calculate
page address.
In particular in the STAR 9000853582 when gdb attempted to read memory
of another process it got improper page in get_user_pages() because this
is exactly one of the places where we search for a page by pte_page().
The fix is trivial - we need to calculate page address similarly in both
cases.
Cc: <stable@vger.kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target. This is because the
restart_block is held in the same memory allocation as the kernel stack.
Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.
Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.
It's also a decent simplification, since the restart code is more or less
identical on all architectures.
[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
LKP has triggered a compiler warning after my recent patch "mm: account
pmd page tables to the process":
mm/mmap.c: In function 'exit_mmap':
>> mm/mmap.c:2857:2: warning: right shift count >= width of type [enabled by default]
The code:
> 2857 WARN_ON(mm_nr_pmds(mm) >
2858 round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT);
In this, on tile, we have FIRST_USER_ADDRESS defined as 0. round_up() has
the same type -- int. PUD_SHIFT.
I think the best way to fix it is to define FIRST_USER_ADDRESS as unsigned
long. On every arch for consistency.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of using magic number in the code the patch provides
DW_DMA_MAX_NR_MASTERS constant.
While here, restrict the reading of data width array by amount of the actual
number of AHB masters.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit ffb7fcd66f ("ARC: Dynamically determine BASE_BAUD from DeviceTree")
breaks arc:defconfig build:
drivers/built-in.o: In function `of_setup_earlycon':
(.init.text+0xb3e): undefined reference to `arc_early_base_baud'
drivers/built-in.o: In function `setup_earlycon':
(.init.text+0xcd0): undefined reference to `arc_early_base_baud'
make: *** [vmlinux] Error 1
BASE_BAUD is only required for earlycon, which should depend on
CONFIG_SERIAL_EARLYCON.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
8250 earlycon is broken on multi-platform ARC because the UART clk
value (BASE_BAUD) is fixed at build time.
Instead, determine the appropriate UART clk at runtime; parse the
devicetree early for platforms requiring alternate UART clk values
(currently only the TB10X platform).
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Rob Herring <robh@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
prepare_to_copy() was removed from all architectures supported at that
time in commit 55ccf3fe3f ("fork: move the real prepare_to_copy()
users to arch_dup_task_struct()"). Remove it from arc as well.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d45 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'arc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull arch/arc updates from Vineet Gupta:
"Minor updates for ARC for 3.19"
* tag 'arc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: rename default defconfig
ARC: [nsimosci] move peripherals to match model to FPGA
ARC: document memory clobber in irq control macros
ARC: R-M-W assist locks only needed for !LLSC
ARC: add power management options
This allows the sdplite/Zebu images to run on OSCI simulation platform
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: <stable@vger.kernel.org> #3.10, 3.12, 3.14, 3.16
Vineet Gupta