Commit e1a5848e33 ("ARM: 7924/1: mm: don't bother with reserved ttbr0
when running with LPAE") removed the use of the reserved TTBR0 value
for LPAE systems, since the ASID is held in the TTBR and can be updated
atomicly with the pgd of the next mm.
Unfortunately, this patch forgot to update flush_context, which
deliberately avoids marking the local active ASID as allocated, since we
used to switch via ASID zero and didn't need to allocate the ASID of
the previous mm. The side-effect of this is that we can allocate the
same ASID to the next mm and, between flushing the local TLB and updating
TTBR0, we can perform speculative TLB fills for userspace nG mappings
using the page table of the previous mm.
The consequence of this is that the next mm can erroneously hit some
mappings of the previous mm. Note that this was made significantly
harder to hit by a391263cd8 ("ARM: 8203/1: mm: try to re-use old ASID
assignments following a rollover") but is still theoretically possible.
This patch fixes the problem by removing the code from flush_context
that forces the allocated ASID to zero for the local CPU. Many thanks
to the Broadcom guys for tracking this one down.
Fixes: e1a5848e33 ("ARM: 7924/1: mm: don't bother with reserved ttbr0 when running with LPAE")
Cc: <stable@vger.kernel.org> # v3.14+
Reported-by: Raymond Ngun <rngun@broadcom.com>
Tested-by: Raymond Ngun <rngun@broadcom.com>
Reviewed-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The recently added ARM_KERNMEM_PERMS feature works by manipulating
the kernel page tables, which obviously requires an MMU. Trying
to enable this feature when the MMU is disabled results in a lot
of compile errors in mm/init.c, so let's add a Kconfig dependency
to avoid that case.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When tearing down the DMA ops for a device via of_dma_deconfigure, we
unconditionally detach the device from its IOMMU domain. For devices
that aren't actually behind an IOMMU, this produces a "Not attached"
warning message on the console.
This patch changes the teardown code so that we don't detach from the
IOMMU domain when there isn't an IOMMU dma mapping to start with.
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In v3.19-rc3 tree when CONFIG_ARM_LPAE and CONFIG_DEBUG_RODATA are enabled
image failed to compile with the following error:
arch/arm/mm/init.c:661:14: error: ‘PMD_SECT_RDONLY’ undeclared here (not in a function)
It seems that '80d6b0c ARM: mm: allow text and rodata sections to be read-only'
and 'ded9477 ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE'
commits crossed. 80d6b0c uses PMD_SECT_RDONLY macro but ded9477 renames it
and uses software bits L_PMD_SECT_RDONLY instead.
Fix is to use L_PMD_SECT_RDONLY instead PMD_SECT_RDONLY as ded9477 does in
another places.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now local variables kernel_x_start and kernel_x_end defined using
'unsigned long' type which is wrong because they represent physical
memory range and will be calculated wrongly if LPAE is enabled.
As result, all following code in map_lowmem() will not work correctly.
For example, Keystone 2 boot is broken because
kernel_x_start == 0x0000 0000
kernel_x_end == 0x0080 0000
instead of
kernel_x_start == 0x0000 0008 0000 0000
kernel_x_end == 0x0000 0008 0080 0000
and as result whole low memory will be mapped with MT_MEMORY_RW
permissions by code (start > kernel_x_end):
} else if (start >= kernel_x_end) {
map.pfn = __phys_to_pfn(start);
map.virtual = __phys_to_virt(start);
map.length = end - start;
map.type = MT_MEMORY_RW;
create_mapping(&map);
}
Hence, fix it by using phys_addr_t type for variables kernel_x_start
and kernel_x_end.
Tested-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently the arm page table dumping code starts dumping page tables
from USER_PGTABLES_CEILING. This is unnecessary for skipping any entries
related to userspace as the swapper_pg_dir does not contain such
entries, and results in a couple of unfortuante side effects.
Firstly, any kernel mappings which might exist below
USER_PGTABLES_CEILING will not be accounted in the dump output. This
masks any entries erroneously created below this address.
Secondly, if the final page table entry walked is part of a valid
mapping the page table dumping code will not log the region this entry
is part of, as the final note_page call in walk_pgd will trigger an
early return when 0 < USER_PGTABLES_CEILING. Luckily this isn't seen on
contemporary systems as they typically don't have enough RAM to extend
the linear mapping right to the end of the address space.
Due to the way addr is constructed in the walk_* functions, it can never
be less than USER_PGTABLES_CEILING when walking the page tables, so it
is not necessary to avoid dereferencing invalid table addresses. The
existing checks for st->current_prot and st->marker[1].start_address are
sufficient to ensure we will not print and/or dereference garbage when
trying to log information.
This patch removes both problematic uses of USER_PGTABLES_CEILING from
the arm page table dumping code, preventing both of these issues. We
will now report any low mappings, and the final note_page call will not
return early, ensuring all regions are logged.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The iomm-config branch contains work from Will Deacon, quoting his description:
This series adds automatic IOMMU and DMA-mapping configuration for
OF-based DMA masters described using the generic IOMMU devicetree
bindings. Although there is plenty of future work around splitting up
iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU
group creation for the platform_bus, this is already useful enough for
people to port over their IOMMU drivers and start using the new probing
infrastructure (indeed, Marek has patches queued for the Exynos IOMMU).
The branch touches core ARM and IOMMU driver files, and the respective
maintainers (Russell King and Joerg Roedel) agreed to have the contents
merged through the arm-soc tree. The final version was ready just before
the merge window, so we ended up delaying it a bit longer than the rest,
but we don't expect to see regressions because this is just additional
infrastructure that will get used in drivers starting in 3.20 but is
unused so far.
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Merge tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC/iommu configuration update from Arnd Bergmann:
"The iomm-config branch contains work from Will Deacon, quoting his
description:
This series adds automatic IOMMU and DMA-mapping configuration for
OF-based DMA masters described using the generic IOMMU devicetree
bindings. Although there is plenty of future work around splitting up
iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU
group creation for the platform_bus, this is already useful enough for
people to port over their IOMMU drivers and start using the new probing
infrastructure (indeed, Marek has patches queued for the Exynos IOMMU).
The branch touches core ARM and IOMMU driver files, and the respective
maintainers (Russell King and Joerg Roedel) agreed to have the
contents merged through the arm-soc tree.
The final version was ready just before the merge window, so we ended
up delaying it a bit longer than the rest, but we don't expect to see
regressions because this is just additional infrastructure that will
get used in drivers starting in 3.20 but is unused so far"
* tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
iommu: store DT-probed IOMMU data privately
arm: dma-mapping: plumb our iommu mapping ops into arch_setup_dma_ops
arm: call iommu_init before of_platform_populate
dma-mapping: detect and configure IOMMU in of_dma_configure
iommu: fix initialization without 'add_device' callback
iommu: provide helper function to configure an IOMMU for an of master
iommu: add new iommu_ops callback for adding an OF device
dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops
iommu: provide early initialisation hook for IOMMU drivers
Pull ARM updates from Russell King:
"The major updates included in this update are:
- Clang compatible stack pointer accesses by Behan Webster.
- SA11x0 updates from Dmitry Eremin-Solenikov.
- kgdb handling of breakpoints with read-only text/modules
- Support for Privileged-no-execute feature on ARMv7 to prevent
userspace code execution by the kernel.
- AMBA primecell bus handling of irq-safe runtime PM
- Unwinding support for memset/memzero/memmove/memcpy functions
- VFP fixes for Krait CPUs and improvements in detecting the VFP
architecture
- A number of code cleanups (using pr_*, removing or reducing the
severity of a couple of kernel messages, splitting ftrace asm code
out to a separate file, etc.)
- Add machine name to stack dump output"
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (62 commits)
ARM: 8247/2: pcmcia: sa1100: make use of device clock
ARM: 8246/2: pcmcia: sa1111: provide device clock
ARM: 8245/1: pcmcia: soc-common: enable/disable socket clocks
ARM: 8244/1: fbdev: sa1100fb: make use of device clock
ARM: 8243/1: sa1100: add a clock alias for sa1111 pcmcia device
ARM: 8242/1: sa1100: add cpu clock
ARM: 8221/1: PJ4: allow building in Thumb-2 mode
ARM: 8234/1: sa1100: reorder IRQ handling code
ARM: 8233/1: sa1100: switch to hwirq usage
ARM: 8232/1: sa1100: merge GPIO multiplexer IRQ to "normal" irq domain
ARM: 8231/1: sa1100: introduce irqdomains support
ARM: 8230/1: sa1100: shift IRQs by one
ARM: 8229/1: sa1100: replace irq numbers with names in irq driver
ARM: 8228/1: sa1100: drop entry-macro.S
ARM: 8227/1: sa1100: switch to MULTI_IRQ_HANDLER
ARM: 8241/1: Update processor_modes for hyp and monitor mode
ARM: 8240/1: MCPM: document mcpm_sync_init()
ARM: 8239/1: Introduce {set,clear}_pte_bit
ARM: 8238/1: mm: Refine set_memory_* functions
ARM: 8237/1: fix flush_pfn_alias
...
New and updated SoC support, notable changes include:
* bcm: brcmstb SMP support
* bcm: initial iproc/cygnus support
* exynos: Exynos4415 SoC support
* exynos: PMU and suspend support for Exynos5420
* exynos: PMU support for Exynos3250
* exynos: pm related maintenance
* imx: new LS1021A SoC support
* imx: vybrid 610 global timer support
* integrator: convert to using multiplatform configuration
* mediatek: earlyprintk support for mt8127/mt8135
* meson: meson8 soc and l2 cache controller support
* mvebu: Armada 38x CPU hotplug support
* mvebu: drop support for prerelease Armada 375 Z1 stepping
* mvebu: extended suspend support, now works on Armada 370/XP
* omap: hwmod related maintenance
* omap: prcm cleanup
* pxa: initial pxa27x DT handling
* rockchip: SMP support for rk3288
* rockchip: add cpu frequency scaling support
* shmobile: r8a7740 power domain support
* shmobile: various small restart, timer, pci apmu changes
* sunxi: Allwinner A80 (sun9i) earlyprintk support
* ux500: power domain support
Overall, a significant chunk of changes, coming mostly from
the usual suspects: omap, shmobile, samsung and mvebu, all of
which already contain a lot of platform specific code in
arch/arm.
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Merge tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC platform changes from Arnd Bergmann:
"New and updated SoC support, notable changes include:
- bcm:
brcmstb SMP support
initial iproc/cygnus support
- exynos:
Exynos4415 SoC support
PMU and suspend support for Exynos5420
PMU support for Exynos3250
pm related maintenance
- imx:
new LS1021A SoC support
vybrid 610 global timer support
- integrator:
convert to using multiplatform configuration
- mediatek:
earlyprintk support for mt8127/mt8135
- meson:
meson8 soc and l2 cache controller support
- mvebu:
Armada 38x CPU hotplug support
drop support for prerelease Armada 375 Z1 stepping
extended suspend support, now works on Armada 370/XP
- omap:
hwmod related maintenance
prcm cleanup
- pxa:
initial pxa27x DT handling
- rockchip:
SMP support for rk3288
add cpu frequency scaling support
- shmobile:
r8a7740 power domain support
various small restart, timer, pci apmu changes
- sunxi:
Allwinner A80 (sun9i) earlyprintk support
- ux500:
power domain support
Overall, a significant chunk of changes, coming mostly from the usual
suspects: omap, shmobile, samsung and mvebu, all of which already
contain a lot of platform specific code in arch/arm"
* tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (187 commits)
ARM: mvebu: use the cpufreq-dt platform_data for independent clocks
soc: integrator: Add terminating entry for integrator_cm_match
ARM: mvebu: add SDRAM controller description for Armada XP
ARM: mvebu: adjust mbus controller description on Armada 370/XP
ARM: mvebu: add suspend/resume DT information for Armada XP GP
ARM: mvebu: synchronize secondary CPU clocks on resume
ARM: mvebu: make sure MMU is disabled in armada_370_xp_cpu_resume
ARM: mvebu: Armada XP GP specific suspend/resume code
ARM: mvebu: reserve the first 10 KB of each memory bank for suspend/resume
ARM: mvebu: implement suspend/resume support for Armada XP
clk: mvebu: add suspend/resume for gatable clocks
bus: mvebu-mbus: provide a mechanism to save SDRAM window configuration
bus: mvebu-mbus: suspend/resume support
clocksource: time-armada-370-xp: add suspend/resume support
irqchip: armada-370-xp: Add suspend/resume support
ARM: add lolevel debug support for asm9260
ARM: add mach-asm9260
ARM: EXYNOS: use u8 for val[] in struct exynos_pmu_conf
power: reset: imx-snvs-poweroff: add power off driver for i.mx6
ARM: imx: temporarily remove CONFIG_SOC_FSL from LS1021A
...
set_memory_* functions have same implementation
except memory attribute.
This patch makes to use common function for these, and pull out
the functions into arch/arm/mm/pageattr.c like arm64 did.
It will reduce code size and enhance the readability.
Signed-off-by: Jungseung Lee <js07.lee@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
L1_CACHE_BYTES could be larger than real L1 cache line size.
In that case, flush_pfn_alias() would omit to flush last bytes
as much as L1_CACHE_BYTES - real cache line size.
So fix end address to "to + PAGE_SIZE - 1". The bottom bits of the address
is LINELEN. that is ignored by mcrr.
Signed-off-by: Jungseung Lee <js07.lee@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
L1_CACHE_BYTES could be larger value than real L1 cache line size.
In that case, discard_old_kernel_data() would omit to invalidate
last bytes as much as L1_CACHE_BYTES - real cache line size.
So fix end address to "to + PAGE_SIZE -1". The bottom bits
of the address is LINELEN. that is ignored by mcrr.
Signed-off-by: Jungseung Lee <js07.lee@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Modern ARMv7-A/R cores optionally implement below new
hardware feature:
- PXN:
Privileged execute-never(PXN) is a security feature. PXN bit
determines whether the processor can execute software from
the region. This is effective solution against ret2usr attack.
On an implementation that does not include the LPAE, PXN is
optionally supported.
This patch set PXN bit on user page table for preventing
user code execution with privilege mode.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jungseung Lee <js07.lee@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch plumbs the existing ARM IOMMU DMA infrastructure (which isn't
actually called outside of a few drivers) into arch_setup_dma_ops, so
that we can use IOMMUs for DMA transfers in a more generic fashion.
Since this significantly complicates the arch_setup_dma_ops function,
it is moved out of line into dma-mapping.c. If CONFIG_ARM_DMA_USE_IOMMU
is not set, the iommu parameter is ignored and the normal ops are used
instead.
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Pull ARM fixes from Russell King:
"Another round of relatively small ARM fixes.
Thomas spotted that the strex backoff delay bit was a disable bit, so
it needed to be clear for this to work. Vladimir spotted that using a
restart block for the cache flush operation would return -EINTR, which
userspace was not expecting. Dmitry spotted that the auxiliary
control register accesses for Xscale were not correct"
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 8226/1: cacheflush: get rid of restarting block
ARM: 8222/1: mvebu: enable strex backoff delay
ARM: 8216/1: xscale: correct auxiliary register in suspend/resume
Under extremely rare conditions, in an MPCore node consisting of at
least 3 CPUs, two CPUs trying to perform a STREX to data on the same
shared cache line can enter a livelock situation.
This patch enables the HW mechanism that overcomes the bug. This fixes
the incorrect setup of the STREX backoff delay bit due to a wrong
description in the specification.
Note that enabling the STREX backoff delay mechanism is done by
leaving the bit *cleared*, while the bit was currently being set by
the proc-v7.S code.
[Thomas: adapt to latest mainline, slightly reword the commit log, add
stable markers.]
Fixes: de4901933f ("arm: mm: Add support for PJ4B cpu and init routines")
Cc: <stable@vger.kernel.org> # v3.8+
Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
According to the manuals I have, XScale auxiliary register should be
reached with opc_2 = 1 instead of crn = 1. cpu_xscale_proc_init
correctly uses c1, c0, 1 arguments, but cpu_xscale_do_suspend and
cpu_xscale_do_resume use c1, c1, 0. Correct suspend/resume functions to
also use c1, c0, 1.
The issue was primarily noticed thanks to qemu reporing "unsupported
instruction" on the pxa suspend path. Confirmed in PXA210/250 and PXA255
XScale Core manuals and in PXA270 and PXA320 Developers Guides.
Harware tested by me on tosa (pxa255). Robert confirmed on pxa270 board.
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert many (but not all) printk(KERN_* to pr_* to simplify the code.
We take the opportunity to join some printk lines together so we don't
split the message across several lines, and we also add a few levels
to some messages which were previously missing them.
Tested-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than unconditionally allocating a fresh ASID to an mm from an
older generation, attempt to re-use the old assignment where possible.
This can bring performance benefits on systems where the ASID is used to
tag things other than the TLB (e.g. branch prediction resources).
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Certain versions of the Krait processor don't report that they
support the fused multiply accumulate instruction via the MVFR1
register despite the fact that they actually do. Unfortunately we
use this register to identify support for VFPv4. Override the
hwcap on all Krait processors to indicate support for VFPv4 to
workaround this.
Tested-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM fixes from Russell King:
"Two fixes this time, one to ensure that the kuser helper option
depends on MMU as they aren't available for noMMU targets (and if the
option is selected, we end up oopsing.)
The second fix plugs a corner case with the decompressor, ensuring
that the instruction stream can see the relocated code in every case
on ARMv7 CPUs"
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 8198/1: make kuser helpers depend on MMU
ARM: 8191/1: decompressor: ensure I-side picks up relocated code
The kuser helpers page is not set up on non-MMU systems, so it does
not make sense to allow CONFIG_KUSER_HELPERS to be enabled when
CONFIG_MMU=n. Allowing it to be set on !MMU results in an oops in
set_tls (used in execve and the arm_syscall trap handler):
Unhandled exception: IPSR = 00000005 LR = fffffff1
CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216
task: 8b838000 ti: 8b82a000 task.ti: 8b82a000
PC is at flush_thread+0x32/0x40
LR is at flush_thread+0x21/0x40
pc : [<8f00157a>] lr : [<8f001569>] psr: 4100000b
sp : 8b82be20 ip : 00000000 fp : 8b83c000
r10: 00000001 r9 : 88018c84 r8 : 8bb85000
r7 : 8b838000 r6 : 00000000 r5 : 8bb77400 r4 : 8b82a000
r3 : ffff0ff0 r2 : 8b82a000 r1 : 00000000 r0 : 88020354
xPSR: 4100000b
CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216
[<8f002bc1>] (unwind_backtrace) from [<8f002033>] (show_stack+0xb/0xc)
[<8f002033>] (show_stack) from [<8f00265b>] (__invalid_entry+0x4b/0x4c)
As best I can tell this issue existed for the set_tls ARM syscall
before commit fbfb872f5f "ARM: 8148/1: flush TLS and thumbee
register state during exec" consolidated the TLS manipulation code
into the set_tls helper function, but now that we're using it to flush
register state during execve, !MMU users encounter the oops at the
first exec.
Prevent CONFIG_MMU=n configurations from enabling
CONFIG_KUSER_HELPERS.
Fixes: fbfb872f5f (ARM: 8148/1: flush TLS and thumbee register state during exec)
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Reported-by: Stefan Agner <stefan@agner.ch>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 68f3b875f7
"ARM: integrator: make the Integrator multiplatform"
broke allmodconfig like this:
>> arch/arm/include/asm/cmpxchg.h:114:2: error: #error
"SMP is not supported on this platform"
(etc)
This is due to the fact that as we turned on multiplatform
for the Integrator, this enabled a lot of non-applicable
CPU's to be selected for its multiplatform images, due to
a lot of "depends on ARCH_INTEGRATOR" restrictions in
arch/arm/mm/Kconfig for the different ARM CPU types.
Fix this by restricting the CPU selections to respective
multiplatform config, which now becomes a subset of the
possible Integrator configurations, or alternatively the
non-multiplatform config plus ARCH_INTEGRATOR, i.e.:
if (!ARCH_MULTIPLATFORM || ARCH_MULTI_Vx) &&
(ARCH_INTEGRATOR || ARCH_FOO ...)
Since the Integrator has been converted to multiplatform,
this will often take the short form:
if (ARCH_MULTI_Vx && ARCH_INTEGRATOR)
If no other non-multiplatform platforms are elegible.
Reported-by: Build bot for Mark Brown <broonie@kernel.org>
Reported-by: Kbuild test robot <fengguang.wu@intel.com>
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
ARM support for CONFIG_DEBUG_RODATA
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Merge tag 'ronx-next' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into devel-stable
generic fixmaps
ARM support for CONFIG_DEBUG_RODATA
Pull ARM fixes from Russell King:
- add the new bpf syscall to ARM.
- drop a redundant return statement in __iommu_alloc_remap()
- fix a performance issue noticed by Thomas Petazzoni with
kmap_atomic().
- fix an issue with the L2 cache OF parsing code which caused it to
incorrectly print warnings on each boot, and make the warning text
more consistent with the rest of the code
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 8180/1: mm: implement no-highmem fast path in kmap_atomic_pfn()
ARM: 8183/1: l2c: Improve l2c310_of_parse() error message
ARM: 8181/1: Drop extra return statement
ARM: 8182/1: l2c: Make l2x0_cache_size_of_parse() return 'int'
ARM: enable bpf syscall
Since CONFIG_HIGHMEM got enabled on ARMv5 Kirkwood, we have noticed a
very significant drop in networking performance. The test were
conducted on an OpenBlocks A7 board. Without this patch, the outgoing
performance measured with iperf are:
- highmem OFF, TSO OFF 544 Mbit/s
- highmem OFF, TSO ON 942 Mbit/s
- highmem ON, TSO OFF 306 Mbit/s
- highmem ON, TSO ON 246 Mbit/s
On this Kirkwood platform, the L2 cache is a Feroceon cache, and with
this cache, all the range operations have to be done on virtual
addresses and not physical addresses. Therefore, whenever
CONFIG_HIGHMEM is enabled, the cache maintenance operations call
kmap_atomic_pfn() and kunmap_atomic().
However, kmap_atomic_pfn() does not implement the same fast path for
non-highmem pages as the one implemented in kmap_atomic(), and this is
one of the reason for the performance drop. While this patch does not
fully restore the performances, it clearly improves them a lot:
without patch with patch
- highmem ON, TSO OFF 306 Mbit/s 387 Mbit/s
- highmem ON, TSO ON 246 Mbit/s 434 Mbit/s
We're still far from the !CONFIG_HIGHMEM performances, but it does
improve a bit the situation.
Thanks a lot to Ezequiel Garcia and Gregory Clement for all the
testing work around this topic.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Russell King suggested [1]:
"I'd ask for one change. Please make all these messages start with
"L2C-310 OF" not "PL310 OF:". The device is described in ARM
documentation as a L2C-310 not PL310. (Also note the : is dropped
too - most of the other messages don't have the : either.)
The:
"PL310 OF: cache setting yield illegal associativity
PL310 OF: -1073346556 calculated, only 8 and 16 legal"
message could also be changed to something like:
"L2C-310 OF cache associativity %d invalid, only 8 or 16 permittedn"
[1] http://www.spinics.net/lists/arm-kernel/msg372776.html
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 513510ddba
(common: dma-mapping: introduce common remapping functions)
managed to end up with an extra return statement from the
original patch. Drop it.
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since commit f3354ab674 ("ARM: 8169/1: l2c: parse cache properties from
ePAPR definitions") the following error is seen on imx6q:
[ 0.000000] PL310 OF: cache setting yield illegal associativity
[ 0.000000] PL310 OF: -2147097556 calculated, only 8 and 16 legal
As imx6q does not pass the "cache-size" and "cache-sets" properties in DT, the function l2x0_cache_size_of_parse() returns early and keep the 'associativity' pointer uninitialized.
To fix this problem, return error codes inside l2x0_cache_size_of_parse() and only use the 'associativity' pointer result if l2x0_cache_size_of_parse() succeeds.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM fixes from Russell King:
"A couple of ARM fixes.
We fix some printk formats for ptrdiff_t quantities which cause GCC
4.9 to complain, and we also blacklist known buggy GCC 4.8.x compilers
as their miscompilation is serious enough to cause filesystem
corruption, even through many distros have fixed their versions"
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: fix some printk formats
ARM: Blacklist GCC 4.8.0 to GCC 4.8.2 - PR58854
GCC 4.9 complains if we take the difference of two pointers, and it's
printed with "%d". Fix this by using the proper flag - "t" for
ptrdiff_t.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This introduces CONFIG_DEBUG_RODATA, making kernel text and rodata
read-only. Additionally, this splits rodata from text so that rodata can
also be NX, which may lead to wasted memory when aligning to SECTION_SIZE.
The read-only areas are made writable during ftrace updates and kexec.
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Adds CONFIG_ARM_KERNMEM_PERMS to separate the kernel memory regions
into section-sized areas that can have different permisions. Performs
the NX permission changes during free_initmem, so that init memory can be
reclaimed.
This uses section size instead of PMD size to reduce memory lost to
padding on non-LPAE systems.
Based on work by Brad Spengler, Larry Bassel, and Laura Abbott.
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
This is used from set_fixmap() and clear_fixmap() via asm-generic/fixmap.h.
Also makes sure that the fixmap allocation fits into the expected range.
Based on patch by Rabin Vincent.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Rabin Vincent <rabin@rab.in>
Acked-by: Nicolas Pitre <nico@linaro.org>
With commit a05e54c103 ("ARM: 8031/2: change fixmap mapping region to
support 32 CPUs"), the fixmap region was expanded to 2MB, but it
precluded any other uses of the fixmap region. In order to support other
uses the fixmap region needs to be expanded beyond 2MB. Fortunately, the
adjacent 1MB range 0xffe00000-0xfff00000 is availabe.
Remove fixmap_page_table ptr and lookup the page table via the virtual
address so that the fixmap region can span more that one pmd. The 2nd
pmd is already created since it is shared with the vector page.
Signed-off-by: Rob Herring <robh@kernel.org>
[kees: fixed CONFIG_DEBUG_HIGHMEM get_fixmap() calls]
[kees: moved pte allocation outside of CONFIG_HIGHMEM]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
ARM is different from other architectures in that fixmap pages are indexed
with a positive offset from FIXADDR_START. Other architectures index with
a negative offset from FIXADDR_TOP. In order to use the generic fixmap.h
definitions, this patch redefines FIXADDR_TOP to be inclusive of the
useable range. That is, FIXADDR_TOP is the virtual address of the topmost
fixed page. The newly defined FIXADDR_END is the first virtual address
past the fixed mappings.
Signed-off-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
[kees: update for a05e54c103 ("ARM: 8031/2: change fixmap ...")]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Rob Herring <robh@kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
- fix ifdef around cpu_*_do_[suspend, resume] ops to check
CONFIG_ARM_CPU_SUSPEND and not CONFIG_PM_SLEEP
- fix exynos_defconfig build with PM_SLEEP=n and ARM_EXYNOS_CPUIDLE=n
- fix enabling Samsung PM debug functionality due to recently merged
patches and previous merge conflicts
- fix pull-up setting in sd4_width8 pin group for exynos4x12
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Merge tag 'samsung-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into fixes
Merge "Samsung fixes for v3.18" from Kukjin Kim:
- fix ifdef around cpu_*_do_[suspend, resume] ops to check
CONFIG_ARM_CPU_SUSPEND and not CONFIG_PM_SLEEP
- fix exynos_defconfig build with PM_SLEEP=n and ARM_EXYNOS_CPUIDLE=n
- fix enabling Samsung PM debug functionality due to recently merged
patches and previous merge conflicts
- fix pull-up setting in sd4_width8 pin group for exynos4x12
* tag 'samsung-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
ARM: mm: Fix ifdef around cpu_*_do_[suspend, resume] ops
ARM: EXYNOS: Fix build with PM_SLEEP=n and ARM_EXYNOS_CPUIDLE=n
ARM: SAMSUNG: Restore Samsung PM Debug functionality
ARM: dts: Fix pull setting in sd4_width8 pin group for exynos4x12
Signed-off-by: Olof Johansson <olof@lixom.net>
Activate the RCU fast_gup for ARM. We also need to force THP splits to
broadcast an IPI s.t. we block in the fast_gup page walker. As THP
splits are comparatively rare, this should not lead to a noticeable
performance degradation.
Some pre-requisite functions pud_write and pud_page are also added.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
DMA-mapping supports CMA regions places either in low or high memory, so
there is no longer needed to limit default CMA regions only to low memory.
The real limit is still defined by architecture specific DMA limit.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Daniel Drake <drake@endlessm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ARM currently uses a bitmap for tracking atomic allocations. genalloc
already handles this type of memory pool allocation so switch to using
that instead.
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Riley <davidriley@chromium.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Ritesh Harjain <ritesh.harjani@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For architectures without coherent DMA, memory for DMA may need to be
remapped with coherent attributes. Factor out the the remapping code from
arm and put it in a common location to reduce code duplication.
As part of this, the arm APIs are now migrated away from
ioremap_page_range to the common APIs which use map_vm_area for remapping.
This should be an equivalent change and using map_vm_area is more correct
as ioremap_page_range is intended to bring in io addresses into the cpu
space and not regular kernel managed memory.
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Riley <davidriley@chromium.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Ritesh Harjain <ritesh.harjani@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch extends the start and end address of initrd to be page aligned,
so that we can free all memory including the un-page aligned head or tail
page of initrd, if the start or end address of initrd are not page
aligned, the page can't be freed by free_initrd_mem() function.
Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When both 'cache-size' and 'cache-sets' are specified for a L2 cache
controller node, parse those properties and set up the
set size based on which type of L2 cache controller we are using.
Update the L2 cache controller Device Tree binding with the optional
'cache-size', 'cache-sets', 'cache-block-size' and 'cache-line-size'
properties. These come from the ePAPR specification.
Using the cache size, number of sets and cache line size we can
calculate desired associativity of the L2 cache. This is done
by the calculation:
set size = cache size / sets
ways = set size / line size
way size = cache size / ways = sets * line size
associativity = cache size / way size
Example output from the PB1176 DT that look like this:
L2: l2-cache {
compatible = "arm,l220-cache";
(...)
arm,override-auxreg;
cache-size = <131072>; // 128kB
cache-sets = <512>;
cache-line-size = <32>;
};
Ends up like this:
L2C OF: override cache size: 131072 bytes (128KB)
L2C OF: override line size: 32 bytes
L2C OF: override way size: 16384 bytes (16KB)
L2C OF: override associativity: 8
L2C: DT/platform modifies aux control register: 0x02020fff -> 0x02030fff
L2C-220 cache controller enabled, 8 ways, 128 kB
L2C-220: CACHE_ID 0x41000486, AUX_CTRL 0x06030fff
Which is consistent with the value earlier hardcoded for the
PB1176 platform.
This patch is an extended version based on the initial patch
by Florian Fainelli.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use the more common pr_warn.
Other miscellanea:
o Coalesce formats
o Realign arguments
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The alignment fixup incorrectly decodes faulting ARM VLDn/VSTn
instructions (where the optional alignment hint is given but incorrect)
as LDR/STR, leading to register corruption. Detect these and correctly
treat them as unhandled, so that userspace gets the fault it expects.
Reported-by: Simon Hosie <simon.hosie@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
SCTLR.HA (hardware access flag) is deprecated and not actually
implemented by any CPUs. Furthermore, it can confuse cr_alignment checks
where the whole value of SCTLR is compared against the value sitting in
the hardware, since the bit is actually RAZ/WI and will not match the
saved cr_alignment value.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
