Commit f1b36dcb5c ("arm64: pmuv3: handle !PMUv3 when probing") is
a little too restrictive, and prevents the use of of backwards
compatible PMUv3 extenstions, which have a PMUver value other than 1.
For instance, ARMv8.1 PMU extensions (as implemented by ThunderX2) are
reported with PMUver value 4.
Per the usual ID register principles, at least 0x1-0x7 imply a
PMUv3-compatible PMU. It's not currently clear whether 0x8-0xe imply the
same.
For the time being, treat the value as signed, and with 0x1-0x7 treated
as meaning PMUv3 is implemented. This may be relaxed by future patches.
Reported-by: Jayachandran C <jnair@caviumnetworks.com>
Tested-by: Jayachandran C <jnair@caviumnetworks.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We now trap accesses to CNTVCT_EL0 when the counter is broken
enough to require the kernel to mediate the access. But it
turns out that some existing userspace (such as OpenMPI) do
probe for the counter frequency, leading to an UNDEF exception
as CNTVCT_EL0 and CNTFRQ_EL0 share the same control bit.
The fix is to handle the exception the same way we do for CNTVCT_EL0.
Fixes: a86bd139f2 ("arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabled")
Reported-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Since bbb56c2722 ("arm64: Add detection code for broken .inst support
in binutils"), running any make target that doesn't involve the cross
compiler results in a spurious warning:
$ make ARCH=arm64 menuconfig
arch/arm64/Makefile:43: Detected assembler with broken .inst; disassembly will be unreliable
while
$ make ARCH=arm64 CROSS_COMPILE=aarch64-arm-linux- menuconfig
is silent (assuming your compiler is not affected). That's because
the code that tests for the workaround is always run, irrespective
of the current configuration being available or not.
An easy fix is to make the detection conditional on CONFIG_ARM64
being defined, which is only the case when actually building
something.
Fixes: bbb56c2722 ("arm64: Add detection code for broken .inst support in binutils")
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Now that we have a framework to handle the ACPI bits, make the PMUv3
code use this. The framework is a little different to what was
originally envisaged, and we can drop some unused support code in the
process of moving over to it.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
[will: make armv8_pmu_driver_init static]
Signed-off-by: Will Deacon <will.deacon@arm.com>
When probing via ACPI, we won't know up-front whether a CPU has a PMUv3
compatible PMU. Thus we need to consult ID registers during probe time.
This patch updates our PMUv3 probing code to test for the presence of
PMUv3 functionality before touching an PMUv3-specific registers, and
before updating the struct arm_pmu with PMUv3 data.
When a PMUv3-compatible PMU is not present, probing will return -ENODEV.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Currently the ACPI parking protocol code needs to parse each CPU's MADT
GICC table to extract the mailbox address and so on. Each time we parse
a GICC table, we call back to the parking protocol code to parse it.
This has been fine so far, but we're about to have more code that needs
to extract data from the GICC tables, and adding a callback for each
user is going to get unwieldy.
Instead, this patch ensures that we stash a copy of each CPU's GICC
table at boot time, such that anything needing to parse it can later
request it. This will allow for other parsers of GICC, and for
simplification to the ACPI parking protocol code. Note that we must
store a copy, rather than a pointer, since the core ACPI code
temporarily maps/unmaps tables while iterating over them.
Since we parse the MADT before we know how many CPUs we have (and hence
before we setup the percpu areas), we must use an NR_CPUS sized array.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
- Allow checking of a CPU-local erratum
- Add CNTVCT_EL0 trap handler
- Define Cortex-A73 MIDR
- Allow an erratum to be match for all revisions of a core
- Add capability to advertise Cortex-A73 erratum 858921
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Merge tag 'arch-timer-errata-prereq' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into for-next/core
Pre-requisites for the arch timer errata workarounds:
- Allow checking of a CPU-local erratum
- Add CNTVCT_EL0 trap handler
- Define Cortex-A73 MIDR
- Allow an erratum to be match for all revisions of a core
- Add capability to advertise Cortex-A73 erratum 858921
* tag 'arch-timer-errata-prereq' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms:
arm64: cpu_errata: Add capability to advertise Cortex-A73 erratum 858921
arm64: cpu_errata: Allow an erratum to be match for all revisions of a core
arm64: Define Cortex-A73 MIDR
arm64: Add CNTVCT_EL0 trap handler
arm64: Allow checking of a CPU-local erratum
In order to work around Cortex-A73 erratum 858921 in a subsequent
patch, add the required capability that advertise the erratum.
As the configuration option it depends on is not present yet,
this has no immediate effect.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Some minor erratum may not be fixed in further revisions of a core,
leading to a situation where the workaround needs to be updated each
time an updated core is released.
Introduce a MIDR_ALL_VERSIONS match helper that will work for all
versions of that MIDR, once and for all.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
As we're about to introduce a new workaround that is specific to
Cortex-A73, let's define the coresponding MIDR.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Since people seem to make a point in breaking the userspace visible
counter, we have no choice but to trap the access. Add the required
handler.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
this_cpu_has_cap() only checks the feature array, and not the errata
one. In order to be able to check for a CPU-local erratum, allow it
to inspect the latter as well.
This is consistent with cpus_have_cap()'s behaviour, which includes
errata already.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
If a page is marked read only we should print out that fact,
instead of printing out that there was a page fault. Right now we
get a cryptic error message that something went wrong with an
unhandled fault, but we don't evaluate the esr to figure out that
it was a read/write permission fault.
Instead of seeing:
Unable to handle kernel paging request at virtual address ffff000008e460d8
pgd = ffff800003504000
[ffff000008e460d8] *pgd=0000000083473003, *pud=0000000083503003, *pmd=0000000000000000
Internal error: Oops: 9600004f [#1] PREEMPT SMP
we'll see:
Unable to handle kernel write to read-only memory at virtual address ffff000008e760d8
pgd = ffff80003d3de000
[ffff000008e760d8] *pgd=0000000083472003, *pud=0000000083435003, *pmd=0000000000000000
Internal error: Oops: 9600004f [#1] PREEMPT SMP
We also add a userspace address check into is_permission_fault()
so that the function doesn't return true for ttbr0 PAN faults
when it shouldn't.
Reviewed-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Acked-by: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Kdump is enabled by default as kexec is.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Arch-specific functions are added to allow for implementing a crash dump
file interface, /proc/vmcore, which can be viewed as a ELF file.
A user space tool, like kexec-tools, is responsible for allocating
a separate region for the core's ELF header within crash kdump kernel
memory and filling it in when executing kexec_load().
Then, its location will be advertised to crash dump kernel via a new
device-tree property, "linux,elfcorehdr", and crash dump kernel preserves
the region for later use with reserve_elfcorehdr() at boot time.
On crash dump kernel, /proc/vmcore will access the primary kernel's memory
with copy_oldmem_page(), which feeds the data page-by-page by ioremap'ing
it since it does not reside in linear mapping on crash dump kernel.
Meanwhile, elfcorehdr_read() is simple as the region is always mapped.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In addition to common VMCOREINFO's defined in
crash_save_vmcoreinfo_init(), we need to know, for crash utility,
- kimage_voffset
- PHYS_OFFSET
to examine the contents of a dump file (/proc/vmcore) correctly
due to the introduction of KASLR (CONFIG_RANDOMIZE_BASE) in v4.6.
- VA_BITS
is also required for makedumpfile command.
arch_crash_save_vmcoreinfo() appends them to the dump file.
More VMCOREINFO's may be added later.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Primary kernel calls machine_crash_shutdown() to shut down non-boot cpus
and save registers' status in per-cpu ELF notes before starting crash
dump kernel. See kernel_kexec().
Even if not all secondary cpus have shut down, we do kdump anyway.
As we don't have to make non-boot(crashed) cpus offline (to preserve
correct status of cpus at crash dump) before shutting down, this patch
also adds a variant of smp_send_stop().
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Since arch_kexec_protect_crashkres() removes a mapping for crash dump
kernel image, the loaded data won't be preserved around hibernation.
In this patch, helper functions, crash_prepare_suspend()/
crash_post_resume(), are additionally called before/after hibernation so
that the relevant memory segments will be mapped again and preserved just
as the others are.
In addition, to minimize the size of hibernation image, crash_is_nosave()
is added to pfn_is_nosave() in order to recognize only the pages that hold
loaded crash dump kernel image as saveable. Hibernation excludes any pages
that are marked as Reserved and yet "nosave."
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch_kexec_protect_crashkres() and arch_kexec_unprotect_crashkres()
are meant to be called by kexec_load() in order to protect the memory
allocated for crash dump kernel once the image is loaded.
The protection is implemented by unmapping the relevant segments in crash
dump kernel memory, rather than making it read-only as other archs do,
to prevent coherency issues due to potential cache aliasing (with
mismatched attributes).
Page-level mappings are consistently used here so that we can change
the attributes of segments in page granularity as well as shrink the region
also in page granularity through /sys/kernel/kexec_crash_size, putting
the freed memory back to buddy system.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This function validates and invalidates PTE entries, and will be utilized
in kdump to protect loaded crash dump kernel image.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
"crashkernel=" kernel parameter specifies the size (and optionally
the start address) of the system ram to be used by crash dump kernel.
reserve_crashkernel() will allocate and reserve that memory at boot time
of primary kernel.
The memory range will be exposed to userspace as a resource named
"Crash kernel" in /proc/iomem.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Pratyush Anand <panand@redhat.com>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Crash dump kernel uses only a limited range of available memory as System
RAM. On arm64 kdump, This memory range is advertised to crash dump kernel
via a device-tree property under /chosen,
linux,usable-memory-range = <BASE SIZE>
Crash dump kernel reads this property at boot time and calls
memblock_cap_memory_range() to limit usable memory which are listed either
in UEFI memory map table or "memory" nodes of a device tree blob.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Geoff Levand <geoff@infradead.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
To prevent unintended modifications to the kernel text (malicious or
otherwise) while running the EFI stub, describe the kernel image as
two separate sections: a .text section with read-execute permissions,
covering .text, .rodata and .init.text, and a .data section with
read-write permissions, covering .init.data, .data and .bss.
This relies on the firmware to actually take the section permission
flags into account, but this is something that is currently being
implemented in EDK2, which means we will likely start seeing it in
the wild between one and two years from now.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Replace open coded constants with symbolic ones throughout the
Image and the EFI headers. No binary level changes are intended.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The kernel's EFI PE/COFF header contains a dummy .reloc section, and
an explanatory comment that claims that this is required for the EFI
application loader to accept the Image as a relocatable image (i.e.,
one that can be loaded at any offset and fixed up in place)
This was inherited from the x86 implementation, which has elaborate host
tooling to mangle the PE/COFF header post-link time, and which populates
the .reloc section with a single dummy base relocation. On ARM, no such
tooling exists, and the .reloc section remains empty, and is never even
exposed via the BaseRelocationTable directory entry, which is where the
PE/COFF loader looks for it.
The PE/COFF spec is unclear about relocatable images that do not require
any fixups, but the EDK2 implementation, which is the de facto reference
for PE/COFF in the UEFI space, clearly does not care, and explicitly
mentions (in a comment) that relocatable images with no base relocations
are perfectly fine, as long as they don't have the RELOCS_STRIPPED
attribute set (which is not the case for our PE/COFF image)
So simply remove the .reloc section altogether.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Bring the PE/COFF header in line with the PE/COFF spec, by setting
NumberOfSymbols to 0, and removing the section alignment flags.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
After having split off the PE header, clean up the bits that remain:
use .long consistently, merge two adjacent #ifdef CONFIG_EFI blocks,
fix the offset of the PE header pointer and remove the redundant .align
that follows it.
Also, since we will be eliminating all open coded constants from the
EFI header in subsequent patches, let's replace the open coded "ARM\x64"
magic number with its .ascii equivalent.
No changes to the resulting binary image are intended.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In preparation of yet another round of modifications to the PE/COFF
header, macroize it and move the definition into a separate source
file.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
read_system_reg() can readily be confused with read_sysreg(),
whereas these are really quite different in their meaning.
This patches attempts to reduce the ambiguity be reserving "sysreg"
for the actual system register accessors.
read_system_reg() is instead renamed to read_sanitised_ftr_reg(),
to make it more obvious that the Linux-defined sanitised feature
register cache is being accessed here, not the underlying
architectural system registers.
cpufeature.c's internal __raw_read_system_reg() function is renamed
in line with its actual purpose: a form of read_sysreg() that
indexes on (non-compiletime-constant) encoding rather than symbolic
register name.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
There are two unnecessary newlines, one is in show_regs, another
is in __show_regs(), drop them.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This is the third attempt at enabling the use of contiguous hints for
kernel mappings. The most recent attempt 0bfc445dec was reverted after
it turned out that updating permission attributes on live contiguous ranges
may result in TLB conflicts. So this time, the contiguous hint is not set
for .rodata or for the linear alias of .text/.rodata, both of which are
mapped read-write initially, and remapped read-only at a later stage.
(Note that the latter region could also be unmapped and remapped again
with updated permission attributes, given that the region, while live, is
only mapped for the convenience of the hibernation code, but that also
means the TLB footprint is negligible anyway, so why bother)
This enables the following contiguous range sizes for the virtual mapping
of the kernel image, and for the linear mapping:
granule size | cont PTE | cont PMD |
-------------+------------+------------+
4 KB | 64 KB | 32 MB |
16 KB | 2 MB | 1 GB* |
64 KB | 2 MB | 16 GB* |
* Only when built for 3 or more levels of translation. This is due to the
fact that a 2 level configuration only consists of PGDs and PTEs, and the
added complexity of dealing with folded PMDs is not justified considering
that 16 GB contiguous ranges are likely to be ignored by the hardware (and
16k/2 levels is a niche configuration)
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The routines __pud_populate and __pmd_populate only create a table
entry at their respective level which refers to the next level page
by its physical address, so there is no reason to map this page and
then unmap it immediately after.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In preparation of extending the policy for manipulating kernel mappings
with whether or not contiguous hints may be used in the page tables,
replace the bool 'page_mappings_only' with a flags field and a flag
NO_BLOCK_MAPPINGS.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
A mapping with the contiguous bit cannot be safely manipulated while
live, regardless of whether the bit changes between the old and new
mapping. So take this into account when deciding whether the change
is safe.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The debug_pagealloc facility manipulates kernel mappings in the linear
region at page granularity to detect out of bounds or use-after-free
accesses. Since the kernel segments are not allocated dynamically,
there is no point in taking the debug_pagealloc_enabled flag into
account for them, and we can use block mappings unconditionally.
Note that this applies equally to the linear alias of text/rodata:
we will never have dynamic allocations there given that the same
memory is statically in use by the kernel image.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Align the function prototype of alloc_init_pte() with its pmd and pud
counterparts by replacing the pfn parameter with the equivalent physical
address.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
To avoid having mappings that are writable and executable at the same
time, split the init region into a .init.text region that is mapped
read-only, and a .init.data region that is mapped non-executable.
This is possible now that the alternative patching occurs via the linear
mapping, and the linear alias of the init region is always mapped writable
(but never executable).
Since the alternatives descriptions themselves are read-only data, move
those into the .init.text region.
Reviewed-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Now that alternatives patching code no longer relies on the primary
mapping of .text being writable, we can remove the code that removes
the writable permissions post-init time, and map it read-only from
the outset.
To preserve the existing behavior under rodata=off, which is relied
upon by external debuggers to manage software breakpoints (as pointed
out by Mark), add an early_param() check for rodata=, and use RWX
permissions if it set to 'off'.
Reviewed-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
One important rule of thumb when desiging a secure software system is
that memory should never be writable and executable at the same time.
We mostly adhere to this rule in the kernel, except at boot time, when
regions may be mapped RWX until after we are done applying alternatives
or making other one-off changes.
For the alternative patching, we can improve the situation by applying
the fixups via the linear mapping, which is never mapped with executable
permissions. So map the linear alias of .text with RW- permissions
initially, and remove the write permissions as soon as alternative
patching has completed.
Reviewed-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In preparation of refactoring the kernel mapping logic so that text regions
are never mapped writable, which would require adding explicit TLB
maintenance to new call sites of create_mapping_late() (which is currently
invoked twice from the same function), move the TLB maintenance from the
call site into create_mapping_late() itself, and change it from a full
TLB flush into a flush by VA, which is more appropriate here.
Also, given that create_mapping_late() has evolved into a routine that only
updates protection bits on existing mappings, rename it to
update_mapping_prot()
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This reverts commit 9c0e83c371, which
is no longer needed now that the modversions code plays nice with
relocatable PIE kernels.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We only need to initialise sctlr_el1 if we're installing an EL2 stub, so
we may as well defer this until we're doing so. Similarly, we can defer
intialising CPTR_EL2 until then, as we do not access any trapped
functionality as part of el2_setup.
This patch modified el2_setup accordingly, allowing us to remove a
branch and simplify the code flow.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The early el2_setup code is a little convoluted, with two branches where
one would do. This makes the code more painful to read than is
necessary.
We can remove a branch and simplify the logic by moving the early return
in the booted-at-EL1 case earlier in the function. This separates it
from all the setup logic that only makes sense for EL2.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Check if CONFIG_HAVE_HW_BREAKPOINT is enabled before compiling in extra
data required for hardware breakpoints. Compiling out this code when hw
breakpoints are disabled saves about 272 bytes per struct task_struct.
Signed-off-by: Chris Redmon <credmonster@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add support for allocating physically contiguous DMA buffers on arm64
systems with an IOMMU. This can be useful when two or more devices
with different memory requirements are involved in buffer sharing.
Note that as this uses the CMA allocator, setting the
DMA_ATTR_FORCE_CONTIGUOUS attribute has a runtime-dependency on
CONFIG_DMA_CMA, just like on arm32.
For arm64 systems using swiotlb, no changes are needed to support the
allocation of physically contiguous DMA buffers:
- swiotlb always uses physically contiguous buffers (up to
IO_TLB_SEGSIZE = 128 pages),
- arm64's __dma_alloc_coherent() already calls
dma_alloc_from_contiguous() when CMA is available.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This mirrors commit e9c38ceba8 ("ARM: 8455/1: define __BUG as
asm(BUG_INSTR) without CONFIG_BUG") to make the behavior of
arm64 consistent with arm and x86, and avoids lots of warnings in
randconfig builds, such as:
kernel/seccomp.c: In function '__seccomp_filter':
kernel/seccomp.c:666:1: error: no return statement in function returning non-void [-Werror=return-type]
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
ARMv8.3 adds new instructions to support Release Consistent
processor consistent (RCpc) model, which is weaker than the
RCsc model.
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Mark Rutland