2216 Commits

Author SHA1 Message Date
Suzuki K Poulose
ce00e3cb4f arm64: Add a helper for PARange to physical shift conversion
On arm64, ID_AA64MMFR0_EL1.PARange encodes the maximum Physical
Address range supported by the CPU. Add a helper to decode this
to actual physical shift. If we hit an unallocated value, return
the maximum range supported by the kernel.
This will be used by KVM to set the VTCR_EL2.T0SZ, as it
is about to move its place. Having this helper keeps the code
movement cleaner.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Christoffer Dall <cdall@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-10-01 13:50:15 +01:00
Marc Zyngier
95b861a4a6 arm64: arch_timer: Add workaround for ARM erratum 1188873
When running on Cortex-A76, a timer access from an AArch32 EL0
task may end up with a corrupted value or register. The workaround for
this is to trap these accesses at EL1/EL2 and execute them there.

This only affects versions r0p0, r1p0 and r2p0 of the CPU.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:38:47 +01:00
Marc Zyngier
32a3e635fb arm64: compat: Add CNTFRQ trap handler
Just like CNTVCT, we need to handle userspace trapping into the
kernel if we're decided that the timer wasn't fit for purpose...
64bit userspace is already dealt with, but we're missing the
equivalent compat handling.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:36:03 +01:00
Marc Zyngier
50de013d22 arm64: compat: Add CNTVCT trap handler
Since people seem to make a point in breaking the userspace visible
counter, we have no choice but to trap the access. We already do this
for 64bit userspace, but this is lacking for compat. Let's provide
the required handler.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:36:01 +01:00
Marc Zyngier
bd7ac140b8 arm64: Add decoding macros for CP15_32 and CP15_64 traps
So far, we don't have anything to help decoding ESR_ELx when dealing
with ESR_ELx_EC_CP15_{32,64}. As we're about to handle some of those,
let's add some useful macros.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:35:50 +01:00
Suzuki K Poulose
9f98ddd668 kvm: arm64: Add helper for loading the stage2 setting for a VM
We load the stage2 context of a guest for different operations,
including running the guest and tlb maintenance on behalf of the
guest. As of now only the vttbr is private to the guest, but this
is about to change with IPA per VM. Add a helper to load the stage2
configuration for a VM, which could do the right thing with the
future changes.

Cc: Christoffer Dall <cdall@kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-10-01 13:08:41 +01:00
Ard Biesheuvel
9376b1e7b6 arm64: remove unused asm/compiler.h header file
arm64 does not define CONFIG_HAVE_ARCH_COMPILER_H, nor does it keep
anything useful in its copy of asm/compiler.h, so let's remove it
before anybody starts using it.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 11:57:04 +01:00
Will Deacon
24951465cb arm64: compat: Provide definition for COMPAT_SIGMINSTKSZ
arch/arm/ defines a SIGMINSTKSZ of 2k, so we should use the same value
for compat tasks.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reported-by: Steve McIntyre <steve.mcintyre@arm.com>
Tested-by: Steve McIntyre <93sam@debian.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 11:44:02 +01:00
Eric W. Biederman
f3a900b341 signal/arm64: Add and use arm64_force_sig_ptrace_errno_trap
Add arm64_force_sig_ptrace_errno_trap for consistency with
arm64_force_sig_fault and use it where appropriate.

This adds the show_signal logic to the force_sig_errno_trap case,
where it was apparently overlooked earlier.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:55:15 +02:00
Eric W. Biederman
009f608ab2 signal/arm64: Remove arm64_force_sig_info
The function has no more callers so remove it.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:55:00 +02:00
Eric W. Biederman
b4d5557caa signal/arm64: Add and use arm64_force_sig_mceerr as appropriate
Add arm64_force_sig_mceerr for consistency with arm64_force_sig_fault,
and use it in the one location that can take advantage of it.

This removes the fiddly filling out of siginfo before sending a signal
reporting an memory error to userspace.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:54:51 +02:00
Eric W. Biederman
feca355b3d signal/arm64: Add and use arm64_force_sig_fault where appropriate
Wrap force_sig_fault with a helper that calls arm64_show_signal
and call arm64_force_sig_fault where appropraite.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2018-09-27 21:54:43 +02:00
Eric W. Biederman
24b8f79dd8 signal/arm64: Remove unneeded tsk parameter from arm64_force_sig_info
Every caller passes in current for tsk so there is no need to pass
tsk.  Instead make tsk a local variable initialized to current.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:53:35 +02:00
Eric W. Biederman
6fa998e83e signal/arm64: Push siginfo generation into arm64_notify_die
Instead of generating a struct siginfo before calling arm64_notify_die
pass the signal number, tne sicode and the fault address into
arm64_notify_die and have it call force_sig_fault instead of
force_sig_info to let the generic code generate the struct siginfo.

This keeps code passing just the needed information into
siginfo generating code, making it easier to see what
is happening and harder to get wrong.  Further by letting
the generic code handle the generation of struct siginfo
it reduces the number of sites generating struct siginfo
making it possible to review them and verify that all
of the fiddly details for a structure passed to userspace
are handled properly.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:52:54 +02:00
Ard Biesheuvel
c296146c05 arm64/kernel: jump_label: Switch to relative references
On a randomly chosen distro kernel build for arm64, vmlinux.o shows the
following sections, containing jump label entries, and the associated
RELA relocation records, respectively:

  ...
  [38088] __jump_table      PROGBITS         0000000000000000  00e19f30
       000000000002ea10  0000000000000000  WA       0     0     8
  [38089] .rela__jump_table RELA             0000000000000000  01fd8bb0
       000000000008be30  0000000000000018   I      38178   38088     8
  ...

In other words, we have 190 KB worth of 'struct jump_entry' instances,
and 573 KB worth of RELA entries to relocate each entry's code, target
and key members. This means the RELA section occupies 10% of the .init
segment, and the two sections combined represent 5% of vmlinux's entire
memory footprint.

So let's switch from 64-bit absolute references to 32-bit relative
references for the code and target field, and a 64-bit relative
reference for the 'key' field (which may reside in another module or the
core kernel, which may be more than 4 GB way on arm64 when running with
KASLR enable): this reduces the size of the __jump_table by 33%, and
gets rid of the RELA section entirely.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Link: https://lkml.kernel.org/r/20180919065144.25010-4-ard.biesheuvel@linaro.org
2018-09-27 17:56:47 +02:00
Christoph Hellwig
3cfa210bf3 xen: don't include <xen/xen.h> from <asm/io.h> and <asm/dma-mapping.h>
Nothing Xen specific in these headers, which get included from a lot
of code in the kernel.  So prune the includes and move them to the
Xen-specific files that actually use them instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-26 08:45:18 -06:00
Christoph Hellwig
c39ae60dfb block: remove ARCH_BIOVEC_PHYS_MERGEABLE
Take the Xen check into the core code instead of delegating it to
the architectures.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-26 08:45:11 -06:00
Christoph Hellwig
20e3267601 xen: provide a prototype for xen_biovec_phys_mergeable in xen.h
Having multiple externs in arch headers is not a good way to provide
a common interface.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-26 08:45:10 -06:00
Christoph Hellwig
1a0afc14b5 Revert "dma-mapping: clear dev->dma_ops in arch_teardown_dma_ops"
This reverts commit 46053c73685411915d3de50c5a0045beef32806b.

This change breaks architectures setting up dma_ops in their own magic
way and not using arch_setup_dma_ops, so revert it.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-09-25 15:12:26 -07:00
Nathan Chancellor
b5bb425871 arm64: percpu: Initialize ret in the default case
Clang warns that if the default case is taken, ret will be
uninitialized.

./arch/arm64/include/asm/percpu.h:196:2: warning: variable 'ret' is used
uninitialized whenever switch default is taken
[-Wsometimes-uninitialized]
        default:
        ^~~~~~~
./arch/arm64/include/asm/percpu.h:200:9: note: uninitialized use occurs
here
        return ret;
               ^~~
./arch/arm64/include/asm/percpu.h:157:19: note: initialize the variable
'ret' to silence this warning
        unsigned long ret, loop;
                         ^
                          = 0

This warning appears several times while building the erofs filesystem.
While it's not strictly wrong, the BUILD_BUG will prevent this from
becoming a true problem. Initialize ret to 0 in the default case right
before the BUILD_BUG to silence all of these warnings.

Reported-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
2018-09-25 13:26:48 -07:00
Jun Yao
2330b7ca78 arm64/mm: use fixmap to modify swapper_pg_dir
Once swapper_pg_dir is in the rodata section, it will not be possible to
modify it directly, but we will need to modify it in some cases.

To enable this, we can use the fixmap when deliberately modifying
swapper_pg_dir. As the pgd is only transiently mapped, this provides
some resilience against illicit modification of the pgd, e.g. for
Kernel Space Mirror Attack (KSMA).

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: simplify ifdeffery, commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25 15:10:55 +01:00
Jun Yao
2b5548b681 arm64/mm: Separate boot-time page tables from swapper_pg_dir
Since the address of swapper_pg_dir is fixed for a given kernel image,
it is an attractive target for manipulation via an arbitrary write. To
mitigate this we'd like to make it read-only by moving it into the
rodata section.

We require that swapper_pg_dir is at a fixed offset from tramp_pg_dir
and reserved_ttbr0, so these will also need to move into rodata.
However, swapper_pg_dir is allocated along with some transient page
tables used for boot which we do not want to move into rodata.

As a step towards this, this patch separates the boot-time page tables
into a new init_pg_dir, and reduces swapper_pg_dir to the single page it
needs to be. This allows us to retain the relationship between
swapper_pg_dir, tramp_pg_dir, and swapper_pg_dir, while cleanly
separating these from the boot-time page tables.

The init_pg_dir holds all of the pgd/pud/pmd/pte levels needed during
boot, and all of these levels will be freed when we switch to the
swapper_pg_dir, which is initialized by the existing code in
paging_init(). Since we start off on the init_pg_dir, we no longer need
to allocate a transient page table in paging_init() in order to ensure
that swapper_pg_dir isn't live while we initialize it.

There should be no functional change as a result of this patch.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: place init_pg_dir after BSS, fold mm changes, commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25 15:10:54 +01:00
Christoph Hellwig
6a9f5f240a block: simplify BIOVEC_PHYS_MERGEABLE
Turn the macro into an inline, move it to blk.h and simplify the
arch hooks a bit.

Also rename the function to biovec_phys_mergeable as there is no need
to shout.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-24 12:33:54 -06:00
James Morse
8a695a5873 arm64: Kconfig: Remove ARCH_HAS_HOLES_MEMORYMODEL
include/linux/mmzone.h describes ARCH_HAS_HOLES_MEMORYMODEL as
relevant when parts the memmap have been free()d. This would
happen on systems where memory is smaller than a sparsemem-section,
and the extra struct pages are expensive. pfn_valid() on these
systems returns true for the whole sparsemem-section, so an extra
memmap_valid_within() check is needed.

On arm64 we have nomap memory, so always provide pfn_valid() to test
for nomap pages. This means ARCH_HAS_HOLES_MEMORYMODEL's extra checks
are already rolled up into pfn_valid().

Remove it.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-21 12:02:45 +01:00
Anshuman Khandual
21f8479617 arm64/cpufeatures: Emulate MRS instructions by parsing ESR_ELx.ISS
Armv8.4-A extension enables MRS instruction encodings inside ESR_ELx.ISS
during exception class ESR_ELx_EC_SYS64 (0x18). This encoding can be used
to emulate MRS instructions which can avoid fetch/decode from user space
thus improving performance. This adds a new sys64_hook structure element
with applicable ESR mask/value pair for MRS instructions on various system
registers but constrained by sysreg encodings which is currently allowed
to be emulated.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-21 11:06:18 +01:00
Anshuman Khandual
520ad98871 arm64/cpufeatures: Factorize emulate_mrs()
MRS emulation gets triggered with exception class (0x00 or 0x18) eventually
calling the function emulate_mrs() which fetches the user space instruction
and analyses it's encodings (OP0, OP1, OP2, CRN, CRM, RT). The kernel tries
to emulate the given instruction looking into the encoding details. Going
forward these encodings can also be parsed from ESR_ELx.ISS fields without
requiring to fetch/decode faulting userspace instruction which can improve
performance. This factorizes emulate_mrs() function in a way that it can be
called directly with MRS encodings (OP0, OP1, OP2, CRN, CRM) for any given
target register which can then be used directly from 0x18 exception class.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-21 11:05:58 +01:00
Anshuman Khandual
1c8391412d arm64/cpufeatures: Introduce ESR_ELx_SYS64_ISS_RT()
Extracting target register from ESR.ISS encoding has already been required
at multiple instances. Just make it a macro definition and replace all the
existing use cases.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-21 11:05:25 +01:00
Will Deacon
880f7cc472 arm64: cpu_errata: Remove ARM64_MISMATCHED_CACHE_LINE_SIZE
There's no need to treat mismatched cache-line sizes reported by CTR_EL0
differently to any other mismatched fields that we treat as "STRICT" in
the cpufeature code. In both cases we need to trap and emulate EL0
accesses to the register, so drop ARM64_MISMATCHED_CACHE_LINE_SIZE and
rely on ARM64_MISMATCHED_CACHE_TYPE instead.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: move ARM64_HAS_CNP in the empty cpucaps.h slot]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-19 18:21:49 +01:00
Vladimir Murzin
ab510027dc arm64: KVM: Enable Common Not Private translations
We rely on cpufeature framework to detect and enable CNP so for KVM we
need to patch hyp to set CNP bit just before TTBR0_EL2 gets written.

For the guest we encode CNP bit while building vttbr, so we don't need
to bother with that in a world switch.

Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-18 12:03:34 +01:00
Vladimir Murzin
5ffdfaedfa arm64: mm: Support Common Not Private translations
Common Not Private (CNP) is a feature of ARMv8.2 extension which
allows translation table entries to be shared between different PEs in
the same inner shareable domain, so the hardware can use this fact to
optimise the caching of such entries in the TLB.

CNP occupies one bit in TTBRx_ELy and VTTBR_EL2, which advertises to
the hardware that the translation table entries pointed to by this
TTBR are the same as every PE in the same inner shareable domain for
which the equivalent TTBR also has CNP bit set. In case CNP bit is set
but TTBR does not point at the same translation table entries for a
given ASID and VMID, then the system is mis-configured, so the results
of translations are UNPREDICTABLE.

For kernel we postpone setting CNP till all cpus are up and rely on
cpufeature framework to 1) patch the code which is sensitive to CNP
and 2) update TTBR1_EL1 with CNP bit set. TTBR1_EL1 can be
reprogrammed as result of hibernation or cpuidle (via __enable_mmu).
For these two cases we restore CnP bit via __cpu_suspend_exit().

There are a few cases we need to care of changes in TTBR0_EL1:
  - a switch to idmap
  - software emulated PAN

we rule out latter via Kconfig options and for the former we make
sure that CNP is set for non-zero ASIDs only.

Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
[catalin.marinas@arm.com: default y for CONFIG_ARM64_CNP]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-18 12:02:27 +01:00
Suzuki K Poulose
74e248286e arm64: sysreg: Clean up instructions for modifying PSTATE fields
Instructions for modifying the PSTATE fields which were not supported
in the older toolchains (e.g, PAN, UAO) are generated using macros.
We have so far used the normal sys_reg() helper for defining the PSTATE
fields. While this works fine, it is really difficult to correlate the
code with the Arm ARM definition.

As per Arm ARM, the PSTATE fields are defined only using Op1, Op2 fields,
with fixed values for Op0, CRn. Also the CRm field has been reserved
for the Immediate value for the instruction. So using the sys_reg()
looks quite confusing.

This patch cleans up the instruction helpers by bringing them
in line with the Arm ARM definitions to make it easier to correlate
code with the document. No functional changes.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-17 14:56:01 +01:00
Will Deacon
b8925ee2e1 arm64: cpu: Move errata and feature enable callbacks closer to callers
The cpu errata and feature enable callbacks are only called via their
respective arm64_cpu_capabilities structure and therefore shouldn't
exist in the global namespace.

Move the PAN, RAS and cache maintenance emulation enable callbacks into
the same files as their corresponding arm64_cpu_capabilities structures,
making them static in the process.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:46:22 +01:00
Will Deacon
7c36447ae5 KVM: arm64: Set SCTLR_EL2.DSSBS if SSBD is forcefully disabled and !vhe
When running without VHE, it is necessary to set SCTLR_EL2.DSSBS if SSBD
has been forcefully disabled on the kernel command-line.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:46:20 +01:00
Will Deacon
8f04e8e6e2 arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3
On CPUs with support for PSTATE.SSBS, the kernel can toggle the SSBD
state without needing to call into firmware.

This patch hooks into the existing SSBD infrastructure so that SSBS is
used on CPUs that support it, but it's all made horribly complicated by
the very real possibility of big/little systems that don't uniformly
provide the new capability.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:46:19 +01:00
Will Deacon
d71be2b6c0 arm64: cpufeature: Detect SSBS and advertise to userspace
Armv8.5 introduces a new PSTATE bit known as Speculative Store Bypass
Safe (SSBS) which can be used as a mitigation against Spectre variant 4.

Additionally, a CPU may provide instructions to manipulate PSTATE.SSBS
directly, so that userspace can toggle the SSBS control without trapping
to the kernel.

This patch probes for the existence of SSBS and advertise the new instructions
to userspace if they exist.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:46:01 +01:00
Will Deacon
ca7f686ac9 arm64: Fix silly typo in comment
I was passing through and figuered I'd fix this up:

	featuer -> feature

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:42:04 +01:00
Will Deacon
7f08872774 arm64: tlb: Rewrite stale comment in asm/tlbflush.h
Peter Z asked me to justify the barrier usage in asm/tlbflush.h, but
actually that whole block comment needs to be rewritten.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:12 +01:00
Will Deacon
ace8cb7545 arm64: tlb: Avoid synchronous TLBIs when freeing page tables
By selecting HAVE_RCU_TABLE_INVALIDATE, we can rely on tlb_flush() being
called if we fail to batch table pages for freeing. This in turn allows
us to postpone walk-cache invalidation until tlb_finish_mmu(), which
avoids lots of unnecessary DSBs and means we can shoot down the ASID if
the range is large enough.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:12 +01:00
Will Deacon
f270ab88fd arm64: tlb: Adjust stride and type of TLBI according to mmu_gather
Now that the core mmu_gather code keeps track of both the levels of page
table cleared and also whether or not these entries correspond to
intermediate entries, we can use this in our tlb_flush() callback to
reduce the number of invalidations we issue as well as their scope.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:12 +01:00
Will Deacon
07212cd47e arm64: tlb: Remove redundant !CONFIG_HAVE_RCU_TABLE_FREE code
If there's one thing the RCU-based table freeing doesn't need, it's more
ifdeffery.

Remove the redundant !CONFIG_HAVE_RCU_TABLE_FREE code, since this option
is unconditionally selected in our Kconfig.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:12 +01:00
Will Deacon
67a902ac59 arm64: tlbflush: Allow stride to be specified for __flush_tlb_range()
When we are unmapping intermediate page-table entries or huge pages, we
don't need to issue a TLBI instruction for every PAGE_SIZE chunk in the
VA range being unmapped.

Allow the invalidation stride to be passed to __flush_tlb_range(), and
adjust our "just nuke the ASID" heuristic to take this into account.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:11 +01:00
Will Deacon
d8289d3a58 arm64: tlb: Justify non-leaf invalidation in flush_tlb_range()
Add a comment to explain why we can't get away with last-level
invalidation in flush_tlb_range()

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:11 +01:00
Will Deacon
0795edaf3f arm64: pgtable: Implement p[mu]d_valid() and check in set_p[mu]d()
Now that our walk-cache invalidation routines imply a DSB before the
invalidation, we no longer need one when we are clearing an entry during
unmap.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:11 +01:00
Will Deacon
45a284bc5e arm64: tlb: Add DSB ISHST prior to TLBI in __flush_tlb_[kernel_]pgtable()
__flush_tlb_[kernel_]pgtable() rely on set_pXd() having a DSB after
writing the new table entry and therefore avoid the barrier prior to the
TLBI instruction.

In preparation for delaying our walk-cache invalidation on the unmap()
path, move the DSB into the TLB invalidation routines.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:10 +01:00
Will Deacon
6899a4c82f arm64: tlb: Use last-level invalidation in flush_tlb_kernel_range()
flush_tlb_kernel_range() is only ever used to invalidate last-level
entries, so we can restrict the scope of the TLB invalidation
instruction.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-11 16:49:10 +01:00
Miguel Ojeda
13aceef06a arm64: jump_label.h: use asm_volatile_goto macro instead of "asm goto"
All other uses of "asm goto" go through asm_volatile_goto, which avoids
a miscompile when using GCC < 4.8.2. Replace our open-coded "asm goto"
statements with the asm_volatile_goto macro to avoid issues with older
toolchains.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-09-11 11:07:11 +01:00
Julien Thierry
a1f33941f7 arm64: uaccess: implement unsafe accessors
Current implementation of get/put_user_unsafe default to get/put_user
which toggle PAN before each access, despite having been told by the caller
that multiple accesses to user memory were about to happen.

Provide implementations for user_access_begin/end to turn PAN off/on and
implement unsafe accessors that assume PAN was already turned off.

Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-10 16:27:56 +01:00
Ard Biesheuvel
86d0dd34ea arm64: cpufeature: add feature for CRC32 instructions
Add a CRC32 feature bit and wire it up to the CPU id register so we
will be able to use alternatives patching for CRC32 operations.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-10 16:10:09 +01:00
Morten Rasmussen
3ba09df4b8 sched/topology, arch/arm64: Rebuild the sched_domain hierarchy when the CPU capacity changes
Asymmetric CPU capacity can not necessarily be determined accurately at
the time the initial sched_domain hierarchy is built during boot. It is
therefore necessary to be able to force a full rebuild of the hierarchy
later triggered by the arch_topology driver. A full rebuild requires the
arch-code to implement arch_update_cpu_topology() which isn't yet
implemented for arm64. This patch points the arm64 implementation to
arch_topology driver to ensure that full hierarchy rebuild happens when
needed.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: dietmar.eggemann@arm.com
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Link: http://lkml.kernel.org/r/1532093554-30504-4-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 11:05:47 +02:00
Christoph Hellwig
46053c7368 dma-mapping: clear dev->dma_ops in arch_teardown_dma_ops
There is no reason to leave the per-device dma_ops around when
deconfiguring a device, so move this code from arm64 into the
common code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-09-08 11:19:38 +02:00