Commit Graph

2069 Commits

Author SHA1 Message Date
Ard Biesheuvel
d26de6c9f4 arm64: drop unused kernel_neon_begin_partial() macro
When kernel mode NEON was first introduced to the arm64 kernel,
every call to kernel_neon_begin()/_end() stacked resp. unstacked
the entire NEON register file, making it worthwile to reduce the
number of used NEON registers to a bare minimum, and only stack
those. kernel_neon_begin_partial() was introduced for this purpose,
but after the refactoring for SVE and other changes, it no longer
exists and was simply #define'd to kernel_neon_begin() directly.

In the mean time, all users have been updated, so let's remove
the fallback macro.

Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-31 10:13:50 +01:00
Laura Abbott
0b3e336601 arm64: Add support for STACKLEAK gcc plugin
This adds support for the STACKLEAK gcc plugin to arm64 by implementing
stackleak_check_alloca(), based heavily on the x86 version, and adding the
two helpers used by the stackleak common code: current_top_of_stack() and
on_thread_stack(). The stack erasure calls are made at syscall returns.
Additionally, this disables the plugin in hypervisor and EFI stub code,
which are out of scope for the protection.

Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-26 11:36:34 +01:00
Laura Abbott
8a1ccfbc9e arm64: Add stack information to on_accessible_stack
In preparation for enabling the stackleak plugin on arm64,
we need a way to get the bounds of the current stack. Extend
on_accessible_stack to get this information.

Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
[will: folded in fix for allmodconfig build breakage w/ sdei]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-26 11:36:07 +01:00
AKASHI Takahiro
09ffcb0d71 arm64: acpi: fix alignment fault in accessing ACPI
This is a fix against the issue that crash dump kernel may hang up
during booting, which can happen on any ACPI-based system with "ACPI
Reclaim Memory."

(kernel messages after panic kicked off kdump)
	   (snip...)
	Bye!
	   (snip...)
	ACPI: Core revision 20170728
	pud=000000002e7d0003, *pmd=000000002e7c0003, *pte=00e8000039710707
	Internal error: Oops: 96000021 [#1] SMP
	Modules linked in:
	CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc6 #1
	task: ffff000008d05180 task.stack: ffff000008cc0000
	PC is at acpi_ns_lookup+0x25c/0x3c0
	LR is at acpi_ds_load1_begin_op+0xa4/0x294
	   (snip...)
	Process swapper/0 (pid: 0, stack limit = 0xffff000008cc0000)
	Call trace:
	   (snip...)
	[<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
	[<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
	[<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
	[<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
	[<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
	[<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
	[<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
	[<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
	[<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
	[<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
	[<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
	[<ffff000008badc20>] acpi_early_init+0x9c/0xd0
	[<ffff000008b70d50>] start_kernel+0x3b4/0x43c
	Code: b9008fb9 2a000318 36380054 32190318 (b94002c0)
	---[ end trace c46ed37f9651c58e ]---
	Kernel panic - not syncing: Fatal exception
	Rebooting in 10 seconds..

(diagnosis)
* This fault is a data abort, alignment fault (ESR=0x96000021)
  during reading out ACPI table.
* Initial ACPI tables are normally stored in system ram and marked as
  "ACPI Reclaim memory" by the firmware.
* After the commit f56ab9a5b7 ("efi/arm: Don't mark ACPI reclaim
  memory as MEMBLOCK_NOMAP"), those regions are differently handled
  as they are "memblock-reserved", without NOMAP bit.
* So they are now excluded from device tree's "usable-memory-range"
  which kexec-tools determines based on a current view of /proc/iomem.
* When crash dump kernel boots up, it tries to accesses ACPI tables by
  mapping them with ioremap(), not ioremap_cache(), in acpi_os_ioremap()
  since they are no longer part of mapped system ram.
* Given that ACPI accessor/helper functions are compiled in without
  unaligned access support (ACPI_MISALIGNMENT_NOT_SUPPORTED),
  any unaligned access to ACPI tables can cause a fatal panic.

With this patch, acpi_os_ioremap() always honors memory attribute
information provided by the firmware (EFI) and retaining cacheability
allows the kernel safe access to ACPI tables.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-23 15:34:12 +01:00
Mark Rutland
4378a7d4be arm64: implement syscall wrappers
To minimize the risk of userspace-controlled values being used under
speculation, this patch adds pt_regs based syscall wrappers for arm64,
which pass the minimum set of required userspace values to syscall
implementations. For each syscall, a wrapper which takes a pt_regs
argument is automatically generated, and this extracts the arguments
before calling the "real" syscall implementation.

Each syscall has three functions generated:

* __do_<compat_>sys_<name> is the "real" syscall implementation, with
  the expected prototype.

* __se_<compat_>sys_<name> is the sign-extension/narrowing wrapper,
  inherited from common code. This takes a series of long parameters,
  casting each to the requisite types required by the "real" syscall
  implementation in __do_<compat_>sys_<name>.

  This wrapper *may* not be necessary on arm64 given the AAPCS rules on
  unused register bits, but it seemed safer to keep the wrapper for now.

* __arm64_<compat_>_sys_<name> takes a struct pt_regs pointer, and
  extracts *only* the relevant register values, passing these on to the
  __se_<compat_>sys_<name> wrapper.

The syscall invocation code is updated to handle the calling convention
required by __arm64_<compat_>_sys_<name>, and passes a single struct
pt_regs pointer.

The compiler can fold the syscall implementation and its wrappers, such
that the overhead of this approach is minimized.

Note that we play games with sys_ni_syscall(). It can't be defined with
SYSCALL_DEFINE0() because we must avoid the possibility of error
injection. Additionally, there are a couple of locations where we need
to call it from C code, and we don't (currently) have a
ksys_ni_syscall().  While it has no wrapper, passing in a redundant
pt_regs pointer is benign per the AAPCS.

When ARCH_HAS_SYSCALL_WRAPPER is selected, no prototype is defines for
sys_ni_syscall(). Since we need to treat it differently for in-kernel
calls and the syscall tables, the prototype is defined as-required.

The wrappers are largely the same as their x86 counterparts, but
simplified as we don't have a variety of compat calling conventions that
require separate stubs. Unlike x86, we have some zero-argument compat
syscalls, and must define COMPAT_SYSCALL_DEFINE0() to ensure that these
are also given an __arm64_compat_sys_ prefix.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Catalin Marinas <catalin.marinas@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>
2018-07-12 14:49:48 +01:00
Mark Rutland
55f849265a arm64: convert compat wrappers to C
In preparation for converting to pt_regs syscall wrappers, convert our
existing compat wrappers to C. This will allow the pt_regs wrappers to
be automatically generated, and will allow for the compat register
manipulation to be folded in with the pt_regs accesses.

To avoid confusion with the upcoming pt_regs wrappers and existing
compat wrappers provided by core code, the C wrappers are renamed to
compat_sys_aarch32_<syscall>.

With the assembly wrappers gone, we can get rid of entry32.S and the
associated boilerplate.

Note that these must call the ksys_* syscall entry points, as the usual
sys_* entry points will be modified to take a single pt_regs pointer
argument.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-12 14:49:48 +01:00
Mark Rutland
3b7142752e arm64: convert native/compat syscall entry to C
Now that the syscall invocation logic is in C, we can migrate the rest
of the syscall entry logic over, so that the entry assembly needn't look
at the register values at all.

The SVE reset across syscall logic now unconditionally clears TIF_SVE,
but sve_user_disable() will only write back to CPACR_EL1 when SVE is
actually enabled.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-12 14:49:47 +01:00
Mark Rutland
27d83e68f3 arm64: introduce syscall_fn_t
In preparation for invoking arbitrary syscalls from C code, let's define
a type for an arbitrary syscall, matching the parameter passing rules of
the AAPCS.

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

Signed-off-by: Mark Rutland <mark.rutland@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>
2018-07-12 14:40:39 +01:00
Mark Rutland
3085e1645e arm64: remove sigreturn wrappers
The arm64 sigreturn* syscall handlers are non-standard. Rather than
taking a number of user parameters in registers as per the AAPCS,
they expect the pt_regs as their sole argument.

To make this work, we override the syscall definitions to invoke
wrappers written in assembly, which mov the SP into x0, and branch to
their respective C functions.

On other architectures (such as x86), the sigreturn* functions take no
argument and instead use current_pt_regs() to acquire the user
registers. This requires less boilerplate code, and allows for other
features such as interposing C code in this path.

This patch takes the same approach for arm64.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tentatively-reviewed-by: Dave Martin <dave.martin@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-12 14:40:39 +01:00
Mark Rutland
f9209e2629 arm64: move sve_user_{enable,disable} to <asm/fpsimd.h>
In subsequent patches, we'll want to make use of sve_user_enable() and
sve_user_disable() outside of kernel/fpsimd.c. Let's move these to
<asm/fpsimd.h> where we can make use of them.

To avoid ifdeffery in sequences like:

if (system_supports_sve() && some_condition)
	sve_user_disable();

... empty stubs are provided when support for SVE is not enabled. Note
that system_supports_sve() contains as IS_ENABLED(CONFIG_ARM64_SVE), so
the sve_user_disable() call should be optimized away entirely when
CONFIG_ARM64_SVE is not selected.

To ensure that this is the case, the stub definitions contain a
BUILD_BUG(), as we do for other stubs for which calls should always be
optimized away when the relevant config option is not selected.

At the same time, the include list of <asm/fpsimd.h> is sorted while
adding <asm/sysreg.h>.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-12 14:40:39 +01:00
Mark Rutland
25be597ada arm64: kill config_sctlr_el1()
Now that we have sysreg_clear_set(), we can consistently use this
instead of config_sctlr_el1().

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-12 14:40:38 +01:00
Mark Rutland
1c312e84c2 arm64: move SCTLR_EL{1,2} assertions to <asm/sysreg.h>
Currently we assert that the SCTLR_EL{1,2}_{SET,CLEAR} bits are
self-consistent with an assertion in config_sctlr_el1(). This is a bit
unusual, since config_sctlr_el1() doesn't make use of these definitions,
and is far away from the definitions themselves.

We can use the CPP #error directive to have equivalent assertions in
<asm/sysreg.h>, next to the definitions of the set/clear bits, which is
a bit clearer and simpler.

At the same time, lets fill in the upper 32 bits for both registers in
their respective RES0 definitions. This could be a little nicer with
GENMASK_ULL(63, 32), but this currently lives in <linux/bitops.h>, which
cannot safely be included from assembly, as <asm/sysreg.h> can.

Note the when the preprocessor evaluates an expression for an #if
directive, all signed or unsigned values are treated as intmax_t or
uintmax_t respectively. To avoid ambiguity, we define explicitly define
the mask of all 64 bits.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-12 14:40:38 +01:00
Will Deacon
409d5db498 arm64: rseq: Implement backend rseq calls and select HAVE_RSEQ
Implement calls to rseq_signal_deliver, rseq_handle_notify_resume
and rseq_syscall so that we can select HAVE_RSEQ on arm64.

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-11 13:29:34 +01:00
Lorenzo Pieralisi
e189624916 arm64: numa: rework ACPI NUMA initialization
Current ACPI ARM64 NUMA initialization code in

acpi_numa_gicc_affinity_init()

carries out NUMA nodes creation and cpu<->node mappings at the same time
in the arch backend so that a single SRAT walk is needed to parse both
pieces of information.  This implies that the cpu<->node mappings must
be stashed in an array (sized NR_CPUS) so that SMP code can later use
the stashed values to avoid another SRAT table walk to set-up the early
cpu<->node mappings.

If the kernel is configured with a NR_CPUS value less than the actual
processor entries in the SRAT (and MADT), the logic in
acpi_numa_gicc_affinity_init() is broken in that the cpu<->node mapping
is only carried out (and stashed for future use) only for a number of
SRAT entries up to NR_CPUS, which do not necessarily correspond to the
possible cpus detected at SMP initialization in
acpi_map_gic_cpu_interface() (ie MADT and SRAT processor entries order
is not enforced), which leaves the kernel with broken cpu<->node
mappings.

Furthermore, given the current ACPI NUMA code parsing logic in
acpi_numa_gicc_affinity_init(), PXM domains for CPUs that are not parsed
because they exceed NR_CPUS entries are not mapped to NUMA nodes (ie the
PXM corresponding node is not created in the kernel) leaving the system
with a broken NUMA topology.

Rework the ACPI ARM64 NUMA initialization process so that the NUMA
nodes creation and cpu<->node mappings are decoupled. cpu<->node
mappings are moved to SMP initialization code (where they are needed),
at the cost of an extra SRAT walk so that ACPI NUMA mappings can be
batched before being applied, fixing current parsing pitfalls.

Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: John Garry <john.garry@huawei.com>
Fixes: d8b47fca8c ("arm64, ACPI, NUMA: NUMA support based on SRAT and
SLIT")
Link: http://lkml.kernel.org/r/1527768879-88161-2-git-send-email-xiexiuqi@huawei.com
Reported-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com>
Cc: Jeremy Linton <jeremy.linton@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-09 18:21:40 +01:00
Sudeep Holla
f70ff12713 arm64: topology: rename llc_siblings to align with other struct members
Similar to core_sibling and thread_sibling, it's better to align and
rename llc_siblings to llc_sibling.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06 13:18:18 +01:00
Sudeep Holla
5bdd2b3f0f arm64: topology: add support to remove cpu topology sibling masks
This patch adds support to remove all the CPU topology information using
clear_cpu_topology and also resetting the sibling information on other
sibling CPUs. This will be used in cpu_disable so that all the topology
sibling information is removed on CPU hotplug out.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06 13:18:18 +01:00
Sudeep Holla
97fd6016a7 arm64: numa: separate out updates to percpu nodeid and NUMA node cpumap
Currently numa_clear_node removes both cpu information from the NUMA
node cpumap as well as the NUMA node id from the cpu. Similarly
numa_store_cpu_info updates both percpu nodeid and NUMA cpumap.

However we need to retain the numa node id for the cpu and only remove
the cpu information from the numa node cpumap during CPU hotplug out.
The same can be extended for hotplugging in the CPU.

This patch separates out numa_{add,remove}_cpu from numa_clear_node and
numa_store_cpu_info.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06 13:18:18 +01:00
Chintan Pandya
05f2d2f83b arm64: tlbflush: Introduce __flush_tlb_kernel_pgtable
Add an interface to invalidate intermediate page tables
from TLB for kernel.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06 13:17:14 +01:00
Will Deacon
693350a799 arm64: insn: Don't fallback on nosync path for general insn patching
Patching kernel instructions at runtime requires other CPUs to undergo
a context synchronisation event via an explicit ISB or an IPI in order
to ensure that the new instructions are visible. This is required even
for "hotpatch" instructions such as NOP and BL, so avoid optimising in
this case and always go via stop_machine() when performing general
patching.

ftrace isn't quite as strict, so it can continue to call the nosync
code directly.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 17:24:48 +01:00
Will Deacon
3b8c9f1cdf arm64: IPI each CPU after invalidating the I-cache for kernel mappings
When invalidating the instruction cache for a kernel mapping via
flush_icache_range(), it is also necessary to flush the pipeline for
other CPUs so that instructions fetched into the pipeline before the
I-cache invalidation are discarded. For example, if module 'foo' is
unloaded and then module 'bar' is loaded into the same area of memory,
a CPU could end up executing instructions from 'foo' when branching into
'bar' if these instructions were fetched into the pipeline before 'foo'
was unloaded.

Whilst this is highly unlikely to occur in practice, particularly as
any exception acts as a context-synchronizing operation, following the
letter of the architecture requires us to execute an ISB on each CPU
in order for the new instruction stream to be visible.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 17:24:36 +01:00
Mark Rutland
7373fed2f2 arm64: remove unused COMPAT_PSR definitions
Now that users have been migrated to PSR_AA32, kill the unused
COMPAT_PSR definitions.

The only difference we need a definition for is COMPAT_PSR_DIT_BIT,
which differs from PSR_AA32_DIT_BIT.

Signed-off-by: Mark Rutland <mark.rutland@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>
2018-07-05 17:24:15 +01:00
Mark Rutland
256c0960b7 kvm/arm: use PSR_AA32 definitions
Some code cares about the SPSR_ELx format for exceptions taken from
AArch32 to inspect or manipulate the SPSR_ELx value, which is already in
the SPSR_ELx format, and not in the AArch32 PSR format.

To separate these from cases where we care about the AArch32 PSR format,
migrate these cases to use the PSR_AA32_* definitions rather than
COMPAT_PSR_*.

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

Note that arm64 KVM does not support a compat KVM API, and always uses
the SPSR_ELx format, even for AArch32 guests.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 17:24:15 +01:00
Mark Rutland
d64567f678 arm64: use PSR_AA32 definitions
Some code cares about the SPSR_ELx format for exceptions taken from
AArch32 to inspect or manipulate the SPSR_ELx value, which is already in
the SPSR_ELx format, and not in the AArch32 PSR format.

To separate these from cases where we care about the AArch32 PSR format,
migrate these cases to use the PSR_AA32_* definitions rather than
COMPAT_PSR_*.

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

Signed-off-by: Mark Rutland <mark.rutland@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>
2018-07-05 17:24:14 +01:00
Mark Rutland
2508626342 arm64: add PSR_AA32_* definitions
The AArch32 CPSR/SPSR format is *almost* identical to the AArch64
SPSR_ELx format for exceptions taken from AArch32, but the two have
diverged with the addition of DIT, and we need to treat the two as
logically distinct.

This patch adds new definitions for the SPSR_ELx format for exceptions
taken from AArch32, with a consistent PSR_AA32_ prefix. The existing
COMPAT_PSR_ definitions will be used for the PSR format as seen from
AArch32.

Definitions of DIT are provided for both, and inline functions are
provided to map between the two formats. Note that for SPSR_ELx, the
(RES0) J bit has been re-allocated as the DIT bit.

Once users of the COMPAT_PSR definitions have been migrated over to the
PSR_AA32 definitions, the (majority of) the former will be removed, so
no efforts is made to avoid duplication until then.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 17:23:17 +01:00
Suzuki K Poulose
314d53d297 arm64: Handle mismatched cache type
Track mismatches in the cache type register (CTR_EL0), other
than the D/I min line sizes and trap user accesses if there are any.

Fixes: be68a8aaf9 ("arm64: cpufeature: Fix CTR_EL0 field definitions")
Cc: <stable@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 10:20:59 +01:00
Suzuki K Poulose
4c4a39dd5f arm64: Fix mismatched cache line size detection
If there is a mismatch in the I/D min line size, we must
always use the system wide safe value both in applications
and in the kernel, while performing cache operations. However,
we have been checking more bits than just the min line sizes,
which triggers false negatives. We may need to trap the user
accesses in such cases, but not necessarily patch the kernel.

This patch fixes the check to do the right thing as advertised.
A new capability will be added to check mismatches in other
fields and ensure we trap the CTR accesses.

Fixes: be68a8aaf9 ("arm64: cpufeature: Fix CTR_EL0 field definitions")
Cc: <stable@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 10:19:57 +01:00
Will Deacon
c11090474d arm64: locking: Replace ticket lock implementation with qspinlock
It's fair to say that our ticket lock has served us well over time, but
it's time to bite the bullet and start using the generic qspinlock code
so we can make use of explicit MCS queuing and potentially better PV
performance in future.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 10:05:06 +01:00
Will Deacon
598865c5f3 arm64: barrier: Implement smp_cond_load_relaxed
We can provide an implementation of smp_cond_load_relaxed using READ_ONCE
and __cmpwait_relaxed.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05 10:05:05 +01:00
Will Deacon
24fe1b0efa arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}
Commit 7f0b1bf045 ("arm64: Fix barriers used for page table modifications")
fixed a reported issue with fixmap page-table entries not being visible
to the walker due to a missing DSB instruction. At the same time, it added
ISB instructions to the arm64 set_{pte,pmd,pud} functions, which are not
required by the architecture and make little sense in isolation.

Remove the redundant ISBs.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-06-27 18:26:20 +01:00
Will Deacon
429388682d arm64: Avoid flush_icache_range() in alternatives patching code
The implementation of flush_icache_range() includes instruction sequences
which are themselves patched at runtime, so it is not safe to call from
the patching framework.

This patch reworks the alternatives cache-flushing code so that it rolls
its own internal D-cache maintenance using DC CIVAC before invalidating
the entire I-cache after all alternatives have been applied at boot.
Modules don't cause any issues, since flush_icache_range() is safe to
call by the time they are loaded.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Rohit Khanna <rokhanna@nvidia.com>
Cc: Alexander Van Brunt <avanbrunt@nvidia.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-06-27 18:21:53 +01:00
Dave Martin
b3eb56b629 KVM: arm64/sve: Fix SVE trap restoration for non-current tasks
Commit e6b673b ("KVM: arm64: Optimise FPSIMD handling to reduce
guest/host thrashing") attempts to restore the configuration of
userspace SVE trapping via a call to fpsimd_bind_task_to_cpu(), but
the logic for determining when to do this is not correct.

The patch makes the errnoenous assumption that the only task that
may try to enter userspace with the currently loaded FPSIMD/SVE
register content is current.  This may not be the case however:  if
some other user task T is scheduled on the CPU during the execution
of the KVM run loop, and the vcpu does not try to use the registers
in the meantime, then T's state may be left there intact.  If T
happens to be the next task to enter userspace on this CPU then the
hooks for reloading the register state and configuring traps will
be skipped.

(Also, current never has SVE state at this point anyway and should
always have the trap enabled, as a side-effect of the ioctl()
syscall needed to reach the KVM run loop in the first place.)

This patch instead restores the state of the EL0 trap from the
state observed at the most recent vcpu_load(), ensuring that the
trap is set correctly for the loaded context (if any).

Fixes: e6b673b741 ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing")
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-06-21 09:14:44 +01:00
Mark Rutland
6ebdf4db8f arm64: Introduce sysreg_clear_set()
Currently we have a couple of helpers to manipulate bits in particular
sysregs:

 * config_sctlr_el1(u32 clear, u32 set)

 * change_cpacr(u64 val, u64 mask)

The parameters of these differ in naming convention, order, and size,
which is unfortunate. They also differ slightly in behaviour, as
change_cpacr() skips the sysreg write if the bits are unchanged, which
is a useful optimization when sysreg writes are expensive.

Before we gain yet another sysreg manipulation function, let's
unify these with a common helper, providing a consistent order for
clear/set operands, and the write skipping behaviour from
change_cpacr(). Code will be migrated to the new helper in subsequent
patches.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-06-21 09:14:54 +01:00
Mauro Carvalho Chehab
5fb94e9ca3 docs: Fix some broken references
As we move stuff around, some doc references are broken. Fix some of
them via this script:
	./scripts/documentation-file-ref-check --fix

Manually checked if the produced result is valid, removing a few
false-positives.

Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15 18:10:01 -03:00
Linus Torvalds
b357bf6023 Small update for KVM.
* ARM: lazy context-switching of FPSIMD registers on arm64, "split"
 regions for vGIC redistributor
 
 * s390: cleanups for nested, clock handling, crypto, storage keys and
 control register bits
 
 * x86: many bugfixes, implement more Hyper-V super powers,
 implement lapic_timer_advance_ns even when the LAPIC timer
 is emulated using the processor's VMX preemption timer.  Two
 security-related bugfixes at the top of the branch.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small update for KVM:

  ARM:
   - lazy context-switching of FPSIMD registers on arm64
   - "split" regions for vGIC redistributor

  s390:
   - cleanups for nested
   - clock handling
   - crypto
   - storage keys
   - control register bits

  x86:
   - many bugfixes
   - implement more Hyper-V super powers
   - implement lapic_timer_advance_ns even when the LAPIC timer is
     emulated using the processor's VMX preemption timer.
   - two security-related bugfixes at the top of the branch"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (79 commits)
  kvm: fix typo in flag name
  kvm: x86: use correct privilege level for sgdt/sidt/fxsave/fxrstor access
  KVM: x86: pass kvm_vcpu to kvm_read_guest_virt and kvm_write_guest_virt_system
  KVM: x86: introduce linear_{read,write}_system
  kvm: nVMX: Enforce cpl=0 for VMX instructions
  kvm: nVMX: Add support for "VMWRITE to any supported field"
  kvm: nVMX: Restrict VMX capability MSR changes
  KVM: VMX: Optimize tscdeadline timer latency
  KVM: docs: nVMX: Remove known limitations as they do not exist now
  KVM: docs: mmu: KVM support exposing SLAT to guests
  kvm: no need to check return value of debugfs_create functions
  kvm: Make VM ioctl do valloc for some archs
  kvm: Change return type to vm_fault_t
  KVM: docs: mmu: Fix link to NPT presentation from KVM Forum 2008
  kvm: x86: Amend the KVM_GET_SUPPORTED_CPUID API documentation
  KVM: x86: hyperv: declare KVM_CAP_HYPERV_TLBFLUSH capability
  KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation
  KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE} implementation
  KVM: introduce kvm_make_vcpus_request_mask() API
  KVM: x86: hyperv: do rep check for each hypercall separately
  ...
2018-06-12 11:34:04 -07:00
Linus Torvalds
410feb75de arm64 updates for 4.18:
- Spectre v4 mitigation (Speculative Store Bypass Disable) support for
   arm64 using SMC firmware call to set a hardware chicken bit
 
 - ACPI PPTT (Processor Properties Topology Table) parsing support and
   enable the feature for arm64
 
 - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
   primary motivation is Scalable Vector Extensions which requires more
   space on the signal frame than the currently defined MINSIGSTKSZ
 
 - ARM perf patches: allow building arm-cci as module, demote dev_warn()
   to dev_dbg() in arm-ccn event_init(), miscellaneous cleanups
 
 - cmpwait() WFE optimisation to avoid some spurious wakeups
 
 - L1_CACHE_BYTES reverted back to 64 (for performance reasons that have
   to do with some network allocations) while keeping ARCH_DMA_MINALIGN
   to 128. cache_line_size() returns the actual hardware Cache Writeback
   Granule
 
 - Turn LSE atomics on by default in Kconfig
 
 - Kernel fault reporting tidying
 
 - Some #include and miscellaneous cleanups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "Apart from the core arm64 and perf changes, the Spectre v4 mitigation
  touches the arm KVM code and the ACPI PPTT support touches drivers/
  (acpi and cacheinfo). I should have the maintainers' acks in place.

  Summary:

   - Spectre v4 mitigation (Speculative Store Bypass Disable) support
     for arm64 using SMC firmware call to set a hardware chicken bit

   - ACPI PPTT (Processor Properties Topology Table) parsing support and
     enable the feature for arm64

   - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
     primary motivation is Scalable Vector Extensions which requires
     more space on the signal frame than the currently defined
     MINSIGSTKSZ

   - ARM perf patches: allow building arm-cci as module, demote
     dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous
     cleanups

   - cmpwait() WFE optimisation to avoid some spurious wakeups

   - L1_CACHE_BYTES reverted back to 64 (for performance reasons that
     have to do with some network allocations) while keeping
     ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual
     hardware Cache Writeback Granule

   - Turn LSE atomics on by default in Kconfig

   - Kernel fault reporting tidying

   - Some #include and miscellaneous cleanups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits)
  arm64: Fix syscall restarting around signal suppressed by tracer
  arm64: topology: Avoid checking numa mask for scheduler MC selection
  ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled
  arm64: cpu_errata: include required headers
  arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file
  arm64: signal: Report signal frame size to userspace via auxv
  arm64/sve: Thin out initialisation sanity-checks for sve_max_vl
  arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
  arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests
  arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
  arm64: KVM: Add HYP per-cpu accessors
  arm64: ssbd: Add prctl interface for per-thread mitigation
  arm64: ssbd: Introduce thread flag to control userspace mitigation
  arm64: ssbd: Restore mitigation status on CPU resume
  arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation
  arm64: ssbd: Add global mitigation state accessor
  arm64: Add 'ssbd' command-line option
  arm64: Add ARCH_WORKAROUND_2 probing
  arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2
  arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1
  ...
2018-06-08 11:10:58 -07:00
Laurent Dufour
3010a5ea66 mm: introduce ARCH_HAS_PTE_SPECIAL
Currently the PTE special supports is turned on in per architecture
header files.  Most of the time, it is defined in
arch/*/include/asm/pgtable.h depending or not on some other per
architecture static definition.

This patch introduce a new configuration variable to manage this
directly in the Kconfig files.  It would later replace
__HAVE_ARCH_PTE_SPECIAL.

Here notes for some architecture where the definition of
__HAVE_ARCH_PTE_SPECIAL is not obvious:

arm
 __HAVE_ARCH_PTE_SPECIAL which is currently defined in
arch/arm/include/asm/pgtable-3level.h which is included by
arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set.
So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE.

powerpc
__HAVE_ARCH_PTE_SPECIAL is defined in 2 files:
 - arch/powerpc/include/asm/book3s/64/pgtable.h
 - arch/powerpc/include/asm/pte-common.h
The first one is included if (PPC_BOOK3S & PPC64) while the second is
included in all the other cases.
So select ARCH_HAS_PTE_SPECIAL all the time.

sparc:
__HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) &&
defined(__arch64__) which are defined through the compiler in
sparc/Makefile if !SPARC32 which I assume to be if SPARC64.
So select ARCH_HAS_PTE_SPECIAL if SPARC64

There is no functional change introduced by this patch.

Link: http://lkml.kernel.org/r/1523433816-14460-2-git-send-email-ldufour@linux.vnet.ibm.com
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:35 -07:00
Linus Torvalds
ba252f16e4 Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull time/Y2038 updates from Thomas Gleixner:

 - Consolidate SySV IPC UAPI headers

 - Convert SySV IPC to the new COMPAT_32BIT_TIME mechanism

 - Cleanup the core interfaces and standardize on the ktime_get_* naming
   convention.

 - Convert the X86 platform ops to timespec64

 - Remove the ugly temporary timespec64 hack

* 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  x86: Convert x86_platform_ops to timespec64
  timekeeping: Add more coarse clocktai/boottime interfaces
  timekeeping: Add ktime_get_coarse_with_offset
  timekeeping: Standardize on ktime_get_*() naming
  timekeeping: Clean up ktime_get_real_ts64
  timekeeping: Remove timespec64 hack
  y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop
  y2038: ipc: Enable COMPAT_32BIT_TIME
  y2038: ipc: Use __kernel_timespec
  y2038: ipc: Report long times to user space
  y2038: ipc: Use ktime_get_real_seconds consistently
  y2038: xtensa: Extend sysvipc data structures
  y2038: powerpc: Extend sysvipc data structures
  y2038: sparc: Extend sysvipc data structures
  y2038: parisc: Extend sysvipc data structures
  y2038: mips: Extend sysvipc data structures
  y2038: arm64: Extend sysvipc compat data structures
  y2038: s390: Remove unneeded ipc uapi header files
  y2038: ia64: Remove unneeded ipc uapi header files
  y2038: alpha: Remove unneeded ipc uapi header files
  ...
2018-06-04 21:02:18 -07:00
Linus Torvalds
0bbcce5d1e Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers and timekeeping updates from Thomas Gleixner:

 - Core infrastucture work for Y2038 to address the COMPAT interfaces:

     + Add a new Y2038 safe __kernel_timespec and use it in the core
       code

     + Introduce config switches which allow to control the various
       compat mechanisms

     + Use the new config switch in the posix timer code to control the
       32bit compat syscall implementation.

 - Prevent bogus selection of CPU local clocksources which causes an
   endless reselection loop

 - Remove the extra kthread in the clocksource code which has no value
   and just adds another level of indirection

 - The usual bunch of trivial updates, cleanups and fixlets all over the
   place

 - More SPDX conversions

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  clocksource/drivers/mxs_timer: Switch to SPDX identifier
  clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier
  clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier
  clocksource/drivers/timer-imx-gpt: Remove outdated file path
  clocksource/drivers/arc_timer: Add comments about locking while read GFRC
  clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages
  clocksource/drivers/sprd: Fix Kconfig dependency
  clocksource: Move inline keyword to the beginning of function declarations
  timer_list: Remove unused function pointer typedef
  timers: Adjust a kernel-doc comment
  tick: Prefer a lower rating device only if it's CPU local device
  clocksource: Remove kthread
  time: Change nanosleep to safe __kernel_* types
  time: Change types to new y2038 safe __kernel_* types
  time: Fix get_timespec64() for y2038 safe compat interfaces
  time: Add new y2038 safe __kernel_timespec
  posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME
  time: Introduce CONFIG_COMPAT_32BIT_TIME
  time: Introduce CONFIG_64BIT_TIME in architectures
  compat: Enable compat_get/put_timespec64 always
  ...
2018-06-04 20:27:54 -07:00
Linus Torvalds
92400b8c8b Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:

 - Lots of tidying up changes all across the map for Linux's formal
   memory/locking-model tooling, by Alan Stern, Akira Yokosawa, Andrea
   Parri, Paul E. McKenney and SeongJae Park.

   Notable changes beyond an overall update in the tooling itself is the
   tidying up of spin_is_locked() semantics, which spills over into the
   kernel proper as well.

 - qspinlock improvements: the locking algorithm now guarantees forward
   progress whereas the previous implementation in mainline could starve
   threads indefinitely in cmpxchg() loops. Also other related cleanups
   to the qspinlock code (Will Deacon)

 - misc smaller improvements, cleanups and fixes all across the locking
   subsystem

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  locking/rwsem: Simplify the is-owner-spinnable checks
  tools/memory-model: Add reference for 'Simplifying ARM concurrency'
  tools/memory-model: Update ASPLOS information
  MAINTAINERS, tools/memory-model: Update e-mail address for Andrea Parri
  tools/memory-model: Fix coding style in 'lock.cat'
  tools/memory-model: Remove out-of-date comments and code from lock.cat
  tools/memory-model: Improve mixed-access checking in lock.cat
  tools/memory-model: Improve comments in lock.cat
  tools/memory-model: Remove duplicated code from lock.cat
  tools/memory-model: Flag "cumulativity" and "propagation" tests
  tools/memory-model: Add model support for spin_is_locked()
  tools/memory-model: Add scripts to test memory model
  tools/memory-model: Fix coding style in 'linux-kernel.def'
  tools/memory-model: Model 'smp_store_mb()'
  tools/memory-order: Update the cheat-sheet to show that smp_mb__after_atomic() orders later RMW operations
  tools/memory-order: Improve key for SELF and SV
  tools/memory-model: Fix cheat sheet typo
  tools/memory-model: Update required version of herdtools7
  tools/memory-model: Redefine rb in terms of rcu-fence
  tools/memory-model: Rename link and rcu-path to rcu-link and rb
  ...
2018-06-04 16:40:11 -07:00
Linus Torvalds
e5a594643a dma-mapping updates for 4.18:
- replaceme the force_dma flag with a dma_configure bus method.
    (Nipun Gupta, although one patch is іncorrectly attributed to me
     due to a git rebase bug)
  - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)
  - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
    right thing for bounce buffering.
  - move dma-debug initialization to common code, and apply a few cleanups
    to the dma-debug code.
  - cleanup the Kconfig mess around swiotlb selection
  - swiotlb comment fixup (Yisheng Xie)
  - a trivial swiotlb fix. (Dan Carpenter)
  - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)
  - add a new generic dma-noncoherent dma_map_ops implementation and use
    it for arc, c6x and nds32.
  - improve scatterlist validity checking in dma-debug. (Robin Murphy)
  - add a struct device quirk to limit the dma-mask to 32-bit due to
    bridge/system issues, and switch x86 to use it instead of a local
    hack for VIA bridges.
  - handle devices without a dma_mask more gracefully in the dma-direct
    code.
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Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - replace the force_dma flag with a dma_configure bus method. (Nipun
   Gupta, although one patch is іncorrectly attributed to me due to a
   git rebase bug)

 - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)

 - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
   right thing for bounce buffering.

 - move dma-debug initialization to common code, and apply a few
   cleanups to the dma-debug code.

 - cleanup the Kconfig mess around swiotlb selection

 - swiotlb comment fixup (Yisheng Xie)

 - a trivial swiotlb fix. (Dan Carpenter)

 - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)

 - add a new generic dma-noncoherent dma_map_ops implementation and use
   it for arc, c6x and nds32.

 - improve scatterlist validity checking in dma-debug. (Robin Murphy)

 - add a struct device quirk to limit the dma-mask to 32-bit due to
   bridge/system issues, and switch x86 to use it instead of a local
   hack for VIA bridges.

 - handle devices without a dma_mask more gracefully in the dma-direct
   code.

* tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits)
  dma-direct: don't crash on device without dma_mask
  nds32: use generic dma_noncoherent_ops
  nds32: implement the unmap_sg DMA operation
  nds32: consolidate DMA cache maintainance routines
  x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag
  x86/pci-dma: remove the explicit nodac and allowdac option
  x86/pci-dma: remove the experimental forcesac boot option
  Documentation/x86: remove a stray reference to pci-nommu.c
  core, dma-direct: add a flag 32-bit dma limits
  dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs
  dma-debug: check scatterlist segments
  c6x: use generic dma_noncoherent_ops
  arc: use generic dma_noncoherent_ops
  arc: fix arc_dma_{map,unmap}_page
  arc: fix arc_dma_sync_sg_for_{cpu,device}
  arc: simplify arc_dma_sync_single_for_{cpu,device}
  dma-mapping: provide a generic dma-noncoherent implementation
  dma-mapping: simplify Kconfig dependencies
  riscv: add swiotlb support
  riscv: only enable ZONE_DMA32 for 64-bit
  ...
2018-06-04 10:58:12 -07:00
Catalin Marinas
38500be10e arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file
This is to avoid potential merging conflicts between commit 55e3748e89
("arm64: KVM: Add ARCH_WORKAROUND_2 support for guests") and the KVM
tree.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-06-02 10:42:54 +01:00
Marc Orr
d1e5b0e98e kvm: Make VM ioctl do valloc for some archs
The kvm struct has been bloating. For example, it's tens of kilo-bytes
for x86, which turns out to be a large amount of memory to allocate
contiguously via kzalloc. Thus, this patch does the following:
1. Uses architecture-specific routines to allocate the kvm struct via
   vzalloc for x86.
2. Switches arm to __KVM_HAVE_ARCH_VM_ALLOC so that it can use vzalloc
   when has_vhe() is true.

Other architectures continue to default to kalloc, as they have a
dependency on kalloc or have a small-enough struct kvm.

Signed-off-by: Marc Orr <marcorr@google.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 19:18:26 +02:00
Paolo Bonzini
5eec43a1fa KVM/ARM updates for 4.18
- Lazy context-switching of FPSIMD registers on arm64
 - Allow virtual redistributors to be part of two or more MMIO ranges
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Merge tag 'kvmarm-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.18

- Lazy context-switching of FPSIMD registers on arm64
- Allow virtual redistributors to be part of two or more MMIO ranges
2018-06-01 19:17:22 +02:00
Dave Martin
94b07c1f8c arm64: signal: Report signal frame size to userspace via auxv
Stateful CPU architecture extensions may require the signal frame
to grow to a size that exceeds the arch's MINSIGSTKSZ #define.
However, changing this #define is an ABI break.

To allow userspace the option of determining the signal frame size
in a more forwards-compatible way, this patch adds a new auxv entry
tagged with AT_MINSIGSTKSZ, which provides the maximum signal frame
size that the process can observe during its lifetime.

If AT_MINSIGSTKSZ is absent from the aux vector, the caller can
assume that the MINSIGSTKSZ #define is sufficient.  This allows for
a consistent interface with older kernels that do not provide
AT_MINSIGSTKSZ.

The idea is that libc could expose this via sysconf() or some
similar mechanism.

There is deliberately no AT_SIGSTKSZ.  The kernel knows nothing
about userspace's own stack overheads and should not pretend to
know.

For arm64:

The primary motivation for this interface is the Scalable Vector
Extension, which can require at least 4KB or so of extra space
in the signal frame for the largest hardware implementations.

To determine the correct value, a "Christmas tree" mode (via the
add_all argument) is added to setup_sigframe_layout(), to simulate
addition of all possible records to the signal frame at maximum
possible size.

If this procedure goes wrong somehow, resulting in a stupidly large
frame layout and hence failure of sigframe_alloc() to allocate a
record to the frame, then this is indicative of a kernel bug.  In
this case, we WARN() and no attempt is made to populate
AT_MINSIGSTKSZ for userspace.

For arm64 SVE:

The SVE context block in the signal frame needs to be considered
too when computing the maximum possible signal frame size.

Because the size of this block depends on the vector length, this
patch computes the size based not on the thread's current vector
length but instead on the maximum possible vector length: this
determines the maximum size of SVE context block that can be
observed in any signal frame for the lifetime of the process.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-06-01 15:53:10 +01:00
Marc Zyngier
5d81f7dc9b arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
Now that all our infrastructure is in place, let's expose the
availability of ARCH_WORKAROUND_2 to guests. We take this opportunity
to tidy up a couple of SMCCC constants.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
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>
2018-05-31 18:00:59 +01:00
Marc Zyngier
55e3748e89 arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
In order to offer ARCH_WORKAROUND_2 support to guests, we need
a bit of infrastructure.

Let's add a flag indicating whether or not the guest uses
SSBD mitigation. Depending on the state of this flag, allow
KVM to disable ARCH_WORKAROUND_2 before entering the guest,
and enable it when exiting it.

Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
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>
2018-05-31 18:00:55 +01:00
Marc Zyngier
85478bab40 arm64: KVM: Add HYP per-cpu accessors
As we're going to require to access per-cpu variables at EL2,
let's craft the minimum set of accessors required to implement
reading a per-cpu variable, relying on tpidr_el2 to contain the
per-cpu offset.

Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
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>
2018-05-31 18:00:53 +01:00
Marc Zyngier
9dd9614f54 arm64: ssbd: Introduce thread flag to control userspace mitigation
In order to allow userspace to be mitigated on demand, let's
introduce a new thread flag that prevents the mitigation from
being turned off when exiting to userspace, and doesn't turn
it on on entry into the kernel (with the assumption that the
mitigation is always enabled in the kernel itself).

This will be used by a prctl interface introduced in a later
patch.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31 17:35:32 +01:00
Marc Zyngier
647d0519b5 arm64: ssbd: Restore mitigation status on CPU resume
On a system where firmware can dynamically change the state of the
mitigation, the CPU will always come up with the mitigation enabled,
including when coming back from suspend.

If the user has requested "no mitigation" via a command line option,
let's enforce it by calling into the firmware again to disable it.

Similarily, for a resume from hibernate, the mitigation could have
been disabled by the boot kernel. Let's ensure that it is set
back on in that case.

Acked-by: Will Deacon <will.deacon@arm.com>
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>
2018-05-31 17:35:19 +01:00
Marc Zyngier
c32e1736ca arm64: ssbd: Add global mitigation state accessor
We're about to need the mitigation state in various parts of the
kernel in order to do the right thing for userspace and guests.

Let's expose an accessor that will let other subsystems know
about the state.

Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31 17:34:57 +01:00