In order to support 52-bit kernel addresses detectable at boot time, one
needs to know the actual VA_BITS detected. A new variable vabits_actual
is introduced in this commit and employed for the KVM hypervisor layout,
KASAN, fault handling and phys-to/from-virt translation where there
would normally be compile time constants.
In order to maintain performance in phys_to_virt, another variable
physvirt_offset is introduced.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
In order to support 52-bit kernel addresses detectable at boot time, the
kernel needs to know the most conservative VA_BITS possible should it
need to fall back to this quantity due to lack of hardware support.
A new compile time constant VA_BITS_MIN is introduced in this patch and
it is employed in the KASAN end address, KASLR, and EFI stub.
For Arm, if 52-bit VA support is unavailable the fallback is to 48-bits.
In other words: VA_BITS_MIN = min (48, VA_BITS)
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 503 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__early_cpu_boot_status is of type long. Use quad
assembler directive to allocate proper size.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Arun KS <arunks@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Following assembly code is not trivial; make it slightly easier to read by
replacing some of the magic numbers with the defines which are already
present in sysreg.h.
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Updates to the GIC architecture allow ID_AA64PFR0_EL1.GIC to have
values other than 0 or 1. At the moment, Linux is quite strict in the
way it handles this field at early boot stage (cpufeature is fine) and
will refuse to use the system register CPU interface if it doesn't
find the value 1.
Fixes: 021f653791 ("irqchip: gic-v3: Initial support for GICv3")
Reported-by: Chase Conklin <Chase.Conklin@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
A side effect of commit c55191e96c ("arm64: mm: apply r/o permissions
of VM areas to its linear alias as well") is that the linear map is
created with page granularity, which means that transitioning the early
page table from global to non-global mappings when enabling kpti can
take a significant amount of time during boot.
Given that most CPU implementations do not require kpti, this mainly
impacts KASLR builds where kpti is forcefully enabled. However, in these
situations we know early on that non-global mappings are required and
can avoid the use of global mappings from the beginning. The only gotcha
is Cavium erratum #27456, which we must detect based on the MIDR value
of the boot CPU.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: John Garry <john.garry@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In KVM we define the configuration of HCR_EL2 for a VHE HOST in
HCR_HOST_VHE_FLAGS, but we don't have a similar definition for the
non-VHE host flags, and open-code HCR_RW. Further, in head.S we
open-code the flags for VHE and non-VHE configurations.
In future, we're going to want to configure more flags for the host, so
lets add a HCR_HOST_NVHE_FLAGS defintion, and consistently use both
HCR_HOST_VHE_FLAGS and HCR_HOST_NVHE_FLAGS in the kvm code and head.S.
We now use mov_q to generate the HCR_EL2 value, as we use when
configuring other registers in head.S.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Will Deacon <will.deacon@arm.com>
Rather than add additional variables to detect specific early feature
mismatches with secondary CPUs, we can instead dedicate the upper bits
of the CPU boot status word to flag specific mismatches.
This allows us to communicate both granule and VA-size mismatches back
to the primary CPU without the need for additional book-keeping.
Tested-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Enabling 52-bit VAs for userspace is pretty confusing, since it requires
you to select "48-bit" virtual addressing in the Kconfig.
Rework the logic so that 52-bit user virtual addressing is advertised in
the "Virtual address space size" choice, along with some help text to
describe its interaction with Pointer Authentication. The EXPERT-only
option to force all user mappings to the 52-bit range is then made
available immediately below the VA size selection.
Signed-off-by: Will Deacon <will.deacon@arm.com>
On arm64 there is optional support for a 52-bit virtual address space.
To exploit this one has to be running with a 64KB page size and be
running on hardware that supports this.
For an arm64 kernel supporting a 48 bit VA with a 64KB page size,
some changes are needed to support a 52-bit userspace:
* TCR_EL1.T0SZ needs to be 12 instead of 16,
* TASK_SIZE needs to reflect the new size.
This patch implements the above when the support for 52-bit VAs is
detected at early boot time.
On arm64 userspace addresses translation is controlled by TTBR0_EL1. As
well as userspace, TTBR0_EL1 controls:
* The identity mapping,
* EFI runtime code.
It is possible to run a kernel with an identity mapping that has a
larger VA size than userspace (and for this case __cpu_set_tcr_t0sz()
would set TCR_EL1.T0SZ as appropriate). However, when the conditions for
52-bit userspace are met; it is possible to keep TCR_EL1.T0SZ fixed at
12. Thus in this patch, the TCR_EL1.T0SZ size changing logic is
disabled.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
For cases where there is a mismatch in ARMv8.2-LVA support between CPUs
we have to be careful in allowing secondary CPUs to boot if 52-bit
virtual addresses have already been enabled on the boot CPU.
This patch adds code to the secondary startup path. If the boot CPU has
enabled 52-bit VAs then ID_AA64MMFR2_EL1 is checked to see if the
secondary can also enable 52-bit support. If not, the secondary is
prevented from booting and an error message is displayed indicating why.
Technically this patch could be implemented using the cpufeature code
when considering 52-bit userspace support. However, we employ low level
checks here as the cpufeature code won't be able to run if we have
mismatched 52-bit kernel va support.
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Enabling 52-bit VAs on arm64 requires that the PGD table expands from 64
entries (for the 48-bit case) to 1024 entries. This quantity,
PTRS_PER_PGD is used as follows to compute which PGD entry corresponds
to a given virtual address, addr:
pgd_index(addr) -> (addr >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)
Userspace addresses are prefixed by 0's, so for a 48-bit userspace
address, uva, the following is true:
(uva >> PGDIR_SHIFT) & (1024 - 1) == (uva >> PGDIR_SHIFT) & (64 - 1)
In other words, a 48-bit userspace address will have the same pgd_index
when using PTRS_PER_PGD = 64 and 1024.
Kernel addresses are prefixed by 1's so, given a 48-bit kernel address,
kva, we have the following inequality:
(kva >> PGDIR_SHIFT) & (1024 - 1) != (kva >> PGDIR_SHIFT) & (64 - 1)
In other words a 48-bit kernel virtual address will have a different
pgd_index when using PTRS_PER_PGD = 64 and 1024.
If, however, we note that:
kva = 0xFFFF << 48 + lower (where lower[63:48] == 0b)
and, PGDIR_SHIFT = 42 (as we are dealing with 64KB PAGE_SIZE)
We can consider:
(kva >> PGDIR_SHIFT) & (1024 - 1) - (kva >> PGDIR_SHIFT) & (64 - 1)
= (0xFFFF << 6) & 0x3FF - (0xFFFF << 6) & 0x3F // "lower" cancels out
= 0x3C0
In other words, one can switch PTRS_PER_PGD to the 52-bit value globally
provided that they increment ttbr1_el1 by 0x3C0 * 8 = 0x1E00 bytes when
running with 48-bit kernel VAs (TCR_EL1.T1SZ = 16).
For kernel configuration where 52-bit userspace VAs are possible, this
patch offsets ttbr1_el1 and sets PTRS_PER_PGD corresponding to the
52-bit value.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
[will: added comment to TTBR1_BADDR_4852_OFFSET calculation]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Those image head's flags will be used later by kexec_file loader.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that deliberate writes to swapper_pg_dir are made via the fixmap, we
can defend against errant writes by moving it into the rodata section.
Since tramp_pg_dir and reserved_ttbr0 must be at a fixed offset from
swapper_pg_dir, and are not modified at runtime, these are also moved
into the rodata section. Likewise, idmap_pg_dir is not modified at
runtime, and is moved into rodata.
Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: simplify linker script, commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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>
In subsequent patches we'll use a transient pgd during the primary cpu's
boot process. To make this work while allowing secondary cpus to use the
swapper_pg_dir, we need to pass the relevant TTBR1 pgd as a parameter
to __enable_mmu().
This patch updates __enable__mmu() to take this as a parameter, updating
callsites to pass swapper_pg_dir for now.
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: simplify assembly, clarify commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We don't currently limit guest accesses to the LOR registers, which we
neither virtualize nor context-switch. As such, guests are provided with
unusable information/controls, and are not isolated from each other (or
the host).
To prevent these issues, we can trap register accesses and present the
illusion LORegions are unssupported by the CPU. To do this, we mask
ID_AA64MMFR1.LO, and set HCR_EL2.TLOR to trap accesses to the following
registers:
* LORC_EL1
* LOREA_EL1
* LORID_EL1
* LORN_EL1
* LORSA_EL1
... when trapped, we inject an UNDEFINED exception to EL1, simulating
their non-existence.
As noted in D7.2.67, when no LORegions are implemented, LoadLOAcquire
and StoreLORelease must behave as LoadAcquire and StoreRelease
respectively. We can ensure this by clearing LORC_EL1.EN when a CPU's
EL2 is first initialized, as the host kernel will not modify this.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The identity map is mapped as both writeable and executable by the
SWAPPER_MM_MMUFLAGS and this is relied upon by the kpti code to manage
a synchronisation flag. Update the .pushsection flags to reflect the
actual mapping attributes.
Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
pte_to_phys lives in assembler.h and takes its destination register as
the first argument. Move phys_to_pte out of head.S to sit with its
counterpart and rejig it to follow the same calling convention.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Since AArch64 assembly instructions take the destination register as
their first operand, do the same thing for the phys_to_ttbr macro.
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The ARM architecture defines the memory locations that are permitted
to be accessed as the result of a speculative instruction fetch from
an exception level for which all stages of translation are disabled.
Specifically, the core is permitted to speculatively fetch from the
4KB region containing the current program counter 4K and next 4K.
When translation is changed from enabled to disabled for the running
exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the
Falkor core may errantly speculatively access memory locations outside
of the 4KB region permitted by the architecture. The errant memory
access may lead to one of the following unexpected behaviors.
1) A System Error Interrupt (SEI) being raised by the Falkor core due
to the errant memory access attempting to access a region of memory
that is protected by a slave-side memory protection unit.
2) Unpredictable device behavior due to a speculative read from device
memory. This behavior may only occur if the instruction cache is
disabled prior to or coincident with translation being changed from
enabled to disabled.
The conditions leading to this erratum will not occur when either of the
following occur:
1) A higher exception level disables translation of a lower exception level
(e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0).
2) An exception level disabling its stage-1 translation if its stage-2
translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1
to 0 when HCR_EL2[VM] has a value of 1).
To avoid the errant behavior, software must execute an ISB immediately
prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0.
Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
__cpu_setup() configures SCTLR_EL1 using some hard coded hex masks,
and el2_setup() duplicates some this when setting RES1 bits.
Lets make this the same as KVM's hyp_init, which uses named bits.
First, we add definitions for all the SCTLR_EL{1,2} bits, the RES{1,0}
bits, and those we want to set or clear.
Add a build_bug checks to ensures all bits are either set or clear.
This means we don't need to preserve endian-ness configuration
generated elsewhere.
Finally, move the head.S and proc.S users of these hard-coded masks
over to the macro versions.
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Currently the early assembler page table code assumes that precisely
1xpgd, 1xpud, 1xpmd are sufficient to represent the early kernel text
mappings.
Unfortunately this is rarely the case when running with a 16KB granule,
and we also run into limits with 4KB granule when building much larger
kernels.
This patch re-writes the early page table logic to compute indices of
mappings for each level of page table, and if multiple indices are
required, the next-level page table is scaled up accordingly.
Also the required size of the swapper_pg_dir is computed at link time
to cover the mapping [KIMAGE_ADDR + VOFFSET, _end]. When KASLR is
enabled, an extra page is set aside for each level that may require extra
entries at runtime.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Currently, when using VA_BITS < 48, if the ID map text happens to be
placed in physical memory above VA_BITS, we increase the VA size (up to
48) and create a new table level, in order to map in the ID map text.
This is okay because the system always supports 48 bits of VA.
This patch extends the code such that if the system supports 52 bits of
VA, and the ID map text is placed that high up, then we increase the VA
size accordingly, up to 52.
One difference from the current implementation is that so far the
condition of VA_BITS < 48 has meant that the top level table is always
"full", with the maximum number of entries, and an extra table level is
always needed. Now, when VA_BITS = 48 (and using 64k pages), the top
level table is not full, and we simply need to increase the number of
entries in it, instead of creating a new table level.
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()]
[catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The top 4 bits of a 52-bit physical address are positioned at bits
12..15 of a page table entry. Introduce macros to convert between a
physical address and its placement in a table entry, and change all
macros/functions that access PTEs to use them.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: some long lines wrapped]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The top 4 bits of a 52-bit physical address are positioned at bits
12..15 in page table entries. Introduce a macro to move the bits there,
and change the early ID map and swapper table setup code to use it.
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: additional comments for clarification]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The top 4 bits of a 52-bit physical address are positioned at bits 2..5
in the TTBR registers. Introduce a couple of macros to move the bits
there, and change all TTBR writers to use them.
Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with
52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a
system without 52-bit PA can only use up to 48-bit PAs. A later patch in
this series will add a kconfig dependency to ensure PAN is configured.
In addition, when using 52-bit PA there is a special alignment
requirement on the top-level table. We don't currently have any VA_BITS
configuration that would violate the requirement, but one could be added
in the future, so add a compile-time BUG_ON to check for it.
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
When booting at EL2, ensure that we permit the EL1 host to sample
physical addresses and physical counter values using SPE.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
When the kernel is entered at EL2 on an ARMv8.0 system, we construct
the EL1 pstate and make sure this uses the the EL1 stack pointer
(we perform an exception return to EL1h).
But if the kernel is either entered at EL1 or stays at EL2 (because
we're on a VHE-capable system), we fail to set SPsel, and use whatever
stack selection the higher exception level has choosen for us.
Let's not take any chance, and make sure that SPsel is set to one
before we decide the mode we're going to run in.
Cc: <stable@vger.kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
- VMAP_STACK support, allowing the kernel stacks to be allocated in
the vmalloc space with a guard page for trapping stack overflows. One
of the patches introduces THREAD_ALIGN and changes the generic
alloc_thread_stack_node() to use this instead of THREAD_SIZE (no
functional change for other architectures)
- Contiguous PTE hugetlb support re-enabled (after being reverted a
couple of times). We now have the semantics agreed in the generic mm
layer together with API improvements so that the architecture code can
detect between contiguous and non-contiguous huge PTEs
- Initial support for persistent memory on ARM: DC CVAP instruction
exposed to user space (HWCAP) and the in-kernel pmem API implemented
- raid6 improvements for arm64: faster algorithm for the delta syndrome
and implementation of the recovery routines using Neon
- FP/SIMD refactoring and removal of support for Neon in interrupt
context. This is in preparation for full SVE support
- PTE accessors converted from inline asm to cmpxchg so that we can
use LSE atomics if available (ARMv8.1)
- Perf support for Cortex-A35 and A73
- Non-urgent fixes and 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:
- VMAP_STACK support, allowing the kernel stacks to be allocated in the
vmalloc space with a guard page for trapping stack overflows. One of
the patches introduces THREAD_ALIGN and changes the generic
alloc_thread_stack_node() to use this instead of THREAD_SIZE (no
functional change for other architectures)
- Contiguous PTE hugetlb support re-enabled (after being reverted a
couple of times). We now have the semantics agreed in the generic mm
layer together with API improvements so that the architecture code
can detect between contiguous and non-contiguous huge PTEs
- Initial support for persistent memory on ARM: DC CVAP instruction
exposed to user space (HWCAP) and the in-kernel pmem API implemented
- raid6 improvements for arm64: faster algorithm for the delta syndrome
and implementation of the recovery routines using Neon
- FP/SIMD refactoring and removal of support for Neon in interrupt
context. This is in preparation for full SVE support
- PTE accessors converted from inline asm to cmpxchg so that we can use
LSE atomics if available (ARMv8.1)
- Perf support for Cortex-A35 and A73
- Non-urgent fixes and cleanups
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (75 commits)
arm64: cleanup {COMPAT_,}SET_PERSONALITY() macro
arm64: introduce separated bits for mm_context_t flags
arm64: hugetlb: Cleanup setup_hugepagesz
arm64: Re-enable support for contiguous hugepages
arm64: hugetlb: Override set_huge_swap_pte_at() to support contiguous hugepages
arm64: hugetlb: Override huge_pte_clear() to support contiguous hugepages
arm64: hugetlb: Handle swap entries in huge_pte_offset() for contiguous hugepages
arm64: hugetlb: Add break-before-make logic for contiguous entries
arm64: hugetlb: Spring clean huge pte accessors
arm64: hugetlb: Introduce pte_pgprot helper
arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present
arm64: kexec: have own crash_smp_send_stop() for crash dump for nonpanic cores
arm64: dma-mapping: Mark atomic_pool as __ro_after_init
arm64: dma-mapping: Do not pass data to gen_pool_set_algo()
arm64: Remove the !CONFIG_ARM64_HW_AFDBM alternative code paths
arm64: Ignore hardware dirty bit updates in ptep_set_wrprotect()
arm64: Move PTE_RDONLY bit handling out of set_pte_at()
kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg()
arm64: Convert pte handling from inline asm to using (cmp)xchg
arm64: neon/efi: Make EFI fpsimd save/restore variables static
...
In the KASLR setup routine, we ensure that the early virtual mapping
of the kernel image does not cover more than a single table entry at
the level above the swapper block level, so that the assembler routines
involved in setting up this mapping can remain simple.
In this calculation we add the proposed KASLR offset to the values of
the _text and _end markers, and reject it if they would end up falling
in different swapper table sized windows.
However, when taking the addresses of _text and _end, the modulo offset
(the physical displacement modulo 2 MB) is already accounted for, and
so adding it again results in incorrect results. So disregard the modulo
offset from the calculation.
Fixes: 08cdac619c ("arm64: relocatable: deal with physically misaligned ...")
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
As it turns out, the unwind code is slightly broken, and probably has
been for a while. The problem is in the dumping of the exception stack,
which is intended to dump the contents of the pt_regs struct at each
level in the call stack where an exception was taken and routed to a
routine marked as __exception (which means its stack frame is right
below the pt_regs struct on the stack).
'Right below the pt_regs struct' is ill defined, though: the unwind
code assigns 'frame pointer + 0x10' to the .sp member of the stackframe
struct at each level, and dump_backtrace() happily dereferences that as
the pt_regs pointer when encountering an __exception routine. However,
the actual size of the stack frame created by this routine (which could
be one of many __exception routines we have in the kernel) is not known,
and so frame.sp is pretty useless to figure out where struct pt_regs
really is.
So it seems the only way to ensure that we can find our struct pt_regs
when walking the stack frames is to put it at a known fixed offset of
the stack frame pointer that is passed to such __exception routines.
The simplest way to do that is to put it inside pt_regs itself, which is
the main change implemented by this patch. As a bonus, doing this allows
us to get rid of a fair amount of cruft related to walking from one stack
to the other, which is especially nice since we intend to introduce yet
another stack for overflow handling once we add support for vmapped
stacks. It also fixes an inconsistency where we only add a stack frame
pointing to ELR_EL1 if we are executing from the IRQ stack but not when
we are executing from the task stack.
To consistly identify exceptions regs even in the presence of exceptions
taken from entry code, we must check whether the next frame was created
by entry text, rather than whether the current frame was crated by
exception text.
To avoid backtracing using PCs that fall in the idmap, or are controlled
by userspace, we must explcitly zero the FP and LR in startup paths, and
must ensure that the frame embedded in pt_regs is zeroed upon entry from
EL0. To avoid these NULL entries showin in the backtrace, unwind_frame()
is updated to avoid them.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[Mark: compare current frame against .entry.text, avoid bogus PCs]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
__inval_cache_range() is already the odd one out among our data cache
maintenance routines as the only remaining range-based one; as we're
going to want an invalidation routine to call from C code for the pmem
API, let's tweak the prototype and name to bring it in line with the
clean operations, and to make its relationship with __dma_inv_area()
neatly mirror that of __clean_dcache_area_poc() and __dma_clean_area().
The loop clearing the early page tables gets mildly massaged in the
process for the sake of consistency.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
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>
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>
Unlike most sysreg defintiions, the GICv3 definitions don't have a SYS_
prefix, and they don't live in <asm/sysreg.h>. Additionally, some
definitions are duplicated elsewhere (e.g. in the KVM save/restore
code).
For consistency, and to make it possible to share a common definition
for these sysregs, this patch moves the definitions to <asm/sysreg.h>,
adding a SYS_ prefix, and sorting the registers per their encoding.
Existing users of the definitions are fixed up so that this change is
not problematic.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
The SPE architecture requires each exception level to enable access
to the SPE controls for the exception level below it, since additional
context-switch logic may be required to handle the buffer safely.
This patch allows EL1 (host) access to the SPE controls when entered at
EL2.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
When building with debugging symbols, take the absolute path to the
vmlinux binary and add it to the special PE/COFF debug table entry.
This allows a debug EFI build to find the vmlinux binary, which is
very helpful in debugging, given that the offset where the Image is
first loaded by EFI is highly unpredictable.
On implementations of UEFI that choose to implement it, this
information is exposed via the EFI debug support table, which is a UEFI
configuration table that is accessible both by the firmware at boot time
and by the OS at runtime, and lists all PE/COFF images loaded by the
system.
The format of the NB10 Codeview entry is based on the definition used
by EDK2, which is our primary reference when it comes to the use of
PE/COFF in the context of UEFI firmware.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: use realpath instead of shell invocation, as discussed on list]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Some places in the kernel open-code sequences using ADRP for a symbol
another instruction using a :lo12: relocation for that same symbol.
These sequences are easy to get wrong, and more painful to read than is
necessary. For these reasons, it is preferable to use the
{adr,ldr,str}_l macros for these cases.
This patch makes use of adr_l these in head.S, removing an open-coded
sequence using adrp.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In commit 23c8a500c2 ("arm64: kernel: use ordinary return/argument
register for el2_setup()"), we stopped using w20 as a global stash of
the boot mode flag, and instead pass this around in w0 as a function
parameter.
Unfortunately, we missed a couple of comments, which still refer to the
old convention of using w20/x20.
This patch fixes up the comments to describe the code as it currently
works.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Bit positions of CNTHCTL_EL2 are changing depending on HCR_EL2.E2H bit.
EL1PCEN and EL1PCTEN are 1st and 0th bits when E2H is not set, but they
are 11th and 10th bits respectively when E2H is set. Current code is
unintentionally setting wrong bits to CNTHCTL_EL2 with E2H set.
In fact, we don't need to set those two bits, which allow EL1 and EL0 to
access physical timer and counter respectively, if E2H and TGE are set
for the host kernel. They will be configured later as necessary. First,
we don't need to configure those bits for EL1, since the host kernel
runs in EL2. It is a hypervisor's responsibility to configure them
before entering a VM, which runs in EL0 and EL1. Second, EL0 accesses
are configured in the later stage of boot process.
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch adds the uaccess macros/functions to disable access to user
space by setting TTBR0_EL1 to a reserved zeroed page. Since the value
written to TTBR0_EL1 must be a physical address, for simplicity this
patch introduces a reserved_ttbr0 page at a constant offset from
swapper_pg_dir. The uaccess_disable code uses the ttbr1_el1 value
adjusted by the reserved_ttbr0 offset.
Enabling access to user is done by restoring TTBR0_EL1 with the value
from the struct thread_info ttbr0 variable. Interrupts must be disabled
during the uaccess_ttbr0_enable code to ensure the atomicity of the
thread_info.ttbr0 read and TTBR0_EL1 write. This patch also moves the
get_thread_info asm macro from entry.S to assembler.h for reuse in the
uaccess_ttbr0_* macros.
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch moves arm64's struct thread_info from the task stack into
task_struct. This protects thread_info from corruption in the case of
stack overflows, and makes its address harder to determine if stack
addresses are leaked, making a number of attacks more difficult. Precise
detection and handling of overflow is left for subsequent patches.
Largely, this involves changing code to store the task_struct in sp_el0,
and acquire the thread_info from the task struct. Core code now
implements current_thread_info(), and as noted in <linux/sched.h> this
relies on offsetof(task_struct, thread_info) == 0, enforced by core
code.
This change means that the 'tsk' register used in entry.S now points to
a task_struct, rather than a thread_info as it used to. To make this
clear, the TI_* field offsets are renamed to TSK_TI_*, with asm-offsets
appropriately updated to account for the structural change.
Userspace clobbers sp_el0, and we can no longer restore this from the
stack. Instead, the current task is cached in a per-cpu variable that we
can safely access from early assembly as interrupts are disabled (and we
are thus not preemptible).
Both secondary entry and idle are updated to stash the sp and task
pointer separately.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Steve Capper