This code is non-obvious when reading for the first time. To help with
understanding of it add comments explaining what it's doing.
While here use macros from armreg.h rather than magic numbers.
Sponsored by: DARPA, AFRL
This is a 32-bit structure embedded in each vm_page, consisting mostly
of page queue state. The use of a structure makes it easy to store a
snapshot of a page's queue state in a stack variable and use cmpset
loops to update that state without requiring the page lock.
This change merely adds the structure and updates references to atomic
state fields. No functional change intended.
Reviewed by: alc, jeff, kib
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D22650
In some cases, like is locked bootstrap or device's inability to boot from
removable media, we cannot use standard boot sequence and is necessary to
boot kernel directly from U-Boot.
Discussed with: jhibbits
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D13861
o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
All Rights Reserved on same line as other copyright holders (but not
me). Other such holders are also listed last where it's clear.
After discussing with mmel@, it was clear this is insufficient to address
all the needs. mmel@ will commit his original patch, from
https://reviews.freebsd.org/D13861, and the additions needed from r354714
will be made afterward.
Requested by: mmel
Sponsored by: Juniper Networks, Inc.
Update the NetBSD Kernel Concurrency Sanitizer (KCSAN) runtime to work in
the FreeBSD kernel. It is a useful tool for finding data races between
threads executing on different CPUs.
This can be enabled by enabling KCSAN in the kernel config, or by using the
GENERIC-KCSAN amd64 kernel. It works on amd64 and arm64, however the later
needs a compiler change to allow -fsanitize=thread that KCSAN uses.
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22315
Summary:
Boot arm64 kernel using booti command from U-boot. booti can relocate initrd
image into higher ram addresses, therefore align the initrd load address to 1GiB
and create VA = PA map for it. Create L2 pagetable entries to copy the initrd
image into KVA.
(parts of the code in https://reviews.freebsd.org/D13861 was referred and used
as appropriate)
Submitted by: Siddharth Tuli <siddharthtuli_gmail.com>
Reviewed by: manu
Sponsored by: Juniper Networks, Inc
Differential Revision: https://reviews.freebsd.org/D22255
These are direct copies of the 32 bit functions, adjusted ad needed.
While here fix atomic_fcmpset_16 to use the valid load and store exclusive
instructions.
Sponsored by: DARPA, AFRL
Some userland libraries incude machine/pcb.h and this needs the full
definition of struct debug_monitor_state. To allow this to work move
stuct debug_monitor_state out of the _KERNEL guard.
Sponsored by: DARPA, AFRL
switching. The indirect costs being unnecessary TLB misses that are
incurred when ASIDs are not used. In fact, currently, when we perform a
context switch on one processor, we issue a broadcast TLB invalidation that
flushes the TLB contents on every processor.
Mark all user-space ("ttbr0") page table entries with the non-global flag so
that they are cached in the TLB under their ASID.
Correct an error in pmap_pinit0(). The pointer to the root of the page
table was being initialized to the root of the kernel-space page table
rather than a user-space page table. However, the root of the page table
that was being cached in process 0's md_l0addr field correctly pointed to a
user-space page table. As long as ASIDs weren't being used, this was
harmless, except that it led to some unnecessary page table switches in
pmap_switch(). Specifically, other kernel processes besides process 0 would
have their md_l0addr field set to the root of the kernel-space page table,
and so pmap_switch() would actually change page tables when switching
between process 0 and other kernel processes.
Implement a workaround for Cavium erratum 27456 affecting ThunderX machines.
(I would like to thank andrew@ for providing the code to detect the affected
machines.)
Address integer overflow in the definition of TCR_ASID_16.
Setup TCR according to the PARange and ASIDBits fields from
ID_AA64MMFR0_EL1. Previously, TCR_ASID_16 was unconditionally set.
Modify build_l1_block_pagetable so that lower attributes, such as ATTR_nG,
can be specified as a parameter.
Eliminate some unused code.
Earlier versions were tested to varying degrees by: andrew, emaste, markj
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D21922
Implement get/fill_dbregs on arm64. This is used by ptrace with the
PT_GETDBREGS and PT_SETDBREGS requests. It allows userspace to set hardware
breakpoints.
The struct dbreg is based on Linux to ease adding hardware breakpoint
support to debuggers.
Reviewed by: jhb
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22195
We may want to mask exceptions when in userspace. This was previously
impossible as threads are created with all exceptions unmasked and
signals expected userspace to mask any. Fix these by copying the
mask state on thread creation and allow exceptions to be masked on
signal return, as long as they don't change.
Sponsored by: DARPA, AFRL
To allow consistent values to be used in both the kernel and userspace
create a function for these to be read from the kernel. They use a newly
created macro with the name of the ID register to read. For now there is
redundant information in the user_regs array as it still holds the CRm and
Op2 values, however this will be fixed in a later change.
This will be used by ptrace to allow hardware breakpoints in userspace.
Sponsored by: DARPA, AFRL
These instructions are used to access the registers described in armreg.h,
and will be used in a future change to create a per-register identification
macro.
Sponsored by: DARPA, AFRL
The debug monitor register state is now stored in a struct and updated
when required. Currently there is only a kernel state, however a
per-process state will be added in a future change.
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22128
Because of the previous naming scheme the old ID_AA64PFR0_EL1 macro
collided with a potential macro for the register of the same name. To fix
this collision rename these macros.
Sponsored by: DARPA, AFRL
Summary: Add trivial 32-bit arm cores on aarch64 support for gcore. This
doesn't handle fpregs.
Reviewed by: #arm, andrew
Sponsored by: Juniper Networks, Inc
Differential Revision: https://reviews.freebsd.org/D21947
We must also check for large mappings. pmap_page_is_mapped() is
mostly used in assertions, so the problem was not very noticeable.
Reviewed by: alc
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21824
Many extern struct pcpu <something>__pcpu declarations were
copied/pasted in sources. The issue is that the definition is MD, but
it cannot be provided by machine/pcpu.h due to actual struct pcpu
defined in sys/pcpu.h later than the inclusion of machine/pcpu.h.
This forced the copying when other code needed direct access to
__pcpu. There is no way around it, due to machine/pcpu.h supplying
part of struct pcpu fields.
To work around the problem, add a new machine/pcpu_aux.h header, which
should fill any needed MD definitions after struct pcpu definition is
completed. This allows to remove copies of __pcpu spread around the
source. Also on x86 it makes it possible to remove work arounds like
OFFSETOF_CURTHREAD or clang specific warnings supressions.
Reported and tested by: lwhsu, bcran
Reviewed by: imp, markj (previous version)
Discussed with: jhb
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21418
doing so adds more flexibility with less redundant code.
Reviewed by: jhb, markj, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D21250
pmap's lock ensures that other operations on the pmap don't observe the
old mapping being broken before the new mapping is established. However,
pmap_kextract() doesn't acquire the kernel pmap's lock, so it may observe
the broken mapping. And, if it does, it returns an incorrect result.
This revision implements a lock-free solution to this problem in
pmap_update_entry() and pmap_kextract() because pmap_kextract() can't
acquire the kernel pmap's lock.
Reported by: andrew, greg_unrelenting.technology
Reviewed by: andrew, markj
Tested by: greg_unrelenting.technology
X-MFC with: r350579
Differential Revision: https://reviews.freebsd.org/D21169
The ARMv8 reference manual only states that the bit is reserved in
this case; following Linux's example, use it instead of a
software-defined bit for the purpose of indicating that a managed
mapping is writable.
Reviewed by: alc, andrew
MFC after: r350004
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21121
Previously only some of the ID register fields were 64 bit. To allow
for a script to generate these mark them all 64 bit. To allow for their
use in assembly we need to use the UINT64_C macro via a new UL macro
to stop the lines from being too long.
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D20977
Add HWCAP support for arm64.
defines are the same as in Linux and a userland program can use
elf_aux_info to get the data.
We only save the common denominator for all cores in case the
big and little cluster have different support (this is known to
exists even if we don't support those SoCs in FreeBSD)
Differential Revision: https://reviews.freebsd.org/D17137
Previously the arm64 pmap did no reference or modification tracking;
all mappings were treated as referenced and all read-write mappings
were treated as dirty. This change implements software management
of these attributes.
Dirty bit management is implemented to emulate ARMv8.1's optional
hardware dirty bit modifier management, following a suggestion from alc.
In particular, a mapping with ATTR_SW_DBM set is logically writeable and
is dirty if the ATTR_AP_RW_BIT bit is clear. Mappings with
ATTR_AP_RW_BIT set are write-protected, and a write access will trigger
a permission fault. pmap_fault() handles permission faults for such
mappings and marks the page dirty by clearing ATTR_AP_RW_BIT, thus
mapping the page read-write.
Reviewed by: alc
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20907
I just happenned to have 3rd party code using 'var' as the output variable
which drew my attention to this. variables defined inside macros should be
prefixed to avoid getting shadowed varable wanrings from clang.
cpufunc, in terms of __builtin_ffs and the like, for arm64
architectures, and use those, rather than the simple libkern
implementations, in building arm64 kernels.
Tested by: greg_unrelenting.technology (earlier version)
Reviewed by: alc
Approved by: kib (mentor)
Differential Revision: https://reviews.freebsd.org/D20250
In all practical situations, the resolver visibility is static.
Requested by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Approved by: so (emaste)
Differential revision: https://reviews.freebsd.org/D20281
Add the infrastructure to allow MD procctl(2) commands, and use it to
introduce amd64 PTI control and reporting. PTI mode cannot be
modified for existing pmap, the knob controls PTI of the new vmspace
created on exec.
Requested by: jhb
Reviewed by: jhb, markj (previous version)
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D19514
Skylake Xeons.
See SDM rev. 68 Vol 3 4.6.2 Protection Keys and the description of the
RDPKRU and WRPKRU instructions.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D18893
cpu_icache_sync_range(), except that it sets pcb_onfault to catch any page
fault, as doing cache maintenance operations for non-mapped generates a
data abort, and use it in freebsd32_sysarch(), so that a userland program
attempting to sync the icache with unmapped addresses doesn't crash the
kernel.
Spotted out by: andrew
Replace a call to DELAY(1) with a new cpu_lock_delay() KPI. Currently
cpu_lock_delay() is defined to DELAY(1) on all platforms. However,
platforms with a DELAY() implementation that uses spin locks should
implement a custom cpu_lock_delay() doesn't use locks.
Reviewed by: kib
MFC after: 3 days
While here tag which architecture release fields were added and remove a
field that only existed in very early releases of the ARMv8 spec.
Sponsored by: DARPA, AFRL
All platforms except powerpc use the same values and powerpc shares a
majority of them.
Go ahead and declare AT_NOTELF, AT_UID, and AT_EUID in favor of the
unused AT_DCACHEBSIZE, AT_ICACHEBSIZE, and AT_UCACHEBSIZE for powerpc.
Reviewed by: jhb, imp
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D17397
