This definition enables callers to estimate remaining space on the
kstack, and take action on it. Notably, it enables optimizations in the
GEOM and netgraph subsystems to directly dispatch work items when there
is sufficient stack space, rather than queuing them for a worker thread.
Implement it for riscv, arm, and mips. Remove the #ifdefs, so it will
not go unimplemented elsewhere.
PR: 259157
Reviewed by: mav, kib, markj (previous version)
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32580
It was never implemented on powerpc or riscv and appears to have been
unused since it was added in 1998. No functional change intended.
Reviewed by: kp, glebius, cy
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33093
The minidump code is written assuming that certain global state will not
change, and rightly so, since it executes from a kernel debugger
context. In order to support taking minidumps of a live system, we
should allow copies of relevant global state that is likely to change to
be passed as parameters to the minidumpsys() function.
This patch does the work of parameterizing this function, by adding a
struct minidumpstate argument. For now, this struct allows for copies of
the kernel message buffer, and the bitset that tracks which pages should
be dumped (vm_page_dump). Follow-up changes will actually make use of
these arguments.
Notably, dump_avail[] does not need a snapshot, since it is not expected
to change after system initialization.
The existing minidumpsys() definitions are renamed, and a thin MI
wrapper is added to kern_dump.c, which handles the construction of
the state struct. Thus, calling minidumpsys() remains as simple as
before.
Reviewed by: kib, markj, jhb
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D31989
The implementation of the progress bar is simple, but duplicated for
most minidump implementations. Extract the common bits to kern_dump.c.
Ensure that the bar is reset with each subsequent dump; this was only
done on some platforms previously.
Reviewed by: markj
MFC after: 2 weeks
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D31885
Move the common kernel function signatures from machine/reg.h to a new
sys/reg.h. This is in preperation for adding PT_GETREGSET to ptrace(2).
Reviewed by: imp, markj
Sponsored by: DARPA, AFRL (original work)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19830
These ones were unambiguous cases where the Foundation was the only
listed copyright holder (in the associated license block).
Sponsored by: The FreeBSD Foundation
which is the place to put MD asserts about allocated pages.
On amd64, verify that allocated page does not belong to the kernel
(text, data) or early allocated pages.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31121
The syscall number is stored in the same register as the syscall return
on amd64 (and possibly other architectures) and so it is impossible to
recover in the signal handler after the call has returned. This small
tweak delivers it in the `si_value` field of the signal, which is
sufficient to catch capability violations and emulate them with a call
to a more-privileged process in the signal handler.
This reapplies 3a522ba1bc with a fix for
the static assertion failure on i386.
Approved by: markj (mentor)
Reviewed by: kib, bcr (manpages)
Differential Revision: https://reviews.freebsd.org/D29185
The syscall number is stored in the same register as the syscall return
on amd64 (and possibly other architectures) and so it is impossible to
recover in the signal handler after the call has returned. This small
tweak delivers it in the `si_value` field of the signal, which is
sufficient to catch capability violations and emulate them with a call
to a more-privileged process in the signal handler.
Approved by: markj (mentor)
Reviewed by: kib, bcr (manpages)
Differential Revision: https://reviews.freebsd.org/D29185
Many of these typedefs are the same across all architectures or can
be set based on an architecture-independent compiler-provided macro
(e.g. __SIZEOF_SIZE_T__). These macros have been available since GCC 4.6
and Clang sometime before 3.0 (godbolt.org does not have any older clang
versions installed).
I originally considered using the compiler-provided `__FOO_TYPE__` directly.
However, in order to do so we have to check that those match the previous
typedef exactly (not just that they have the same size) since any change
would be an ABI break. For example, changing `long` to `long long` results
in different C++ name mangling. Additionally, Clang and GCC disagree on
the underlying type for some of (u)int*_fast_t types, so this change
only moves the definitions that are identical across all architectures
and does not touch those types.
This de-deduplication will allow us to have a smaller diff downstream in
CheriBSD: we only have to only change the (u)intptr_t definition in
sys/_types.h in CheriBSD instead of having to change machine/_types.h for
all CHERI-enabled architectures (currently RISC-V, AArch64 and MIPS).
Reviewed By: imp, kib
Differential Revision: https://reviews.freebsd.org/D29895
This is intended to be used with memory mapped IO, e.g. from
bus_space_map with no flags, or pmap_mapdev.
Use this new memory type in the map request configured by
resource_init_map_request, and in pciconf.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D29692
--Eliminate a big ifdef that encompassed all currently-supported
architectures except mips and powerpc32. This applied to the case
in which we've allocated a superpage but the pager-populated range
is insufficient for a superpage mapping. For platforms that don't
support superpages the check should be inexpensive as we shouldn't
get a superpage in the first place. Make the normal-page fallback
logic identical for all platforms and provide a simple implementation
of pmap_ps_enabled() for MIPS and Book-E/AIM32 powerpc.
--Apply the logic for handling pmap_enter() failure if a superpage
mapping can't be supported due to additional protection policy.
Use KERN_PROTECTION_FAILURE instead of KERN_FAILURE for this case,
and note Intel PKU on amd64 as the first example of such protection
policy.
Reviewed by: kib, markj, bdragon
Differential Revision: https://reviews.freebsd.org/D29439
The remote protocol allows for implementations to report more specific
reasons for the break in execution back to the client [1]. This is
entirely optional, so it is only implemented for amd64, arm64, and i386
at the moment.
[1] https://sourceware.org/gdb/current/onlinedocs/gdb/Stop-Reply-Packets.html
Reviewed by: jhb
MFC after: 3 weeks
Sponsored by: NetApp, Inc.
Sponsored by: Klara, Inc.
NetApp PR: 51
Differential Revision: https://reviews.freebsd.org/D29174
This basically mirrors what already exists in ddb, but provides a
slightly improved interface. It allows the caller to specify the
watchpoint access type, and returns more specific error codes to
differentiate failure cases.
This will be used to support hardware watchpoints in gdb(4).
Stubs are provided for architectures lacking hardware watchpoint logic
(mips, powerpc, riscv), while other architectures are added individually
in follow-up commits.
Reviewed by: jhb, kib, markj
MFC after: 3 weeks
Sponsored by: NetApp, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D29155
This change serves two purposes.
First, we take advantage of the compiler provided endian definitions to
eliminate some long-standing duplication between the different versions
of this header. __BYTE_ORDER__ has been defined since GCC 4.6, so there
is no need to rely on platform defaults or e.g. __MIPSEB__ to determine
endianness. A new common sub-header is added, but there should be no
changes to the visibility of these definitions.
Second, this eliminates the hand-rolled __bswapNN() routines, again in
favor of the compiler builtins. This was done already for x86 in
e6ff6154d2. The benefit here is that we no longer have to maintain our
own implementations on each arch, and can instead rely on the compiler
to emit appropriate instructions or libcalls, as available. This should
result in equivalent or better code generation. Notably 32-bit arm will
start using the `rev` instruction for these routines, which is available
on armv6+.
PR: 236920
Reviewed by: arichardson, imp
Tested by: bdragon (BE powerpc)
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D29012
e4b8deb222 removed the last in-tree uses of PCPU_INC(). Its
potential benefit is also practically nonexistent. Non-x86
platforms already implement it as PCPU_ADD(..., 1), and according
to [0] there are no recent x86 processors for which the 'inc'
instruction provides a performance benefit over the equivalent
memory-operand form of the 'add' instruction. The only remaining
benefit of 'inc' is smaller instruction size, which in this case
is inconsequential given the limited number of per-CPU data consumers.
[0]: https://www.agner.org/optimize/instruction_tables.pdf
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D29308
While here, use MAXARGS. This brings its 'struct syscall_args' in sync
with most other architectures.
Reviewed by: arichardson, brooks
MFC after: 2 weeks
Sponsored by: EPSRC
Differential Revision: https://reviews.freebsd.org/D26619
There may be additional 64-bit ABIs supported, so use a positive check rather
than a negative check.
Suggested by: imp
MFC after: 1 week
Sponsored by: Juniper Networks, Inc
Summary:
Two bugs:
* Elf32_Auxinfo is broken, using pointers in the union, which are 64-bits not
32.
* freebsd32_sysarch() doesn't update the 'user local' register when handling
MIPS_SET_TLS, leading to a NULL pointer dereference in the 32-bit
application.
Reviewed by: #mips, brooks
MFC after: 1 week
Sponsored by: Juniper Networks, Inc
Differential Revision: https://reviews.freebsd.org/D26556
On Ampere Altra systems, the sparse population of RAM within the
physical address space causes the vm_page_dump bitmap to be much
larger than necessary, increasing the size from ~8 Mib to > 2 Gib
(and overflowing `int` for the size).
Changing the page dump bitmap also changes the minidump file
format, so changes are also necessary in libkvm.
Reviewed by: jhb
Approved by: scottl (implicit)
MFC after: 1 week
Sponsored by: Ampere Computing, Inc.
Differential Revision: https://reviews.freebsd.org/D26131
These definitions were repeated by all architectures, with small
variations. Consolidate the common definitons in machine
independent code and use bitset(9) macros for manipulation. Many
opportunities for deduplication remain in the machine dependent
minidump logic. The only intended functional change is increasing
the bit index type to vm_pindex_t, allowing the indexing of pages
with address of 8 TiB and greater.
Reviewed by: kib, markj
Approved by: scottl (implicit)
MFC after: 1 week
Sponsored by: Ampere Computing, Inc.
Differential Revision: https://reviews.freebsd.org/D26129
One problem with the bus_space_read_N() and bus_space_write_N() family of
functions is that they provide no protection against exceptions which can
occur when no physical hardware or device responds to the read or write
cycles. In such a situation, the system typically would panic due to a
kernel-mode bus error. The bus_space_peek_N() and bus_space_poke_N() family
of functions provide a mechanism to handle these exceptions gracefully
without the risk of crashing the system.
Typical example is access to PCI(e) configuration space in bus enumeration
function on badly implemented PCI(e) root complexes (RK3399 or Neoverse
N1 N1SDP and/or access to PCI(e) register when device is in deep sleep state.
This commit adds a real implementation for arm64 only. The remaining
architectures have bus_space_peek()/bus_space_poke() emulated by using
bus_space_read()/bus_space_write() (without exception handling).
MFC after: 1 month
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D25371
This allows privileged userspace processes to find information about the
physical page backing a given mapping. It is useful in applications
such as DPDK which perform some of their own memory management.
Reviewed by: kib, jhb (previous version)
MFC after: 2 weeks
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara Inc.
Differential Revision: https://reviews.freebsd.org/D26237
- Clear the current thread's TLS pointer on exec. Previously the TLS
pointer (and register) remain unchanged.
- Explicitly clear the TLS pointer when new threads are created.
- Make md_tls_tcb_offset per-process instead of per-thread.
The layout of the TLS and TCB are identical for all threads in a
process, it is only the TLS pointer values themselves that vary by
thread. This also makes setting md_tls_tcb_offset in
cpu_set_user_tls() redundant with the setting in exec_setregs(), so
only set it in exec_setregs().
Submitted by: Alfredo Mazzinghi (1)
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24957
Match other architectures and print CPU information during
cpu_startup(). In particular, this prints the information after the
message buffer is initialized which allows it to be retrieved after
boot via dmesg(8).
While here, add some extern declarations to <machine/md_var.h> in
place of duplicated declarations in various source files.
Reviewed by: brooks
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24936
Rather than walking all of cpu_switch looking for the sequence of
instructions to patch, add a global label at the location that needs
the patch applied.
Reviewed by: brooks, Alfredo Mazzinghi <alfredo.mazzinghi_cl.cam.ac.uk>
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24931
The use of "int" here caused the compiler to believe that it needs to
insert a "sll $n, $n, 0" to sign extend as part of the implicit cast
to uint64_t.
Submitted by: Nathaniel Filardo <nwf20@cl.cam.ac.uk>
Reviewed by: brooks, arichardson
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24457
This is a lock-based emulation of 64-bit atomics for kernel use, split off
from an earlier patch by jhibbits.
This is needed to unblock future improvements that reduce the need for
locking on 64-bit platforms by using atomic updates.
The implementation allows for future integration with userland atomic64,
but as that implies going through sysarch for every use, the current
status quo of userland doing its own locking may be for the best.
Submitted by: jhibbits (original patch), kevans (mips bits)
Reviewed by: jhibbits, jeff, kevans
Differential Revision: https://reviews.freebsd.org/D22976
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
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.
Most of this diff is refactoring to reduce duplication between the different
acq_ and rel_ variants.
Differential Revision: https://reviews.freebsd.org/D21822
For ll/sc architectures, atomic(9) allows failure modes where *old == val
due to write failure and callers should compensate for this. Do not retry on
failure, just leave 0 in ret and fail the operation if we couldn't sc it.
This lets the caller determine if it should retry or not.
Reviewed by: kib
Looks ok: imp
Differential Revision: https://reviews.freebsd.org/D21836
This is derived from similar work done in r310481 for i386 and r312610 for
armv6/armv7. Additionally, use a critical section to keep the thread
pinned for per-CPU operations instead of completely disabling local interrupts.
No objections from: adrian, jmallett, imp
Differential Revision: https://reviews.freebsd.org/D18593
The symbol version for _mcount was removed 12 years ago in r169525 from
gmon/Symbol.map, to be added to the per-arch Symbol.map. mips was overlooked
in this, so _mcount has no symver. Add it back to where it should have been,
rather than where it would go if it were added today, since we're correcting
a historical mistake.
Additionally, _mcount is getting thrown into .mdebug.abi32 in the llvm80/90
world as it's not getting explicitly thrown into .text, so do this now. This
fixes the libc build that was previously failing due to relocations in
.mdebug.abi32. This is specifically due to the way clang's integrated AS
works and that they emit the .mdebug.abiNN section early in the process. An
LLVM bug has been submitted[0] and an agreement has been made that the
mips backend should switch to .text following .mdebug.abiNN for
compatibility.
[0] https://bugs.llvm.org/show_bug.cgi?id=43119
Reviewed by: imp, arichardson
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21435
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
machine/regnum.h ends up being included by sys/procfs.h and sys/ptrace.h via
machine/reg.h. Many of the regnum definitions are too short and too generic
to be exposing to any userland application including one of these two
headers. Moreover, these actively cause build failures in googletest
(template <typename T1 ...> expanding to template <typename 9 ...>).
Hide the definitions behind _KERNEL or _WANT_MIPS_REGNUM, and patch all of
the userland consumers to define as needed.
Discussed with: imp, jhb
Reviewed by: imp, jhb
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21330
doing so adds more flexibility with less redundant code.
Reviewed by: jhb, markj, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D21250