This register set contains the values of the fsbase and gsbase
registers. Note that these registers can already be controlled
individually via ptrace(2) via MD operations, so the main reason for
adding this is to include these register values in core dumps. In
particular, this will enable looking up the value of TLS variables
from core dumps in gdb.
The value of NT_X86_SEGBASES was chosen to match the value of
NT_386_TLS on Linux. The notes serve similar purposes, but FreeBSD
will never dump a note equivalent to NT_386_TLS (which dumps a single
segment descriptor rather than a pair of addresses) and picking a
currently-unused value in the NT_X86_* range could result in a future
conflict.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D34650
Introduce a helper to fetch the TSC frequency from CPUID when running
under Xen.
Since the TSC can also be initialized early when running as a Xen
guest pull out the call to tsc_init() from the
early_clock_source_init() handlers and place it in clock_init(), as
otherwise all handlers would call tsc_init() anyway.
Reviewed by: markj
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D34581
This lets us use the TSC to implement early DELAY, limiting the use of
the sometimes-unreliable 8254 PIT.
PR: 262155
Reviewed by: emaste
Tested by: emaste, mike tancsa <mike@sentex.net>, Stefan Hegnauer <stefan.hegnauer@gmx.ch>
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34367
In a subsequent commit clock_init() will attempt to determine the TSC
frequency, and this requires that CPU identification is finalized.
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Add a static assert for the siginfo_t, mcontext_t and ucontext_t
sizes. These are de-facto ABI options and cannot change size ever.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D34211
These headers originate with the Xen project and shouldn't be mixed with
the main portion of the FreeBSD kernel. Notably they shouldn't be the
target of clean-up commits.
Switch to use the headers in sys/contrib/xen.
Reviewed by: royger
Modules no longer call kernel functions for atomic ops, and since the
previous commit, we always use lock prefix.
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: jhb, markj
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D34153
Atomics have significant other use besides providing in-system
primitives for safe memory updates. They are used for implementing
communication with out of system software or hardware following some
protocols.
For instance, even UP kernel might require a protocol using atomics to
communicate with the software-emulated device on SMP hypervisor. Or
real hardware might need atomic accesses as part of the proper
management protocol.
Another point is that UP configurations on x86 are extinct, so slight
performance hit by unconditionally use proper atomics is not important.
It is compensated by less code clutter, which in fact improves the
UP/i386 lifetime expectations.
Requested by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: Elliott Mitchell, imp, jhb, markj, royger
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D34153
This adds the PT_GETREGSET and PT_SETREGSET ptrace types. These can be
used to access all the registers from a specified core dump note type.
The NT_PRSTATUS and NT_FPREGSET notes are initially supported. Other
machine-dependant types are expected to be added in the future.
The ptrace addr points to a struct iovec pointing at memory to hold the
registers along with its length. On success the length in the iovec is
updated to tell userspace the actual length the kernel wrote or, if the
base address is NULL, the length the kernel would have written.
Because the data field is an int the arguments are backwards when
compared to the Linux PTRACE_GETREGSET call.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19831
The approach taken by the stack gap implementation was to insert a
random gap between the top of the fixed stack mapping and the true top
of the main process stack. This approach was chosen so as to avoid
randomizing the previously fixed address of certain process metadata
stored at the top of the stack, but had some shortcomings. In
particular, mlockall(2) calls would wire the gap, bloating the process'
memory usage, and RLIMIT_STACK included the size of the gap so small
(< several MB) limits could not be used.
There is little value in storing each process' ps_strings at a fixed
location, as only very old programs hard-code this address; consumers
were converted decades ago to use a sysctl-based interface for this
purpose. Thus, this change re-implements stack address randomization by
simply breaking the convention of storing ps_strings at a fixed
location, and randomizing the location of the entire stack mapping.
This implementation is simpler and avoids the problems mentioned above,
while being unlikely to break compatibility anywhere the default ASLR
settings are used.
The kern.elfN.aslr.stack_gap sysctl is renamed to kern.elfN.aslr.stack,
and is re-enabled by default.
PR: 260303
Reviewed by: kib
Discussed with: emaste, mw
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33704
Rather than fetching the ps_strings address directly from a process'
sysentvec, use this macro. With stack address randomization the
ps_strings address is no longer fixed.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33704
The size of the ps_strings structure varies between ABIs, so this is
useful for computing the address of the ps_strings structure relative to
the top of the stack when stack address randomization is enabled.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33704
Requested by: kib
Reviewed by: brooks, imp, kib
Sponsored by: The University of Cambridge, Google Inc.
Differential Revision: https://reviews.freebsd.org/D33886
This matches the recent renaming of struct freebsd4_ucontext.
Reviewed by: brooks, imp, kib
Sponsored by: The University of Cambridge, Google Inc.
Differential Revision: https://reviews.freebsd.org/D33880
Missed issues in truss on at least armv7 and powerpcspe need to be
resolved before recommit.
This reverts commit 3889fb8af0.
This reverts commit 1544e0f5d1.
Simplify control flow around handling of the execpath length and signal
trampoline. Cache the sysentvec pointer in a local variable.
No functional change intended.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33703
The introduction of <sched.h> improved compatibility with some 3rd
party software, but caused the configure scripts of some ports to
assume that they were run in a GLIBC compatible environment.
Parts of sched.h were made conditional on -D_WITH_CPU_SET_T being
added to ports, but there still were compatibility issues due to
invalid assumptions made in autoconfigure scripts.
The differences between the FreeBSD version of macros like CPU_AND,
CPU_OR, etc. and the GLIBC versions was in the number of arguments:
FreeBSD used a 2-address scheme (one source argument is also used as
the destination of the operation), while GLIBC uses a 3-adderess
scheme (2 source operands and a separately passed destination).
The GLIBC scheme provides a super-set of the functionality of the
FreeBSD macros, since it does not prevent passing the same variable
as source and destination arguments. In code that wanted to preserve
both source arguments, the FreeBSD macros required a temporary copy of
one of the source arguments.
This patch set allows to unconditionally provide functions and macros
expected by 3rd party software written for GLIBC based systems, but
breaks builds of externally maintained sources that use any of the
following macros: CPU_AND, CPU_ANDNOT, CPU_OR, CPU_XOR.
One contributed driver (contrib/ofed/libmlx5) has been patched to
support both the old and the new CPU_OR signatures. If this commit
is merged to -STABLE, the version test will have to be extended to
cover more ranges.
Ports that have added -D_WITH_CPU_SET_T to build on -CURRENT do
no longer require that option.
The FreeBSD version has been bumped to 1400046 to reflect this
incompatible change.
Reviewed by: kib
MFC after: 2 weeks
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D33451
When a DMA request using bounce pages completes, a swi is triggered to
schedule pending DMA requests using the just-freed bounce pages. For
a long time this bus_dma swi has been tied to a "virtual memory" swi
(swi_vm). However, all of the swi_vm implementations are the same and
consist of checking a flag (busdma_swi_pending) which is always true
and if set calling busdma_swi. I suspect this dates back to the
pre-SMPng days and that the intention was for swi_vm to serve as a
mux. However, in the current scheme there's no need for the mux.
Instead, remove swi_vm and vm_ih. Each bus_dma implementation that
uses bounce pages is responsible for creating its own swi (busdma_ih)
which it now schedules directly. This swi invokes busdma_swi directly
removing the need for busdma_swi_pending.
One consequence is that the swi now works on RISC-V which had previously
failed to invoke busdma_swi from swi_vm.
Reviewed by: imp, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D33447
Notably, the current compat_options only makes sense for native and
freebsd32 ABIs. For the others, it just adds cruft. Switch to having
sets of compat options, and default to the native set. Setup the other
ABIs where it doesn't make sense to opt-out of the native set.
This removes some redundant COMPAT_FREEBSD* stuff from Linuxolator bits.
line_expr in makesyscalls.lua is fixed to allow empty strings to be
specified, since they're harmless.
Reviewed by: brooks, kib (both earlier version)
Differential Revision: https://reviews.freebsd.org/D33356
Suggested by: Michael Pratt <mpratt@google.com>
Reviewed by: Michael Pratt <mpratt@google.com>, emaste
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Differential revision: https://reviews.freebsd.org/D33423
The header exports the following:
- Definition of struct tcb.
- Helpers to get/set the tcb for the current thread.
- TLS_TCB_SIZE (size of TCB)
- TLS_TCB_ALIGN (alignment of TCB)
- TLS_VARIANT_I or TLS_VARIANT_II
- TLS_DTV_OFFSET (bias of pointers in dtv[])
- TLS_TP_OFFSET (bias of "thread pointer" relative to TCB)
Note that TLS_TP_OFFSET does not account for if the unbiased thread
pointer points to the start of the TCB (arm and x86) or the end of the
TCB (MIPS, PowerPC, and RISC-V).
Note also that for amd64, the struct tcb does not include the unused
tcb_spare field included in the current structure in libthr. libthr
does not use this field, and the existing calls in libc and rtld that
allocate a TCB for amd64 assume it is the size of 3 Elf_Addr's (and
thus do not allocate room for tcb_spare).
A <sys/_tls_variant_i.h> header is used by architectures using
Variant I TLS which uses a common struct tcb.
Reviewed by: kib (older version of x86/tls.h), jrtc27
Sponsored by: The University of Cambridge, Google Inc.
Differential Revision: https://reviews.freebsd.org/D33351
After a round of cleanups in late 2020, all definitions are
functionally identical.
This removes a rotted __aligned(8) on arm. It was added in
b7112ead32 and was intended to align the
args member so that 64-bit types (off_t, etc) could be safely read on
armeb compiled with clang. With the removal of armev, this is no
longer needed (armv7 requires that 32-bit aligned reads of 64-bit
values be supported and we enable such support on armv6). As further
evidence this is unnecessary, cleanups to struct syscall_args have
resulted in args being 32-bit aligned on 32-bit systems. The sole
effect is to bloat the struct by 4 bytes.
Reviewed by: kib, jhb, imp
Differential Revision: https://reviews.freebsd.org/D33308
The headers were mostly identical on amd64 and i386.
No functional change intended.
Reviewed by: cperciva, mav, imp, kib, jhb
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33205
It stopped being used in 3c256f5395, when trap() was reorganized to
have separate switch statements for user and kernel traps. Remove the
two leftover references and the flag itself.
Reviewed by: kib
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D33253
On this platform, the pcb and FPU save area are allocated from the top
of each kernel stack, so they should be excluded from the calculation of
the total and used stack sizes.
Reviewed by: kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32581
The vga and splash devices are part of the sc(4) system console. vt(4)
uses the vt_vga driver instead, and has some limited splash support
directly in vt_core.c. Leave the sc(4) options in GENERIC/MINIMAL (for
now) but group them together under an sc(4) comment.
Sponsored by: The FreeBSD Foundation
Followup to b8cf1c5c30, remove from MINIMAL in addition to GENERIC.
options VESA / vesa.ko provides VESA Bios Extensions (VBE) support for
the legacy sc(4) console. It is not used by the default console, vt(4).
PR: 253733
Fixes: b8cf1c5c30 ("Remove options VESA from x86 GENERIC")
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
options VESA / vesa.ko provides VESA Bios Extensions (VBE) support for
the legacy sc(4) console. It is not used by the default console, vt(4).
There is a report[1] of an incompatibility between VESA and the Nvidia
driver breaking suspend/resume. Since VESA is not used by the default
configuration anyway, just remove options VESA from GENERIC. The kernel
module is still available and may be loaded by sc(4) users who want to
select a VBE mode.
(Note that vt(4) does not support selecting a VBE mode. The loader can
set a VBE mode and vt(4) will use it via the vt_vbefb driver.)
[1] https://lists.freebsd.org/archives/freebsd-hackers/2021-November/000469.html
PR: 253733
Reported by: Stefan Blachmann [1]
Reviewed by: imp, manu, tsoome
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33141
Belatedly remove twa(4). It was supposed to go before 13.0, but was
overlooked.
Sponsored by: Netflix
Relnotes: yes
Reviewed by: scottl
Differential Revision: https://reviews.freebsd.org/D33114
Belatedly remove esp(4). It was tagged as gone in 13, but was overlooked
until now.
Sponsored by: Netflix
Reviewed by: scottl
Differential Revision: https://reviews.freebsd.org/D33115
Belatedly remove amr(4). It was slated to depart before 13.0 but was
overlooked until now.
Sponsored by: Netflix
Relnotes: yes
Reviewed by: scottl
Differential Revision: https://reviews.freebsd.org/D33113
Belatedly remove iir(4). It was slated to go before 13, but was
overlooked.
Sponsored by: Netflix
Relnotes: yes
Reviewed by: scottl
Differential Revision: https://reviews.freebsd.org/D33112
We'd said this was going away in 13, but was overlooked. Belatedly
remove.
Sponsored by: Netflix
Relnotes: yes
Reviewed by: scottl
Differential Revision: https://reviews.freebsd.org/D33111
