Get rid of sa->narg. It serves no purpose; use sa->callp->sy_narg instead.

Reviewed by: kib
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D26458

Use uintptr_t instead of register_t * for the stack base.

- Use ustringp for the location of the argv and environment strings
and allow destp to travel further down the stack for the stackgap
an

Use uintptr_t instead of register_t * for the stack base.

- Use ustringp for the location of the argv and environment strings
and allow destp to travel further down the stack for the stackgap
and auxv regions.
- Update the Linux copyout_strings variants to move destp down the
stack as was done for the native ABIs in r263349.
- Stop allocating a space for a stack gap in the Linux ABIs. This
used to hold translated system call arguments, but hasn't been used
since r159992.

Reviewed by: kib
Tested on: md64 (amd64, i386, linux64), i386 (i386, linux)
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D22501

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Remove sv_pagesize, originally introduced with r100384.

In all of the architectures we have today, we always use PAGE_SIZE.
While in theory one could define different things, none of the
current arc

Remove sv_pagesize, originally introduced with r100384.

In all of the architectures we have today, we always use PAGE_SIZE.
While in theory one could define different things, none of the
current architectures do, even the ones that have transitioned from
32-bit to 64-bit like i386 and arm. Some ancient mips binaries on
other systems used 8k instead of 4k, but we don't support running
those and likely never will due to their age and obscurity.

Reviewed by: imp (who also contributed the commit message)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D19280

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Correct some more places where TO_PTR() should be used.

These were missed in r326228.

MFC after: 2 weeks

Use TO_PTR() to convert integers to pointers.

For FreeBSD/arm64's cloudabi32 support, I'm going to need a TO_PTR() in
this place. Also use it for all of the other source files, so that the
differenc

Use TO_PTR() to convert integers to pointers.

For FreeBSD/arm64's cloudabi32 support, I'm going to need a TO_PTR() in
this place. Also use it for all of the other source files, so that the
difference remains as minimal as possible.

MFC after: 2 weeks

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Don't let cpu_set_syscall_retval() clobber exec_setregs().

Upon successful completion, the execve() system call invokes
exec_setregs() to initialize the registers of the initial thread of the
newly

Don't let cpu_set_syscall_retval() clobber exec_setregs().

Upon successful completion, the execve() system call invokes
exec_setregs() to initialize the registers of the initial thread of the
newly executed process. What is weird is that when execve() returns, it
still goes through the normal system call return path, clobbering the
registers with the system call's return value (td->td_retval).

Though this doesn't seem to be problematic for x86 most of the times (as
the value of eax/rax doesn't matter upon startup), this can be pretty
frustrating for architectures where function argument and return
registers overlap (e.g., ARM). On these systems, exec_setregs() also
needs to initialize td_retval.

Even worse are architectures where cpu_set_syscall_retval() sets
registers to values not derived from td_retval. On these architectures,
there is no way cpu_set_syscall_retval() can set registers to the way it
wants them to be upon the start of execution.

To get rid of this madness, let sys_execve() return EJUSTRETURN. This
will cause cpu_set_syscall_retval() to leave registers intact. This
makes process execution easier to understand. It also eliminates the
difference between execution of the initial process and successive ones.
The initial call to sys_execve() is not performed through a system call
context.

Reviewed by: kib, jhibbits
Differential Revision: https://reviews.freebsd.org/D13180

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Move struct syscall_args syscall arguments parameters container into
struct thread.

For all architectures, the syscall trap handlers have to allocate the
structure on the stack. The structure takes

Move struct syscall_args syscall arguments parameters container into
struct thread.

For all architectures, the syscall trap handlers have to allocate the
structure on the stack. The structure takes 88 bytes on 64bit arches
which is not negligible. Also, it cannot be easily found by other
code, which e.g. caused duplication of some members of the structure
to struct thread already. The change removes td_dbg_sc_code and
td_dbg_sc_nargs which were directly copied from syscall_args.

The structure is put into the copied on fork part of the struct thread
to make the syscall arguments information correct in the child after
fork.

This move will also allow several more uses shortly.

Reviewed by: jhb (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 3 weeks
X-Differential revision: https://reviews.freebsd.org/D11080

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Stop providing the compat_3_brand.

As of r315860, the ELF image activator works fine for CloudABI without it.

Reviewed by: kib
MFC after: 2 weeks

Update r315753 with the proper flag name.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week

Add a flag BI_BRAND_ONLY_STATIC to specify that the brand only
matches static binaries.

Interpretation of the 'static' there is that the binary must not
specify an interpreter. In particular, share

Add a flag BI_BRAND_ONLY_STATIC to specify that the brand only
matches static binaries.

Interpretation of the 'static' there is that the binary must not
specify an interpreter. In particular, shared objects are matched by
the brand if BI_CAN_EXEC_DYN is also set.

This improves precision of the brand matching, which should eliminate
surprises due to brand ordering.

Revert r315701.

Discussed with and tested by: ed (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

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Set the interpreter path to /nonexistent.

CloudABI executables are statically linked and don't have an
interpreter. Setting the interpreter path to NULL used to work
previously, but r314851 introduc

Set the interpreter path to /nonexistent.

CloudABI executables are statically linked and don't have an
interpreter. Setting the interpreter path to NULL used to work
previously, but r314851 introduced code that checks the string
unconditionally. Running CloudABI executables now causes a null pointer
dereference.

Looking at the rest of imgact_elf.c, it seems various other codepaths
already leaned on the fact that the interpreter path is set. Let's just
go ahead and pick an obviously incorrect interpreter path to appease
imgact_elf.c.

MFC after: 1 week

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Catch up with changes to structure member names.

Pointer/length pairs are now always named ${name} and ${name}_len.

Convert pointers obtained from the threadattr_t structure with TO_PTR().

In all of these source files, the userspace pointer size corresponds
with the kernelspace pointer size, meaning that casting

Convert pointers obtained from the threadattr_t structure with TO_PTR().

In all of these source files, the userspace pointer size corresponds
with the kernelspace pointer size, meaning that casting directly works.
As I'm planning on making 32-bit execution on 64-bit systems work as
well, use TO_PTR() here as well, so that the changes between source
files remain minimal.

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Provide the CloudABI vDSO to its executables.

CloudABI executables already provide support for passing in vDSOs. This
functionality is used by the emulator for OS X to inject system call
handlers. O

Provide the CloudABI vDSO to its executables.

CloudABI executables already provide support for passing in vDSOs. This
functionality is used by the emulator for OS X to inject system call
handlers. On FreeBSD, we could use it to optimize calls to
gettimeofday(), etc.

Though I don't have any plans to optimize any system calls right now,
let's go ahead and already pass in a vDSO. This will allow us to
simplify the executables, as the traditional "syscall" shims can be
removed entirely. It also means that we gain more flexibility with
regards to adding and removing system calls.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D7438

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Don't forget to set sa->narg for CloudABI system calls.

It turns out that this value is not used within the system call code
under normal conditions, except when using tracing tools like ktrace.
If

Don't forget to set sa->narg for CloudABI system calls.

It turns out that this value is not used within the system call code
under normal conditions, except when using tracing tools like ktrace.
If we forget to set this value, it is set to random garbage. This may
cause ktrace to hang indefinitely, making it impossible to kill.

Reported by: Michael Plass
PR: 210800
MFC before: 11.0-RELEASE

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Update comments for the MD functions managing contexts for new
threads, to make it less confusing and using modern kernel terms.

Rename the functions to reflect current use of the functions, instead

Update comments for the MD functions managing contexts for new
threads, to make it less confusing and using modern kernel terms.

Rename the functions to reflect current use of the functions, instead
of the historic KSE conventions:
cpu_set_fork_handler -> cpu_fork_kthread_handler (for kthreads)
cpu_set_upcall -> cpu_copy_thread (for forks)
cpu_set_upcall_kse -> cpu_set_upcall (for new threads creation)

Reviewed by: jhb (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Approved by: re (hrs)
Differential revision: https://reviews.freebsd.org/D6731

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Make CloudABI's way of doing TLS more friendly to userspace emulators.

We're currently seeing how hard it would be to run CloudABI binaries on
operating systems cannot be modified easily (Windows, M

Make CloudABI's way of doing TLS more friendly to userspace emulators.

We're currently seeing how hard it would be to run CloudABI binaries on
operating systems cannot be modified easily (Windows, Mac OS X). The
idea is that we want to just run them without any sandboxing. Now
that CloudABI executables are PIE, this is already a bit easier, but TLS
is still problematic:

- CloudABI executables want to write to the %fs, which typically
requires extra system calls by the emulator every time it needs to
switch between CloudABI's and its own TLS.

- If CloudABI executables overwrite the %fs base unconditionally, it
also becomes harder for the emulator to store a backup of the old
value of %fs. To solve this, let's no longer overwrite %fs, but just
%fs:0.

As CloudABI's C library does not use a TCB, this space can now be used
by an emulator to keep track of its internal state. The executable can
now safely overwrite %fs:0, as long as it makes sure that the TCB is
copied over to the new TLS area.

Ensure that there is an initial TLS area set up when the process starts,
only containing a bogus TCB. We don't really care about its contents on
FreeBSD.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D5836

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Make Position Independent Executables work for CloudABI.

- Set BI_CAN_EXEC_DYN, so we can execute ET_DYN ELF files in addition to
regular ET_EXECs.
- Provide an AT_BASE entry in the auxiliary vect

Make Position Independent Executables work for CloudABI.

- Set BI_CAN_EXEC_DYN, so we can execute ET_DYN ELF files in addition to
regular ET_EXECs.
- Provide an AT_BASE entry in the auxiliary vector, so the executable
knows at which address it got loaded and can apply relocations.

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Fix reporting of the CloudABI ABI in kdump.

- Advertise the word size for CloudABI ABIs via the SV_LP64 flag. All of
the other ABIs include either SV_ILP32 or SV_LP64.
- Fix kdump to not assume a

Fix reporting of the CloudABI ABI in kdump.

- Advertise the word size for CloudABI ABIs via the SV_LP64 flag. All of
the other ABIs include either SV_ILP32 or SV_LP64.
- Fix kdump to not assume a 32-bit ABI if the ABI flags field is non-zero
but SV_LP64 isn't set. Instead, only assume a 32-bit ABI if SV_ILP32 is
set and fallback to the unknown value of "00" if neither SV_LP64 nor
SV_ILP32 is set.

Reviewed by: kib, ed
Differential Revision: https://reviews.freebsd.org/D5560

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As <machine/pmap.h> is included from <vm/pmap.h>, there is no need to
include it explicitly when <vm/pmap.h> is already included.

Reviewed by: alc, kib
Differential Revision: https://reviews.freebsd

As <machine/pmap.h> is included from <vm/pmap.h>, there is no need to
include it explicitly when <vm/pmap.h> is already included.

Reviewed by: alc, kib
Differential Revision: https://reviews.freebsd.org/D5373

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Add support for CloudABI on ARM64.

It turns out that it is pretty easy to make CloudABI work on ARM64. We
essentially only need to copy over the sysvec from AMD64 and ensure that
we use ARM64 specif

Add support for CloudABI on ARM64.

It turns out that it is pretty easy to make CloudABI work on ARM64. We
essentially only need to copy over the sysvec from AMD64 and ensure that
we use ARM64 specific registers.

As there is an overlap between function argument and return registers,
we do need to extend cloudabi64_schedtail() to only set its values if
we're actually forking. Not when we're creating a new thread.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D3917

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