With clang 15, the following -Werror warning is produced:
sys/cddl/dev/dtrace/riscv/dtrace_subr.c:165:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_gethrtime()
^
void
This is because dtrace_gethrtime() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
With clang 15, the following -Werror warning is produced:
sys/cddl/dev/dtrace/powerpc/dtrace_subr.c:237:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_gethrtime()
^
void
This is because dtrace_gethrtime() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
With clang 15, the following -Werror warning is produced:
sys/cddl/dev/dtrace/arm/dtrace_subr.c:174:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_gethrtime()
^
void
This is because dtrace_gethrtime() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
Here, the provider is responsible for updating the trapframe to redirect
control flow and for computing the return address. Once software-saved
registers are restored, the emulation shifts the remaining context down
on the stack to make space for the return address, then copies the
address provided by the invop handler. dtrace_invop() is modified to
allocate temporary storage space on the stack for use by the provider to
return the return address.
This is to support a new provider for amd64 which can instrument
arbitrary instructions, not just function entry and exit instructions as
FBT does.
In collaboration with: christos
Sponsored by: Google, Inc. (GSoC 2022)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
dtrace invop handlers have access to the whole trapframe, just use that
to extract %rax/%eax for return probes instead of relying on an
additional parameter to the handler. No functional change intended.
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
With clang 15, the following -Werror warning is produced:
sys/cddl/dev/fbt/fbt.c:1273:11: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
fbt_unload()
^
void
This is because fbt_unload() is declared with a (void) argument list,
but defined with an empty argument list. Make the definition match the
declaration.
MFC after: 3 days
With clang 15, the following -Werror warnings is produced:
sys/cddl/dev/prototype.c:99:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
prototype_unload()
^
void
This is because prototype_unload() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
With clang 15, the following -Werror warnings is produced:
In file included from sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c:18440:
sys/cddl/dev/dtrace/dtrace_unload.c:26:14: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_unload()
^
void
This is because dtrace_unload() is declared with a (void) argument list,
but defined with an empty argument list. Make the definition match the
declaration.
MFC after: 3 days
With clang 15, the following -Werror warnings is produced:
sys/cddl/dev/profile/profile.c:640:15: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
profile_unload()
^
void
This is because profile_unload() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
With clang 15, the following -Werror warnings is produced:
sys/cddl/dev/dtmalloc/dtmalloc.c:177:16: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtmalloc_unload()
^
void
This is because dtmalloc_unload() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
The general aim in this and subsequent patches is to minimize the
amount of code that directly references CTF types such as ctf_type_t,
ctf_array_t, etc. To that end, introduce some routines similar to the
existing fbt_get_ctt_size() (which exists to deal with differences
between v1 and v2) and change ctf_lookup_by_id() to return a void
pointer.
Support for v2 containers is preserved.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34361
The Branch Target Identification (BTI) Armv8-A extension adds new
instructions that can be placed where we may indirrectly branch to,
e.g. at the start of a function called via a function pointer. We can't
emulate these in DTrace as the kernel will have raised a different
exception before the DTrace handler has run.
Skip over the BTI instruction if it's used as the first instruction in
a function.
Sponsored by: The FreeBSD Foundation
We had a hardcoded limit of 1/128-th of physical memory that was further
subdivided between all CPUs as principal buffers are allocated on the
per-CPU basis. Actually, the buffers could use up 1/64-th of the
memmory because with the default switch policy there are two buffers per
CPU.
This commit allows to change that limit.
Note that the discussed limit is per dtrace command invocation.
The idea is to limit the size of a single malloc(9) call, not the total
memory size used by DTrace buffers.
Reviewed by: markj
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D33648
As with arm and riscv fix return fbt probes on arm64. arg0 should be
the offset within the function of the return instruction and arg1
should be the return value.
Reviewed by: kp, markj
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33440
When writing to memory on arm64 we may be trying to be accessing a
read-only page. In this case try to access via the DMAP region to
get a writable location.
While here simplify writing data in DDB and stop trashing the size as
it is passed into the cache handling functions.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32053
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
This was ported from illumos but not completely done. Currently we do
not perform type deduplication between KLDs and the kernel, i.e., kernel
modules have a complete type graph. So, remove it for now since it's
not functional and complicates the task of modifying various CTF type
definitions, and we are hitting some limits in the current format which
necessitate an update.
No functional change intended.
MFC after: 2 weeks
In both cases, too few frames were trimmed, leading to exception handling
or DTrace internals being exposed in stack traces exposed by D's stack()
primitive.
MFC after: 3 days
Reviewed by: emaste, andrew
To trace leaf asm functions we can insert a single nop instruction as
the first instruction in a function and trigger off this.
Reviewed by: gnn
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D28132
high-resolution nanosecond timestamp used for the DTrace 'timestamp'
built-in variable. The new implementation uses the EL0 cycle
counter and frequency registers in ARMv8-A. This replaces a
previous implementation that relied on an instrumentation-safe
implementation of getnanotime(), which provided only timer
resolution.
MFC after: 3 days
Reviewed by: andrew, bsdimp (older version)
Useful comments appreciated: jrtc27, emaste
The existing implementation relies on each trap handler saving a normal
stack frame record, which is a waste of time and space when we're
already saving a trapframe to the stack. It's also wrong as it currently
saves LR not ELR.
Instead of patching it up, rewrite it based on the RISC-V implementation
with inspiration from the amd64 implementation for how to handle
vectored traps to provide an improved implementation. This includes
compressing the information down to one line like other architectures
rather than the highly-verbose old form that repeats itself by printing
LR and FP in one frame only to print them as PC and SP in the next. It
also includes printing out actually useful information about the traps
that occurred, though FAR is not saved in the trapframe so we cannot
print it (in general it can be clobbered between when the trap happened
and now), only ESR.
The AAPCS also allows the stack frame record to be located anywhere in
the frame, not just the top, so the caller's SP is not at a fixed offset
from the callee's FP like on almost all other architectures in
existence. This means there is no way to derive the caller's SP in the
unwinder, and so we have to drop that bit of (unused) state everywhere.
Reviewed by: jhb, markj
Differential Revision: https://reviews.freebsd.org/D28026
A more complete fix for this function is being worked on in D28054. Fix
the uninitialized variable error so that builds can at least proceed.
Reported by: several
Some stack frames are too large for a store pair instruction we already
detect in the arm64 fbt code. Add support for handling subtracting the
stack pointer directly.
Sponsored by: Innovate UK
When searching for an instruction to patch out in the arm64 function
boundary trace we search for a store pair with a write back. This
instruction is commonly used to store two registers to the stack
and update the stack pointer to hold space for more.
This works in many cases, however not all functions use this, e.g.
when the stack frame is too large. In these cases we may find another
instruction of the same type that doesn't store through the stack
pointer. Filter these instructions out and assume if we see one we
are past the function prologue.
Reported by: rwatson
Sponsored by: Innovate UK
- Implement a dtrace_getnanouptime(), matching the existing
dtrace_getnanotime(), to avoid DTrace calling out to a potentially
instrumentable function.
(These should probably both be under KDTRACE_HOOKS. Also, it's not clear
to me that they are correct implementations for the DTrace thread time
functions they are used in .. fixes for another commit.)
- Don't allow FBT to instrument functions involved in EL1 exception handling
that are involved in FBT trap processing: handle_el1h_sync() and
do_el1h_sync().
- Don't allow FBT to instrument DDB and KDB functions, as that makes it
rather harder to debug FBT problems.
Prior to these changes, use of FBT on FreeBSD/arm64 rapidly led to kernel
panics due to recursion in DTrace.
Reliable FBT on FreeBSD/arm64 is reliant on another change from @andrew to
have the aarch64 instrumentor more carefully check that instructions it
replaces are against the stack pointer, which can otherwise lead to memory
corruption. That change remains under review.
MFC after: 2 weeks
Reviewed by: andrew, kp, markj (earlier version), jrtc27 (earlier version)
Differential revision: https://reviews.freebsd.org/D27766
This same check is used on other architectures. Previously this would
permit a stack frame to unwind into any arbitrary kernel address
(including unmapped addresses).
Reviewed by: andrew, markj
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27362
- Push the kstack_contains check down into unwind_frame() so that it
is honored by DDB and DTrace.
- Check that the trapframe for an exception frame is contained in the
traced thread's kernel stack for DDB traces.
Reviewed by: markj
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27357
The sdt module's load handler iterates over SDT linker sets for the
kernel and all loaded modules to create probes and providers defined by
SDT(9). Probes in one module may belong to a provider in a different
module, but when a probe is created we assume that the provider is
already defined. To maintain this invariant, modify the load handler to
perform two separate passes over loaded modules: one to define providers
and the other to define probes.
The problem manifests when loading linux.ko, which depends on
linux_common.ko, which defines providers used by probes defined in
linux.ko.
Reported by: gallatin
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
This catches up to the changes made to struct unwind_state in r364180.
Reviewed by: mhorne
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27360
This is useful for stack unwinders which need to avoid out-of-bounds
reads of a kernel stack which can trigger kernel faults.
Reviewed by: kib, markj
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27356
According to code comments the original motivation was to allow for
malloc_type_internal changes without ABI breakage. This can be trivially
accomplished by providing spare fields and versioning the struct, as
implemented in the patch below.
The upshots are one less memory indirection on each alloc and disappearance
of mt_zone.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D27104
Return values are passed in a0, so read it from there. We also pass a1 through
to userspace, as the ABI allows small structs to be returned in registers
a0/a1. While here read the register values directly from the trapframe rather
than rtval, and remove the now unneeded argument from dtrace_invop().
Set fbtp_roffset so that we get the correct return location in arg0.
Reviewed by: markj
Sponsored by: Axiado
Differential Revision: https://reviews.freebsd.org/D26389
