match_opcode() is defined in FBT, kinst, and dtrace_subr.c. The function
prologue-checking functions are defined in FBT and kinst.
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40335
dtrace_instr_size() is needed by the forthcoming RISC-V port of kinst,
as well as by libdtrace in D38825 for both amd64 and RISC-V.
Reviewed by: markj, mhorne
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39489
This will be used by a forthcoming port of the kinst provider.
Reviewed by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39481
Pretty trivial following other implementations. The existing
dtrace_getustack_common() does most of the work.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38303
The unwind logic was copied from AArch64 which follows the peculiar
AACPS (where, unlike typical RISC architectures, its frame pointer
follows an x86/stack machine-like convention where the frame pointer
points at the bottom of the frame record, not the top). Delete the
pointless riscv_frame struct and fix this.
Reviewed by: mhorne
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D28054
We must detect the correct amount to increment sepc, as it may have been
a compressed instruction that triggered the fault.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38299
In order to read or write userspace memory without generating an access
fault, we must first enable the SUM bit in the sstatus CSR.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38298
Backtraces for fbt probes are missing the caller's frame. Despite what
the inherited comment claims, we do need to insert this manually on
riscv. In fbt_invop(), set cpu_dtrace_caller to be the return address,
not addr.
We should not increment aframes within this function, since we begin the
main loop by unwinding past the current frame.
Plus some very small comment/style tweaks.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D37661
This allows invop-based providers (i.e., fbt and kinst) to expose the
register file of the CPU at the point where the probe fired. It does
not work for SDT providers because their probes are implemented as plain
function calls and so don't save registers. It's not clear what
semantics "regs" should have for them anyway.
This is akin to "uregs", which nominally provides access to the
userspace registers. In fact, DIF already had a DIF_VAR_REGS variable
defined, it was simply unimplemented.
Usage example: print the contents of %rdi upon each call to
amd64_syscall():
fbt::amd64_syscall:entry {printf("%x", regs[R_RDI]);}
Note that the R_* constants are defined in /usr/lib/dtrace/regs_x86.d.
Currently there are no similar definitions for non-x86 platforms.
Reviewed by: christos
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D36799
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
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
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
- 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
- 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
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
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
assym is only to be included by other .s files, and should never
actually be assembled by itself.
Reviewed by: imp, bdrewery (earlier)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D14180
The MFC will include a compat definition of smp_no_rendevous_barrier()
that calls smp_no_rendezvous_barrier().
Reviewed by: gnn, kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D10313
