PT_LWPINFO is a legacy ptrace(2) operation that was originally intended
to retrieve the thread (LWP) information inside a traced process.
It has a number of flaws and is confused with PT_LWPINFO from FreeBSD.
PT_LWPSTATUS and PT_LWPNEXT address the problems (shortly by: rename,
removal of pl_event) and introduces new features: signal context
(pl_sigpend, pl_sigmask), LWP name (pl_name), LWP TLS base address
(pl_private). The private pointer was so far missing information for
a debugger.
PT_LWPSTATUS@nnn is now shipped with core(5) files and contain LWP specific
information, so far missed in the core(5) files.
PT_LWPSTATUS retrieves LWP information for the prompted thread.
PT_LWPNEXT retrieves LWP information for the next thread, borrowing the
semantics from NetBSD specific PT_LWPINFO.
PT_LWPINFO is namespaced with __LEGACY_PT_LWPINFO and still available for
the foreseeable future, without plans of removing it.
Add ATF tests for PT_LWPSTATUS + PT_LWPNEXT.
Keep ATF tests for PT_LWPINFO.
Switch GDB to new API.
Proposed on tech-kern@.
Change the code to remove the LWP id assumptions that broke after
src/sys/kern/kern_lwp.c r. 1.206.
Original code by <mgorny>, tested and tweaked by myself.
- Add 'mach' and 'vcpu' backpointers in the nvmm_io and nvmm_mem
structures.
- Rename 'nvmm_callbacks' to 'nvmm_assist_callbacks'.
- Rename and migrate NVMM_MACH_CONF_CALLBACKS to NVMM_VCPU_CONF_CALLBACKS,
it now becomes per-VCPU.
issues in the libnvmm API.
- Rename NVMM_CAPABILITY_VERSION to NVMM_KERN_VERSION, and check it in
libnvmm. Introduce NVMM_USER_VERSION, for future use.
- In libnvmm, open "/dev/nvmm" as read-only and with O_CLOEXEC. This is to
avoid sharing the VMs with the children if the process forks. In the
NVMM driver, force O_CLOEXEC on open().
- Rename the following things for consistency:
nvmm_exit* -> nvmm_vcpu_exit*
nvmm_event* -> nvmm_vcpu_event*
NVMM_EXIT_* -> NVMM_VCPU_EXIT_*
NVMM_EVENT_INTERRUPT_HW -> NVMM_VCPU_EVENT_INTR
NVMM_EVENT_EXCEPTION -> NVMM_VCPU_EVENT_EXCP
Delete NVMM_EVENT_INTERRUPT_SW, unused already.
- Slightly reorganize the MI/MD definitions, for internal clarity.
- Split NVMM_VCPU_EXIT_MSR in two: NVMM_VCPU_EXIT_{RD,WR}MSR. Also provide
separate u.rdmsr and u.wrmsr fields. This is more consistent with the
other exit reasons.
- Change the types of several variables:
event.type enum -> u_int
event.vector uint64_t -> uint8_t
exit.u.*msr.msr: uint64_t -> uint32_t
exit.u.io.type: enum -> bool
exit.u.io.seg: int -> int8_t
cap.arch.mxcsr_mask: uint64_t -> uint32_t
cap.arch.conf_cpuid_maxops: uint64_t -> uint32_t
- Delete NVMM_VCPU_EXIT_MWAIT_COND, it is AMD-only and confusing, and we
already intercept 'monitor' so it is never armed.
- Introduce vmx_exit_insn() for NVMM-Intel, similar to svm_exit_insn().
The 'npc' field wasn't getting filled properly during certain VMEXITs.
- Introduce nvmm_vcpu_configure(). Similar to nvmm_machine_configure(),
but as its name indicates, the configuration is per-VCPU and not per-VM.
Migrate and rename NVMM_MACH_CONF_X86_CPUID to NVMM_VCPU_CONF_CPUID.
This becomes per-VCPU, which makes more sense than per-VM.
- Extend the NVMM_VCPU_CONF_CPUID conf to allow triggering VMEXITs on
specific leaves. Until now we could only mask the leaves. An uint32_t
is added in the structure:
uint32_t mask:1;
uint32_t exit:1;
uint32_t rsvd:30;
The two first bits select the desired behavior on the leaf. Specifying
zero on both resets the leaf to the default behavior. The new
NVMM_VCPU_EXIT_CPUID exit reason is added.
Fix a race condition that caused PT_GET_SIGINFO to return incorrect
information when multiple signals were delivered concurrently
to different LWPs. Add a regression test that verifies that when 50
threads concurrently use pthread_kill() on themselves, the debugger
receives all signals with correct information.
The kernel uses separate signal queues for each LWP. However,
the signal context used to implement PT_GET_SIGINFO is stored in 'struct
proc' and therefore common to all LWPs in the process. Previously,
this member was filled in kpsignal2(), i.e. when the signal was sent.
This meant that if another LWP managed to send another signal
concurrently, the data was overwritten before the process was stopped.
As a result, PT_GET_SIGINFO did not report the correct LWP and signal
(it could even report a different signal than wait()). This can be
quite reliably reproduced with the number of 20 LWPs, however it can
also occur with 10.
This patch moves setting of signal context to issignal(), just before
the process is actually stopped. The data is taken from per-LWP
or per-process signal queue. The added test confirms that the debugger
correctly receives all signals, and PT_GET_SIGINFO reports both correct
LWP and signal number.
Reviewed by kamil.
address size is 16 bits, regardless of the actual operating mode. With
this special map there can be two registers referenced at once, and
also disp16-only.
Implement this special behavior, and add associated tests. While here
simplify a few things.
With this in place, the Windows 95 installer initializes correctly.
Part of PR/54611.
GCC_NO_FORMAT_TRUNCATION -Wno-format-truncation (GCC 7/8)
GCC_NO_STRINGOP_TRUNCATION -Wno-stringop-truncation (GCC 8)
GCC_NO_STRINGOP_OVERFLOW -Wno-stringop-overflow (GCC 8)
GCC_NO_CAST_FUNCTION_TYPE -Wno-cast-function-type (GCC 8)
use these to turn off warnings for most GCC-8 complaints. many
of these are false positives, most of the real bugs are already
commited, or are yet to come.
we plan to introduce versions of (some?) of these that use the
"-Wno-error=" form, which still displays the warnings but does
not make it an error, and all of the above will be re-considered
as either being "fix me" (warning still displayed) or "warning
is wrong."
This is a torture, but on purpose to catch LWP_CREATED and LWP_EXITED bugs.
The threads do nothing other than calling sched_yield() in a loop.
MAXLWP is now defined to 2048 on all ports.
This change effects the following tests:
- trace_thread_nolwpevents
- trace_thread_lwpexit
- trace_thread_lwpcreate
- trace_thread_lwpcreate_and_exit
avoid passing the same pointer in multiple arguments for restrict
marked arguments:
- sigaction() wants separate in/out
- use memmove() not memcpy() for overlapping regions (this may fix
a real bug in nvi -- but it seems unlikely)
- select() wants separate read/write/except
- sigprocmask() wants separate set/oset
Assert that PT_GET_PROCESS_STATE for !child and !lwp events returns
non-error and zeroed struct ptrace_state.
These checks are not really special to traceme_raise, it's just an
opportunity to reuse them in an existing tests without writing a dedicated
one.
This behavior is needed to maintain in 3rd party software (GDB).
- Add cchar command to director test language to allow a complex character
to be defined and passed to the slave.
- Removed the distinction between args and returns internally to prevent
confusing the two which leads to errors and/or crashes.
- Converted mutt_test to use the new cchar definition and fixed the
check files for the test.
Define _REENTRANT for MKSANITIZER build. This is needed for at least stdio
code. This caused new build issued with duplicated symbols in few places
and rump kernel code picking different code paths borrowed from libc.
Handle all this in one go.
Add bsd.sanitizer.mk to share common code used by programs and libraries.
Switch from realall to beforeinstall target in .syms files. This is more
reliable in MKSANITIZER.
differences more exact, allowing between 0 and 1 s delay between the
expected wakeup and the actual event happening.
Also convert the QEMU special case code to the same scheme, but for now
disable it (with XXX mark) and see if the proper timing limits fix that
case too.
If not, we will re-enable the QEMU special case.
Add a first test for triggering a core dump in the debugged process
(via PT_DUMPCORE) and verifying it. The test finds procinfo note
and checks its contents.
The core dump is processed through libelf. However, it only provides
for finding all note segments (or sections?). I had to implement
finding and processing individual notes myself. I've added
a core_find_note() function that will be reused in future tests.
Reviewed by kamil.
Introduce two new ptrace() requests: PT_GETXSTATE and PT_SETXSTATE,
that provide access to the extended (and extensible) set of FPU
registers on amd64 and i386. At the moment, this covers AVX (YMM)
and AVX-512 (ZMM, opmask) registers. It can be easily extended
to cover further register types without breaking backwards
compatibility.
PT_GETXSTATE issues the XSAVE instruction with all kernel-supported
extended components enabled. The data is copied into 'struct xstate'
(which -- unlike the XSAVE area itself -- has stable format
and offsets).
PT_SETXSTATE issues the XRSTOR instruction to restore the register
values from user-provided 'struct xstate'. The function replaces only
the specific XSAVE components that are listed in 'xs_rfbm' field,
making it possible to issue partial updates.
Both syscalls take a 'struct iovec' pointer rather than a direct
argument. This requires the caller to explicitly specify the buffer
size. As a result, existing code will continue to work correctly
when the structure is extended (performing partial reads/updates).
mknod with mode & S_IFIFO and dev=0 shall behave like mkfifo.
Update the documentation to reflect this state.
Add ATF tests.
This is an in-kernel implementation as typically user-space programs use
mkfifo(2) directly, however whenever there is need to bypass libc (like in
valgrind) then portable POSIX software calls the mknod syscall.
Noted on tech-kern@ by Greg Troxel.
kamil