o Support for ptrace T_ATTACH/T_DETACH and T_SYSCALL
o PM signal handling logic should now work properly, even with debuggers
being present
o Asynchronous PM/VFS protocol, full IPC support for senda(), and
AMF_NOREPLY senda() flag
DETAILS
Process stop and delay call handling of PM:
o Added sys_runctl() kernel call with sys_stop() and sys_resume()
aliases, for PM to stop and resume a process
o Added exception for sending/syscall-traced processes to sys_runctl(),
and matching SIGKREADY pseudo-signal to PM
o Fixed PM signal logic to deal with requests from a process after
stopping it (so-called "delay calls"), using the SIGKREADY facility
o Fixed various PM panics due to race conditions with delay calls versus
VFS calls
o Removed special PRIO_STOP priority value
o Added SYS_LOCK RTS kernel flag, to stop an individual process from
running while modifying its process structure
Signal and debugger handling in PM:
o Fixed debugger signals being dropped if a second signal arrives when
the debugger has not retrieved the first one
o Fixed debugger signals being sent to the debugger more than once
o Fixed debugger signals unpausing process in VFS; removed PM_UNPAUSE_TR
protocol message
o Detached debugger signals from general signal logic and from being
blocked on VFS calls, meaning that even VFS can now be traced
o Fixed debugger being unable to receive more than one pending signal in
one process stop
o Fixed signal delivery being delayed needlessly when multiple signals
are pending
o Fixed wait test for tracer, which was returning for children that were
not waited for
o Removed second parallel pending call from PM to VFS for any process
o Fixed process becoming runnable between exec() and debugger trap
o Added support for notifying the debugger before the parent when a
debugged child exits
o Fixed debugger death causing child to remain stopped forever
o Fixed consistently incorrect use of _NSIG
Extensions to ptrace():
o Added T_ATTACH and T_DETACH ptrace request, to attach and detach a
debugger to and from a process
o Added T_SYSCALL ptrace request, to trace system calls
o Added T_SETOPT ptrace request, to set trace options
o Added TO_TRACEFORK trace option, to attach automatically to children
of a traced process
o Added TO_ALTEXEC trace option, to send SIGSTOP instead of SIGTRAP upon
a successful exec() of the tracee
o Extended T_GETUSER ptrace support to allow retrieving a process's priv
structure
o Removed T_STOP ptrace request again, as it does not help implementing
debuggers properly
o Added MINIX3-specific ptrace test (test42)
o Added proper manual page for ptrace(2)
Asynchronous PM/VFS interface:
o Fixed asynchronous messages not being checked when receive() is called
with an endpoint other than ANY
o Added AMF_NOREPLY senda() flag, preventing such messages from
satisfying the receive part of a sendrec()
o Added asynsend3() that takes optional flags; asynsend() is now a
#define passing in 0 as third parameter
o Made PM/VFS protocol asynchronous; reintroduced tell_fs()
o Made PM_BASE request/reply number range unique
o Hacked in a horrible temporary workaround into RS to deal with newly
revealed RS-PM-VFS race condition triangle until VFS is asynchronous
System signal handling:
o Fixed shutdown logic of device drivers; removed old SIGKSTOP signal
o Removed is-superuser check from PM's do_procstat() (aka getsigset())
o Added sigset macros to allow system processes to deal with the full
signal set, rather than just the POSIX subset
Miscellaneous PM fixes:
o Split do_getset into do_get and do_set, merging common code and making
structure clearer
o Fixed setpriority() being able to put to sleep processes using an
invalid parameter, or revive zombie processes
o Made find_proc() global; removed obsolete proc_from_pid()
o Cleanup here and there
Also included:
o Fixed false-positive boot order kernel warning
o Removed last traces of old NOTIFY_FROM code
THINGS OF POSSIBLE INTEREST
o It should now be possible to run PM at any priority, even lower than
user processes
o No assumptions are made about communication speed between PM and VFS,
although communication must be FIFO
o A debugger will now receive incoming debuggee signals at kill time
only; the process may not yet be fully stopped
o A first step has been made towards making the SYSTEM task preemptible
and DEV_IOCTL_S as replacements for DEV_READ, DEV_WRITE, DEV_SCATTER,
DEV_GATHER and DEV_IOCTL. Instead of a direct address, the *_S commands
pass 'grant ids' to the drivers which are referenced through a new set
of copy calls (sys_safecopyfrom and sys_safecopyto). in order for this
copy to succeed, the grant must have previously been created in the
address space of the granter.
. bitmap manipulation functions moved to <minix/bitmap.h>
. HIGHPOS introduced as field containing high 32 bits of position in
device I/O message; TTY_FLAGS no longer used
. IO_GRANT field introduced for GRANTs, to replace ADDRESS
. REP_IO_GRANT field for un-SUSPEND messages introduced to indicate
grant for which I/O was done to disambiguate messages
. SYS_SAFECOPYFROM and SYS_SAFECOPYTO introduced as new calls
. SYS_PRIV_SET_GRANTS code introduced as a code to set the address and
size of the grant table in a process' own address space
. 'type' and 'direction' field of _ins* and _outs* I/O functions
are merged into one by ORing _DIO_INPUT/_DIO_OUTPUT and _DIO_BYTE/_DIO_WORD
etc. This allows for an additional parameter, _DIO_SAFE, which indicates
the address in another address space isn't actually an address, but
a grant id. Also needs an offset, for which fields had to be merged.
. SCP_* are field names for SYS_SAFECOPY* functions
. DIAGNOSTICS and GET_KMESS moved to their own range above DIAG_BASE,
added DIAGNOSTICS_S which is a grant-based variant of DIAGNOSTICS
. removed obsolete BINCOMPAT and SRCCOMPAT options
. added GRANT_SEG type for use in vircopy - allows copying to a grant
id (without offset)
. added _MINIX_IOCTL_* macros that decode information encoded by
_IO* macros in ioctl codes, used to check which grants are necessary
for an ioctl
. introduced the type endpoint_t for process endpoints, changed some
prototypes and struct field types to match
. renamed protected to prot for g++
need /tmp any more since 16MB root device; increase to 3.0.5 to make new
CD with working FXP driver. (not tagged 3.0.5 yet as at driver bios-copy
workaround hasn't been done.)
