* For sparc64 and amd64, define *SIZ32 VM constants.
* Add a new function pointer to struct emul, pointing at a function
that will return the default VM map address. The default function
is uvm_map_defaultaddr, which just uses the VM_DEFAULT_ADDRESS
macro. This gives emulations control over the default map address,
and allows things to be mapped at the right address (in 32bit range)
for COMPAT_NETBSD32.
* Add code to adjust the data and stack limits when a COMPAT_NETBSD32
or COMPAT_SVR4_32 binary is executed.
* Don't use USRSTACK in kern_resource.c, use p_vmspace->vm_minsaddr
instead (emulations might have set it differently)
* Since this changes struct emul, bump kernel version to 3.99.2
Tested on amd64, compile-tested on sparc64.
This areas is called the comm pages. It is used to provide fast access to
several data and functions.
The comm pages are mapped starting at 0xffff800 (address chosed so that
absolute branch can be used, so it can be accessed even when dynamic linking
is not ready). NetBSD has the user stack here, so we need to provide a
Darwin-specific stack setup routine which sets the top of the stack at
0xbfff0000.
This implementation is not complete but it does enough to get MacOS X.3
starting again (static binaries run, dynamic binaries still have an issue).
in the comm pages functions, we only implement bcopy, pthread_self and
memcpy.
TODO:
- clean up the powerpc specific code from MD parts
- for now we map only one page to avoid a crash, we want two pages.
- write all the comm functions.
fit what it does.
The softsignal feature is used in Darwin to trace processes. When the
traced process gets a signal, this raises an exception. The debugger will
receive the exception message, use ptrace with PT_THUPDATE to pass the
signal to the child or discard it, and then it will send a reply to the
exception message, to resume the child.
With the hook at the beginnng of kpsignal2, we are in the context of the
signal sender, which can be the kill(1) command, for instance. We cannot
afford to sleep until the debugger tells us if the signal should be
delivered or not.
Therefore, the hook to generate the Mach exception must be in the traced
process context. That was we can sleep awaiting for the debugger opinion
about the signal, this is not a problem. The hook is hence located into
issignal, at the place where normally SIGCHILD is sent to the debugger,
whereas the traced process is stopped. If the hook returns 0, we bypass
thoses operations, the Mach exception mecanism will take care of notifying
the debugger (through a Mach exception), and stop the faulting thread.
exec case, as the emulation already has the ability to intercept that
with the e_proc_exec hook. It is the responsability of the emulation to
take appropriaye action about lwp_emuldata in e_proc_exec.
Patch reviewed by Christos.
so that a specific emulation has the oportunity to filter out some signals.
if sigfilter returns 0, then no signal is sent by kpsignal2().
There is another place where signals can be generated: trapsignal. Since this
function is already an emulation hook, no call to the sigfilter hook was
introduced in trapsignal.
This is needed to emulate the softsignal feature in COMPAT_DARWIN (signals
sent as Mach exception messages)
blocked in the kernel. The task that catched the exception may unblock
it by sending a reply to the exception message (Of course it will have
to change something so that the exception is not immediatly raised again).
Handling of this reply is a bit complicated, as the kernel acts as the
client instead of the server. In this situation, we receive a message
but we will not send any reply (the message we receive is already a reply).
I have not found anything better than a special case in
mach_msg_overwrite_trap() to handle this.
A surprise: exceptions ports are preserved accross forks.
While we are there, use appropriate 64 bit types for make_memory_entry_64.
may turn into exceptions on Mach: a small message sent by the kernel to
the task that requested the exception.
On Darwin, when an exception is sent, no signal can be delivered.
TODO: more exceptions: arithmetic, bad instructions, emulation, s
software, and syscalls (plain and Mach). There is also RPC alert, but
I have no idea about what it is.
While we are there, remove some user ktrace in notification code, and add
a NODEF qualifier in mach_services.master: it will be used for notifications
and exceptions, where the kernel is always client and never server: we
don't want the message to be displayed as "unimplemented xxx" in kdump (thus
UNIMPL is not good), but we don't want to generate the server prototype
(therefore, STD is not good either). NODEF will declare it normally in the
name tables without creating the prototype.
static binary: otool). Dynamic binaires have a pointer to the Mach-O
header on the top of the stack, static binaries don't have this, and
having it produced a crash.
One bugfix: the EXEC_MACHO code assumes that entry = NULL means that
the entry point has not been found in the load commands seen so far.
Therefore we need to initialized entry to NULL if we want a static binary
to discover it. (dynamic binaries were forced to iscover it because when
the intepreter load command is found, entry is updated whatever its
value was before).
One hack: Both COMPAT_MACH and COMPAT_DARWIN are willing to run Mach-O
binaries. COMPAT_MACH fails for dynamic binaries because it cannot find
the interpreter in /emul/mach. For static binaires, it will accept them
(and for Darwin static binaries, this will cause a failure). Until we
rite a test for matchinf Darwin static binaries, just swap the order of
COMPAT_MACH and COMPAT_DARWIN in the exec switch so that COMPAT_DARWIN
is tried first (this will have the advantage of speeding up program
startup). EXECSW_PRIO_{FIRST_LAST} does not seem to work...
and make the stack and heap non-executable by default. the changes
fall into two basic catagories:
- pmap and trap-handler changes. these are all MD:
= alpha: we already track per-page execute permission with the (software)
PG_EXEC bit, so just have the trap handler pay attention to it.
= i386: use a new GDT segment for %cs for processes that have no
executable mappings above a certain threshold (currently the
bottom of the stack). track per-page execute permission with
the last unused PTE bit.
= powerpc/ibm4xx: just use the hardware exec bit.
= powerpc/oea: we already track per-page exec bits, but the hardware only
implements non-exec mappings at the segment level. so track the
number of executable mappings in each segment and turn on the no-exec
segment bit iff the count is 0. adjust the trap handler to deal.
= sparc (sun4m): fix our use of the hardware protection bits.
fix the trap handler to recognize text faults.
= sparc64: split the existing unified TSB into data and instruction TSBs,
and only load TTEs into the appropriate TSB(s) for the permissions.
fix the trap handler to check for execute permission.
= not yet implemented: amd64, hppa, sh5
- changes in all the emulations that put a signal trampoline on the stack.
instead, we now put the trampoline into a uvm_aobj and map that into
the process separately.
originally from openbsd, adapted for netbsd by me.
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.
Bump the kernel rev up to 1.6V
send, send once, and dead names, not for port sets and receive rights.
This make vi and telnet able to work again.
Also removed the all process right list and its lock, which got useless. The
all process lock is replaced by a per process lock, located in struct
mach_emuldata.
Also one bug fix: we did not correctly called Mach hooks for struct emuldata
initialization and release for Darwin processes.
for forking the traditional UNIX init(8) and it does the Mach port naming
service. We need mach_init for the naming service, but unfortunately, it
will only act as such if its PID is 1. We introduce a sysctl
(emul.darwin.init_pid) to fool a given process into thinking its PID is 1.
That way we can get mach_init into behaving as the name server.
Typical use:
/sbin/sysctl -w emul.darwin.init_pid=$$ ; exec /emul/darwin/sbin/mach_init
used to get and set the thread user value, which is an opaque pointer to
a per thread structure stored in userland. cthread_self() is used by Darwin
as an implementation for pthread_self(), which return the thread id.
We use the p_emuldata field of struct proc in order to keep track of the
thread user value. For now the value is per-process, but we will make it
per-thread when we will take care of threading.
While we are there, do some KNF
macho_hdr, argc, *argv, NULL, *envp, NULL, progname, NULL,
*progname, **argv, **envp
Where progname is a pointer to the program name as given in the first
argument to execve(), and macho_hdr a pointer to the Mach-O header at
the beginning of the executable file.
christos