Commit Graph

183 Commits

Author SHA1 Message Date
Jeff Roberson
6617724c5f Remove kernel support for M:N threading.
While the KSE project was quite successful in bringing threading to
FreeBSD, the M:N approach taken by the kse library was never developed
to its full potential.  Backwards compatibility will be provided via
libmap.conf for dynamically linked binaries and static binaries will
be broken.
2008-03-12 10:12:01 +00:00
Attilio Rao
22db15c06f VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
2008-01-13 14:44:15 +00:00
Attilio Rao
cb05b60a89 vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by:	Diego Sardina <siarodx at gmail dot com>,
		Andrea Di Pasquale <whyx dot it at gmail dot com>
2008-01-10 01:10:58 +00:00
Peter Wemm
4113f8d741 Fall back to the binary-specified interpreter (ld-elf.so.1) if the
ABI override binary isn't found.  This could probably be smoother, but
it is what I did in p4 change #126891 on 2007/09/27.  It should solve
the "ld-elf32.so.1"-in-chroot problem.
2008-01-05 08:35:56 +00:00
Konstantin Belousov
f231de478e Implement fetching of the __FreeBSD_version from the ELF ABI-tag note.
The value is read into the p_osrel member of the struct proc. p_osrel
is set to 0 for the binaries without the note.

MFC after:	3 days
2007-12-04 12:28:07 +00:00
Konstantin Belousov
93d1c72883 Check for the program headers alignment of the ELF images before
dereferencing. Unaligned access could cause panic on strict alignment
architectures.

Reviewed by:	marcel, marius (also tested on sparc64, thanks !)
MFC after:	3 days
2007-12-04 12:21:27 +00:00
Julian Elischer
e01eafef2a A bunch more files that should probably print out a thread name
instead of a process name.
2007-11-14 06:51:33 +00:00
Konstantin Belousov
89b57fcf01 Fix for the panic("vm_thread_new: kstack allocation failed") and
silent NULL pointer dereference in the i386 and sparc64 pmap_pinit()
when the kmem_alloc_nofault() failed to allocate address space. Both
functions now return error instead of panicing or dereferencing NULL.

As consequence, vmspace_exec() and vmspace_unshare() returns the errno
int. struct vmspace arg was added to vm_forkproc() to avoid dealing
with failed allocation when most of the fork1() job is already done.

The kernel stack for the thread is now set up in the thread_alloc(),
that itself may return NULL. Also, allocation of the first process
thread is performed in the fork1() to properly deal with stack
allocation failure. proc_linkup() is separated into proc_linkup()
called from fork1(), and proc_linkup0(), that is used to set up the
kernel process (was known as swapper).

In collaboration with:	Peter Holm
Reviewed by:	jhb
2007-11-05 11:36:16 +00:00
John Baldwin
19059a13ed Rework the support for ABIs to override resource limits (used by 32-bit
processes under 64-bit kernels).  Previously, each 32-bit process overwrote
its resource limits at exec() time.  The problem with this approach is that
the new limits affect all child processes of the 32-bit process, including
if the child process forks and execs a 64-bit process.  To fix this, don't
ovewrite the resource limits during exec().  Instead, sv_fixlimits() is
now replaced with a different function sv_fixlimit() which asks the ABI to
sanitize a single resource limit.  We then use this when querying and
setting resource limits.  Thus, if a 32-bit process sets a limit, then
that new limit will be inherited by future children.  However, if the
32-bit process doesn't change a limit, then a future 64-bit child will
see the "full" 64-bit limit rather than the 32-bit limit.

MFC is tentative since it will break the ABI of old linux.ko modules (no
other modules are affected).

MFC after:	1 week
2007-05-14 22:40:04 +00:00
Xin LI
4f506694bb Use FOREACH_PROC_IN_SYSTEM instead of using its unrolled form. 2007-01-17 14:58:53 +00:00
Alan Cox
976a87a284 Add vm map and object locking to each_writable_segment().
Noticed by: jhb@
MFC after: 3 weeks
2006-11-19 23:38:59 +00:00
Alan Cox
e5e6093ba9 Avoid a vm object reference leak in a rarely used code path.
An executable contains at most one PT_INTERP program header.  Therefore,
the loop that searches for it can terminate after it is found rather than
iterating over the entire set of program headers.

Eliminate an unneeded initialization.

Reviewed by: tegge
2006-01-21 20:11:49 +00:00
Maxim Sobolev
d49b21093c Fix breakage introduced in the previous commit. 2005-12-26 22:32:52 +00:00
Maxim Sobolev
900b28f9f6 Remove kern.elf32.can_exec_dyn sysctl. Instead extend Brandinfo structure
with flags bitfield and set BI_CAN_EXEC_DYN flag for all brands that usually
allow executing elf dynamic binaries (aka shared libraries). When it is
requested to execute ET_DYN elf image check if this flag is on after we
know the elf brand allowing execution if so.

PR:		kern/87615
Submitted by:	Marcin Koziej <creep@desk.pl>
2005-12-26 21:23:57 +00:00
Alan Cox
60bb39431a Maintain the lock on the vnode for most of exec_elfN_imgact().
Specifically, it is required for the I/O that may be performed by
elfN_load_section().

Avoid an obscure deadlock in the a.out, elf, and gzip image
activators.  Add a comment describing why the deadlock does not occur
in the common case and how it might occur in less usual circumstances.

Eliminate an unused variable from exec_aout_imgact().

In collaboration with: tegge
2005-12-24 04:57:50 +00:00
Alan Cox
373d1a3f8c Maintain the vnode lock throughout elfN_load_file() rather than releasing
it and reacquiring it in vrele().  Consequently, there is no reason to
increase the reference count on the vm object caching the file's pages.
Reviewed by: tegge

Eliminate unused parameters to elfN_load_file().
2005-12-21 18:58:40 +00:00
Alan Cox
ff6f03c7cd Eliminate an unneeded (vm_prot_t) parameter from two functions. Eliminate
unnecessary uses of a local variable.

Reviewed by: tegge
2005-12-20 23:42:18 +00:00
Alan Cox
044bbbb523 Correct a long-standing problem in elfN_map_insert(): In order to copy a
page to user space, the user space mapping must allow write access.

In collaboration with: tegge@
MFC after: 3 weeks
2005-12-17 19:40:47 +00:00
Alan Cox
584716b08a Style: The second argument to vm_map_find() should be NULL instead of 0. 2005-12-16 19:14:25 +00:00
Alan Cox
da61b9a69e Use sf_buf_alloc() instead of vm_map_find() on exec_map to create the
ephemeral mappings that are used as the source for three copy
operations from kernel space to user space.  There are two reasons for
making this change: (1) Under heavy load exec_map can fill up causing
vm_map_find() to fail.  When it fails, the nascent process is aborted
(SIGABRT).  Whereas, this reimplementation using sf_buf_alloc()
sleeps.  (2) Although it is possible to sleep on vm_map_find()'s
failure until address space becomes available (see kmem_alloc_wait()),
using sf_buf_alloc() is faster.  Furthermore, the reimplementation
uses a CPU private mapping, avoiding a TLB shootdown on
multiprocessors.

Problem uncovered by: kris@
Reviewed by: tegge@
MFC after: 3 weeks
2005-12-16 18:34:14 +00:00
Olivier Houchard
481a1fe19e Add a new sysctl, kern.elf[32|64].can_exec_dyn. When set to 1, one can
execute a ET_DYN binary (shared object).
This does not make much sense, but some linux scripts expect to be able to
execute /lib/ld-linux.so.2 (ldd comes to mind).
The sysctl defaults to 0.

MFC after:	3 days
2005-11-14 22:24:00 +00:00
Robert Watson
5f419982c2 Back out alpha/alpha/trap.c:1.124, osf1_ioctl.c:1.14, osf1_misc.c:1.57,
osf1_signal.c:1.41, amd64/amd64/trap.c:1.291, linux_socket.c:1.60,
svr4_fcntl.c:1.36, svr4_ioctl.c:1.23, svr4_ipc.c:1.18, svr4_misc.c:1.81,
svr4_signal.c:1.34, svr4_stat.c:1.21, svr4_stream.c:1.55,
svr4_termios.c:1.13, svr4_ttold.c:1.15, svr4_util.h:1.10,
ext2_alloc.c:1.43, i386/i386/trap.c:1.279, vm86.c:1.58,
unaligned.c:1.12, imgact_elf.c:1.164, ffs_alloc.c:1.133:

Now that Giant is acquired in uprintf() and tprintf(), the caller no
longer leads to acquire Giant unless it also holds another mutex that
would generate a lock order reversal when calling into these functions.
Specifically not backed out is the acquisition of Giant in nfs_socket.c
and rpcclnt.c, where local mutexes are held and would otherwise violate
the lock order with Giant.

This aligns this code more with the eventual locking of ttys.

Suggested by:	bde
2005-09-28 07:03:03 +00:00
Robert Watson
84d2b7df26 Add GIANT_REQUIRED and WITNESS sleep warnings to uprintf() and tprintf(),
as they both interact with the tty code (!MPSAFE) and may sleep if the
tty buffer is full (per comment).

Modify all consumers of uprintf() and tprintf() to hold Giant around
calls into these functions.  In most cases, this means adding an
acquisition of Giant immediately around the function.  In some cases
(nfs_timer()), it means acquiring Giant higher up in the callout.

With these changes, UFS no longer panics on SMP when either blocks are
exhausted or inodes are exhausted under load due to races in the tty
code when running without Giant.

NB: Some reduction in calls to uprintf() in the svr4 code is probably
desirable.

NB: In the case of nfs_timer(), calling uprintf() while holding a mutex,
or even in a callout at all, is a bad idea, and will generate warnings
and potential upset.  This needs to be fixed, but was a problem before
this change.

NB: uprintf()/tprintf() sleeping is generally a bad ideas, as is having
non-MPSAFE tty code.

MFC after:	1 week
2005-09-19 16:51:43 +00:00
Christian S.J. Peron
68ff2a4397 Improve the MP safeness associated with the creation of symbolic
links and the execution of ELF binaries. Two problems were found:

1) The link path wasn't tagged as being MP safe and thus was not properly
   protected.
2) The ELF interpreter vnode wasnt being locked in namei(9) and thus was
   insufficiently protected.

This commit makes the following changes:

-Sets the MPSAFE flag in NDINIT for symbolic link paths
-Sets the MPSAFE flag in NDINIT and introduce a vfslocked variable which
 will be used to instruct VFS_UNLOCK_GIANT to unlock Giant if it has been
 picked up.
-Drop in an assertion into vfs_lookup which ensures that if the MPSAFE
 flag is NOT set, that we have picked up giant. If not panic (if WITNESS
 compiled into the kernel). This should help us find conditions where vnode
 operations are in-sufficiently protected.

This is a RELENG_6 candidate.

Discussed with:	jeff
MFC after:	4 days
2005-09-15 15:03:48 +00:00
Peter Wemm
62919d788b Jumbo-commit to enhance 32 bit application support on 64 bit kernels.
This is good enough to be able to run a RELENG_4 gdb binary against
a RELENG_4 application, along with various other tools (eg: 4.x gcore).
We use this at work.

ia32_reg.[ch]: handle the 32 bit register file format, used by ptrace,
	procfs and core dumps.
procfs_*regs.c: vary the format of proc/XXX/*regs depending on the client
	and target application.
procfs_map.c: Don't print a 64 bit value to 32 bit consumers, or their
	sscanf fails.  They expect an unsigned long.
imgact_elf.c: produce a valid 32 bit coredump for 32 bit apps.
sys_process.c: handle 32 bit consumers debugging 32 bit targets.  Note
	that 64 bit consumers can still debug 32 bit targets.

IA64 has got stubs for ia32_reg.c.

Known limitations: a 5.x/6.x gdb uses get/setcontext(), which isn't
implemented in the 32/64 wrapper yet.  We also make a tiny patch to
gdb pacify it over conflicting formats of ld-elf.so.1.

Approved by:	re
2005-06-30 07:49:22 +00:00
Olivier Houchard
77f30ffff8 Don't set the default of kern.fallback_elf_brand to FreeBSD for arm, as
binutils now do the job for us
2005-05-24 22:21:44 +00:00
Jeff Roberson
e11a45c9e5 - Neither of our image formats require Giant now that the vm and vfs have
been locked.
2005-05-03 10:51:38 +00:00
Alan Cox
9f65fb13aa Remove GIANT_REQUIRED from elfN_load_section(). 2005-04-03 07:57:47 +00:00
Maxim Sobolev
610ecfe035 o Split out kernel part of execve(2) syscall into two parts: one that
copies arguments into the kernel space and one that operates
  completely in the kernel space;

o use kernel-only version of execve(2) to kill another stackgap in
  linuxlator/i386.

Obtained from:  DragonFlyBSD (partially)
MFC after:      2 weeks
2005-01-29 23:12:00 +00:00
Poul-Henning Kamp
8516dd18e1 Don't use VOP_GETVOBJECT, use vp->v_object directly. 2005-01-25 00:40:01 +00:00
Olivier Houchard
e0370a187c On arm, set the default elf brand to FreeBSD, until the binutils do it for us. 2004-09-23 23:29:24 +00:00
Marcel Moolenaar
4da47b2fec Add __elfN(dump_thread). This function is called from __elfN(coredump)
to allow dumping per-thread machine specific notes. On ia64 we use this
function to flush the dirty registers onto the backingstore before we
write out the PRSTATUS notes.

Tested on: alpha, amd64, i386, ia64 & sparc64
Not tested on: arm, powerpc
2004-08-11 02:35:06 +00:00
Doug Rabson
cfaf7e60cc Make sure that AT_PHDR has a useful value even for static programs. 2004-08-08 09:48:10 +00:00
Marcel Moolenaar
1f7a1baa37 After maintaining previous behaviour in writing out the core notes, it's
time now to break with the past: do not write the PID in the first note.
Rationale:
1.  [impact of the breakage] Process IDs in core files serve no immediate
    purpose to the debugger itself. They are only useful to relate a core
    file to a process. This can provide context to the person looking at
    the core file, provided one keeps track of this. Overall, not having
    the PID in the core file is only in very rare occasions unfortunate.
2.  [reason of the breakage] Having one PRSTATUS note contain the PID,
    while all others contain the LWPID of the corresponding kernel thread
    creates an irregularity for the debugger that cannot easily be worked
    around. This is caused by libthread_db correlating user thread IDs to
    kernel thread (aka LWP) IDs and thus aware of the actual LWPIDs.

Update comments accordingly.
2004-07-18 20:28:07 +00:00
Marcel Moolenaar
247aba2474 Allocate TIDs in thread_init() and deallocate them in thread_fini().
The overhead of unconditionally allocating TIDs (and likewise,
unconditionally deallocating them), is amortized across multiple
thread creations by the way UMA makes it possible to have type-stable
storage.
Previously the cost was kept down by having threads created as part
of a fork operation use the process' PID as the TID. While this had
some nice properties, it also introduced complexity in the way TIDs
were allocated. Most importantly, by using the type-stable storage
that UMA gives us this was also unnecessary.

This change affects how core dumps are created and in particular how
the PRSTATUS notes are dumped. Since we don't have a thread with a
TID equalling the PID, we now need a different way to preserve the
old and previous behavior. We do this by having the given thread (i.e.
the thread passed to the core dump code in td) dump it's state first
and fill in pr_pid with the actual PID. All other threads will have
pr_pid contain their TIDs. The upshot of all this is that the debugger
will now likely select the right LWP (=TID) as the initial thread.

Credits to: julian@ for spotting how we can utilize UMA.
Thanks to: all who provided julian@ with test results.
2004-06-26 18:58:22 +00:00
Tim J. Robbins
f99619a0dc Change the types of vn_rdwr_inchunks()'s len and aresid arguments to
size_t and size_t *, respectively. Update callers for the new interface.
This is a better fix for overflows that occurred when dumping segments
larger than 2GB to core files.
2004-06-05 02:18:28 +00:00
Tim J. Robbins
2b471bc616 Back out workaround for vn_rdwr_inchunks()'s INT_MAX length limitation
after discussions with bde; vn_rdwr_inchunks() itself should be fixed.
2004-06-05 02:00:12 +00:00
Tim J. Robbins
16e6d16299 Write segments to core dump files in maximally-sized chunks that neither
exceed vn_rdwr_inchunks()'s INT_MAX length limitation nor span a block
boundary. This fixes dumping segments larger than 2GB.

PR:	67546
2004-06-04 06:30:16 +00:00
Alan Cox
59c8bc40ce Utilize sf_buf_alloc() rather than pmap_qenter() (and sometimes
kmem_alloc_wait()) for mapping the image header.  On all machines with a
direct virtual-to-physical mapping and SMP/HTT i386s, this is a clear win.
2004-04-23 03:01:40 +00:00
Marcel Moolenaar
ece267ba58 Do not assume that the initial thread (i.e. the thread with the ID
equal to the process ID) is still present when we dump a core. It
already may have been destroyed. In that case we would end up
dereferencing a NULL pointer, so specifically test for that as well.

Reported & tested by: Dan Nelson <dnelson@allantgroup.com>
2004-04-08 06:37:00 +00:00
Marcel Moolenaar
8c9b7b2c84 Create NT_PRSTATUS and NT_FPREGSET notes for each and every thread
in the process. This is required for proper debugging of corefiles
created by 1:1 or M:N threaded processes. Add an XXX comment where
we should actually call a function that dumps MD specific notes.
An example of a MD specific note is the NT_PRXFPREG note for SSE
registers.

Since BFD creates non-annotated pseudo-sections for the first PRSTATUS
and FPREGSET notes (non-annotated in the sense that the name of the
section does not contain the pid/tid), make sure those sections describe
the initial thread of the process (i.e. the thread which tid equals the
pid). This is not strictly necessary, but makes sure that tools that use
the non-annotated section names will not change behaviour due to this
change.

The practical upshot of this all is that one can see the threads in
the debugger when looking at a corefile. For 1:1 threading this means
that *all* threads are visible.
2004-04-03 20:25:41 +00:00
Jacques Vidrine
3dc19c4677 Verify more bits of the ELF header: the program header table
entry size and the ELF version.  Also, avoid a potential integer
overflow when determining whether the ELF header fits entirely
within the first page.

Reviewed by:	jdp

A panic when attempting to execute an ELF binary with a bogus program
header table entry size was

Reported by:	Christer Öberg <christer.oberg@texonet.com>
2004-03-18 16:33:05 +00:00
John Baldwin
91d5354a2c Locking for the per-process resource limits structure.
- struct plimit includes a mutex to protect a reference count.  The plimit
  structure is treated similarly to struct ucred in that is is always copy
  on write, so having a reference to a structure is sufficient to read from
  it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
  limits from a process to keep the limit structure from changing out from
  under you while reading from it.
- Various global limits that are ints are not protected by a lock since
  int writes are atomic on all the archs we support and thus a lock
  wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
  behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
  either an rlimit, or the current or max individual limit of the specified
  resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
  other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
  (it didn't used the stackgap when it should have) but uses lim_rlimit()
  and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
  but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits.  It
  also no longer uses the stackgap for accessing sysctl's for the
  ibcs2_sysconf() syscall but uses kernel_sysctl() instead.  As a result,
  ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.

Submitted by:	mtm (mostly, I only did a few cleanups and catchups)
Tested on:	i386
Compiled on:	alpha, amd64
2004-02-04 21:52:57 +00:00
Peter Wemm
9b68618df0 Add an additional field to the elf brandinfo structure to support
quicker exec-time replacement of the elf interpreter on an emulation
environment where an entire /compat/* tree isn't really warranted.
2003-12-23 02:42:39 +00:00
Peter Wemm
c460ac3a00 Add sysentvec->sv_fixlimits() hook so that we can catch cases on 64 bit
systems where the data/stack/etc limits are too big for a 32 bit process.

Move the 5 or so identical instances of ELF_RTLD_ADDR() into imgact_elf.c.

Supply an ia32_fixlimits function.  Export the clip/default values to
sysctl under the compat.ia32 heirarchy.

Have mmap(0, ...) respect the current p->p_limits[RLIMIT_DATA].rlim_max
value rather than the sysctl tweakable variable.  This allows mmap to
place mappings at sensible locations when limits have been reduced.

Have the imgact_elf.c ld-elf.so.1 placement algorithm use the same
method as mmap(0, ...) now does.

Note that we cannot remove all references to the sysctl tweakable
maxdsiz etc variables because /etc/login.conf specifies a datasize
of 'unlimited'.  And that causes exec etc to fail since it can no
longer find space to mmap things.
2003-09-25 01:10:26 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Marcel Moolenaar
a063facbf6 Fix ia32 compat on ia64. Recent ia64 MD changes caused the garbage on
the stack to be changed in a way incompatible with elf32_map_insert()
where we used data_buf without initializing it for when the partial
mapping resulting in a misaligned image (typical when the page size
implied by the image is not the same as the page size in use by the
kernel). Since data_buf is passed by reference to vm_map_find(), the
compiler cannot warn about it.

While here, move all local variables to the top of the function.
2003-05-31 19:55:05 +00:00
Warner Losh
a163d034fa Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
Alfred Perlstein
44956c9863 Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
Jake Burkholder
e548a1d4c8 - Provide backwards compatibility for kern.fallback_elf_brand.
- Use the generic elf type macros in imgact_elf.h instead of ifdefing the
  entire contents of the header.
2003-01-05 03:48:14 +00:00