Commit Graph

91 Commits

Author SHA1 Message Date
Nathan Whitehorn
e69dff491d Use the ABI-mandated thread pointer register (r2 for ppc32, r13 for ppc64)
instead of a PCPU field for curthread. This averts a race on SMP systems
with a high interrupt rate where the thread looking up the value of
curthread could be preempted and migrated between obtaining the PCPU
pointer and reading the value of pc_curthread, resulting in curthread being
observed to be the current thread on the thread's original CPU. This played
merry havoc with the system, in particular with mutexes. Many thanks to
jhb for helping me work this one out.

Note that Book-E is in principle susceptible to the same problem, but has
not been modified yet due to lack of Book-E hardware.

MFC after:	2 weeks
2011-06-23 22:21:28 +00:00
Dmitry Chagin
a5c1afadeb Add macro to test the sv_flags of any process. Change some places to test
the flags instead of explicit comparing with address of known sysentvec
structures.

MFC after:	1 month
2011-01-26 20:03:58 +00:00
Nathan Whitehorn
ff30eecffe Fix handling of NX pages on capable CPUs. Thanks to kib for prodding me
in the right direction.
2011-01-13 04:37:48 +00:00
Nathan Whitehorn
87acfc2a51 Fix two mistakes on 32-bit systems. The slbmte code in syscall() is 64-bit
only, and should be protected with an ifdef, and the no-execute bit in
32-bit set_user_sr() should be set before the comparison, not after, or
it will never match.
2010-11-03 16:21:47 +00:00
Nathan Whitehorn
e0f88469c7 Clean up the user segment handling code a little more. Now that
set_user_sr() itself caches the user segment VSID, there is no need for
cpu_switch() to do it again. This change also unifies the 32 and 64-bit
code paths for kernel faults on user pages and remaps the user SLB slot
on 64-bit systems when taking a syscall to avoid some unnecessary segment
exception traps.
2010-11-03 15:15:48 +00:00
Nathan Whitehorn
54c562081f Restructure the way the copyin/copyout segment is stored to prevent a
concurrency bug. Since all SLB/SR entries were invalidated during an
exception, a decrementer exception could cause the user segment to be
invalidated during a copyin()/copyout() without a thread switch that
would cause it to be restored from the PCB, potentially causing the
operation to continue on invalid memory. This is now handled by explicit
restoration of segment 12 from the PCB on 32-bit systems and a check in
the Data Segment Exception handler on 64-bit.

While here, cause copyin()/copyout() to check whether the requested
user segment is already installed, saving some pipeline flushes, and
fix the synchronization primitives around the mtsr and slbmte
instructions to prevent accessing stale segments.

MFC after:	2 weeks
2010-10-30 23:07:30 +00:00
Nathan Whitehorn
2639d62ec2 Handle vector assist traps without a kernel panic, by setting denormalized
values to zero. A correct solution would involve emulating vector
operations on denormalized values, but this has little effect on accuracy
and is much less complicated for now.

MFC after:	2 weeks
2010-10-05 18:08:07 +00:00
Nathan Whitehorn
6416b9a85d Split the SLB mirror cache into two kinds of object, one for kernel maps
which are similar to the previous ones, and one for user maps, which
are arrays of pointers into the SLB tree. This changes makes user SLB
updates atomic, closing a window for memory corruption. While here,
rearrange the allocation functions to make context switches faster.
2010-09-16 03:46:17 +00:00
Nathan Whitehorn
95fa3335e1 Replace the SLB backing store splay tree used on 64-bit PowerPC AIM
hardware with a lockless sparse tree design. This marginally improves
the performance of PMAP and allows copyin()/copyout() to run without
acquiring locks when used on wired mappings.

Submitted by:	mdf
2010-09-16 00:22:25 +00:00
John Baldwin
8c7a92bd4a Remove unused KTRACE includes. 2010-08-19 16:41:27 +00:00
Nathan Whitehorn
c3e289e1ce MFppc64:
Kernel sources for 64-bit PowerPC, along with build-system changes to keep
32-bit kernels compiling (build system changes for 64-bit kernels are
coming later). Existing 32-bit PowerPC kernel configurations must be
updated after this change to specify their architecture.
2010-07-13 05:32:19 +00:00
Konstantin Belousov
afe1a68827 Reorganize syscall entry and leave handling.
Extend struct sysvec with three new elements:
sv_fetch_syscall_args - the method to fetch syscall arguments from
  usermode into struct syscall_args. The structure is machine-depended
  (this might be reconsidered after all architectures are converted).
sv_set_syscall_retval - the method to set a return value for usermode
  from the syscall. It is a generalization of
  cpu_set_syscall_retval(9) to allow ABIs to override the way to set a
  return value.
sv_syscallnames - the table of syscall names.

Use sv_set_syscall_retval in kern_sigsuspend() instead of hardcoding
the call to cpu_set_syscall_retval().

The new functions syscallenter(9) and syscallret(9) are provided that
use sv_*syscall* pointers and contain the common repeated code from
the syscall() implementations for the architecture-specific syscall
trap handlers.

Syscallenter() fetches arguments, calls syscall implementation from
ABI sysent table, and set up return frame. The end of syscall
bookkeeping is done by syscallret().

Take advantage of single place for MI syscall handling code and
implement ptrace_lwpinfo pl_flags PL_FLAG_SCE, PL_FLAG_SCX and
PL_FLAG_EXEC. The SCE and SCX flags notify the debugger that the
thread is stopped at syscall entry or return point respectively.  The
EXEC flag augments SCX and notifies debugger that the process address
space was changed by one of exec(2)-family syscalls.

The i386, amd64, sparc64, sun4v, powerpc and ia64 syscall()s are
changed to use syscallenter()/syscallret(). MIPS and arm are not
converted and use the mostly unchanged syscall() implementation.

Reviewed by:	jhb, marcel, marius, nwhitehorn, stas
Tested by:	marcel (ia64), marius (sparc64), nwhitehorn (powerpc),
	stas (mips)
MFC after:	1 month
2010-05-23 18:32:02 +00:00
Nathan Whitehorn
a6b62947cf Allow user programs to execute mfpvr instructions. Linux allows this, and
some math-related software like GMP expects to be able to use it to pick
a target appropriately.

MFC after:	1 week
2010-02-22 14:17:23 +00:00
Alan Cox
e2997fea72 Simplify the invocation of vm_fault(). Specifically, eliminate the flag
VM_FAULT_DIRTY.  The information provided by this flag can be trivially
inferred by vm_fault().

Discussed with:	kib
2009-11-27 20:24:11 +00:00
Nathan Whitehorn
961e3d1410 Garbage collect some code that was never compiled in to handle Altivec
during traps. It predates actual Altivec support and was never used.
2009-11-22 20:45:15 +00:00
Konstantin Belousov
a7b890448c Extract the code that records syscall results in the frame into MD
function cpu_set_syscall_retval().

Suggested by:	marcel
Reviewed by:	marcel, davidxu
PowerPC, ARM, ia64 changes:	marcel
Sparc64 tested and reviewed by:	marius, also sunv reviewed
MIPS tested by:	gonzo
MFC after:	1 month
2009-11-10 11:43:07 +00:00
Nathan Whitehorn
2bbd567acb Garbage collect set_user_sr(), which is declared static inline and
never called.
2009-10-31 17:46:50 +00:00
Nathan Whitehorn
55fba05bf5 Fix a typo in the SRR1 comparison for program exceptions. While here,
replace magic numbers with constants to keep this from happening again.

Without this fix, some programs would occasionally get SIGTRAP instead
of SIGILL on an illegal instruction. This affected Altivec detection
in pixman, and possibly other software.

Reported by:	Andreas Tobler
MFC after:	1 week
2009-04-19 06:30:00 +00:00
Nathan Whitehorn
1ac37bcb77 Add Altivec support for supported CPUs. This is derived from the FPU support
code, and also reducing the size of trapcode to fit inside a 32 byte handler
slot.

Reviewed by:	grehan
MFC after:	2 weeks
2009-02-20 17:48:40 +00:00
Peter Grehan
aecb44179b Add link register to fatal trap printout to better diagnose NULL
function pointer derefs.
2008-06-04 07:32:49 +00:00
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
Rafal Jaworowski
786e4a1b04 Unify and generalize PowerPC headers, adjust AIM code accordingly.
Rework of this area is a pre-requirement for importing e500 support (and
other PowerPC core variations in the future). Mainly the following
headers are refactored so that we can cover for low-level differences between
various machines within PowerPC architecture:

  <machine/pcpu.h>
  <machine/pcb.h>
  <machine/kdb.h>
  <machine/hid.h>
  <machine/frame.h>

Areas which use the above are adjusted and cleaned up.

Credits for this rework go to marcel@

Approved by:	cognet (mentor)
MFp4:		e500
2008-03-02 17:05:57 +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
Julian Elischer
431f890614 generally we are interested in what thread did something as
opposed to what process. Since threads by default have teh name of the
process unless over-written with more useful information, just print the
thread name instead.
2007-11-14 06:21:24 +00:00
Marcel Moolenaar
0201e3e97b Remove redundant prototype.
Approved by: re (blanket)
2007-08-07 18:40:02 +00:00
Marcel Moolenaar
8875aa6621 Fix backward compatibility of the "old" (i.e. FreeBSD6) lseek
syscall. It was broken when a new lseek syscall was introduced.
The problem is that we need to swap the 32-bit td_retval values
for the __syscall indirect syscall when the actual syscall has
a 32-bit return value. Hence, we need to exclude lseek(2). And
this means the "old" lseek(2) as well -- which we didn't.

Based on a patch from: grehan@
Approved by: re (rwatson)
2007-07-31 06:23:26 +00:00
Attilio Rao
6759608248 Rework the PCPU_* (MD) interface:
- Rename PCPU_LAZY_INC into PCPU_INC
- Add the PCPU_ADD interface which just does an add on the pcpu member
  given a specific value.

Note that for most architectures PCPU_INC and PCPU_ADD are not safe.
This is a point that needs some discussions/work in the next days.

Reviewed by: alc, bde
Approved by: jeff (mentor)
2007-06-04 21:38:48 +00:00
Mohan Srinivasan
f9bb753844 Over NFS, an open() call could result in multiple over-the-wire
GETATTRs being generated - one from lookup()/namei() and the other
from nfs_open() (for cto consistency). This change eliminates the
GETATTR in nfs_open() if an otw GETATTR was done from the namei()
path. Instead of extending the vop interface, we timestamp each attr
load, and use this to detect whether a GETATTR was done from namei()
for this syscall. Introduces a thread-local variable that counts the
syscalls made by the thread and uses <pid, tid, thread syscalls> as
the attrload timestamp. Thanks to jhb@ and peter@ for a discussion on
thread state that could be used as the timestamp with minimal overhead.
2007-03-09 04:02:38 +00:00
John Birrell
8460a577a4 Make KSE a kernel option, turned on by default in all GENERIC
kernel configs except sun4v (which doesn't process signals properly
with KSE).

Reviewed by:	davidxu@
2006-10-26 21:42:22 +00:00
Robert Watson
ef0d1723db Add audit hooks for ppc, ia64 system call paths.
Reviewed by:	marcel (ia64)
Obtained from:	TrustedBSD Project
MFC after:	3 days
2006-09-16 17:03:02 +00:00
John Baldwin
cb76d9b05c Retire SYF_ARGMASK and remove both SYF_MPSAFE and SYF_ARGMASK. sy_narg is
now back to just being an argument count.
2006-07-28 20:22:58 +00:00
John Baldwin
af5bf12239 Now that all system calls are MPSAFE, retire the SYF_MPSAFE flag used to
mark system calls as being MPSAFE:
- Stop conditionally acquiring Giant around system call invocations.
- Remove all of the 'M' prefixes from the master system call files.
- Remove support for the 'M' prefix from the script that generates the
  syscall-related files from the master system call files.
- Don't explicitly set SYF_MPSAFE when registering nfssvc.
2006-07-28 19:05:28 +00:00
John Baldwin
22ea1bc57a Unify the checking for lock misbehavior in the various syscall()
implementations and adjust some of the checks while I'm here:
- Add a new check to make sure we don't return from a syscall in a critical
  section.
- Add a new explicit check before userret() to make sure we don't return
  with any locks held.  The advantage here is that we can include the
  syscall number and name in syscall() whereas that info is not available
  in userret().
- Drop the mtx_assert()'s of sched_lock and Giant.  They are replaced by
  the more general checks just added.

MFC after:	2 weeks
2006-07-27 22:32:30 +00:00
John Baldwin
00f1856905 Add missing ptrace(2) system-call stops to various syscall()
implementations.

MFC after:	1 week
2006-07-27 19:50:16 +00:00
Poul-Henning Kamp
eb2da9a51f Simplify system time accounting for profiling.
Rename struct thread's td_sticks to td_pticks, we will need the
other name for more appropriately named use shortly.  Reduce it
from uint64_t to u_int.

Clear td_pticks whenever we enter the kernel instead of recording
its value as reference for userret().  Use the absolute value of
td->pticks in userret() and eliminate third argument.
2006-02-08 08:09:17 +00:00
David Xu
9104847f21 1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most
changes in MD code are trivial, before this change, trapsignal and
   sendsig use discrete parameters, now they uses member fields of
   ksiginfo_t structure. For sendsig, this change allows us to pass
   POSIX realtime signal value to user code.

2. Remove cpu_thread_siginfo, it is no longer needed because we now always
   generate ksiginfo_t data and feed it to libpthread.

3. Add p_sigqueue to proc structure to hold shared signals which were
   blocked by all threads in the proc.

4. Add td_sigqueue to thread structure to hold all signals delivered to
   thread.

5. i386 and amd64 now return POSIX standard si_code, other arches will
   be fixed.

6. In this sigqueue implementation, pending signal set is kept as before,
   an extra siginfo list holds additional siginfo_t data for signals.
   kernel code uses psignal() still behavior as before, it won't be failed
   even under memory pressure, only exception is when deleting a signal,
   we should call sigqueue_delete to remove signal from sigqueue but
   not SIGDELSET. Current there is no kernel code will deliver a signal
   with additional data, so kernel should be as stable as before,
   a ksiginfo can carry more information, for example, allow signal to
   be delivered but throw away siginfo data if memory is not enough.
   SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can
   not be caught or masked.
   The sigqueue() syscall allows user code to queue a signal to target
   process, if resource is unavailable, EAGAIN will be returned as
   specification said.
   Just before thread exits, signal queue memory will be freed by
   sigqueue_flush.
   Current, all signals are allowed to be queued, not only realtime signals.

Earlier patch reviewed by: jhb, deischen
Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
Peter Grehan
ebc2aa7496 Temporary band-aid to fix hang when a process exec's Altivec instructions.
trap_subr.S:  declare a stub for the a-unavailable trap
              that does an absolute jump to the vector-assist trap.
              This is due to the fact that the vec-unavail trap
              doesn't start at a 256-byte boundary, so the trick of
              masking the bottom 8 bits of the link register to identify
              the interrupt doesn't work, so let the vec-assist
              case handle Altivec-disabled for the time being.

              Note that this will be fixed in the future with a much
              smaller vector code-stub (< 16 bytes) that will allow
              use of strange vector offsets that are also present in
              4xx processors, and also allow smaller differences in
              vector codepaths on the G5.

trap.c:       Treat altivec-unavailable/assist process traps as SIGILL.
              Not quite correct, since altivec-assist should really be a panic,
              but it is fine for the moment due to the above measure.

machdep.c     Install the stub code for the altivec-unavailable trap, and
              the standard trap code at the altivec-assist.

Reported by:	Andreas Tobler <toa at pop agri ch>
MFC after:	3 days
2005-07-30 11:14:31 +00:00
Paul Saab
8cb038b4b2 Don't enter the debugger if KDB_UNATTENDED is set or if
debug.debugger_on_panic=0.

MFC after:	2 weeks
2005-04-20 20:52:46 +00:00
John Baldwin
aa9aa68d2f Use PCPU_LAZY_INC() for cnt.v_{intr,trap,syscalls} rather than atomic
operations in some places and simple non-per CPU math in others.
2005-04-12 23:18:54 +00:00
Peter Grehan
bc54a0234a Include <sys/signalvar.h> for trapsignal prototype. 2005-03-15 11:41:55 +00:00
Warner Losh
60727d8b86 /* -> /*- for license, minor formatting changes 2005-01-07 02:29:27 +00:00
David Schultz
6004362e66 Don't include sys/user.h merely for its side-effect of recursively
including other headers.
2004-11-27 06:51:39 +00:00
Julian Elischer
5995adc206 Remove an unneeded argument..
The removed argument could trivially be derived from the remaining one.
That in turn should be the same as curthread, but it is possible that curthread could be expensive to derive on some syste,s so leave it as an argument.
Having both proc and thread as an argumen tjust gives an opportunity for
them to get out sync.

MFC after:	3 days
2004-08-31 07:34:54 +00:00
Julian Elischer
99e9dcb817 Remove sched_free_thread() which was only used
in diagnostics. It has outlived its usefulness and has started
causing panics for people who turn on DIAGNOSTIC, in what is otherwise
good code.

MFC after:	2 days
2004-08-31 06:12:13 +00:00
Peter Grehan
016927054b Kernel traps were not being passed to trap_fatal in some
circumstances.

Spotted by:  gallatin
2004-08-02 02:37:29 +00:00
Peter Grehan
b188ee2269 Bring into KDB new order. 2004-07-12 22:26:20 +00:00
Peter Grehan
077a0fb8b6 - correctly set the return value for the copyin/out fault buffer to 1
so setfault would return correctly when a page fault was invalid
  (e.g. a syscall with a bad parameter).

  This caused an endless DSI loop, seen when running sendmail which
  does a setlogin() call with a NULL pointer.

- introduce KTR_SYSC tracing. expose the syscallnames[] array to
  make the tracing more readable.
2004-07-09 11:00:41 +00:00
Peter Grehan
d0540ed535 - trailing white-space cleanup
- add call to thread_user_enter for P_SA processes before
  trap processing ala all other arches
2004-07-06 11:46:56 +00:00
Peter Grehan
e6bd8ae1e9 trap_pfault() shouldn't be acquiring Giant. Found to blow up
with MUTEX_PROFILING.

Submitted by:  Suleiman Souhlal <refugee@segfaulted.com>
2004-05-19 06:05:42 +00:00
John Baldwin
d90e753aa8 Range check the syscall number before looking it up in the syscallnames[]
array.

Submitted by:	pho
2003-04-30 17:59:27 +00:00