Commit Graph

34 Commits

Author SHA1 Message Date
Markos Chandras aebac99384 MIPS: kernel: entry.S: Set correct ISA level for mips_ihb
Commit 6ebb496ffc7e("MIPS: kernel: entry.S: Add MIPS R6 related
definitions") added the MIPSR6 definition but it did not update the
ISA level of the actual assembly code so a pre-MIPSR6 jr.hb instruction
was generated instead. Fix this by using the MISP_ISA_LEVEL_RAW macro.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Fixes: 6ebb496ffc7e("MIPS: kernel: entry.S: Add MIPS R6 related definitions")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9386/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-10 15:41:46 +02:00
Markos Chandras 7c151d3d5d MIPS: Make use of the ERETNC instruction on MIPS R6
The ERETNC instruction, introduced in MIPS R5, is similar to the ERET
one, except it does not clear the LLB bit in the LLADDR register.
This feature is necessary to safely emulate R2 LL/SC instructions.
However, on context switches, we need to clear the LLAddr/LLB bit
in order to make sure that an SC instruction from the new thread
will never succeed if it happens to interrupt an LL operation on the
same address from the previous thread.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:37 +00:00
Markos Chandras 6ebb496ffc MIPS: kernel: entry.S: Add MIPS R6 related definitions
The instruction hazard barrier in the form of:

jr.hb	ra
nop

is valid on MIPS R6 as well.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17 15:37:26 +00:00
Ralf Baechle b633648c5a MIPS: MT: Remove SMTC support
Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-24 00:07:01 +02:00
Linus Torvalds 9977d9b379 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull big execve/kernel_thread/fork unification series from Al Viro:
 "All architectures are converted to new model.  Quite a bit of that
  stuff is actually shared with architecture trees; in such cases it's
  literally shared branch pulled by both, not a cherry-pick.

  A lot of ugliness and black magic is gone (-3KLoC total in this one):

   - kernel_thread()/kernel_execve()/sys_execve() redesign.

     We don't do syscalls from kernel anymore for either kernel_thread()
     or kernel_execve():

     kernel_thread() is essentially clone(2) with callback run before we
     return to userland, the callbacks either never return or do
     successful do_execve() before returning.

     kernel_execve() is a wrapper for do_execve() - it doesn't need to
     do transition to user mode anymore.

     As a result kernel_thread() and kernel_execve() are
     arch-independent now - they live in kernel/fork.c and fs/exec.c
     resp.  sys_execve() is also in fs/exec.c and it's completely
     architecture-independent.

   - daemonize() is gone, along with its parts in fs/*.c

   - struct pt_regs * is no longer passed to do_fork/copy_process/
     copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.

   - sys_fork()/sys_vfork()/sys_clone() unified; some architectures
     still need wrappers (ones with callee-saved registers not saved in
     pt_regs on syscall entry), but the main part of those suckers is in
     kernel/fork.c now."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
  do_coredump(): get rid of pt_regs argument
  print_fatal_signal(): get rid of pt_regs argument
  ptrace_signal(): get rid of unused arguments
  get rid of ptrace_signal_deliver() arguments
  new helper: signal_pt_regs()
  unify default ptrace_signal_deliver
  flagday: kill pt_regs argument of do_fork()
  death to idle_regs()
  don't pass regs to copy_process()
  flagday: don't pass regs to copy_thread()
  bfin: switch to generic vfork, get rid of pointless wrappers
  xtensa: switch to generic clone()
  openrisc: switch to use of generic fork and clone
  unicore32: switch to generic clone(2)
  score: switch to generic fork/vfork/clone
  c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
  take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
  mn10300: switch to generic fork/vfork/clone
  h8300: switch to generic fork/vfork/clone
  tile: switch to generic clone()
  ...

Conflicts:
	arch/microblaze/include/asm/Kbuild
2012-12-12 12:22:13 -08:00
Dmitry Adamushko c90e6fbb22 MIPS: Fix endless loop when processing signals for kernel tasks
The problem occurs [1] when a kernel-mode task returns from a system
call with a pending signal.

A real-life scenario is a child of 'khelper' returning from a failed
kernel_execve() in ____call_usermodehelper() [ kernel/kmod.c ].
kernel_execve() fails due to a pending SIGKILL, which is the result of
"kill -9 -1" (at least, busybox's init does it upon reboot).

The loop is as follows:

* syscall_exit_work:
 - work_pending:            // start_of_the_loop
 - work_notifysig:
   - do_notify_resume()
     - do_signal()
       - if (!user_mode(regs)) return;
 - resume_userspace         // TIF_SIGPENDING is still set
 - work_pending             // so we call work_pending => goto
                            // start_of_the_loop

More information can be found in another LKML thread:
http://www.serverphorums.com/read.php?12,457826

[1] The problem was also reproduced on !CONFIG_VM86 x86, and the
following fix was accepted.

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=29a2e2836ff9ea65a603c89df217f4198973a74f

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3571/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-12-05 19:59:00 +01:00
Al Viro 9b0e5d42d9 mips: switch to saner kernel_execve() semantics
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-15 16:27:52 -04:00
Ralf Baechle baf9ff74ed MIPS: Switch over to generic sys_execve and kernel_execve.
This version contains a few updates by David Daney, in particular it's
now using __builtin_frame_address() instead of asm() which depending
on personal taste, is slightly more appealing.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-14 19:31:30 -04:00
Al Viro 8f54bcacbc mips: switch to generic kernel_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-14 19:30:25 -04:00
Al Viro 02f884ed46 MIPS: Merge the identical "return from syscall" per-ABI code
No need to keep 4 copies of that stuff; merged and taken to
entry.S, unused public symbols there killed off.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-09-22 15:47:31 +02:00
Al Viro f76f330809 MIPS: Prevent hitting do_notify_resume() with !user_mode(regs).
Too late to do anything there...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-09-22 15:47:11 +02:00
Ralf Baechle 8b659a3931 MIPS: Split do_syscall_trace into two functions.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-19 09:55:44 +01:00
Ralf Baechle c19c20ac63 MIPS: Use single define for pending work on syscall exit
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-05-19 09:55:44 +01:00
Kevin D. Kissell d2bb01b042 [MIPS] SMTC: Close tiny holes in the SMTC IPI replay system.
Signed-off-by: Kevin D. Kissell <kevink@paralogos.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-10-03 17:58:58 +01:00
Kevin D. Kissell 0db34215c7 [MIPS] SMTC: Interrupt mask backstop hack
To support multiple TC microthreads acting as "CPUs" within a VPE,
VPE-wide interrupt mask bits must be specially manipulated during
interrupt handling. To support legacy drivers and interrupt controller
management code, SMTC has a "backstop" to track and if necessary restore
the interrupt mask. This has some performance impact on interrupt service
overhead. Disable it only if you know what you are doing.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-07-12 17:41:17 +01:00
Chris Dearman cbde5ebc97 [MIPS] lockdep: Handle interrupts in R3000 style c0_status register.
Check the IEP bit for R3000 style processors when checking to see if
interrupts will be reenabled in restore_all.

Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Franck Bui-Huu 7da8a581f5 [MIPS] Make entry.S a little more readable.
When CONFIG_PREEMPT is not set, it also moves one branch instruction from
ret_from_irq() to ret_from_exception().  Therefore we favour the return
from irq case which should be more common than the other one.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-02-13 22:40:51 +00:00
Ralf Baechle cb56837ea5 [MIPS] SMTC: Fix crash if # of TC's > # of VPE's after pt_regs irq cleanup.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-01 17:46:09 +00:00
Atsushi Nemoto f431baa55a [MIPS] ret_from_irq adjustment
Make sure that RA on top of interrupt stack is an address of ret_from_irq,
so that dump_stack etc. can trace info interrupted context.

Also this patch fixes except_vec_vi_handler and __smtc_ipi_vector which
seems broken.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-09 23:20:46 +01:00
Ralf Baechle 937a801576 [MIPS] Complete fixes after removal of pt_regs argument to int handlers.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-08 02:38:28 +01:00
Ralf Baechle 192ef36619 [MIPS] TRACE_IRQFLAGS_SUPPORT support.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-07-13 21:26:09 +01:00
Ingo Molnar 36c8b58689 [PATCH] sched: cleanup, remove task_t, convert to struct task_struct
cleanup: remove task_t and convert all the uses to struct task_struct. I
introduced it for the scheduler anno and it was a mistake.

Conversion was mostly scripted, the result was reviewed and all
secondary whitespace and style impact (if any) was fixed up by hand.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:11 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Ralf Baechle 4277ff5ee5 [MIPS] Fix use of ehb instruction for non-R2 configurations.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-06-29 21:10:49 +01:00
Ralf Baechle 477654fc5d [MIPS] Fix typo
Found by Chris Dearman (chris@mips.com).

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-06-01 00:28:29 +01:00
Ralf Baechle 41c594ab65 [MIPS] MT: Improved multithreading support.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-04-19 04:14:28 +02:00
Ralf Baechle bce1a28686 [MIPS] R2: Instruction hazard barrier.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-04-19 04:14:22 +02:00
Ralf Baechle 93373ed4d8 [MIPS] Rewrite spurious_interrupt from assembler to C.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-04-19 04:14:18 +02:00
Ralf Baechle 0bf0e3e279 Fix excessive signal latencies.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:32:23 +01:00
Ralf Baechle cdaed73afb Fix preemption bug.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:30:51 +01:00
Ralf Baechle a18815abcd Use preempt_schedule_irq.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:30:27 +01:00
Thiemo Seufer c264852726 Remove unused arguments from preempt_{start,stop}/local_irq_{en,dis}able.
Don't clobber the preloaded TI_FLAGS in a2 needlessly.
Unexport local functions.

Signed-off-by: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:30:16 +01:00
Thiemo Seufer b59a9504cb De-optimize and decomplicate the spurious interrupt handler.
Signed-off-by: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:30:15 +01:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00