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6 commits

Author SHA1 Message Date
Paul Mackerras
1bd79336a4 powerpc: Fix various syscall/signal/swapcontext bugs
A careful reading of the recent changes to the system call entry/exit
paths revealed several problems, plus some things that could be
simplified and improved:

* 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit
  path, so it was only doing anything with it once it saw some other
  bit being set.  In other words, the noerror behaviour would apply to
  the next system call where we had to reschedule or deliver a signal,
  which is not necessarily the current system call.

* 32-bit wasn't doing the call to ptrace_notify in the syscall exit
  path when the _TIF_SINGLESTEP bit was set.

* _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and
  _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set
  by system calls.  I took it out of _TIF_USER_WORK_MASK.

* On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers
  to be restored (unless perhaps a signal was delivered or the syscall
  was traced or single-stepped).  Thus the non-volatile registers
  weren't restored on exit from a signal handler.  We probably got
  away with it mostly because signal handlers written in C wouldn't
  alter the non-volatile registers.

* On 32-bit I simplified the code and made it more like 64-bit by
  making the syscall exit path jump to ret_from_except to handle
  preemption and signal delivery.

* 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was
  set - but I think because of that 32-bit was actually restoring the
  non-volatile registers on exit from a signal handler.

* I changed the order of enabling interrupts and saving the
  non-volatile registers before calling do_syscall_trace_leave; now we
  enable interrupts first.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 13:24:22 +11:00
Paul Mackerras
21a6290220 powerpc: move include/asm-ppc64/ptrace-common.h to arch/powerpc/kernel
It's only used by arch/powerpc/kernel/ptrace{,32}.c.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-19 20:47:22 +11:00
Christoph Hellwig
481bed4542 [PATCH] consolidate sys_ptrace()
The sys_ptrace boilerplate code (everything outside the big switch
statement for the arch-specific requests) is shared by most architectures.
This patch moves it to kernel/ptrace.c and leaves the arch-specific code as
arch_ptrace.

Some architectures have a too different ptrace so we have to exclude them.
They continue to keep their implementations.  For sh64 I had to add a
sh64_ptrace wrapper because it does some initialization on the first call.
For um I removed an ifdefed SUBARCH_PTRACE_SPECIAL block, but
SUBARCH_PTRACE_SPECIAL isn't defined anywhere in the tree.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-By: David Howells <dhowells@redhat.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:42 -08:00
Paul Mackerras
734d652480 powerpc: apply recent changes to merged code
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-31 13:57:01 +11:00
Paul Mackerras
b123923d48 powerpc: Move ptrace32.c from arch/ppc64 to arch/powerpc
Also corrected my email address in ptrace.c and updated the comments
at the top of ptrace32.c.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-20 09:11:29 +10:00
Stephen Rothwell
e8a30302ab powerpc: merge ptrace.c
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
2005-10-13 15:52:04 +10:00
Renamed from arch/ppc/kernel/ptrace.c (Browse further)