Commit Graph

72 Commits

Author SHA1 Message Date
Jaswinder Singh Rajput 88200bc28d x86: entry_32.S fix compile warnings - fix work mask bit width
Fix:

 arch/x86/kernel/entry_32.S:446: Warning: 00000000080001d1 shortened to 00000000000001d1
 arch/x86/kernel/entry_32.S:457: Warning: 000000000800feff shortened to 000000000000feff
 arch/x86/kernel/entry_32.S:527: Warning: 00000000080001d1 shortened to 00000000000001d1
 arch/x86/kernel/entry_32.S:541: Warning: 000000000800feff shortened to 000000000000feff
 arch/x86/kernel/entry_32.S:676: Warning: 0000000008000091 shortened to 0000000000000091

TIF_SYSCALL_FTRACE is 0x08000000 and until now we checked the
first 16 bits of the work mask - bit 27 falls outside of that.

Update the entry_32.S code to check the full 32-bit mask.

[ %cx => %ecx fix from Cyrill Gorcunov <gorcunov@gmail.com> ]

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "H. Peter Anvin" <hpa@kernel.org>
LKML-Reference: <1237012693.18733.3.camel@ht.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 09:42:51 +01:00
Stas Sergeev bda3a89745 x86: minor cleanup in the espfix code
Impact: Cleanup

Checkin be44d2aabc eliminates the use of
a 16-bit stack for espfix.  However, at least one instruction remained
that only operated on the low 16 bits of %esp.

This is not a bug per se because the kernel stack is always an aligned
4K or 8K block.  Therefore it cannot cross 64K boundaries; this code,
in fact, relies strictly on that fact.

However, it's a lot cleaner (and, for that matter, smaller) to operate
on the entire 32-bit register.

Signed-off-by: Stas Sergeev <stsp@aknet.ru>
CC: Zachary Amsden <zach@vmware.com>
CC: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-23 11:34:04 -08:00
Jeremy Fitzhardinge 0341c14da4 x86: use _types.h headers in asm where available
In general, the only definitions that assembly files can use
are in _types.S headers (where available), so convert them.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-13 11:35:01 -08:00
Ingo Molnar ab639f3593 Merge branch 'core/percpu' into x86/core 2009-02-13 09:45:09 +01:00
Brian Gerst 253f29a4ae x86: pass in pt_regs pointer for syscalls that need it
Some syscalls need to access the pt_regs structure, either to copy
user register state or to modifiy it.  This patch adds stubs to load
the address of the pt_regs struct into the %eax register, and changes
the syscalls to regparm(1) to receive the pt_regs pointer as the
first argument.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-11 12:40:45 +01:00
Tejun Heo 60a5317ff0 x86: implement x86_32 stack protector
Impact: stack protector for x86_32

Implement stack protector for x86_32.  GDT entry 28 is used for it.
It's set to point to stack_canary-20 and have the length of 24 bytes.
CONFIG_CC_STACKPROTECTOR turns off CONFIG_X86_32_LAZY_GS and sets %gs
to the stack canary segment on entry.  As %gs is otherwise unused by
the kernel, the canary can be anywhere.  It's defined as a percpu
variable.

x86_32 exception handlers take register frame on stack directly as
struct pt_regs.  With -fstack-protector turned on, gcc copies the
whole structure after the stack canary and (of course) doesn't copy
back on return thus losing all changed.  For now, -fno-stack-protector
is added to all files which contain those functions.  We definitely
need something better.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10 00:42:01 +01:00
Tejun Heo ccbeed3a05 x86: make lazy %gs optional on x86_32
Impact: pt_regs changed, lazy gs handling made optional, add slight
        overhead to SAVE_ALL, simplifies error_code path a bit

On x86_32, %gs hasn't been used by kernel and handled lazily.  pt_regs
doesn't have place for it and gs is saved/loaded only when necessary.
In preparation for stack protector support, this patch makes lazy %gs
handling optional by doing the followings.

* Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs.

* Save and restore %gs along with other registers in entry_32.S unless
  LAZY_GS.  Note that this unfortunately adds "pushl $0" on SAVE_ALL
  even when LAZY_GS.  However, it adds no overhead to common exit path
  and simplifies entry path with error code.

* Define different user_gs accessors depending on LAZY_GS and add
  lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS.  The
  lazy_*_gs() ops are used to save, load and clear %gs lazily.

* Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly.

xen and lguest changes need to be verified.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10 00:42:00 +01:00
Tejun Heo f0d96110f9 x86: use asm .macro instead of cpp #define in entry_32.S
Impact: cleanup

Use .macro instead of cpp #define where approriate.  This cleans up
code and will ease future changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10 00:41:57 +01:00
Ingo Molnar 1164dd0099 x86: move mach-default/*.h files to asm/
We are getting rid of subarchitecture support - move the hook files
to asm/. (These are now stale and should be replaced with more explicit
runtime mechanisms - but the transition is simpler this way.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-29 14:16:51 +01:00
Tejun Heo 02cf94c370 x86: make x86_32 use tlb_64.c
Impact: less contention when issuing invalidate IPI, cleanup

Make x86_32 use the same tlb code as 64bit.  The 64bit code uses
multiple IPI vectors for tlb shootdown to reduce contention.  This
patch makes x86_32 allocate the same 8 IPIs as x86_64 and share the
code paths.

Note that the usage of asmlinkage is inconsistent for x86_32 and 64
and calls for further cleanup.  This has been noted with a FIXME
comment in tlb_64.c.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-21 17:26:06 +09:00
Ingo Molnar e8cea892df Revert "i386: add TRACE_IRQS_OFF for the nmi"
This reverts commit e0c7317557.

This patch was wrong, as lockdep (and thus the irq state tracer)
aren't nmi safe. People are already seeing lockdep warnings due
to this.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-12 19:36:59 +01:00
Linus Torvalds b0f4b285d7 Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits)
  sched, trace: update trace_sched_wakeup()
  tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3
  Revert "x86: disable X86_PTRACE_BTS"
  ring-buffer: prevent false positive warning
  ring-buffer: fix dangling commit race
  ftrace: enable format arguments checking
  x86, bts: memory accounting
  x86, bts: add fork and exit handling
  ftrace: introduce tracing_reset_online_cpus() helper
  tracing: fix warnings in kernel/trace/trace_sched_switch.c
  tracing: fix warning in kernel/trace/trace.c
  tracing/ring-buffer: remove unused ring_buffer size
  trace: fix task state printout
  ftrace: add not to regex on filtering functions
  trace: better use of stack_trace_enabled for boot up code
  trace: add a way to enable or disable the stack tracer
  x86: entry_64 - introduce FTRACE_ frame macro v2
  tracing/ftrace: add the printk-msg-only option
  tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()
  x86, bts: correctly report invalid bts records
  ...

Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits
being already partly merged by the SH merge.
2008-12-28 12:21:10 -08:00
Steven Rostedt e49dc19c6a ftrace: function graph return for function entry
Impact: feature, let entry function decide to trace or not

This patch lets the graph tracer entry function decide if the tracing
should be done at the end as well. This requires all function graph
entry functions return 1 if it should trace, or 0 if the return should
not be traced.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-03 08:56:26 +01:00
Steven Rostedt bb4304c71c ftrace: have function graph use mcount caller address
Impact: consistency change for function graph

This patch makes function graph record the mcount caller address
the same way the function tracer does.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-03 08:56:22 +01:00
Ingo Molnar 3bdae4f464 Merge branch 'x86/debug' into x86/irq
We merge this branch because x86/debug touches code that we started
cleaning up in x86/irq. The two branches started out independent,
but as unexpected amount of activity went into x86/irq, they became
dependent. Resolve that by this cross-merge.
2008-11-28 15:00:48 +01:00
Alexander van Heukelum d211af055d i386: get rid of the use of KPROBE_ENTRY / KPROBE_END
entry_32.S is now the only user of KPROBE_ENTRY / KPROBE_END,
treewide. This patch reorders entry_64.S and explicitly generates
a separate section for functions that need the protection. The
generated code before and after the patch is equal.

The KPROBE_ENTRY and KPROBE_END macro's are removed too.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-27 12:37:54 +01:00
Steven Rostedt 5a45cfe1c6 ftrace: use code patching for ftrace graph tracer
Impact: more efficient code for ftrace graph tracer

This patch uses the dynamic patching, when available, to patch
the function graph code into the kernel.

This patch will ease the way for letting both function tracing
and function graph tracing run together.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-26 06:52:54 +01:00
Ingo Molnar c2324b694f tracing: function graph tracer, fix
fix return-tracer => graph-tracer namespace rename fallout.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-26 03:10:01 +01:00
Frederic Weisbecker fb52607afc tracing/function-return-tracer: change the name into function-graph-tracer
Impact: cleanup

This patch changes the name of the "return function tracer" into
function-graph-tracer which is a more suitable name for a tracing
which makes one able to retrieve the ordered call stack during
the code flow.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-26 01:59:45 +01:00
jia zhang 5f5db59132 x86, debug: remove the confusing entry in call trace
Impact: improve backtrace quality

avoid the confusion in call trace because of the lack of padding at the
tail of function.

When do_exit gets called, the return address behind call instruction is
pushed into stack. If something get wrong in do_exit, for x86_64, the
entry "kernel_execve +0x00/0xXX" rather than "child_rip +0xYY/0xZZ" is
in the call trace.

That looks confusing, so add a u2d to make the return address still part
of the original call site. (This also catches any instances of us returning
from that function somehow.)

Signed-off-by: jia zhang <jia.zhang2008@gmail.com>
Acked-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23 20:03:36 +01:00
Frederic Weisbecker e7d3737ea1 tracing/function-return-tracer: support for dynamic ftrace on function return tracer
This patch adds the support for dynamic tracing on the function return tracer.
The whole difference with normal dynamic function tracing is that we don't need
to hook on a particular callback. The only pro that we want is to nop or set
dynamically the calls to ftrace_caller (which is ftrace_return_caller here).

Some security checks ensure that we are not trying to launch dynamic tracing for
return tracing while normal function tracing is already running.

An example of trace with getnstimeofday set as a filter:

ktime_get_ts+0x22/0x50 -> getnstimeofday (2283 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1396 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1382 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1825 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1426 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1464 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1524 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1382 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1382 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1434 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1464 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1502 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1404 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1397 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1051 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1314 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1344 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1163 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1390 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1374 ns)

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-16 07:57:38 +01:00
Frederic Weisbecker 1dc1c6adf3 tracing/function-return-tracer: call prepare_ftrace_return by registers
Impact: Optimize a bit the function return tracer

This patch changes the calling convention of prepare_ftrace_return to
pass its arguments by register. This will optimize it a bit and
prepare it to support dynamic tracing.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12 23:15:43 +01:00
H. Peter Anvin 8665596ec0 x86: fix up the new IRQ code for older versions of gas
Older versions of gas don't implement the C-style != operator, they
instead want the Pascal-style <> operator.  Change != to <> so we
don't break compilation with those old versions of gas.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-12 10:27:35 -08:00
H. Peter Anvin b7c6244f13 x86: 32 bits: shrink and align IRQ stubs
Shrink the IRQ stubs on 32 bits down to just over four bytes per (we
fit seven into a 32-byte chunk.)  This shrinks the total icache
consumption of the IRQ stubs down to an even kilobyte, if all of them
are in active use.

The downside is that we end up with a double jump, which could have a
negative effect on some pipelines.  The double jump is always inside
the same cacheline on any modern chips (the exception being
486/Elan/Geode which have only 16-byte cachelines, but are unlikely to
have too many interrupt sources.)

To get the most effect, cache-align the IRQ stubs.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-11 13:24:58 -08:00
H. Peter Anvin 4687518c4c x86: 32 bit: interrupt stub consistency with 64 bit
Don't generate interrupt stubs for interrupt vectors below
FIRST_EXTERNAL_VECTOR, and make the table of interrupt vectors
(interrupt[]) __initconst.  Both of these changes both conserve memory
and improve consistency with 64 bits.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-11-11 13:03:07 -08:00
Frederic Weisbecker caf4b323b0 tracing, x86: add low level support for ftrace return tracing
Impact: add infrastructure for function-return tracing

Add low level support for ftrace return tracing.

This plug-in stores return addresses on the thread_info structure of
the current task.

The index of the current return address is initialized when the task
is the first one (init) and when a process forks (the child). It is
not needed when a task does a sys_execve because after this syscall,
it still needs to return on the kernel functions it called.

Note that the code of return_to_handler has been suggested by Steven
Rostedt as almost all of the ideas of improvements in this V3.

For purpose of security, arch/x86/kernel/process_32.c is not traced
because __switch_to() changes the current task during its execution.
That could cause inconsistency in the stored return address of this
function even if I didn't have any crash after testing with tracing on
this function enabled.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-11 10:29:11 +01:00
Steven Rostedt 60a7ecf426 ftrace: add quick function trace stop
Impact: quick start and stop of function tracer

This patch adds a way to disable the function tracer quickly without
the need to run kstop_machine. It adds a new variable called
function_trace_stop which will stop the calls to functions from mcount
when set.  This is just an on/off switch and does not handle recursion
like preempt_disable().

It's main purpose is to help other tracers/debuggers start and stop tracing
fuctions without the need to call kstop_machine.

The config option HAVE_FUNCTION_TRACE_MCOUNT_TEST is added for archs
that implement the testing of the function_trace_stop in the mcount
arch dependent code. Otherwise, the test is done in the C code.

x86 is the only arch at the moment that supports this.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-06 07:50:51 +01:00
Ingo Molnar 4944dd62de Merge commit 'v2.6.28-rc2' into tracing/urgent 2008-10-27 10:50:54 +01:00
Andi Kleen d2f6f7aeee MCE: Don't run 32bit machine checks with interrupts on
Running machine checks with interrupt on is a extremly bad idea. The machine
check handler only runs when the system is broken and needs to finish
as quickly as possible.

Remove the respective bogus post 2.6.27 regression and call
the machine check vector directly again.

This removes only code.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
[Cherry-picked from x86/mce]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-22 13:19:01 +02:00
Ingo Molnar debfcaf93e Merge branch 'tracing/ftrace' into tracing/urgent 2008-10-22 09:08:14 +02:00
Linus Torvalds 92b29b86fe Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (131 commits)
  tracing/fastboot: improve help text
  tracing/stacktrace: improve help text
  tracing/fastboot: fix initcalls disposition in bootgraph.pl
  tracing/fastboot: fix bootgraph.pl initcall name regexp
  tracing/fastboot: fix issues and improve output of bootgraph.pl
  tracepoints: synchronize unregister static inline
  tracepoints: tracepoint_synchronize_unregister()
  ftrace: make ftrace_test_p6nop disassembler-friendly
  markers: fix synchronize marker unregister static inline
  tracing/fastboot: add better resolution to initcall debug/tracing
  trace: add build-time check to avoid overrunning hex buffer
  ftrace: fix hex output mode of ftrace
  tracing/fastboot: fix initcalls disposition in bootgraph.pl
  tracing/fastboot: fix printk format typo in boot tracer
  ftrace: return an error when setting a nonexistent tracer
  ftrace: make some tracers reentrant
  ring-buffer: make reentrant
  ring-buffer: move page indexes into page headers
  tracing/fastboot: only trace non-module initcalls
  ftrace: move pc counter in irqtrace
  ...

Manually fix conflicts:
 - init/main.c: initcall tracing
 - kernel/module.c: verbose level vs tracepoints
 - scripts/bootgraph.pl: fallout from cherry-picking commits.
2008-10-20 13:35:07 -07:00
Steven Rostedt 606576ce81 ftrace: rename FTRACE to FUNCTION_TRACER
Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER.  The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.

This patch was generated mostly by script, and partially by hand.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-20 18:27:03 +02:00
Yinghai Lu 497c9a195d x86: make 32bit support per_cpu vector
so we can merge io_apic_32.c and io_apic_64.c

v2: Use cpu_online_map as target cpus for bigsmp, just like 64-bit is doing.

Also remove some unused TARGET_CPUS macro.

v3: need to check if desc is null in smp_irq_move_cleanup

also migration needs to reset vector too, so copy __target_IO_APIC_irq
from 64bit.

(the duplication will go away once the two files are unified.)

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:52:53 +02:00
Steven Rostedt 0a37605c22 ftrace: x86 mcount stub
x86 now sets up the mcount locations through the build and no longer
needs to record the ip when the function is executed. This patch changes
the initial mcount to simply return. There's no need to do any other work.
If the ftrace start up test fails, the original mcount will be what everything
will use, so having this as fast as possible is a good thing.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14 10:34:58 +02:00
Alexander van Heukelum a790392faa i386: add TRACE_IRQS_OFF for the exception 3 (int3)
At this point interrupts are off, so let's inform the tracing
code of that fact before calling into C.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:20:52 +02:00
Alexander van Heukelum e0c7317557 i386: add TRACE_IRQS_OFF for the nmi
At this point interrupts are off, so let's inform the tracing
code of that fact before calling into C.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:20:49 +02:00
Alexander van Heukelum 43024a8a5d i386: add TRACE_IRQS_OFF for exception 1 (debug)
At this point interrupts are off, so let's inform the tracing
code of that fact before calling into C.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:20:47 +02:00
Alexander van Heukelum 85cea51d7e i386: add TRACE_IRQS_OFF to entry_32.S in 'error_code'
Many exceptions use the same code path via the label 'error_code'
in entry_32.S. At this point interrupts are off, so let's inform
the tracing code of that fact before calling into C.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:20:45 +02:00
Alexander van Heukelum eb642f6208 i386: convert hardware exception 18 to an interrupt gate
Handle machine check exception with interrupt initially off.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:20:38 +02:00
Alexander van Heukelum 7643e9b936 i386: convert hardware exception 7 to an interrupt gate
Handle no coprocessor exception with interrupt initially off.

device_not_available in entry_32.S calls either math_state_restore
or math_emulate. This patch adds an extra indirection to be
able to re-enable interrupts explicitly in traps_32.c

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:20:17 +02:00
Roland McGrath af0575bba0 i386 syscall audit fast-path
This adds fast paths for 32-bit syscall entry and exit when
TIF_SYSCALL_AUDIT is set, but no other kind of syscall tracing.
These paths does not need to save and restore all registers as
the general case of tracing does.  Avoiding the iret return path
when syscall audit is enabled helps performance a lot.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-23 18:00:30 -07:00
Ingo Molnar acee709cab Merge branches 'x86/urgent', 'x86/amd-iommu', 'x86/apic', 'x86/cleanups', 'x86/core', 'x86/cpu', 'x86/fixmap', 'x86/gart', 'x86/kprobes', 'x86/memtest', 'x86/modules', 'x86/nmi', 'x86/pat', 'x86/reboot', 'x86/setup', 'x86/step', 'x86/unify-pci', 'x86/uv', 'x86/xen' and 'xen-64bit' into x86/for-linus 2008-07-21 16:37:17 +02:00
Jan Beulich 2ddf9b7b3e i386/xen: add proper unwind annotations to xen_sysenter_target
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-07-18 16:05:55 -07:00
Roland McGrath d4d6715016 x86 ptrace: unify syscall tracing
This unifies and cleans up the syscall tracing code on i386 and x86_64.

Using a single function for entry and exit tracing on 32-bit made the
do_syscall_trace() into some terrible spaghetti.  The logic is clear and
simple using separate syscall_trace_enter() and syscall_trace_leave()
functions as on 64-bit.

The unification adds PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP support
on x86_64, for 32-bit ptrace() callers and for 64-bit ptrace() callers
tracing either 32-bit or 64-bit tasks.  It behaves just like 32-bit.

Changing syscall_trace_enter() to return the syscall number shortens
all the assembly paths, while adding the SYSEMU feature in a simple way.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 12:15:17 -07:00
Roland McGrath 64f0973319 x86 ptrace: unify TIF_SINGLESTEP
This unifies the treatment of TIF_SINGLESTEP on i386 and x86_64.
The bit is now excluded from _TIF_WORK_MASK on i386 as it has been
on x86_64.  This means the do_notify_resume() path using it is never
used, so TIF_SINGLESTEP is not cleared on returning to user mode.

Both now leave TIF_SINGLESTEP set when returning to user, so that
it's already set on an int $0x80 system call entry.  This removes
the need for testing TF on the system_call path.  Doing it this way
fixes the regression for PTRACE_SINGLESTEP into a sigreturn syscall,
introduced by commit 1e2e99f0e4.

The clear_TF_reenable case that sets TIF_SINGLESTEP can only happen
on a non-exception kernel entry, i.e. sysenter/syscall instruction.
That will always get to the syscall exit tracing path.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 12:15:16 -07:00
Ingo Molnar 5806b81ac1 Merge branch 'auto-ftrace-next' into tracing/for-linus
Conflicts:

	arch/x86/kernel/entry_32.S
	arch/x86/kernel/process_32.c
	arch/x86/kernel/process_64.c
	arch/x86/lib/Makefile
	include/asm-x86/irqflags.h
	kernel/Makefile
	kernel/sched.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 16:11:52 +02:00
Glauber Costa 557d7d4e29 x86: use matching CFI_ENDPROC
The RING0_INT_FRAME macro defines a CFI_STARTPROC.
So we should really be using CFI_ENDPROC after it.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 20:49:28 +02:00
Jeremy Fitzhardinge d75cd22fdd x86/paravirt: split sysret and sysexit
Don't conflate sysret and sysexit; they're different instructions with
different semantics, and may be in use at the same time (at least
within the same kernel, depending on whether its an Intel or AMD
system).

sysexit - just return to userspace, does no register restoration of
    any kind; must explicitly atomically enable interrupts.

sysret - reloads flags from r11, so no need to explicitly enable
    interrupts on 64-bit, responsible for restoring usermode %gs

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citirx.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 13:13:15 +02:00
Abhishek Sagar 395a59d0f8 ftrace: store mcount address in rec->ip
Record the address of the mcount call-site. Currently all archs except sparc64
record the address of the instruction following the mcount call-site. Some
general cleanups are entailed. Storing mcount addresses in rec->ip enables
looking them up in the kprobe hash table later on to check if they're kprobe'd.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Cc: davem@davemloft.net
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-23 22:10:56 +02:00
Ingo Molnar d939d2851f Merge branch 'linus' into x86/irq 2008-06-16 11:27:45 +02:00