Commit Graph

44 Commits

Author SHA1 Message Date
Jan Beulich c33bd9aac0 [PATCH] i386/x86-64: fall back to old-style call trace if no unwinding
If no unwinding is possible at all for a certain exception instance,
fall back to the old style call trace instead of not showing any trace
at all.

Also, allow setting the stack trace mode at the command line.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:18 -07:00
Jan Beulich 176a2718f4 [PATCH] i386: reliable stack trace support (i386)
These are the i386-specific pieces to enable reliable stack traces. This is
going to be even more useful once CFI annotations get added to he assembly
code, namely to entry.S.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:17 -07:00
Chuck Ebbert 7e04a1183e [PATCH] i386: extra checks in show_registers()
Sometimes thread_info and task_struct get out-of-sync with each other.
Printing task.thread_info in show_registers() can help spot this.  And when
task_struct is corrupt then task.comm can contain garbage, so only print as
many characters as it can hold.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:59 -07:00
Ingo Molnar b88d4f1d39 [PATCH] i386: break out of recursion in stackframe walk
If CONFIG_FRAME_POINTERS is enabled, and one does a dump_stack() during
early SMP init, an infinite stackdump and a bootup hang happens:

 [<c0104e7f>] show_trace+0xd/0xf
 [<c0104e96>] dump_stack+0x15/0x17
 [<c01440df>] save_trace+0xc3/0xce
 [<c014527d>] mark_lock+0x8c/0x4fe
 [<c0145df5>] __lockdep_acquire+0x44e/0xaa5
 [<c0146798>] lockdep_acquire+0x68/0x84
 [<c1048699>] _spin_lock+0x21/0x2f
 [<c010d918>] prepare_set+0xd/0x5d
 [<c010daa8>] generic_set_all+0x1d/0x201
 [<c010ca9a>] mtrr_ap_init+0x23/0x3b
 [<c010ada8>] identify_cpu+0x2a7/0x2af
 [<c01192a7>] smp_store_cpu_info+0x2f/0xb4
 [<c01197d0>] start_secondary+0xb5/0x3ec
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [<c104ec11>] end_of_stack_stop_unwind_function+0x1/0x4
 [...]

Due to "end_of_stack_stop_unwind_function" recursing back to itself in the
EBP stackframe-walker.  So avoid this type of recursion when walking the
stack .

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:56 -07:00
Chuck Ebbert c44b20d511 [PATCH] i386: remove junk from stack dump
i386 stack dump has a "<0>" in the middle of the line and an extra space
between columns in multicolumn mode.  Remove those and also remove an extra
blank line of source code.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-21 12:59:16 -07:00
Randy Dunlap 7bee5c0fd2 [PATCH] i386: print EIP/ESP last
Print summary registers (EIP and SS:ESP only) as last death info.  This
makes this important data visible in case it had scrolled off the top of
the display.  Similar to what x86_64 does.  Suggested by Andi Kleen.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:33 -07:00
OGAWA Hirofumi 9b41046cd0 [PATCH] Don't pass boot parameters to argv_init[]
The boot cmdline is parsed in parse_early_param() and
parse_args(,unknown_bootoption).

And __setup() is used in obsolete_checksetup().

	start_kernel()
		-> parse_args()
			-> unknown_bootoption()
				-> obsolete_checksetup()

If __setup()'s callback (->setup_func()) returns 1 in
obsolete_checksetup(), obsolete_checksetup() thinks a parameter was
handled.

If ->setup_func() returns 0, obsolete_checksetup() tries other
->setup_func().  If all ->setup_func() that matched a parameter returns 0,
a parameter is seted to argv_init[].

Then, when runing /sbin/init or init=app, argv_init[] is passed to the app.
If the app doesn't ignore those arguments, it will warning and exit.

This patch fixes a wrong usage of it, however fixes obvious one only.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:53 -08:00
Alan Stern e041c68341 [PATCH] Notifier chain update: API changes
The kernel's implementation of notifier chains is unsafe.  There is no
protection against entries being added to or removed from a chain while the
chain is in use.  The issues were discussed in this thread:

    http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2

We noticed that notifier chains in the kernel fall into two basic usage
classes:

	"Blocking" chains are always called from a process context
	and the callout routines are allowed to sleep;

	"Atomic" chains can be called from an atomic context and
	the callout routines are not allowed to sleep.

We decided to codify this distinction and make it part of the API.  Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name).  New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain.  The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.

With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed.  For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections.  (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)

There are some limitations, which should not be too hard to live with.  For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem.  Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain.  (This did happen in a couple of places and the code
had to be changed to avoid it.)

Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization.  Instead we use RCU.  The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.

Here is the list of chains that we adjusted and their classifications.  None
of them use the raw API, so for the moment it is only a placeholder.

  ATOMIC CHAINS
  -------------
arch/i386/kernel/traps.c:		i386die_chain
arch/ia64/kernel/traps.c:		ia64die_chain
arch/powerpc/kernel/traps.c:		powerpc_die_chain
arch/sparc64/kernel/traps.c:		sparc64die_chain
arch/x86_64/kernel/traps.c:		die_chain
drivers/char/ipmi/ipmi_si_intf.c:	xaction_notifier_list
kernel/panic.c:				panic_notifier_list
kernel/profile.c:			task_free_notifier
net/bluetooth/hci_core.c:		hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_expect_chain
net/ipv6/addrconf.c:			inet6addr_chain
net/netfilter/nf_conntrack_core.c:	nf_conntrack_chain
net/netfilter/nf_conntrack_core.c:	nf_conntrack_expect_chain
net/netlink/af_netlink.c:		netlink_chain

  BLOCKING CHAINS
  ---------------
arch/powerpc/platforms/pseries/reconfig.c:	pSeries_reconfig_chain
arch/s390/kernel/process.c:		idle_chain
arch/x86_64/kernel/process.c		idle_notifier
drivers/base/memory.c:			memory_chain
drivers/cpufreq/cpufreq.c		cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c		cpufreq_transition_notifier_list
drivers/macintosh/adb.c:		adb_client_list
drivers/macintosh/via-pmu.c		sleep_notifier_list
drivers/macintosh/via-pmu68k.c		sleep_notifier_list
drivers/macintosh/windfarm_core.c	wf_client_list
drivers/usb/core/notify.c		usb_notifier_list
drivers/video/fbmem.c			fb_notifier_list
kernel/cpu.c				cpu_chain
kernel/module.c				module_notify_list
kernel/profile.c			munmap_notifier
kernel/profile.c			task_exit_notifier
kernel/sys.c				reboot_notifier_list
net/core/dev.c				netdev_chain
net/decnet/dn_dev.c:			dnaddr_chain
net/ipv4/devinet.c:			inetaddr_chain

It's possible that some of these classifications are wrong.  If they are,
please let us know or submit a patch to fix them.  Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)

The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.

[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:50 -08:00
Jan Beulich 20c0d2d440 [PATCH] i386: pass proper trap numbers to die chain handlers
Pass the trap number causing the call to notify_die() to the die
notification handler chain in a number of instances.  Also, honor the
return value from the handler chain invocation in die() as, through a
debugger, the fault may have been fixed.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-By: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:53 -08:00
Andrew Morton dd287796d6 [PATCH] pause_on_oops command line option
Attempt to fix the problem wherein people's oops reports scroll off the screen
due to repeated oopsing or to oopses on other CPUs.

If this happens the user can reboot with the `pause_on_oops=<seconds>' option.
It will allow the first oopsing CPU to print an oops record just a single
time.  Second oopsing attempts, or oopses on other CPUs will cause those CPUs
to enter a tight loop until the specified number of seconds have elapsed.

The patch implements the infrastructure generically in the expectation that
architectures other than x86 will find it useful.

Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:16 -08:00
Chuck Ebbert 75874d5cc8 [PATCH] i386: fix dump_stack()
i386 has a small bug in the stack dump code where it prints an extra log
level code.  Remove that and fix the alignment of normal stack dump
printout.  Also remove some unnecessary printk() calls.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:06 -08:00
Jan Beulich db753bdfc2 [PATCH] i386: fix uses of user_mode() vs. user_mode_vm()
>commit 76381fee7e
>Author: Vincent Hanquez <vincent.hanquez@cl.cam.ac.uk>
>Date:   Thu Jun 23 00:08:46 2005 -0700
>
>    [PATCH] xen: x86_64: use more usermode macro
>
>    Make use of the user_mode macro where it's possible.  This is useful for Xen
>    because it will need only to redefine only the macro to a hypervisor call.

I am of the opinion that the above changeset is incomplete, i.e.  it missed
converting some previous uses of user_mode to user_mode_vm.  While most of
them could be considered just cosmetical, at least the one in die_nmi
doesn't appear to be.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Vincent Hanquez <vincent.hanquez@cl.cam.ac.uk>
Cc: Zachary Amsden <zach@vmware.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:05 -08:00
Jan Beulich 101f12af16 [PATCH] i386: actively synchronize vmalloc area when registering certain callbacks
Registering a callback handler through register_die_notifier() is obviously
primarily intended for use by modules.  However, the way these currently
get called it is basically impossible for them to actually be used by
modules, as there is, on non-PAE configurationes, a good chance (the larger
the module, the better) for the system to crash as a result.

This is because the callback gets invoked

(a) in the page fault path before the top level page table propagation
    gets carried out (hence a fault to propagate the top level page table
    entry/entries mapping to module's code/data would nest infinitly) and

(b) in the NMI path, where nested faults must absolutely not happen,
    since otherwise the IRET from the nested fault re-enables NMIs,
    potentially resulting in nested NMI occurences.

Besides the modular aspect, similar problems would even arise for in-
kernel consumers of the API if they touched ioremap()ed or vmalloc()ed
memory inside their handlers.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:05 -08:00
Jean Delvare cc04ee9cc5 [PATCH] i386 traps: merge printk calls
Merge a few printk calls in i386 traps.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:04 -08:00
Chuck Ebbert 4d7d8c82c1 [PATCH] i386: multi-column stack backtraces
Print stack backtraces in multiple columns, saving screen space.  Number of
columns is configurable and defaults to one so behavior is
backwards-compatible.

Also removes the brackets around addresses when printing more
that one entry per line so they print as:
    <address>
instead of:
    [<address>]
This helps multiple entries fit better on one line.

Original idea by Dave Jones, taken from x86_64.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:03 -08:00
Chuck Ebbert b53e8f68e0 [PATCH] i386: print kernel version in register dumps
Show first field of kernel version in register dumps like x86_64 does.

Changes output from e.g.:
	(2.6.16-rc1)
to:
	(2.6.16-rc1 #12)

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-05 11:06:53 -08:00
Hugh Dickins 165a2c1d51 [PATCH] x86: fix stack trace facility level
dump_stack() on page allocation failure presently has an irritating habit
of shouting just "====" at everyone: please stop it.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-05 11:06:52 -08:00
Chuck Ebbert 7aa89746e8 [PATCH] i386: fix stack dump loglevel
Recent changes caused part of stack traces from SysRq-T to print at
KERN_EMERG loglevel.  Also, parts of stack dump during oops were failing to
print at that level when they should.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:07 -08:00
Dave Jones 9c107805ab [PATCH] printk levels for i386 oops code.
Especially useful when users have booted with 'quiet'.  In the regular 'oops'
path, we set the console_loglevel before we start spewing debug info, but we
can call the backtrace code from other places now too, such as the spinlock
debugging code.

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:25 -08:00
Jan Beulich eb05c3249a [PATCH] i386: fix bound check IDT gate
Other than apparently commonly assumed, the bound instruction does not
require the corresponding IDT entry to have DPL 3.

Acked-by: "Seth, Rohit" <rohit.seth@intel.com>
Acked-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:34 -08:00
Jan Beulich d43c6e8083 [PATCH] i386: move SIMD initialization
Move some code unrelated to any dealing with hardware bugs from i386's
bugs.h to a more logical place.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:34 -08:00
Jan Beulich e43d674f44 [PATCH] i386: don't blindly enable interrupts in die()
Rather than blindly re-enabling interrupts in die(), save their state
upon entry and then restore that state.

If the kernel is in really bad condition and faults with interrupts disabled,
re-enabling them in die() may cause even more trouble, implying more chances
of data corruption.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:34 -08:00
Chuck Ebbert 631b034724 [PATCH] i386: "invalid operand" -> "invalid opcode"
According to the manual, INT 6 is "invalid opcode", not "invalid operand".

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-04 16:47:42 -08:00
Shaohua Li 82584ef75b [PATCH] x86: fix NMI with CPU hotplug
With CPU hotplug enabled, NMI watchdog stoped working.  It appears the
violation is the cpu_online check in nmi handler.  local ACPI based NMI
watchdog is initialized before we set CPU online for APs.  It's quite
possible a NMI is fired before we set CPU online, and that's what happens
here.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-12 08:57:42 -08:00
Bart Oldeman d5cd4aadd3 [PATCH] x86: initialise tss->io_bitmap_owner to something
There exists a field io_bitmap_owner in the TSS that is only checked, but
never set to anything else but NULL.

Signed-off-by: Bart Oldeman <bartoldeman@users.sourceforge.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:11 -08:00
Al Viro ce3a161e69 [PATCH] useless includes of linux/irq.h in arch/i386
Most of these guys are simply not needed (pulled by other stuff
via asm-i386/hardirq.h).  One that is not entirely useless is hilarious -
arch/i386/oprofile/nmi_timer_int.c includes linux/irq.h... as a way to
get linux/errno.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-26 18:29:50 -07:00
Chuck Ebbert 33333373c4 [PATCH] i386: Ignore masked FPU exceptions
Masked FPU exceptions should obviously not happen in the first place,
but if they do, ignoring them seems to be the right thing to do.

Although there is no documentation available for Cyrix MII, I did find
erratum F-7 for Winchip C6, "FPU instruction may result in spurious
exception under certain conditions" which seems to indicate that this
can happen.

That would also explain the behaviour Ondrej Zary reported on the MII.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-13 09:59:04 -07:00
Prasanna S Panchamukhi 3d97ae5b95 [PATCH] kprobes: prevent possible race conditions i386 changes
This patch contains the i386 architecture specific changes to prevent the
possible race conditions.

Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:59 -07:00
Paul E. McKenney 19306059cd [PATCH] NMI: Update NMI users of RCU to use new API
Uses of RCU for dynamically changeable NMI handlers need to use the new
rcu_dereference() and rcu_assign_pointer() facilities.  This change makes
it clear that these uses are safe from a memory-barrier viewpoint, but the
main purpose is to document exactly what operations are being protected by
RCU.  This has been tested on x86 and x86-64, which are the only
architectures affected by this change.

Signed-off-by: <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:19 -07:00
George Anzinger 748f2edb52 [PATCH] x86 NMI: better support for debuggers
This patch adds a notify to the die_nmi notify that the system is about to
be taken down.  If the notify is handled with a NOTIFY_STOP return, the
system is given a new lease on life.

We also change the nmi watchdog to carry on if die_nmi returns.

This give debug code a chance to a) catch watchdog timeouts and b) possibly
allow the system to continue, realizing that the time out may be due to
debugger activities such as single stepping which is usually done with
"other" cpus held.

Signed-off-by: George Anzinger<george@mvista.com>
Cc: Keith Owens <kaos@ocs.com.au>
Signed-off-by: George Anzinger <george@mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:13 -07:00
Zachary Amsden 0998e4228a [PATCH] x86: privilege cleanup
Privilege checking cleanup.  Originally, these diffs were much greater, but
recent cleanups in Linux have already done much of the cleanup.  I added
some explanatory comments in places where the reasoning behind certain
tests is rather subtle.

Also, in traps.c, we can skip the user_mode check in handle_BUG().  The
reason is, there are only two call chains - one via die_if_kernel() and one
via do_page_fault(), both entering from die().  Both of these paths already
ensure that a kernel mode failure has happened.  Also, the original check
here, if (user_mode(regs)) was insufficient anyways, since it would not
rule out BUG faults from V8086 mode execution.

Saving the %ss segment in show_regs() rather than assuming a fixed value
also gives better information about the current kernel state in the
register dump.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:12 -07:00
Zachary Amsden 4d37e7e3fd [PATCH] i386: inline assembler: cleanup and encapsulate descriptor and task register management
i386 inline assembler cleanup.

This change encapsulates descriptor and task register management.  Also,
it is possible to improve assembler generation in two cases; savesegment
may store the value in a register instead of a memory location, which
allows GCC to optimize stack variables into registers, and MOV MEM, SEG
is always a 16-bit write to memory, making the casting in math-emu
unnecessary.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:11 -07:00
Chuck Ebbert b1daec3089 [PATCH] i386: fix incorrect FP signal code
i386 floating-point exception handling has a bug that can cause error
code 0 to be sent instead of the proper code during signal delivery.

This is caused by unconditionally checking the IS and c1 bits from the
FPU status word when they are not always relevant.  The IS bit tells
whether an exception is a stack fault and is only relevant when the
exception is IE (invalid operation.) The C1 bit determines whether a
stack fault is overflow or underflow and is only relevant when IS and IE
are set.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-23 19:52:37 -07:00
Domen Puncer 3f3ae3471f [PATCH] arch/i386/kernel/traps.c: fix sparse warnings
Signed-off-by: Alexey Dobriyan <adobriyan@mail.ru>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:58 -07:00
Alexander Nyberg 4f339ecb30 [PATCH] kdump: Save trap information for later analysis
If we are faulting in kernel it is quite possible this will lead to a
panic.  Save trap number, cr2 (in case of page fault) and error_code in the
current thread (these fields already exist for signal delivery but are not
used here).

This helps later kdump crash analyzing from user-space (a script has been
submitted to dig this info out in gdb).

Signed-off-by: Alexander Nyberg <alexn@telia.com>
Cc: <fastboot@lists.osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:55 -07:00
Alexander Nyberg 6e274d1443 [PATCH] kdump: Use real pt_regs from exception
Makes kexec_crashdump() take a pt_regs * as an argument.  This allows to
get exact register state at the point of the crash.  If we come from direct
panic assertion NULL will be passed and the current registers saved before
crashdump.

This hooks into two places:
die(): check the conditions under which we will panic when calling
do_exit and go there directly with the pt_regs that caused the fatal
fault.

die_nmi(): If we receive an NMI lockup while in the kernel use the
pt_regs and go directly to crash_kexec(). We're probably nested up badly
at this point so this might be the only chance to escape with proper
information.

Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:54 -07:00
Zwane Mwaikambo f370513640 [PATCH] i386 CPU hotplug
(The i386 CPU hotplug patch provides infrastructure for some work which Pavel
is doing as well as for ACPI S3 (suspend-to-RAM) work which Li Shaohua
<shaohua.li@intel.com> is doing)

The following provides i386 architecture support for safely unregistering and
registering processors during runtime, updated for the current -mm tree.  In
order to avoid dumping cpu hotplug code into kernel/irq/* i dropped the
cpu_online check in do_IRQ() by modifying fixup_irqs().  The difference being
that on cpu offline, fixup_irqs() is called before we clear the cpu from
cpu_online_map and a long delay in order to ensure that we never have any
queued external interrupts on the APICs.  There are additional changes to s390
and ppc64 to account for this change.

1) Add CONFIG_HOTPLUG_CPU
2) disable local APIC timer on dead cpus.
3) Disable preempt around irq balancing to prevent CPUs going down.
4) Print irq stats for all possible cpus.
5) Debugging check for interrupts on offline cpus.
6) Hacky fixup_irqs() to redirect irqs when cpus go off/online.
7) play_dead() for offline cpus to spin inside.
8) Handle offline cpus set in flush_tlb_others().
9) Grab lock earlier in smp_call_function() to prevent CPUs going down.
10) Implement __cpu_disable() and __cpu_die().
11) Enable local interrupts in cpu_enable() after fixup_irqs()
12) Don't fiddle with NMI on dead cpu, but leave intact on other cpus.
13) Program IRQ affinity whilst cpu is still in cpu_online_map on offline.

Signed-off-by: Zwane Mwaikambo <zwane@linuxpower.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:29 -07:00
Vincent Hanquez 717b594a41 [PATCH] xen: x86: Use more usermode macro
Use the user_mode macro where it's possible.

Signed-off-by: Vincent Hanquez <vincent.hanquez@cl.cam.ac.uk>
Cc: Ian Pratt <m+Ian.Pratt@cl.cam.ac.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:14 -07:00
Vincent Hanquez 1cc6f12e03 [PATCH] xen: x86: Use new macro for debugreg
Make use of the 2 new macro set_debugreg and get_debugreg.

Signed-off-by: Vincent Hanquez <vincent.hanquez@cl.cam.ac.uk>
Cc: Ian Pratt <m+Ian.Pratt@cl.cam.ac.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:13 -07:00
Alexey Dobriyan 129f69465b [PATCH] Remove i386_ksyms.c, almost.
* EXPORT_SYMBOL's moved to other files
* #include <linux/config.h>, <linux/module.h> where needed
* #include's in i386_ksyms.c cleaned up
* After copy-paste, redundant due to Makefiles rules preprocessor directives
  removed:

	#ifdef CONFIG_FOO
	EXPORT_SYMBOL(foo);
	#endif

	obj-$(CONFIG_FOO) += foo.o

* Tiny reformat to fit in 80 columns

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:11 -07:00
Ingo Molnar 39c715b717 [PATCH] smp_processor_id() cleanup
This patch implements a number of smp_processor_id() cleanup ideas that
Arjan van de Ven and I came up with.

The previous __smp_processor_id/_smp_processor_id/smp_processor_id API
spaghetti was hard to follow both on the implementational and on the
usage side.

Some of the complexity arose from picking wrong names, some of the
complexity comes from the fact that not all architectures defined
__smp_processor_id.

In the new code, there are two externally visible symbols:

 - smp_processor_id(): debug variant.

 - raw_smp_processor_id(): nondebug variant. Replaces all existing
   uses of _smp_processor_id() and __smp_processor_id(). Defined
   by every SMP architecture in include/asm-*/smp.h.

There is one new internal symbol, dependent on DEBUG_PREEMPT:

 - debug_smp_processor_id(): internal debug variant, mapped to
                             smp_processor_id().

Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new
lib/smp_processor_id.c file.  All related comments got updated and/or
clarified.

I have build/boot tested the following 8 .config combinations on x86:

 {SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT}

I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT.  (Other
architectures are untested, but should work just fine.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:13 -07:00
Stas Sergeev 48c88211a6 [PATCH] x86: entry.S trap return fixes
do_debug() and do_int3() return void.

This patch fixes the CONFIG_KPROBES variant of do_int3() to return void too
and adjusts entry.S accordingly.

Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:49 -07:00
Linus Torvalds a879cbbb34 x86: make traps on 'iret' be debuggable in user space
This makes a trap on the 'iret' that returns us to user space
cause a nice clean SIGSEGV, instead of just a hard (and silent)
exit.

That way a debugger can actually try to see what happened, and
we also properly notify everybody who might be interested about
us being gone.

This loses the error code, but tells the debugger what happened
with ILL_BADSTK in the siginfo.
2005-04-29 09:38:44 -07:00
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