Commit Graph

4124 Commits

Author SHA1 Message Date
Ingo Molnar
93394a761d Merge branches 'x86/apic', 'x86/cleanups' and 'x86/mm' into x86/core 2009-03-28 22:27:35 +01:00
Ravikiran G Thirumalai
70511134f6 Revert "x86: don't compile vsmp_64 for 32bit"
Partial revert of commit 129d8bc828
titled 'x86: don't compile vsmp_64 for 32bit'

Commit reverted to compile vsmp_64.c if CONFIG_X86_64 is defined,
since is_vsmp_box() needs to indicate that TSCs are not synchronized, and
hence, not a valid time source, even when CONFIG_X86_VSMP is not defined.

Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: shai@scalex86.org
LKML-Reference: <20090324061429.GH7278@localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-25 21:34:28 +01:00
Rusty Russell
e06b1b56f9 x86: Correct behaviour of irq affinity
Impact: get correct smp_affinity as user requested

The effect of setting desc->affinity (ie. from userspace via sysfs) has
varied over time.  In 2.6.27, the 32-bit code anded the value with
cpu_online_map, and both 32 and 64-bit did that anding whenever a cpu
was unplugged.

2.6.29 consolidated this into one routine (and fixed hotplug) but
introduced another variation: anding the affinity with cfg->domain.

We should just set it to what the user said - if possible.

(cpu_mask_to_apicid_and already takes cpu_online_mask into account)

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49C94DDF.2010703@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-25 18:48:29 +01:00
Yinghai Lu
f56e503412 x86: use default_cpu_mask_to_apicid for 64bit
Impact: cleanup

Use online_mask directly on 64bit too.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <49C94DAE.9070300@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-24 22:28:38 +01:00
Yinghai Lu
fa74c90733 x86: fix set_extra_move_desc calling
Impact: fix bug with irq-descriptor moving when logical flat

Rusty observed:

> The effect of setting desc->affinity (ie. from userspace via sysfs) has varied
> over time.  In 2.6.27, the 32-bit code anded the value with cpu_online_map,
> and both 32 and 64-bit did that anding whenever a cpu was unplugged.
>
> 2.6.29 consolidated this into one routine (and fixed hotplug) but introduced
> another variation: anding the affinity with cfg->domain.  Is this right, or
> should we just set it to what the user said?  Or as now, indicate that we're
> restricting it.

Eric pointed out that desc->affinity should be what the user requested,
if it is at all possible to honor the user space request.

This bug got introduced by commit 22f65d31b "x86: Update io_apic.c to use
new cpumask API".

Fix it by moving the masking to before the descriptor moving ...

Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <49C94134.4000408@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-24 22:12:10 +01:00
Ingo Molnar
5c8cd82ed7 Merge branch 'x86/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jaswinder/linux-2.6-tiptop into x86/cleanups 2009-03-24 15:20:51 +01:00
Ingo Molnar
29219683c4 Merge branches 'x86/apic', 'x86/cleanups', 'x86/mm', 'x86/pat', 'x86/setup' and 'x86/signal'; commit 'v2.6.29' into x86/core 2009-03-24 15:19:45 +01:00
Jaswinder Singh Rajput
ba639039d6 x86: e820 fix various signedness issues in setup.c and e820.c
Impact: cleanup

This fixed various signedness issues in setup.c and e820.c:
arch/x86/kernel/setup.c:455:53: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/setup.c:455:53:    expected int *pnr_map
arch/x86/kernel/setup.c:455:53:    got unsigned int extern [toplevel] *<noident>
arch/x86/kernel/setup.c:639:53: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/setup.c:639:53:    expected int *pnr_map
arch/x86/kernel/setup.c:639:53:    got unsigned int extern [toplevel] *<noident>
arch/x86/kernel/setup.c:820:54: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/setup.c:820:54:    expected int *pnr_map
arch/x86/kernel/setup.c:820:54:    got unsigned int extern [toplevel] *<noident>

arch/x86/kernel/e820.c:670:53: warning: incorrect type in argument 3 (different signedness)
arch/x86/kernel/e820.c:670:53:    expected int *pnr_map
arch/x86/kernel/e820.c:670:53:    got unsigned int [toplevel] *<noident>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-23 15:02:05 +05:30
Jaswinder Singh Rajput
a1e38ca5ce x86: apic/io_apic.c define msi_ir_chip and ir_ioapic_chip all the time
move out msi_ir_chip and ir_ioapic_chip from CONFIG_INTR_REMAP shadow

Fix:
 arch/x86/kernel/apic/io_apic.c:1431: warning: ‘msi_ir_chip’ defined but not used

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-23 02:11:25 +05:30
Jaswinder Singh Rajput
474e56b82c x86: irq.c keep CONFIG_X86_LOCAL_APIC interrupts together
Impact: cleanup

keep CONFIG_X86_LOCAL_APIC interrupts together to avoid extra ifdef

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-23 02:08:34 +05:30
Jaswinder Singh Rajput
ce2d8bfd44 x86: irq.c use same path for show_interrupts
Impact: cleanup

SMP and !SMP will use same path for show_interrupts

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-23 02:08:00 +05:30
Jaswinder Singh Rajput
f2362e6f1b x86: cpu/cpu.h cleanup
Impact: cleanup

 - Fix various style issues

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-23 02:06:51 +05:30
Dmitri Vorobiev
1cc185211a x86: Fix a couple of sparse warnings in arch/x86/kernel/apic/io_apic.c
Impact: cleanup

This patch fixes the following sparse warnings:

 arch/x86/kernel/apic/io_apic.c:3602:17: warning: symbol 'hpet_msi_type'
 was not declared. Should it be static?

 arch/x86/kernel/apic/io_apic.c:3467:30: warning: Using plain integer as
 NULL pointer

Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.com>
LKML-Reference: <1237741871-5827-2-git-send-email-dmitri.vorobiev@movial.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-22 18:15:14 +01:00
Ingo Molnar
648340dff0 Merge branch 'x86/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jaswinder/linux-2.6-tip into x86/cleanups 2009-03-21 17:37:35 +01:00
Jaswinder Singh Rajput
1894e36754 x86: pci-nommu.c cleanup
Impact: cleanup

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 17:01:25 +05:30
Jaswinder Singh Rajput
d53a444460 x86: io_delay.c cleanup
Impact: cleanup

 - fix header file issues

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 16:57:04 +05:30
Jaswinder Singh Rajput
8383d821e7 x86: rtc.c cleanup
Impact: cleanup

 - fix various style problems
  - fix header file issues

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 16:56:37 +05:30
Jaswinder Singh Rajput
c8344bc218 x86: i8253 cleanup
Impact: cleanup

 - fix various style problems
  - fix header file issues

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 16:56:10 +05:30
Jaswinder Singh Rajput
390cd85c8a x86: kdebugfs.c cleanup
Impact: cleanup

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 16:55:45 +05:30
Jaswinder Singh Rajput
271eb5c588 x86: topology.c cleanup
Impact: cleanup

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 16:55:24 +05:30
Jaswinder Singh Rajput
0b3ba0c3cc x86: mpparse.c introduce check_physptr helper function
To reduce the size of the oversized function __get_smp_config()

There should be no impact to functionality.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 14:15:43 +05:30
Jaswinder Singh Rajput
5a5737eac2 x86: mpparse.c introduce smp_dump_mptable helper function
smp_read_mpc() and replace_intsrc_all() can use same smp_dump_mptable()

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-03-21 14:15:11 +05:30
Bartlomiej Zolnierkiewicz
04c93ce499 x86: fix IO APIC resource allocation error message
Impact: fix incorrect error message

- IO APIC resource allocation error message contains one too many "be".

- Print the error message iff there are IO APICs in the system.

I've seen this error message for some time on my x86-32 laptop...

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Alan Bartlett <ajb.stxsl@googlemail.com>
LKML-Reference: <200903202100.30789.bzolnier@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-20 21:02:55 +01:00
Hiroshi Shimamoto
14fc9fbc70 x86: signal: check signal stack overflow properly
Impact: cleanup

Check alternate signal stack overflow with proper stack pointer.
The stack pointer of the next signal frame is different if that
task has i387 state.

On x86_64, redzone would be included.

No need to check SA_ONSTACK if we're already using alternate signal stack.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Roland McGrath <roland@redhat.com>
LKML-Reference: <49C2874D.3080002@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-20 19:01:31 +01:00
Ingo Molnar
7f00a2495b Merge branches 'x86/cleanups', 'x86/mm', 'x86/setup' and 'linus' into x86/core 2009-03-20 10:34:22 +01:00
Jeremy Fitzhardinge
71ff49d71b x86: with the last user gone, remove set_pte_present
Impact: cleanup

set_pte_present() is no longer used, directly or indirectly,
so remove it.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
LKML-Reference: <1237406613-2929-2-git-send-email-jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-19 14:04:19 +01:00
Ingo Molnar
c58603e81b x86: mpparse: clean up code by introducing a few helper functions, fix
Impact: fix boot crash

This fixes commit a683027856.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1237403503.22438.21.camel@ht.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-19 08:52:13 +01:00
Jaswinder Singh Rajput
a683027856 x86: mpparse: clean up code by introducing a few helper functions
Impact: cleanup

Refactor the MP-table parsing code via the introduction of the
following helper functions:

  skip_entry()
  smp_reserve_bootmem()
  check_irq_src()
  check_slot()

To simplify the code flow and to reduce the size of the
following oversized functions: smp_read_mpc(), smp_scan_config().

There should be no impact to functionality.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 17:15:05 +01:00
Jaswinder Singh Rajput
cde5edbda8 x86: kprobes.c fix compilation warning
arch/x86/kernel/kprobes.c:196: warning: passing argument 1 of ‘search_exception_tables’ makes integer from pointer without a cast

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference:<49BED952.2050809@redhat.com>
LKML-Reference: <1237378065.13488.2.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 13:21:01 +01:00
Ingo Molnar
705bb9dc72 Merge branches 'x86/cleanups', 'x86/cpu', 'x86/debug', 'x86/mce2', 'x86/mm', 'x86/mtrr', 'x86/setup', 'x86/setup-memory', 'x86/urgent', 'x86/uv', 'x86/x2apic' and 'linus' into x86/core
Conflicts:
	arch/parisc/kernel/irq.c
2009-03-18 13:19:49 +01:00
Jaswinder Singh Rajput
4e16c88875 x86: cpu/mttr/cleanup.c fix compilation warning
arch/x86/kernel/cpu/mtrr/cleanup.c:197: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long unsigned int’

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1237378015.13488.1.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 13:14:31 +01:00
Rusty Russell
2c74d66624 x86, uv: fix cpumask iterator in uv_bau_init()
Impact: fix boot crash on UV systems

Commit 76ba0ecda0 "cpumask: use
cpumask_var_t in uv_flush_tlb_others" used cur_cpu as an iterator;
it was supposed to be zero for the code below it.

Reported-by: Cliff Wickman <cpw@sgi.com>
Original-From: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Mike Travis <travis@sgi.com>
Cc: steiner@sgi.com
Cc: <stable@kernel.org>
LKML-Reference: <200903180822.31196.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 09:47:54 +01:00
Suresh Siddha
ce4e240c27 x86: add x2apic_wrmsr_fence() to x2apic flush tlb paths
Impact: optimize APIC IPI related barriers

Uncached MMIO accesses for xapic are inherently serializing and hence
we don't need explicit barriers for xapic IPI paths.

x2apic MSR writes/reads don't have serializing semantics and hence need
a serializing instruction or mfence, to make all the previous memory
stores globally visisble before the x2apic msr write for IPI.

Add x2apic_wrmsr_fence() in flush tlb path to x2apic specific paths.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "steiner@sgi.com" <steiner@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
LKML-Reference: <1237313814.27006.203.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 09:36:14 +01:00
Andrew Morton
a6b6a14e0c x86: use smp_call_function_single() in arch/x86/kernel/cpu/mcheck/mce_amd_64.c
Attempting to rid us of the problematic work_on_cpu().  Just use
smp_call_function_single() here.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <20090318042217.EF3F1DDF39@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 07:03:12 +01:00
Suresh Siddha
68a8ca593f x86: fix broken irq migration logic while cleaning up multiple vectors
Impact: fix spurious IRQs

During irq migration, we send a low priority interrupt to the previous
irq destination. This happens in non interrupt-remapping case after interrupt
starts arriving at new destination and in interrupt-remapping case after
modifying and flushing the interrupt-remapping table entry caches.

This low priority irq cleanup handler can cleanup multiple vectors, as
multiple irq's can be migrated at almost the same time. While
there will be multiple invocations of irq cleanup handler (one cleanup
IPI for each irq migration), first invocation of the cleanup handler
can potentially cleanup more than one vector (as the first invocation can
see the requests for more than vector cleanup). When we cleanup multiple
vectors during the first invocation of the smp_irq_move_cleanup_interrupt(),
other vectors that are to be cleanedup can still be pending in the local
cpu's IRR (as smp_irq_move_cleanup_interrupt() runs with interrupts disabled).

When we are ready to unhook a vector corresponding to an irq, check if that
vector is registered in the local cpu's IRR. If so skip that cleanup and
do a self IPI with the cleanup vector, so that we give a chance to
service the pending vector interrupt and then cleanup that vector
allocation once we execute the lowest priority handler.

This fixes spurious interrupts seen when migrating multiple vectors
at the same time.

[ This is apparently possible even on conventional xapic, although to
  the best of our knowledge it has never been seen.  The stable
  maintainers may wish to consider this one for -stable. ]

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: stable@kernel.org
2009-03-17 16:49:30 -07:00
Suresh Siddha
05c3dc2c4b x86, ioapic: Fix non atomic allocation with interrupts disabled
Impact: fix possible race

save_mask_IO_APIC_setup() was using non atomic memory allocation while getting
called with interrupts disabled. Fix this by splitting this into two different
function. Allocation part save_IO_APIC_setup() now happens before
disabling interrupts.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:45:29 -07:00
Suresh Siddha
29b61be65a x86, x2apic: cleanup ifdef CONFIG_INTR_REMAP in io_apic code
Impact: cleanup

Clean up #ifdefs and replace them with helper functions.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:45:07 -07:00
Suresh Siddha
0280f7c416 x86, x2apic: cleanup the IO-APIC level migration with interrupt-remapping
Impact: simplification

In the current code, for level triggered migration, we need to modify the
io-apic RTE with the update vector information, along with modifying interrupt
remapping table entry(IRTE) with vector and destination. This is to ensure that
remote IRR bit inthe IOAPIC RTE gets cleared when the cpu does EOI.

With this patch, for level triggered, we eliminate the io-apic RTE modification
(with the updated vector information), by using a virtual vector (io-apic pin
number).  Real vector that is used for interrupting cpu will be coming from
the interrupt-remapping table entry. Trigger mode in the IRTE will always be
edge, and the actual level or edge trigger will be setup in the IO-APIC RTE.
So a level triggered interrupt will appear as an edge to the local apic
cpu but still as level to the IO-APIC.

With this change, level irq migration can be done by simply modifying
the interrupt-remapping table entry with out changing the io-apic RTE.
And as the interrupt appears as edge at the cpu, in addition to do the
local apic EOI, we need to do IO-APIC directed EOI to clear the remote
IRR bit in  the IO-APIC RTE.

This simplies the irq migration in the presence of interrupt-remapping.

Idea-by: Rajesh Sankaran <rajesh.sankaran@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:44:27 -07:00
Suresh Siddha
cf6567fe40 x86, x2apic: fix clear_local_APIC() in the presence of x2apic
Impact: cleanup, paranoia

We were not clearing the local APIC in clear_local_APIC() in the
presence of x2apic. Fix it.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:43:51 -07:00
Suresh Siddha
7c6d9f9785 x86, x2apic: use virtual wire A mode in disable_IO_APIC() with interrupt-remapping
Impact: make kexec work with x2apic

disable_IO_APIC() gets called during crashdump aswell, which configures the
IO-APIC/LAPIC so that legacy interrupts can be delivered for the kexec'd kernel.

In the presence of interrupt-remapping, we need to change the
interrupt-remapping configuration aswell as modifying IO-APIC for virtual wire
B mode.

To keep things simple during the crash, use virtual wire A mode
(for which we don't need to touch io-apic and interrupt-remapping tables).

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:42:28 -07:00
Suresh Siddha
9d783ba042 x86, x2apic: enable fault handling for intr-remapping
Impact: interface augmentation (not yet used)

Enable fault handling flow for intr-remapping aswell. Fault handling
code now shared by both dma-remapping and intr-remapping.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:38:59 -07:00
H. Peter Anvin
0a699af8e6 x86-32: move _end to a dummy section
Impact: build fix with CONFIG_RELOCATABLE

Move _end into a dummy section, so that relocs.c will know it is a
relocatable symbol.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2009-03-17 14:16:02 -07:00
Jeremy Fitzhardinge
704439ddf9 x86/brk: put the brk reservations in their own section
Impact: disambiguate real .bss variables from .brk storage

Add a .brk section after the .bss section.  This has no effect
on the final vmlinux, but it more clearly distinguishes the space
taken by actual .bss symbols, and the variable space reserved
by .brk users.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-17 12:58:15 -07:00
H. Peter Anvin
60ac982139 x86-32: tighten the bound on additional memory to map
Impact: Tighten bound to avoid masking errors

The definition of MAPPING_BEYOND_END was excessive; this has a nasty
tendency to mask bugs.  We have learned over time that this kind of
bug hiding can cause some very strange errors.  Therefore, tighten the
bound to only need to map the actual kernel area.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
2009-03-17 11:52:10 -07:00
Jeremy Fitzhardinge
b8a22a6273 x86-32: remove ALLOCATOR_SLOP from head_32.S
Impact: cleanup

ALLOCATOR_SLOP is a vestigial remain from when we used the
bootmem allocator to allocate the kernel's linear memory mapping.
Now we directly reserve pages from the e820 mapping, and no
longer require secondary structures to keep track of allocated
pages.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 11:46:01 -07:00
Jeremy Fitzhardinge
c090f532db x86-32: make sure we map enough to fit linear map pagetables
Impact: crash fix

head_32.S needs to map the kernel itself, and enough space so
that mm/init.c can allocate space from the e820 allocator
for the linear map of low memory.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 11:42:05 -07:00
Masami Hiramatsu
30390880de prevent boosting kprobes on exception address
Don't boost at the addresses which are listed on exception tables,
because major page fault will occur on those addresses.  In that case,
kprobes can not ensure that when instruction buffer can be freed since
some processes will sleep on the buffer.

kprobes-ia64 already has same check.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 09:11:48 -07:00
Linus Torvalds
9e8912e04e Fast TSC calibration: calculate proper frequency error bounds
In order for ntpd to correctly synchronize the clocks, the frequency of
the system clock must not be off by more than 500 ppm (or, put another
way, 1:2000), or ntpd will end up giving up on trying to synchronize
properly, and ends up reseting the clock in jumps instead.

The fast TSC PIT calibration sometimes failed this test - it was
assuming that the PIT reads always took about one microsecond each (2us
for the two reads to get a 16-bit timer), and that calibrating TSC to
the PIT over 15ms should thus be sufficient to get much closer than
500ppm (max 2us error on both sides giving 4us over 15ms: a 270 ppm
error value).

However, that assumption does not always hold: apparently some hardware
is either very much slower at reading the PIT registers, or there was
other noise causing at least one machine to get 700+ ppm errors.

So instead of using a fixed 15ms timing loop, this changes the fast PIT
calibration to read the TSC delta over the individual PIT timer reads,
and use the result to calculate the error bars on the PIT read timing
properly.  We then successfully calibrate the TSC only if the maximum
error bars fall below 500ppm.

In the process, we also relax the timing to allow up to 25ms for the
calibration, although it can happen much faster depending on hardware.

Reported-and-tested-by: Jesper Krogh <jesper@krogh.cc>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 08:13:17 -07:00
Linus Torvalds
a6a80e1d8c Fix potential fast PIT TSC calibration startup glitch
During bootup, when we reprogram the PIT (programmable interval timer)
to start counting down from 0xffff in order to use it for the fast TSC
calibration, we should also make sure to delay a bit afterwards to allow
the PIT hardware to actually start counting with the new value.

That will happens at the next CLK pulse (1.193182 MHz), so the easiest
way to do that is to just wait at least one microsecond after
programming the new PIT counter value.  We do that by just reading the
counter value back once - which will take about 2us on PC hardware.

Reported-and-tested-by: john stultz <johnstul@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 07:58:26 -07:00
Yinghai Lu
f0348c438c x86: MTRR workaround for system with stange var MTRRs
Impact: don't trim e820 according to wrong mtrr

Ozan reports that his server emits strange warning.
it turns out the BIOS sets the MTRRs incorrectly.

Ignore those strange ranges, and don't trim e820,
just emit one warning about BIOS

Reported-by: Ozan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BEE1E7.7020706@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-17 10:47:47 +01:00