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: NOzan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BEE1E7.7020706@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: print out fewer lines

 1. print continuous range with same type together
 2. change _INFO to _DEBUG
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <49BACB61.8000302@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix debug warning

Jaswinder noticed that there is a warning about smp_processor_id()
in get_mtrr().

Fix it by wrapping the printout into a get/put_cpu() pair.
Reported-by: NJaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49BAB7FF.4030107@kernel.org>
[ changed to get/put_cpu(), cleaned up surrounding code a it. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: bug fix + BIOS workaround

BIOS is expected to clear the SYSCFG[MtrrFixDramModEn] on AMD CPUs
after fixed MTRRs are configured.

Some BIOSes do not clear SYSCFG[MtrrFixDramModEn] on BP (and on APs).

This can lead to obfuscation in Linux when this bit is not cleared on
BP but cleared on APs. A consequence of this is that the saved
fixed-MTRR state (from BP) differs from the fixed-MTRRs of APs --
because RdDram/WrDram bits are read as zero when
SYSCFG[MtrrFixDramModEn] is cleared -- and Linux tries to sync
fixed-MTRR state from BP to AP. This implies that Linux sets
SYSCFG[MtrrFixDramEn] and activates those bits.

More important is that (some) systems change these bits in SMM when
ACPI is enabled. Hence it is racy if Linux modifies RdMem/WrMem bits,
too.

(1) The patch modifies an old fix from Bernhard Kaindl to get
    suspend/resume working on some Acer Laptops. Bernhard's patch
    tried to sync RdMem/WrMem bits of fixed MTRR registers and that
    helped on those old Laptops. (Don't ask me why -- can't test it
    myself). But this old problem was not the motivation for the
    patch. (See http://lkml.org/lkml/2007/4/3/110)

(2) The more important effect is to fix issues on some more current systems.

    On those systems Linux panics or just freezes, see

    http://bugzilla.kernel.org/show_bug.cgi?id=11541
    (and also duplicates of this bug:
    http://bugzilla.kernel.org/show_bug.cgi?id=11737
    http://bugzilla.kernel.org/show_bug.cgi?id=11714)

    The affected systems boot only using acpi=ht, acpi=off or
    when the kernel is built with CONFIG_MTRR=n.

    The acpi options prevent full enablement of ACPI.  Obviously when
    ACPI is enabled the BIOS/SMM modfies RdMem/WrMem bits.  When
    CONFIG_MTRR=y Linux also accesses and modifies those bits when it
    needs to sync fixed-MTRRs across cores (Bernhard's fix, see (1)).
    How do you synchronize that? You can't. As a consequence Linux
    shouldn't touch those bits at all (Rationale are AMD's BKDGs which
    recommend to clear the bit that makes RdMem/WrMem accessible).
    This is the purpose of this patch. And (so far) this suffices to
    fix (1) and (2).

I suggest not to touch RdDram/WrDram bits of fixed-MTRRs and
SYSCFG[MtrrFixDramEn] and to clear SYSCFG[MtrrFixDramModEn] as
suggested by AMD K8, and AMD family 10h/11h BKDGs.
BIOS is expected to do this anyway. This should avoid that
Linux and SMM tread on each other's toes ...
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
Cc: trenn@suse.de
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090312163937.GH20716@alberich.amd.com>
Cc: <stable@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

mtrr main.c is too big, seperate mtrr cleanup and mtrr e820 trim
code to another file.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B87C7B.80809@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: print more debug info

Keep it consistent with autodetect version.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B87C0A.4010105@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: improve MTRR debugging messages

There's still inefficiencies suspected with the MTRR sanitizing
code, so make sure we get all the info we need from a dmesg.

- Remove unneeded mtrr_show

 (It will only printout one time by first cpu, so it is no big deal.)

- Also print out directly from get_mtrr, because it doesn't update mtrr_state.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B9BA5A.40108@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge branches 'x86/asm', 'x86/debug', 'x86/mm', 'x86/setup', 'x86/urgent' and 'linus' into x86/core

This message was being incorrectly emitted when using gdb,
so compile it out by default for now; there will be a
better fix in v2.6.30.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NStuart Bennett <stuart@freedesktop.org>
Acked-by: NPekka Paalanen <pq@iki.fi>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm: fix EDID parser problem with positive/negative hsync/vsync

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  radeonfb/aty128fb: Disable broken early resume hook for PowerBooks
  hvc_console: Remove tty->low_latency on pseries backends
  powerpc: fix linkstation and storcenter compilation breakage
  powerpc/4xx: Enable SERIAL_OF support by default for Virtex platforms

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
  drm/i915: fix 945 fence register writes for fence 8 and above.
  drm/i915: Protect active fences on i915
  drm/i915: Check to see if we've pinned all available fences
  drm/i915: Check fence status on every pin.
  drm/i915: First recheck for an empty fence register.
  drm/i915: Fix bad \n in MTRR failure notice.
  drm/i915: Don't restore palettes through VGA registers.
  i915: add newline to i915_gem_object_pin failure msg
  drm: Return EINVAL on duplicate objects in execbuffer object list

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: work around Fedora-11 x86-32 kernel failures on Intel Atom CPUs

On swapon() path, it has already i_mutex. So, this uses i_alloc_sem
instead of it.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reported-by: NLaurent GUERBY <laurent@guerby.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The last 8 fence registers sit at a different offset, so when we went to set
fence number 8 in the lower offset, we instead set PGETBL_CTL, and the GPU
got all sorts of angry at us.

fd.o bug #20567.  Easily reproducible by running glxgears and killing it about
6 times.
Signed-off-by: NEric Anholt <eric@anholt.net>

Impact: obsolete feature removal

The zImage kernel format has been functionally unused for a very long
time.  It is just barely possible to build a modern kernel that still
fits within the zImage size limit, but it is highly unlikely that
anyone ever uses it.  Furthermore, although it is still supported by
most bootloaders, it has been at best poorly tested (or not tested at
all); some bootloaders are even known to not support zImage at all and
not having even noticed.

Also remove some really obsolete constants that no longer have any
meaning.

LKML-Reference: <49B703D4.1000008@zytor.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The i915 also uses the fence registers for GPU access to tiled buffers so
we cannot reallocate one whilst it is on the active list. By performing a
LRU scan of the fenced buffers we also avoid waiting the possibility of
waiting on a pinned, or otherwise unusable, buffer.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>

Impact: work around boot crash

Work around Intel Atom erratum AAH41 (probabilistically) - it's triggering
in the field.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Tested-by: NKyle McMartin <kyle@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

It may be useful for kmap_atomic_pfn() and iomap_atomic_prot_pfn()
to check invalid kmap usage as well as kmap_atomic.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <20090311143449.GB22244@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kmap_atomic_pfn() and iomap_atomic_prot_pfn() are almost same
except pgprot. This patch removes the code duplication for these
two functions.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <20090311143317.GA22244@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix kpf_copy_bit(src,dst) to be kpf_copy_bit(dst,src) to match the
actual call patterns, e.g. kpf_copy_bit(kflags, KPF_LOCKED, PG_locked).

This misplacement of src/dst only affected reporting of PG_writeback,
PG_reclaim and PG_buddy. For others kflags==uflags so not affected.
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

move store_ldt outside the CONFIG_PARAVIRT section and
also clean up the code a bit.
Signed-off-by: NJaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

1) .p2align 4 and .align 16 are the same meaning
   (until a.out format for i386 is used which is
    not our case for CONFIG_X86_ALIGNMENT_16 anyway)

2) having 15 as max allowed bytes to be skipped
   does not make sense on modulo 16
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <20090309171951.GE9945@localhost>
[ small cleanup, use __stringify(), etc. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

Convert the last remaining users.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Impact: saving power _very_ little

round_jiffies() round up absolute jiffies to full second.
round_jiffies_relative() round up relative jiffies to full second.

The "t->expires" is absolute jiffies. Then, round_jiffies() should be
used instead round_jiffies_relative().
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

We need to check and report if there are no available fences - or else we
spin endlessly waiting for a buffer to magically unpin itself.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>

As we may steal the fence register of an unpinned buffer for another,
every time we repin the buffer we need to recheck whether it needs to be
allocated a fence.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>

If we wait upon a request and successfully unbind a buffer occupying a
fence register, then that slot will be freed and cause a NULL derefrence
upon rescanning.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>

Comparing the layouts of struct detail_pixel_timing with
x.org's struct detailed_timings and how those are handled,
it appears that the hsync_positive and vsync_positive
fields are backwards.

This patch fixes https://bugs.freedesktop.org/show_bug.cgi?id=20019
for me. It was tested on 2 monitors, LG FLATRON L225WS 22" and
a YAKUMO 17" for which more details are unknown.
Signed-off-by: NPantelis Koukousoulas <pktoss@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Impact: New major feature

This patch add kexec jump support for x86_64. More information about
kexec jump can be found in corresponding x86_32 support patch.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Fix corner case that cannot yet occur

image->start may be outside of 0 ~ max_pfn, for example when jumping
back to original kernel from kexeced kenrel. This patch add identity
map for pages at image->start.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: Cleanup

Fix some coding style issue for kexec x86.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

radeonfb and aty128fb have a special hook called by the PowerMac platform
code very very early on resume from sleep to bring the screen back. This
is useful for debugging wakup problems, but unfortunately, this also became
a source of problems of its own.

The hook is called extremely early, with interrupts still off, and the code
path involved with that code nowadays rely on things like taking mutexes,
GFP_KERNEL allocations, etc...

In addition, the driver now relies on the PCI core to restore the standard
config space before calling resume which doesn't happen with this early
code path.

I'm keeping the code in but commented out along with a fixup call to
pci_restore_state(). The reason is that I still want to make it easy to
re-enable temporarily to track wake up problems, and it's possible that
I can revive it at some stage if we make sleeping things save to call
in early resume using a system state.

In the meantime, this should fix several reported regressions.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The hvcs and hvsi backends both set tty->low_latency to one, along
with more or less scary comments regarding bugs or races that would
happen if not doing so.

However, they also both call tty_flip_buffer_push() in conexts where
it's illegal to do so since some recent tty changes (or at least it
may have been illegal always but it nows blows) when low_latency is
set (ie, hard interrupt or with spinlock held and irqs disabled).

This removes the setting for now to get them back to working condition,
we'll have to address the races described in the comments separately
if they are still an issue (some of this might have been fixed already).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Prevent the kernel from being crashed by a divide-by-zero operation when
supplied an incorrectly filled 'struct fb_var_screeninfo' from userland.

Previously i810_main.c:1005 (i810_check_params) was using the global
'yres' symbol previously defined at i810_main.c:145 as a module parameter
value holder (i810_main.c:2174).  If i810fb is compiled-in or if this
param doesn't get a default value, this direct usage leads to a
divide-by-zero at i810_main.c:1005 (i810_check_params).  The patch simply
replace the 'yres' global, perhaps undefined symbol usage by a given
parameter structure lookup.

This problem occurs with directfb, mplayer -vo fbdev, SDL library.
It was also reported ( but non solved ) at:

	http://mail.directfb.org/pipermail/directfb-dev/2008-March/004050.htmlSigned-off-by: NSamuel CUELLA <samuel.cuella@supinfo.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There isn't any mcfqspi.h in the tree, and without it everything inside the
#ifdef CONFIG_SPI is uncompilable.
Signed-off-by: NSteven King <sfking@fdwdc.com>
Acked-by: NGreg Ungerer <gerg@snapgear.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NSteven King <sfking@fdwdc.com>
Acked-by: NGreg Ungerer <gerg@snapgear.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Update the RCU documentation to call out the need for callers of
primitives like call_rcu() and synchronize_rcu() to prevent subsequent RCU
readers from hazard.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>