lguest didn't initialize the kernel stack the way a real i386 kernel
does, and ended up triggering a corner-case in the stack frame checking
that doesn't happen on naive i386, and that the stack dumping didn't
handle quite right.

This makes the frame handling more correct, and tries to clarify the
code at the same time so that it's a bit more obvious what is going on.

Thanks to Rusty Russell for debugging the lguest failure-

Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The VESA BIOS is specified to be register-clean.  However, we have now
found at least one system which violates that.  Thus, be as paranoid
about VESA calls as about everything else.

Huge thanks to Will Simoneau for reporting, diagnosing, and testing
this out on Dell Inspiron 5150.

Cc: Will Simoneau <simoneau@ele.uri.edu>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

For hugepage mappings, the file offset, like the address and size, needs to
be aligned to the size of a hugepage.

In commit 68589bc3, the check for this was
moved into prepare_hugepage_range() along with the address and size checks.
 But since BenH's rework of the get_unmapped_area() paths leading up to
commit 4b1d8929, prepare_hugepage_range()
is only called for MAP_FIXED mappings, not for other mappings.  This means
we're no longer ever checking for an aligned offset - I've confirmed that
mmap() will (apparently) succeed with a misaligned offset on both powerpc
and i386 at least.

This patch restores the check, removing it from prepare_hugepage_range()
and putting it back into hugetlbfs_file_mmap().  I'm putting it there,
rather than in the get_unmapped_area() path so it only needs to go in one
place, than separately in the half-dozen or so arch-specific
implementations of hugetlb_get_unmapped_area().
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Passing a u8 into a register doesn't mean gcc will zero-extend it.
Also, don't depend on thhe register not to change.

Per bug report from Saul Tamari.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

asm() statements need to be volatile when:

a. They have side effects (other than value returned).
b. When the value returned can vary over time.
c. When they have ordering constraints that cannot be expressed to gcc.

In particular, the keyboard and timer reads were violating constraint (b),
which resulted in the keyboard/timeout poll getting
loop-invariant-removed when compiling with gcc 4.2.0.

Thanks to an anonymous bug reporter for pointing this out.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

construct a more or less wall-clock time out of sched_clock(), by
using ACPI-idle's existing knowledge about how much time we spent
idling. This allows the rq clock to work around TSC-stops-in-C2,
TSC-gets-corrupted-in-C3 type of problems.

( Besides the scheduler's statistics this also benefits blktrace and
  printk-timestamps as well. )

Furthermore, the precise before-C2/C3-sleep and after-C2/C3-wakeup
callbacks allow the scheduler to get out the most of the period where
the CPU has a reliable TSC. This results in slightly more precise
task statistics.

the ACPI bits were acked by Len.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NLen Brown <len.brown@intel.com>

Xen i386 xen-head.S fix sections mixup

xen-head.S does not come back to the data section, leaving the text section
as current section. It causes problems with a slightly enhanced DEBUG_RODATA
that supports CONFIG_HOTPLUG and bringing a CPU up after the text has been
marked read-only: reference to early_gdt_descr causes a page fault.

Updates:

- It should be using pushsection/popsection.
- Actually, the push/popsections around the ELFNOTEs are redundant; ELFNOTE()
  does its own push/popsection to put things into the appropriate .note* section
  anyway.
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Touching vmalloc memory in the middle of a lazy mode update can generate
a kernel PDE update, which must be flushed immediately.  The fix is to
leave lazy mode when doing a vmalloc sync.
Signed-off-by: NZachary Amsden <zach@vmware.com>
Acked-by: NJeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I did some testing and found quite a lot of problems (doesn't
boot at all on non NUMA and misassigns cores on Opteron systems).

Mark it as experimental and warn against its use for now.

It's still default y for SUMMIT/NUMAQ because it'll presumably
work on these systems.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In MPS mode, "nosmp" and "maxcpus=0" boot a UP kernel with IOAPIC disabled.
However, in ACPI mode, these parameters didn't completely disable
the IO APIC initialization code and boot failed.

init/main.c:
	Disable the IO_APIC if "nosmp" or "maxcpus=0"
	undefine disable_ioapic_setup() when it doesn't apply.

i386:
	delete ioapic_setup(), it was a duplicate of parse_noapic()
	delete undefinition of disable_ioapic_setup()

x86_64:
	rename disable_ioapic_setup() to parse_noapic() to match i386
	define disable_ioapic_setup() in header to match i386

http://bugzilla.kernel.org/show_bug.cgi?id=1641Acked-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

With commit ab144f5e the patching code
now collects the complete new instruction stream into a temp buffer
before finally patching in the new insns.  In some cases the paravirt
patchers will choose to leave the patch site unpatched (length mismatch,
clobbers mismatch, etc).

This causes the new patching code to copy an uninitialized temp buffer,
i.e.  garbage, to the callsite.  Simply make sure to always initialize
the buffer with the original instruction stream.  A better fix is to
audit all the patchers and return proper length so that apply_paravirt()
can skip copies when we leave the patch site untouched.
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Very old 64bit binutils have .cfi_startproc/endproc, but
no .cfi_rel_offset. Check for .cfi_rel_offset too.

Cc: Jan Beulich <jbeulich@novell.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixed wrong expression which enabled watchdogs even if nmi_watchdog kernel
parameter wasn't set. This regression got slightly introduced with commit
b7471c6d.

Introduced NMI_DISABLED (-1) which allows to switch the value of NMI_DEFAULT
without breaking the APIC NMI watchdog code (again).

Fixes:
   https://bugzilla.novell.com/show_bug.cgi?id=298084
   http://bugzilla.kernel.org/show_bug.cgi?id=7839
And likely some more nmi_watchdog=0 related issues.
Signed-off-by: NDaniel Gollub <dgollub@suse.de>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (edited MACINTOSH_DRIVERS per Geert Uytterhoeven's remark)
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When filling in the MBR signature array, the setup code failed to advance
boot_params.edd_mbr_sig_buf_entries, which resulted in the valid data
being ignored.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

At least one machine has been identified in the field which advertises
EDD for all drives but locks up if one attempts an extended read from
a non-primary drive.

The MBR is always at CHS 0-0-1, so there is no reason to use an
extended read, other than the possibility that the BIOS cannot handle
it.

Although this might break as many machines as it fixes (a small number
either way), the current state is a regression but the reverse is not.
Therefore revert to the previous state of not using extended read.

Quite probably the Right Thing to do is to read using plain (CHS) read
and extended read on failure, but that change would definitely have to
go through -mm first.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The current display page is an 8-bit number, even though struct
screen_info gives it a 16-bit number.  The number is returned in %bh,
so it needs to be >> 8 before storing.

Special thanks to Jeff Chua for detailed bug reporting.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Level type interrupts do not need to be resent.  It was also found that
some chipsets get confused in case of the resend.

Mark the ioapic level type interrupts as such to avoid the resend
functionality in the generic irq code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 3320ad99 broke mmio config space
accesses totally on i386 - it dropped the "reg" offset to the address.

Cc: dean gaudet <dean@arctic.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new percpu code has apparently broken the doublefault handler
when CONFIG_DEBUG_SPINLOCK is set. Doublefault is handled by
a hardware task, making the check

        SPIN_BUG_ON(lock->owner == current, lock, "recursion");

fault because it uses the FS register to access the percpu data
for current, and that register is zero in the new TSS. (The trace
I saw was on 2.6.20 where it was GS, but it looks like this will
still happen with FS on 2.6.22.)

Initializing FS in the doublefault_tss should fix it.

AK: Also fix broken ptr_ok() and turn printks into KERN_EMERG
AK: And add a PANIC prefix to make clear the system will hang
AK: (e.g. x86-64 will recover)
Signed-off-by: NChuck Ebbert <cebbert@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix

WARNING: vmlinux.o(.text+0x183): Section mismatch: reference to .init.text:start_kernel (between 'is386' and 'check_x87')
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The Averatec 2370 and some other Turion laptop BIOS seems to program the
ENABLE_C1E MSR inconsistently between cores. This confuses the lapic
use heuristics because when C1E is enabled anywhere it seems to affect
the complete chip.

Use a global flag instead of a per cpu flag to handle this.
If any CPU has C1E enabled disabled lapic use.

Thanks to Cal Peake for debugging.

Cc: tglx@linutronix.de
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It's CONFIG_X86_MCE, not CONFIG_MCE.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 19d36ccd "x86: Fix alternatives
and kprobes to remap write-protected kernel text" uses code which is
being patched for patching.

In particular, paravirt_ops does patching in two stages: first it
calls paravirt_ops.patch, then it fills any remaining instructions
with nop_out().  nop_out calls text_poke() which calls
lookup_address() which calls pgd_val() (aka paravirt_ops.pgd_val):
that call site is one of the places we patch.

If we always do patching as one single call to text_poke(), we only
need make sure we're not patching the memcpy in text_poke itself.
This means the prototype to paravirt_ops.patch needs to change, to
marshal the new code into a buffer rather than patching in place as it
does now.  It also means all patching goes through text_poke(), which
is known to be safe (apply_alternatives is also changed to make a
single patch).

AK: fix compilation on x86-64 (bad rusty!)
AK: fix boot on x86-64 (sigh)
AK: merged with other patches
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It turns out CLFLUSH support is still not complete; we
flush the wrong pages.  Again disable it for the release.
Noticed by Jan Beulich who then also noticed a stupid typo later.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some broken devices have been discovered to require %al/%ax/%eax registers
for MMIO config space accesses.  Modify mmconfig.c to use these registers
explicitly (rather than modify the global readb/writeb/etc inlines).

AK: also changed i386 to always use eax
AK: moved change to extended space probing to different patch
AK: reworked with inlines according to Linus' requirements.
AK: improve comments.
Signed-off-by: Ndean gaudet <dean@arctic.org>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch finishes the i386 and x86-64 ->sysdata conversion and hopefully
also fixes Riku's and Andy's observed bugs.  It is based on Yinghai Lu's
and Andy Whitcroft's patches (thanks!) with some changes:

- introduce pci_scan_bus_with_sysdata() and use it instead of
  pci_scan_bus() where appropriate. pci_scan_bus_with_sysdata() will
  allocate the sysdata structure and then call pci_scan_bus().
- always allocate pci_sysdata dynamically. The whole point of this
  sysdata work is to make it easy to do root-bus specific things
  (e.g., support PCI domains and IOMMU's). I dislike using a default
  struct pci_sysdata in some places and a dynamically allocated
  pci_sysdata elsewhere - the potential for someone indavertantly
  changing the default structure is too high.
- this patch only makes the minimal changes necessary, i.e., the NUMA node is
  always initialized to -1. Patches to do the right thing with regards
  to the NUMA node can build on top of this (either add a 'node'
  parameter to pci_scan_bus_with_sysdata() or just update the node
  when it becomes known).

The patch was compile tested with various configurations (e.g., NUMAQ,
VISWS) and run-time tested on i386 and x86-64.  Unfortunately none of my
machines exhibited the bugs so caveat emptor.

Andy, could you please see if this fixes the NUMA issues you've seen?
Riku, does this fix "pci=noacpi" on your laptop?
Signed-off-by: NMuli Ben-Yehuda <muli@il.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: <riku.seppala@kymp.net>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch addresses some issues in x86/x86-64 acpi-cpufreq driver:

1.  Current memory allocation for acpi_perf_data is actually open-coded
   alloc_percpu().  The patch defines and handles acpi_perf_data as percpu
   data.  The code will be cleaner and easier to be maintained with this
   change.

2. Won't load driver in acpi_cpufreq_early_init() failure case.

3. Add __init for acpi_cpufreq_early_init().
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a missing =m constraint to the EDD-probing code, that could have
caused improper dead-code elimination.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Add memory operand constraint and write-only modifier to the inline
assembly to effect the writing of the EDID block to boot_params.edid_info.

Without this, gcc would think the EDID query was dead code and would
eliminate it.
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

C files should include the header files that prototype their functions.

Eliminates a sparse warning:
warning: symbol 'check_bugs' was not declared. Should it be static?
Signed-off-by: NJosh Triplett <josh@kernel.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On make install I get the this error:

...

sh /work/crazy/linux-git/linux-2.6/arch/i386/boot/install.sh
2.6.22-g4eb6bf6b arch/i386/boot/bzImage System.map "/boot"
/work/crazy/linux-git/linux-2.6/arch/i386/boot/install.sh: line 54:
/etc/lilo/install: No such file or directory
make[1]: *** [install] Error 127

...

I don't use and don't have lilo installed on this system. The attached
patch fixes the problem for me.
Signed-off-by: NGabriel Craciunescu <nix.or.die@googlemail.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/i386/kernel/apm.c: In function 'apm_init':
arch/i386/kernel/apm.c:2240: warning: format '%lx' expects type 'long
	unsigned int', but argument 3 has type 'u32'

apm_info.bios.offset is of type 'u32'.
Signed-off-by: NEugene Teo <eugeneteo@kernel.sg>
Acked-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Revert 7e92b4fc.  It broke Sébastien Dugué's
machine and Jeff said (persuasively)

  This seems like it will break decades-long-working stuff, in favor of
  breaking new ground in our favorite area, "trusting the BIOS."

  It's just not worth it for serial ports, IMO.  Serial ports are something
  that just shouldn't break at this late stage in the game.  My new Intel
  platform boxes don't even have serial ports, so I question the value of
  messing with serial port probing even more...  because...  just wait a year,
  and your box won't have a serial port either!  :)

  I certainly don't object to the use of platform devices (or isa_driver),
  but the probe change seems questionable.  That's sorta analagous to
  rewriting the floppy driver probe routine.  Sure you could do it...  but why
  risk all that damage and go through debugging all over again?

  It seems clear from this report that we cannot, should not, trust BIOS for
  something (a) so simple and (b) that has been working for over a decade.

Much discussion ensued and we've decided to have another go at all of this.

Cc: Sébastien Dugué <sebastien.dugue@bull.net>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Cc: Sascha Sommer <saschasommer@freenet.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The local variable "covered" is used without initialization in i386
acpi-cpufreq driver.  The initial value of covered should be 0.  The bug
will cause memory leak when hit.  The following patch fixes this bug.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some BIOSes require that sector buffers not cross 64K
boundaries.  As a result, we compute a dynamic address on the
setup heap.  Unfortunately, this address computation was just
totally wrong.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

End the "No setup signature found..." with a newline (the puts
routine will automatically add a carriage return.)
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Fix comments typos in new x86 boot code.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Commit 296699de broke building APM
support if CONFIG_PM_SLEEP is not set.

Reported by Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
[ Simplified a bit as suggested by Rafael.   -Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>