If we use the bootloader-provided stack pointer, we might end up in a
situation where the bootloader (incorrectly) pointed the stack in the
middle of our heap.  Catch this by simply comparing the computed heap
end value to the stack pointer minus the defined stack size.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Push video mode setup as late as possible; messages issued through the
BIOS interface after video mode setup will either not be seen (for
framebuffer modes) or will screw up the cursor (for text modes.)

In particular, this makes the EDD probing message show up correctly.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Tell the user to specify edd=off in the case of EDD probing hangs.
Per LKML discussion.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Add prototype for cmdline_find_option_bool() missing from:

    x86 setup: early cmdline parser handle boolean options

Also, fix up a minor formatting error in that patch.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Unnecessary capitals are shouting; no need for it here.
Thus, change "OK" to "ok" and add a space.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

On early boot, probing the Bios for EDD happens without any message.

Enhanced Disk Drive Services (EDD) is a mechanism to match x86 BIOS device
names (int13 device 80h) to Linux device names (e.g. /dev/sda, /dev/hda)

There are buggy Bios out there having problems with EDD. This can be problems
with the Bios itself or with addon cards, too.

This patch is adds an informational message on early boot.

CONFIG_EDD is not set with defconfig, but with allmodconfig (i.e. CONFIG_EDD=m)
so the EDD probe may be active on early boot on many systems nowadays.

I can tell, that the probe is active on SuSE distro and with that I have seen
more than one system hanging endlessly with those "black screen with a blinking
cursor in the the upper left" on installation, making it difficult for the end-
user to find out, what`s the issue.
For sure I have seen this on FujitsuSiemens PCs with i810 and with i815 chipset.

This one also honours the "quiet" bootparam.

Also see:
http://marc.info/?l=linux-kernel&m=119781937207969&w=2
http://marc.info/?l=linux-kernel&m=119783934032326&w=2
http://marc.info/?l=linux-kernel&m=119783678529100&w=2Signed-off-by: NRoland Kletzing <devzero@web.de>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This patch extends the early commandline parser to support boolean options.
The current version in mainline only supports parsing "option=arg" value pairs.

With this it should be easy making other messages like "Uncompressing kernel"
honour the "quiet" parameter, too.
Signed-off-by: NRoland Kletzing <devzero@web.de>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Fix the operand constraints for the segment accessor functions,
{rd,wr}{fs,gs}*.  In particular, the 8-bit functions used "r"
constraints instead of "q" constraints.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Display VESA graphics modes, with their mode IDs, in the vga=ask
menu.  Most VESA mode numbers are platform-dependent, so it helps to
have an easy way to display them.

Based in part on a patch by Petr Vandrovec <petr@vandrovec.name>.

Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

To set CR0.PE, use the X86_CR0_PE macro defined in
<asm/processor-flags.h> instead of hardcoding it as a constant (1).
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Intel VT doesn't like to engage when the protected-mode state isn't
fully initialized.  Make life easier for it by initializing LDTR (to
null) and TR (to a dummy hunk of low memory which will never actually
be touched.)
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Make the transition to protected mode more paranoid by having
back-to-back near jump (to synchronize the 386/486 prefetch queue) and
far jump (to set up the code segment.)

While we're at it, zero as many registers as practical (for future
expandability of the 32-bit entry interface) and enter 32-bit mode
with a valid stack.  Note that the 32-bit code cannot rely on this
stack, or we'll break all other existing users of the 32-bit
entrypoint, but it may make debugging hacks easier to write.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The boot GDT entries are common between 32- and 64-bit mode, so move
them to common code instead of having two identical copies.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Acked-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

get_segment_eip has similarities to convert_rip_to_linear(),
and is used in a similar context.  Move get_segment_eip to
step.c to allow easier consolidation.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Move out tick_nohz_stop_sched_tick() call from the loop in cpu_idle
same as 32-bit version.
Signed-off-by: NHiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

introduce the "asmregparm" calling convention: for functions
implemented in assembly with a fixed regparm input parameters
calling convention.

mark the semaphore and rwsem slowpath functions with that.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This implements ticket lock support for more than 255 CPUs on x86. The
code gets switched according to the configured NR_CPUS.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Simple coding style fixes.

no code changed:

   text    data     bss     dec     hex filename
   3139     576     194    3909     f45 fixup.o.before
   3139     576     194    3909     f45 fixup.o.after

  md5:
   9a3467057478b2d99962bdd448282eeb  fixup.o.before.asm
   9a3467057478b2d99962bdd448282eeb  fixup.o.after.asm
Signed-off-by: NPaolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use the fixup_exception() helper instead of the open-coded
search_extable() users.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Should be the last of the error_code tests that could use
the PF_ defines.  Makes X86_32|64 a little closer.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Small step towards unifying traps_32|64.c.  No functional
changes.  Pull out a small helper from an if() statement
in die().

Marked as __kprobes as eventually we will want to call this
from do_page_fault similar to how X86_64 does it.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The machine check handler registers ioctl handler that is called
with the BKL held. Changing to register unlocked_ioctl instead.
Also mce ioctl handler does not seem to need any lock protection.

To: Andi Kleen <andi@firstfloor.org>
Cc: linux-kernel@vger.kernel.org
Cc: kernel-janitors@vger.kernel.org

Change the Machine check handler to use unlocked_ioctl instead of
ioctl handler. Also the mce ioctl handler does not need any lock
protection.
Signed-off-by: NNikanth Karthikesan <knikanth@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

When the _PAGE_FOO constants are defined as (1ul << _PAGE_BIT_FOO), they
become unsigned longs.  In 32-bit PAE mode, these end up being
implicitly cast to 64-bit types when used to manipulate a pte, and
because they're unsigned the top 32-bits are 0, destroying the upper
bits of the pte.

When _PAGE_FOO constants are given a signed integer type, the cast to
64-bits will sign-extend so that the upper bits are all ones,
preserving the upper pte bits in manipulations.

Explain this in a prominent place.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The hypervisor doesn't allow PCD or PWT to be set on guest ptes, so
make sure they're masked out.  Also, fix up some previous mispatching.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Put all the defines for mapping pagetable operations to their native
versions (for the non-paravirt case) into one place.  Make the
corresponding changes to paravirt.h.

The tricky part here is that when a pagetable entry can't be updated
atomically (ie, 32-bit PAE), we need special handlers for pte_clear,
set_pte_atomic and set_pte_present.  However, the other two modes
don't need special handling for these, and can use a common
set_pte(_at) path.

[ mingo@elte.hu: fixes ]
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Move ZERO_PAGE/empty_zero_page to common place.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

&ptep->pte isn't always an unsigned long *, so cast it to avoid a warning.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Make various pte accessors common.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Fix various compilation problems as a result of changing pte_t.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Make sure pte_t, whatever its definition, has a pte element with type
pteval_t.  This allows common code to access it without needing to be
specifically parameterised on what pagetable mode we're compiling for.
For 32-bit, this means that pte_t becomes a union with "pte" and "{
pte_low, pte_high }" (PAE) or just "pte_low" (non-PAE).
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

fix sign extension bug in PTE_MASK / _PTE_CHG_MASK.

this resolves the following bootup crash on PAE systems:

[   94.710726] init[1]: segfault at 00000004 ip 49471cbb sp bff0c6c0 error 4
[   94.717764] init[1]: segfault at 00000004 ip 49471cbb sp bff0c6c0 error 4
[   94.724772] init[1]: segfault at 00000004 ip 49471cbb sp bff0c6c0 error 4
[   94.731777] init[1]: segfault at 00000004 ip 49471cbb sp bff0c6c0 error 4
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

based on:

 Subject: x86: unify pgtable accessors which use supported_pte_mask
 From: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Make users of supported_pte_mask common.  This has the side-effect of
introducing the variable for 32-bit non-PAE, but I think its a pretty
small cost to simplify the code.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

In 32-bit PAE, mask NX from pte_pfn, since it isn't part of the PFN.
This code is due for unification anyway, but this fixes a latent bug.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Unify functions to test and set bits in pagetable entries.

NOP: only moves existing code around, without any change to it.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

reorder. NOP.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

add new ops to 32-bit.

based on:

 Subject: x86/pgtable: unify pagetable accessors
 From: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

change the pte_mk inlines to the unified format. Non-NOP!

based on:

 Subject: x86/pgtable: unify pagetable accessors
 From: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

change the pte_dirty/* inlines to the unified format. Non-NOP!

based on:

 Subject: x86/pgtable: unify pagetable accessors
 From: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>