even on 64bit systems with less than 4G RAM, we can now use fixmap
to handle acpi SIT near end of ram.

change e820_end to e820_end_of_ram again?
or e820_ram_pfn?
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

and let 64-bit to fall back to use fixmap too.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix phys_pmd_init to make sure not to return bigger value than end.

also print out range split:1G/2M/4K in init_memory_mapping().
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix:

 arch/x86/kernel/built-in.o: In function `dmi_ignore_irq0_timer_override':
 boot.c:(.init.text+0x3ea4): undefined reference to `force_mask_ioapic_irq_2'
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Switch copy_user_generic_string(), copy_user_generic_unrolled() and
__copy_user_nocache() from custom tail handlers to generic
copy_user_tail_handle().
Signed-off-by: NVitaly Mayatskikh <v.mayatskih@gmail.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Introduce generic C routine for handling necessary tail operations after
protection fault in copy_*_user on x86.
Signed-off-by: NVitaly Mayatskikh <v.mayatskih@gmail.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NCyrill Gorcunov <gorcunov@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: akpm@linux-foundation.org
Cc: andi@firstfloor.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

to avoid warning from find_low_pfn_range for high pages size etc
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix:

arch/x86/kernel/acpi/boot.c: In function ‘dmi_ignore_irq0_timer_override’:
arch/x86/kernel/acpi/boot.c:1443: error: implicit declaration of function ‘force_mask_ioapic_irq_2’
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The problems are that, with the ACPI vs timer overring issue _fixed_,
after using the box for some time (between several seconds and 1 hour, at
random) processes get very high CPU loads (once I've got X using 107% of
the CPU, for example) and the system becomes unresponsive, as though there
were interrupts lost or something similar.

Andreas Herrman reproduced similar problems:

> Ok, now I've reproduced the stability problem.
> - Using tip/master,
> - reverting e38502eb8aa82314d5ab0eba45f50e6790dadd88 and
> - applying your patch from this posting
>   http://marc.info/?l=linux-kernel&m=121539354224562&w=4
>
> Starting X, firefox, gimp, tuxpaint and doing some drawing in tuxpaint
> results in a slow system. Drawing is almost not possible anymore --
> Selections of new colors, cursors etc. is performed with huge delay
> if it's performed at all.
>
> BTW, the code sets up timer IRQ as Virtual Wire IRQ:
>
> Jul  8 14:57:58 kodscha IO-APIC (apicid-pin) 2-22, 2-23 not connected.
> Jul  8 14:57:58 kodscha ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
> Jul  8 14:57:58 kodscha ...trying to set up timer as Virtual Wire IRQ... works.
>
> and both INT0 and INT2 of IOAPIC are masked:
>
> Jul  8 14:57:58 kodscha NR Dst Mask Trig IRR Pol Stat Dmod Deli Vect:
> Jul  8 14:57:58 kodscha 00 000 1    0    0   0   0    0    0    00
> Jul  8 14:57:58 kodscha 01 003 0    0    0   0   0    1    1    31
> Jul  8 14:57:58 kodscha 02 003 1    0    0   0   0    0    0    30
>
> I've also seen strange CPU utilization -- with syslog-ng:
>
> top - 15:33:06 up 35 min,  4 users,  load average: 1.70, 0.68, 0.37
> Tasks:  64 total,   4 running,  60 sleeping,   0 stopped,   0 zombie
> Cpu0  :  0.0%us,100.0%sy,  0.0%ni,  0.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu1  :  6.4%us, 87.2%sy,  0.0%ni,  5.8%id,  0.0%wa,  0.6%hi,  0.0%si,  0.0%st
> Mem:    895384k total,   283568k used,   611816k free,    35492k buffers
> Swap:  1959920k total,        0k used,  1959920k free,   163044k cached
>
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>  4632 root      20   0 17216  800  580 S  104  0.1   0:34.22 syslog-ng
> 28505 root      20   0  205m  11m 4024 S    6  1.3   0:21.16 X
> 28518 root      20   0 56292 5652 4492 S    1  0.6   0:01.80 fluxbox
>     1 root      20   0  3724  608  508 S    0  0.1   0:00.36 init
>
> So far I have no clue why C1E-idle in conjunction with virtual wire
> mode causes this strange behaviour.
>
> ... and I start to think about the root cause of all this.
>
> I've performed similar tests under X with the IRQ0/INT0 configuration and
> I did not see above symptoms.

So lets fall back to the IRQ0/INT0 configuration on this box.

This basically restores the dont-use-the-lapic-timer exception mechanism
that was unconditional on this box prior commit 8750bf5 ("x86: add C1E
aware idle function").
Signed-off-by: NIngo Molnar <mingo@elte.hu>

handle head and tail that are not aligned to big pages (2MB/1GB boundary).

with this patch, on system that support gbpages, change:

  last_map_addr: 1080000000 end: 1078000000

to:

  last_map_addr: 1078000000 end: 1078000000
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When system have 4g less ram installed, and acpi table sit
near end of ram, make max_pfn cover them too,
so 64bit kernel don't need to mess up fixmap.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Cc: "Suresh Siddha" <suresh.b.siddha@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Cc: "Nick Piggin" <npiggin@suse.de>
Cc: "Mark McLoughlin" <markmc@redhat.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: "Eduardo Habkost" <ehabkost@redhat.com>
Cc: "Vegard Nossum" <vegard.nossum@gmail.com>
Cc: "Stephen Tweedie" <sct@redhat.com>
Cc: "Jeremy Fitzhardinge" <jeremy@goop.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

prepare for overmapped patch

also printout last_map_addr together with end
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Remove them from the arch-specific file.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

x86_64 does not need it, but it won't have X86_INTEL_USERCOPY
defined either.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We also carry the unaligned version with us. Only x86_64 uses
it, but there's no problem in defining it.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Move both versions, which are highly similar, to uaccess.h.
Note that, for x86_64, X86_WP_WORKS_OK is always defined.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We also check user pointer in x86_64 put_user, the way i386 does.

In a separate patch for bisecting purposes.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

For both __put_user_x and __put_user_8 macros, pass the error
variable explicitly.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Move __get_user_asm and __get_user_size and __get_user_nocheck
to uaccess.h. This requires us to define a macro at __get_user_size
for the 64-bit access case.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Let the user of the macro specify the desired return.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Move both __put_user_asm and __put_user_size to
uaccess.h. i386 already had a special function for 64-bit access,
so for x86_64, we just define a macro with the same name.
Note that for X86_64, CONFIG_X86_WP_WORKS_OK will always
be defined, so the #else part will never be even compiled in.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Let the user of the macro specify the desired return.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Select X86_WP_WORKS_OK for x86_64 too.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Do it in a separate patch for bisectability.
Goal is to have put_user_size integrated.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Take it out of uaccess_32.h. Since it seems that no users
of the x86_64 exists, we simply pick the i386 version.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge versions of getuser from uaccess_32.h and uaccess_64.h into
uaccess.h. There is a part which is 64-bit only (for now), and for
that, we use a __get_user_8 macro.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Common parts of uaccess_32.h and uaccess_64.h
are put in uaccess.h. Bits in uaccess_32.h and
uaccess_64.h that come to this file are equal
except for comments and whitespaces differences.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Using explicit hexa (0xFFFFFFUL) introduces an unnecessary difference
between i386 and x86_64 because of the size of their long. Use -1UL instead.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Do not refer to the processor word-size with int, as it won't
work with x86_64. Use long instead.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Put the likely hint in access_ok. Just for
bisectability.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Our integration efforts broke a build with this function being used
with i386. Reason is "g" can put the operand in an imm32, which according
to The Book (tm), is invalid as the second operand.

This is actually a bug
in x86_64 too, since the x86_64 instruction set reference does not list
it as valid.

We probably didn't trigger this before due to the ammount of
registers available for 64-bit platforms. But that's just my guess.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

For i386, __range_not_ok is a better name than __range_ok, since
it returns 0 when it is in fact okay. Other than that,
both versions does not need the word size specifiers, and we remove them.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

putuser_32.S and putuser_64.S are merged into putuser.S.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In putuser_32.S and putuser_64.S, replace things like .quad, .long,
and explicit references to [r|e]ax for the apropriate macros
in asm/asm.h.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Remove them where unambiguous.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In putuser_64.S, do it the i386 way, and replace the code
in beginning and end of functions with macros, since it's
always the same thing. Save lines.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Instead of operating over a register we need to put back
into normal state afterwards (the memory position), just
sub from rbx, which is trashed anyway. We can save a few instructions.

Also, this is the i386 way.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>