This patch updates the list of transforms we support and clarifies that
the Block Ciphers interface in fact supports all ciphers including stream
ciphers.

It also removes the obsolete Configuration Notes section and adds the
linux-crypto mailing list as the primary bug reporting address.

Finally it documents the fact that setkey should only be called from
user context.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch converts the crypto scatterwalk code to use the generic
scatterlist chaining rather the version specific to crypto.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

alpha:

drivers/crypto/hifn_795x.c: In function 'ablkcipher_walk_init':
drivers/crypto/hifn_795x.c:1231: error: implicit declaration of function 'sg_init_table'
drivers/crypto/hifn_795x.c:1243: error: implicit declaration of function 'sg_set_page'
drivers/crypto/hifn_795x.c: In function 'ablkcipher_walk_exit':
drivers/crypto/hifn_795x.c:1257: error: implicit declaration of function 'sg_page'
drivers/crypto/hifn_795x.c:1257: warning: passing argument 1 of '__free_pages' makes pointer from integer without a cast
drivers/crypto/hifn_795x.c: In function 'ablkcipher_add':
drivers/crypto/hifn_795x.c:1278: warning: passing argument 1 of 'kmap_atomic' makes pointer from integer without a cast
drivers/crypto/hifn_795x.c: In function 'ablkcipher_walk':
drivers/crypto/hifn_795x.c:1336: warning: passing argument 1 of 'kmap_atomic' makes pointer from integer without a cast
drivers/crypto/hifn_795x.c: In function 'hifn_setup_session':
drivers/crypto/hifn_795x.c:1465: warning: assignment makes pointer from integer without a cast
drivers/crypto/hifn_795x.c:1469: warning: assignment makes pointer from integer without a cast
drivers/crypto/hifn_795x.c:1472: warning: assignment makes pointer from integer without a cast
drivers/crypto/hifn_795x.c: In function 'ablkcipher_get':
drivers/crypto/hifn_795x.c:1593: warning: passing argument 1 of 'kmap_atomic' makes pointer from integer without a cast
{standard input}: Assembler messages:
{standard input}:7: Warning: setting incorrect section attributes for .got
drivers/crypto/hifn_795x.c: In function 'hifn_process_ready':
drivers/crypto/hifn_795x.c:1653: warning: passing argument 1 of 'kmap_atomic' makes pointer from integer without a cast
drivers/crypto/hifn_795x.c: In function 'hifn_probe':
drivers/crypto/hifn_795x.c:2438: error: 'DMA_32BIT_MASK' undeclared (first use in this function)
drivers/crypto/hifn_795x.c:2438: error: (Each undeclared identifier is reported only once
drivers/crypto/hifn_795x.c:2438: error: for each function it appears in.)
drivers/crypto/hifn_795x.c:2443: warning: format '%d' expects type 'int', but argument 4 has type 'long int'
drivers/crypto/hifn_795x.c:2443: warning: format '%d' expects type 'int', but argument 4 has type 'long int'
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The HIFN driver is currently selectable on s390 but wont compile.
Since it looks like HIFN needs PCI make the Kconfig dependent on PCI,
which is not available on s390.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch forces HIFN driver to invoke crypto request callbacks from
tasklet (softirq context) instead of hardirq context, since network
stack expects it to be called from bottom halves.

It is done by simply scheduling callback invocation via dedicated
tasklet. Workqueue solution was dropped because of tooo slow
rescheduling performance (7 times slower than tasklet, for mode details
one can check this link:
http://tservice.net.ru/~s0mbre/blog/devel/other/2007_11_09.html).

Driver passed all AES and DES tests in tcryt.c module.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Resubmitting this patch which extends sha256_generic.c to support SHA-224 as
described in FIPS 180-2 and RFC 3874. HMAC-SHA-224 as described in RFC4231
is then supported through the hmac interface.

Patch includes test vectors for SHA-224 and HMAC-SHA-224.

SHA-224 chould be chosen as a hash algorithm when 112 bits of security
strength is required.

Patch generated against the 2.6.24-rc1 kernel and tested against
2.6.24-rc1-git14 which includes fix for scatter gather implementation for HMAC.
Signed-off-by: Jonathan Lynch <jonathan.lynch@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The Geode AES crypto engine supports only 128 bit long key. This
patch adds fallback for other key sizes which are required by the
AES standard.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Acked-by: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The setkey() function can be shared with the generic algorithm.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

NO other block mode is M by default.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The setkey() function can be shared with the generic algorithm.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch exports four tables and the set_key() routine. This ressources
can be shared by other AES implementations (aes-x86_64 for instance).
The decryption key has been turned around (deckey[0] is the first piece
of the key instead of deckey[keylen+20]). The encrypt/decrypt functions
are looking now identical (except they are using different tables and
key).
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch adds countersize to CTR mode.
The template is now ctr(algo,noncesize,ivsize,countersize).

For example, ctr(aes,4,8,4) indicates the counterblock
will be composed of a salt/nonce that is 4 bytes, an iv
that is 8 bytes and the counter is 4 bytes.

When noncesize + ivsize < blocksize, CTR initializes the
last block - ivsize - noncesize portion of the block to
zero.  Otherwise the counter block is composed of the IV
(and nonce if necessary).

If noncesize + ivsize == blocksize, then this indicates that
user is passing in entire counterblock. Thus countersize
indicates the amount of bytes in counterblock to use as
the counter for incrementing. CTR will increment counter
portion by 1, and begin encryption with that value.

Note that CTR assumes the counter portion of the block that
will be incremented is stored in big endian.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Move huge unrolled pieces of code (3 screenfuls) at the end of
128/256 key setup routines into common camellia_setup_tail(),
convert it to loop there.
Loop is still unrolled six times, so performance hit is very small,
code size win is big.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Optimize GETU32 to use 4-byte memcpy (modern gcc will convert
such memcpy to single move instruction on i386).
Original GETU32 did four byte fetches, and shifted/XORed those.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Rename some macros to shorter names: CAMELLIA_RR8 -> ROR8,
making it easier to understand that it is just a right rotation,
nothing camellia-specific in it.
CAMELLIA_SUBKEY_L() -> SUBKEY_L() - just shorter.

Move be32 <-> cpu conversions out of en/decrypt128/256 and into
camellia_en/decrypt - no reason to have that code duplicated twice.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Move code blocks around so that related pieces are closer together:
e.g. CAMELLIA_ROUNDSM macro does not need to be separated
from the rest of the code by huge array of constants.

Remove unused macros (COPY4WORD, SWAP4WORD, XOR4WORD[2])

Drop SUBL(), SUBR() macros which only obscure things.
Same for CAMELLIA_SP1110() macro and KEY_TABLE_TYPE typedef.

Remove useless comments:
/* encryption */ -- well it's obvious enough already!
void camellia_encrypt128(...)

Combine swap with copying at the beginning/end of encrypt/decrypt.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Currently twofish cipher key setup code
has unrolled loops - approximately 70-100
instructions are repeated 40 times.

As a result, twofish module is the biggest module
in crypto/*.

Unrolling produces x2.5 more code (+18k on i386), and speeds up key
setup by 7%:

	unrolled: twofish_setkey/sec: 41128
	    loop: twofish_setkey/sec: 38148
	CALC_K256: ~100 insns each
	CALC_K192: ~90 insns
	   CALC_K: ~70 insns

Attached patch removes this unrolling.

$ size */twofish_common.o
   text    data     bss     dec     hex filename
  37920       0       0   37920    9420 crypto.org/twofish_common.o
  13209       0       0   13209    3399 crypto/twofish_common.o

Run tested (modprobe tcrypt reports ok). Please apply.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch moves macros in geode-aes.c into geode-aes.h.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The code waits in a busy loop until the hardware finishes the encryption
or decryption process. This wants a cpu_relax() :)
The busy loop finishes either if the encryption is done or if the counter
is zero. If the latter is true than the hardware failed. Since this
should not happen, leave sith a BUG().
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

It is enough if the IV is copied before and after the while loop.
With DM-Crypt is seems not be required to save the IV after encrytion
because a new one is used in the request (dunno about other users).
It is not save to load the IV within while loop and not save afterwards
because we mill end up with the wrong IV if the request goes consists
of more than one page.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This three defines are used in all AES related hardware.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

alias isn't required because the module provides PCI ids.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

HIFN driver update to use DES weak key checks (exported in this patch).
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch creates include/crypto/des.h for common macros shared between
DES implementations.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This is a driver for HIFN 795x crypto accelerator chips.

It passed all tests for AES, DES and DES3_EDE except weak test for DES,
since hardware can not determine weak keys.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

This patch implements CTR mode for IPsec.
It is based off of RFC 3686.

Please note:
1. CTR turns a block cipher into a stream cipher.
Encryption is done in blocks, however the last block
may be a partial block.

A "counter block" is encrypted, creating a keystream
that is xor'ed with the plaintext. The counter portion
of the counter block is incremented after each block
of plaintext is encrypted.
Decryption is performed in same manner.

2. The CTR counterblock is composed of,
        nonce + IV + counter

The size of the counterblock is equivalent to the
blocksize of the cipher.
        sizeof(nonce) + sizeof(IV) + sizeof(counter) = blocksize

The CTR template requires the name of the cipher
algorithm, the sizeof the nonce, and the sizeof the iv.
        ctr(cipher,sizeof_nonce,sizeof_iv)

So for example,
        ctr(aes,4,8)
specifies the counterblock will be composed of 4 bytes
from a nonce, 8 bytes from the iv, and 4 bytes for counter
since aes has a blocksize of 16 bytes.

3. The counter portion of the counter block is stored
in big endian for conformance to rfc 3686.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The previous patch fixed spurious read faults from occuring by copying
the data if we happen to have a single block at the end of a page.  It
appears that gcc cannot guarantee 16-byte alignment in the kernel with
__attribute__.  The following report from Torben Viets shows a buffer
that's only 8-byte aligned:

> eneral protection fault: 0000 [#1]
> Modules linked in: xt_TCPMSS xt_tcpmss iptable_mangle ipt_MASQUERADE
> xt_tcpudp xt_mark xt_state iptable_nat nf_nat nf_conntrack_ipv4
> iptable_filter ip_tables x_tables pppoe pppox af_packet ppp_generic slhc
> aes_i586
> CPU:    0
> EIP:    0060:[<c035b828>]    Not tainted VLI
> EFLAGS: 00010292   (2.6.23.12 #7)
> EIP is at aes_crypt_copy+0x28/0x40
> eax: f7639ff0   ebx: f6c24050   ecx: 00000001   edx: f6c24030
> esi: f7e89dc8   edi: f7639ff0   ebp: 00010000   esp: f7e89dc8

Since the hardware must have 16-byte alignment, the following patch fixes
this by open coding the alignment adjustment.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

The xcryptecb instruction always processes an even number of blocks so
we need to ensure th existence of an extra block if we have to process
an odd number of blocks.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

As it is crypto_remove_spawn may try to unregister an instance which is
yet to be registered.  This patch fixes this by checking whether the
instance has been registered before attempting to remove it.

It also removes a bogus cra_destroy check in crypto_register_instance as
1) it's outside the mutex;
2) we have a check in __crypto_register_alg already.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

It seems that newer versions of gcc have regressed in their abilities to
analyse initialisations.  This patch moves the initialisations up to avoid
the warnings.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86:
  x86: simplify "make ARCH=x86" and fix kconfig all.config
  x86: reboot fixup for wrap2c board
  x86: check boundary in count setup resource
  x86: fix reboot with no keyboard attached
  x86: add hpet sanity checks
  x86: on x86_64, correct reading of PC RTC when update in progress in time_64.c
  x86: fix freeze in x86_64 RTC update code in time_64.c
  ntp: fix typo that makes sync_cmos_clock erratic
  Remove x86 merge artifact from top Makefile
  x86: fixup cpu_info array conversion
  x86: show cpuinfo only for online CPUs
  x86: fix cpu-hotplug regression
  x86: ignore the sys_getcpu() tcache parameter
  x86: voyager use correct header file name
  x86: fix smp init sections
  x86: fix voyager_cat_init section
  x86: fix bogus memcpy in es7000_check_dsdt()

Simplify "make ARCH=x86" and fix kconfig so we again can set 64BIT in
all.config.

For a fix the diffstat is nice:
 6 files changed, 3 insertions(+), 36 deletions(-)

The patch reverts these commits:
 - 0f855aa6 ("kconfig: add helper to set
   config symbol from environment variable")
 - 2a113281 ("kconfig: use $K64BIT to
   set 64BIT with all*config targets")

Roman Zippel pointed out that kconfig supported string compares so
the additional complexity introduced by the above two patches were
not needed.

With this patch we have following behaviour:

  # make {allno,allyes,allmod,rand}config [ARCH=...]
  option \ host arch      | 32bit         | 64bit
  =====================================================
  ./.                     | 32bit         | 64bit
  ARCH=x86                | 32bit         | 32bit
  ARCH=i386               | 32bit         | 32bit
  ARCH=x86_64             | 64bit         | 64bit

The general rule are that ARCH= and native architecture takes
precedence over the configuration.

So make ARCH=i386 [whatever] will always build a 32-bit kernel
no matter what the configuration says.  The configuration will
be updated to 32-bit if it was configured to 64-bit and the
other way around.

This behaviour is consistent with previous behaviour so no
suprises here.

make ARCH=x86 will per default result in a 32-bit kernel but as
the only ARCH= value x86 allow the user to select between 32-bit
and 64-bit using menuconfig.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Herrmann <aherrman@arcor.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Simplify "make ARCH=x86" and fix kconfig so we again
can set 64BIT in all.config.

For a fix the diffstat is nice:
 6 files changed, 3 insertions(+), 36 deletions(-)

The patch reverts these commits:
0f855aa6
-> kconfig: add helper to set config symbol from environment variable

2a113281
-> kconfig: use $K64BIT to set 64BIT with all*config targets

Roman Zippel pointed out that kconfig supported string
compares so the additional complexity introduced by the
above two patches were not needed.

With this patch we have following behaviour:

# make {allno,allyes,allmod,rand}config [ARCH=...]
option \ host arch      | 32bit         | 64bit
=====================================================
./.                     | 32bit         | 64bit
ARCH=x86                | 32bit         | 32bit
ARCH=i386               | 32bit         | 32bit
ARCH=x86_64             | 64bit         | 64bit

The general rule are that ARCH= and native architecture
takes precedence over the configuration.
So make ARCH=i386 [whatever] will always build a 32-bit
kernel no matter what the configuration says.
The configuration will be updated to 32-bit if it was
configured to 64-bit and the other way around.

This behaviour is consistent with previous behaviour so
no suprises here.

make ARCH=x86 will per default result in a 32-bit kernel
but as the only ARCH= value x86 allow the user to select
between 32-bit and 64-bit using menuconfig. 
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Herrmann <aherrman@arcor.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>

Needed to make the wireless board, WRAP2C reboot.

Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

need to check info->res_num less than PCI_BUS_NUM_RESOURCES, so
info->bus->resource[info->res_num] = res will not beyond of bus resource
array when acpi returns too many resource entries.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Gary Hade <gary.hade@us.ibm.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Attempt to fix http://bugzilla.kernel.org/show_bug.cgi?id=8378

Hiroto Shibuya wrote to tell me that he has a VIA EPIA-EK10000 which
suffers from the reboot problem when no keyboard is attached.  My first
patch works for him:

  http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=59f4e7d572980a521b7bdba74ab71b21f5995538

But the latest patch does not work for him :

  http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=8b93789808756bcc1e5c90c99f1b1ef52f839a51

We found that it was necessary to also set the "disable keyboard" flag in
the command byte, as the first patch was doing.  The second patch tries to
minimally modify the command byte, but it is not enough.

Please consider this simple one-line patch to help people with low end VIA
motherboards reboot when no keyboard is attached.  Hiroto Shibuya has
verified that this works for him (as I no longer have an afflicted
machine).


Additional discussion:

Note that original patch from Truxton DOES
disable keyboard and this has been in main tree since 2.6.14, thus it must have
quite a bit of air time already.

http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.14.y.git;a=commit;h=59f4e7d572980a521b7bdba74ab71b21f5995538

Note that he only mention "System flag" in the description and comment, but
in the code, "disable keyboard" flag is set.

  outb(0x14, 0x60);       /* set "System flag" */

In 2.6.23, he made a change to read the current byte and then mask the flags,
but along this change,  he only set the "System flag" and dropped the setting
of "disable keyboard" flag.

http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.23.y.git;a=commit;h=8b93789808756bcc1e5c90c99f1b1ef52f839a51

   outb(cmd | 0x04, 0x60); /* set "System flag" */

So my request is to restore the setting of disable keyboard flag which has been
there since 2.6.14 but disappeared in 2.6.23.

Cc: Lee Garrett <lee-in-berlin@web.de>
Cc: "Hiroto Shibuya" <hiroto.shibuya@gmail.com>
Cc: Natalie Protasevich <protasnb@gmail.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Aristeu Rozanski <aris@ruivo.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Some BIOSes advertise HPET at 0x0. We really do no want to 
allocate a resource there. Check for it and leave early.

Other BIOSes tell us the HPET is at 0xfed0000000000000 
instead of 0xfed00000. Add a check and fix it up with a warning
on user request.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Correct potentially unstable PC RTC time register reading in time_64.c

Stop the use of an incorrect technique for reading the standard PC RTC
timer, which is documented to "disconnect" time registers from the bus
while updates are in progress.  The use of UIP flag while interrupts
are disabled to protect a 244 microsecond window is one of the
Motorola spec sheet's documented ways to read the RTC time registers
reliably.

tglx: removed locking changes from original patch, as they gain nothing
(read_persistent_clock is only called during boot, suspend, resume - so
no hot path affected) and conflict with the paravirt locking scheme
(see 32bit code), which we do not want to complicate for no benefit.
Signed-off-by: David P. Reed <dpreed@reed.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Fix hard freeze on x86_64 when the ntpd service calls 
update_persistent_clock()

A repeatable but randomly timed freeze has been happening in Fedora 6
and 7 for the last year, whenever I run the ntpd service on my AMD64x2
HP Pavilion dv9000z laptop.  This freeze is due to the use of
spin_lock(&rtc_lock) under the assumption (per a bad comment) that
set_rtc_mmss is called only with interrupts disabled.  The call from
ntp.c to update_persistent_clock is made with interrupts enabled.
Signed-off-by: David P. Reed <dpreed@reed.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>