Commit Graph

49 Commits

Author SHA1 Message Date
Andy Lutomirski 5a83d60c07 x86/fpu: Remove irq_ts_save() and irq_ts_restore()
Now that lazy FPU is gone, we don't use CR0.TS (except possibly in
KVM guest mode).  Remove irq_ts_save(), irq_ts_restore(), and all of
their callers.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm list <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/70b9b9e7ba70659bedcb08aba63d0f9214f338f2.1477951965.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-01 07:47:54 +01:00
Linus Torvalds c597b6bcd5 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Algorithms:
   - Add RSA padding algorithm

  Drivers:
   - Add GCM mode support to atmel
   - Add atmel support for SAMA5D2 devices
   - Add cipher modes to talitos
   - Add rockchip driver for rk3288
   - Add qat support for C3XXX and C62X"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (103 commits)
  crypto: hifn_795x, picoxcell - use ablkcipher_request_cast
  crypto: qat - fix SKU definiftion for c3xxx dev
  crypto: qat - Fix random config build issue
  crypto: ccp - use to_pci_dev and to_platform_device
  crypto: qat - Rename dh895xcc mmp firmware
  crypto: 842 - remove WARN inside printk
  crypto: atmel-aes - add debug facilities to monitor register accesses.
  crypto: atmel-aes - add support to GCM mode
  crypto: atmel-aes - change the DMA threshold
  crypto: atmel-aes - fix the counter overflow in CTR mode
  crypto: atmel-aes - fix atmel-ctr-aes driver for RFC 3686
  crypto: atmel-aes - create sections to regroup functions by usage
  crypto: atmel-aes - fix typo and indentation
  crypto: atmel-aes - use SIZE_IN_WORDS() helper macro
  crypto: atmel-aes - improve performances of data transfer
  crypto: atmel-aes - fix atmel_aes_remove()
  crypto: atmel-aes - remove useless AES_FLAGS_DMA flag
  crypto: atmel-aes - reduce latency of DMA completion
  crypto: atmel-aes - remove unused 'err' member of struct atmel_aes_dev
  crypto: atmel-aes - rework crypto request completion
  ...
2016-01-12 18:51:14 -08:00
Borislav Petkov 362f924b64 x86/cpufeature: Remove unused and seldomly used cpu_has_xx macros
Those are stupid and code should use static_cpu_has_safe() or
boot_cpu_has() instead. Kill the least used and unused ones.

The remaining ones need more careful inspection before a conversion can
happen. On the TODO.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1449481182-27541-4-git-send-email-bp@alien8.de
Cc: David Sterba <dsterba@suse.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19 11:49:55 +01:00
Geliang Tang 1d4bbc5a6f crypto: padlock-aes - use offset_in_page macro
Use offset_in_page macro instead of (addr & ~PAGE_MASK).

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-11-24 18:19:19 +08:00
Ingo Molnar df6b35f409 x86/fpu: Rename i387.h to fpu/api.h
We already have fpu/types.h, move i387.h to fpu/api.h.

The file name has become a misnomer anyway: it offers generic FPU APIs,
but is not limited to i387 functionality.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:30 +02:00
Kees Cook 5d26a105b5 crypto: prefix module autoloading with "crypto-"
This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:

https://lkml.org/lkml/2013/3/4/70

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-24 22:43:57 +08:00
Jussi Kivilinna e15aa3692d crypto: drivers - remove cra_list initialization
Initialization of cra_list is currently mixed, most ciphers initialize this
field and most shashes do not. Initialization however is not needed at all
since cra_list is initialized/overwritten in __crypto_register_alg() with
list_add(). Therefore perform cleanup to remove all unneeded initializations
of this field in 'crypto/drivers/'.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linux-geode@lists.infradead.org
Cc: Michal Ludvig <michal@logix.cz>
Cc: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
Cc: Varun Wadekar <vwadekar@nvidia.com>
Cc: Eric Bénard <eric@eukrea.com>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: Kent Yoder <key@linux.vnet.ibm.com>
Acked-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-08-01 17:47:28 +08:00
Andi Kleen 3bd391f056 crypto: Add support for x86 cpuid auto loading for x86 crypto drivers
Add support for auto-loading of crypto drivers based on cpuid features.
This enables auto-loading of the VIA and Intel specific drivers
for AES, hashing and CRCs.

Requires the earlier infrastructure patch to add x86 modinfo.
I kept it all in a single patch for now.

I dropped the printks when the driver cpuid doesn't match (imho
drivers never should print anything in such a case)

One drawback is that udev doesn't know if the drivers are used or not,
so they will be unconditionally loaded at boot up. That's better
than not loading them at all, like it often happens.

Cc: Dave Jones <davej@redhat.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jen Axboe <axboe@kernel.dk>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-26 16:48:10 -08:00
Jonathan Nieder c39cc377f9 crypto: padlock-aes - Make module loading even quieter when hardware is missing
When loading aes via the module alias, a padlock module failing to
load due to missing hardware is not particularly notable.  With
v2.6.27-rc1~1107^2~14 (crypto: padlock - Make module loading quieter
when hardware isn't available, 2008-07-03), the padlock-aes module
suppresses the relevant messages when the "quiet" flag is in use; but
better to suppress this particular message completely, since the
administrator can already distinguish such errors by the absence of a
message indicating initialization failing or succeeding.

This avoids occasional messages in syslog of the form

	padlock_aes: VIA PadLock not detected.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-08-03 14:07:11 +08:00
Linus Torvalds 27d189c02b Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (46 commits)
  hwrng: via_rng - Fix memory scribbling on some CPUs
  crypto: padlock - Move padlock.h into include/crypto
  hwrng: via_rng - Fix asm constraints
  crypto: n2 - use __devexit not __exit in n2_unregister_algs
  crypto: mark crypto workqueues CPU_INTENSIVE
  crypto: mv_cesa - dont return PTR_ERR() of wrong pointer
  crypto: ripemd - Set module author and update email address
  crypto: omap-sham - backlog handling fix
  crypto: gf128mul - Remove experimental tag
  crypto: af_alg - fix af_alg memory_allocated data type
  crypto: aesni-intel - Fixed build with binutils 2.16
  crypto: af_alg - Make sure sk_security is initialized on accept()ed sockets
  net: Add missing lockdep class names for af_alg
  include: Install linux/if_alg.h for user-space crypto API
  crypto: omap-aes - checkpatch --file warning fixes
  crypto: omap-aes - initialize aes module once per request
  crypto: omap-aes - unnecessary code removed
  crypto: omap-aes - error handling implementation improved
  crypto: omap-aes - redundant locking is removed
  crypto: omap-aes - DMA initialization fixes for OMAP off mode
  ...
2011-01-13 10:25:58 -08:00
Herbert Xu 2149308873 crypto: padlock - Move padlock.h into include/crypto
This patch moves padlock.h from drivers/crypto into include/crypto
so that it may be used by the via-rng driver.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-01-07 14:52:00 +11:00
Herbert Xu c054a076a1 crypto: padlock - Fix AES-CBC handling on odd-block-sized input
On certain VIA chipsets AES-CBC requires the input/output to be
a multiple of 64 bytes.  We had a workaround for this but it was
buggy as it sent the whole input for processing when it is meant
to only send the initial number of blocks which makes the rest
a multiple of 64 bytes.

As expected this causes memory corruption whenever the workaround
kicks in.

Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-11-04 14:38:39 -04:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Linus Torvalds d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
Chuck Ebbert e8edb3cbd7 crypto: padlock-aes - Use the correct mask when checking whether copying is required
Masking with PAGE_SIZE is just wrong...

Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-11-03 10:32:03 -05:00
Tejun Heo 390dfd95c5 percpu: make misc percpu symbols unique
This patch updates misc percpu related symbols such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* drivers/crypto/padlock-aes.c: s/last_cword/paes_last_cword/

* drivers/lguest/x86/core.c: s/last_cpu/lg_last_cpu/

* drivers/s390/net/netiucv.c: rename the variable used in a macro to
  avoid clashing with percpu symbol

* arch/mn10300/kernel/kprobes.c: replace current_ prefix with cur_ for
  static variables.  Please note that percpu symbol current_kprobe
  can't be changed as it's used by generic code.

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
2009-10-29 22:34:14 +09:00
Chuck Ebbert 8d8409f773 crypto: padlock-aes - work around Nano CPU errata in CBC mode
Extend previous workarounds for the prefetch bug to cover CBC mode,
clean up the code a bit.

Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Harald Welte <HaraldWelte@viatech.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-06-18 19:31:09 +08:00
Chuck Ebbert a76c1c23d0 crypto: padlock-aes - work around Nano CPU errata in ECB mode
The VIA Nano processor has a bug that makes it prefetch extra data
during encryption operations, causing spurious page faults. Extend
existing workarounds for ECB mode to copy the data to an temporary
buffer to avoid the problem.

Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Harald Welte <HaraldWelte@viatech.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-06-18 19:24:10 +08:00
Sebastian Andrzej Siewior d1c8b0a769 crypto: padlock - Enable on x86_64
Almost everything stays the same, we need just to use the extended registers
on the bit variant.

Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-06-02 14:04:31 +10:00
Herbert Xu acd246b749 crypto: padlock - Revert aes-all alias to aes
Since the padlock-aes driver doesn't require a fallback (it's
only padlock-sha that does), it should use the aes alias rather
than aes-all so that ones that do need a fallback can use it.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-04-21 13:55:20 +08:00
Herbert Xu a760a6656e crypto: api - Fix module load deadlock with fallback algorithms
With the mandatory algorithm testing at registration, we have
now created a deadlock with algorithms requiring fallbacks.
This can happen if the module containing the algorithm requiring
fallback is loaded first, without the fallback module being loaded
first.  The system will then try to test the new algorithm, find
that it needs to load a fallback, and then try to load that.

As both algorithms share the same module alias, it can attempt
to load the original algorithm again and block indefinitely.

As algorithms requiring fallbacks are a special case, we can fix
this by giving them a different module alias than the rest.  Then
it's just a matter of using the right aliases according to what
algorithms we're trying to find.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-02-26 14:06:31 +08:00
Herbert Xu 420a4b20c5 crypto: padlock - Avoid resetting cword on successive operations
Resetting the control word is quite expensive.  Fortunately this
isn't an issue for the common operations such as CBC and ECB as
the whole operation is done through a single call.  However, modes
such as LRW and XTS have to call padlock over and over again for
one operation which really hurts if each call resets the control
word.

This patch uses an idea by Sebastian Siewior to store the last
control word used on a CPU and only reset the control word if
that changes.

Note that any task switch automatically resets the control word
so we only need to be accurate with regard to the stored control
word when no task switches occur.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-25 11:01:20 +11:00
Suresh Siddha e49140120c crypto: padlock - fix VIA PadLock instruction usage with irq_ts_save/restore()
Wolfgang Walter reported this oops on his via C3 using padlock for
AES-encryption:

##################################################################

BUG: unable to handle kernel NULL pointer dereference at 000001f0
IP: [<c01028c5>] __switch_to+0x30/0x117
*pde = 00000000
Oops: 0002 [#1] PREEMPT
Modules linked in:

Pid: 2071, comm: sleep Not tainted (2.6.26 #11)
EIP: 0060:[<c01028c5>] EFLAGS: 00010002 CPU: 0
EIP is at __switch_to+0x30/0x117
EAX: 00000000 EBX: c0493300 ECX: dc48dd00 EDX: c0493300
ESI: dc48dd00 EDI: c0493530 EBP: c04cff8c ESP: c04cff7c
 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
Process sleep (pid: 2071, ti=c04ce000 task=dc48dd00 task.ti=d2fe6000)
Stack: dc48df30 c0493300 00000000 00000000 d2fe7f44 c03b5b43 c04cffc8 00000046
       c0131856 0000005a dc472d3c c0493300 c0493470 d983ae00 00002696 00000000
       c0239f54 00000000 c04c4000 c04cffd8 c01025fe c04f3740 00049800 c04cffe0
Call Trace:
 [<c03b5b43>] ? schedule+0x285/0x2ff
 [<c0131856>] ? pm_qos_requirement+0x3c/0x53
 [<c0239f54>] ? acpi_processor_idle+0x0/0x434
 [<c01025fe>] ? cpu_idle+0x73/0x7f
 [<c03a4dcd>] ? rest_init+0x61/0x63
 =======================

Wolfgang also found out that adding kernel_fpu_begin() and kernel_fpu_end()
around the padlock instructions fix the oops.

Suresh wrote:

These padlock instructions though don't use/touch SSE registers, but it behaves
similar to other SSE instructions. For example, it might cause DNA faults
when cr0.ts is set. While this is a spurious DNA trap, it might cause
oops with the recent fpu code changes.

This is the code sequence  that is probably causing this problem:

a) new app is getting exec'd and it is somewhere in between
   start_thread() and flush_old_exec() in the load_xyz_binary()

b) At pont "a", task's fpu state (like TS_USEDFPU, used_math() etc) is
   cleared.

c) Now we get an interrupt/softirq which starts using these encrypt/decrypt
   routines in the network stack. This generates a math fault (as
   cr0.ts is '1') which sets TS_USEDFPU and restores the math that is
   in the task's xstate.

d) Return to exec code path, which does start_thread() which does
   free_thread_xstate() and sets xstate pointer to NULL while
   the TS_USEDFPU is still set.

e) At the next context switch from the new exec'd task to another task,
   we have a scenarios where TS_USEDFPU is set but xstate pointer is null.
   This can cause an oops during unlazy_fpu() in __switch_to()

Now:

1) This should happen with or with out pre-emption. Viro also encountered
   similar problem with out CONFIG_PREEMPT.

2) kernel_fpu_begin() and kernel_fpu_end() will fix this problem, because
   kernel_fpu_begin() will manually do a clts() and won't run in to the
   situation of setting TS_USEDFPU in step "c" above.

3) This was working before the fpu changes, because its a spurious
   math fault  which doesn't corrupt any fpu/sse registers and the task's
   math state was always in an allocated state.

With out the recent lazy fpu allocation changes, while we don't see oops,
there is a possible race still present in older kernels(for example,
while kernel is using kernel_fpu_begin() in some optimized clear/copy
page and an interrupt/softirq happens which uses these padlock
instructions generating DNA fault).

This is the failing scenario that existed even before the lazy fpu allocation
changes:

0. CPU's TS flag is set

1. kernel using FPU in some optimized copy  routine and while doing
kernel_fpu_begin() takes an interrupt just before doing clts()

2. Takes an interrupt and ipsec uses padlock instruction. And we
take a DNA fault as TS flag is still set.

3. We handle the DNA fault and set TS_USEDFPU and clear cr0.ts

4. We complete the padlock routine

5. Go back to step-1, which resumes clts() in kernel_fpu_begin(), finishes
the optimized copy routine and does kernel_fpu_end(). At this point,
we have cr0.ts again set to '1' but the task's TS_USEFPU is stilll
set and not cleared.

6. Now kernel resumes its user operation. And at the next context
switch, kernel sees it has do a FP save as TS_USEDFPU is still set
and then will do a unlazy_fpu() in __switch_to(). unlazy_fpu()
will take a DNA fault, as cr0.ts is '1' and now, because we are
in __switch_to(), math_state_restore() will get confused and will
restore the next task's FP state and will save it in prev tasks's FP state.
Remember, in __switch_to() we are already on the stack of the next task
but take a DNA fault for the prev task.

This causes the fpu leakage.

Fix the padlock instruction usage by calling them inside the
context of new routines irq_ts_save/restore(), which clear/restore cr0.ts
manually in the interrupt context. This will not generate spurious DNA
in the  context of the interrupt which will fix the oops encountered and
the possible FPU leakage issue.

Reported-and-bisected-by: Wolfgang Walter <wolfgang.walter@stwm.de>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-13 22:02:26 +10:00
Jeremy Katz b43e726b32 crypto: padlock - Make module loading quieter when hardware isn't available
When loading aes or sha256 via the module aliases, the padlock modules
also try to get loaded.  Make the error message for them not being
present only be a NOTICE rather than an ERROR so that use of 'quiet'
will suppress the messages

Signed-off-by: Jeremy Katz <katzj@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:16 +08:00
Sebastian Siewior 7dc748e4e7 [CRYPTO] padlock-aes: Use generic setkey function
The Padlock AES setkey routine is the same as exported by the generic
implementation. So we could use it.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Cc: Michal Ludvig <michal@logix.cz>
Tested-by: Stefan Hellermann <stefan@the2masters.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21 10:19:34 +08:00