sha224 AEAD test fails with:
[ 2.803125] talitos ff020000.crypto: DEUISR 0x00000000_00000000
[ 2.808743] talitos ff020000.crypto: MDEUISR 0x80100000_00000000
[ 2.814678] talitos ff020000.crypto: DESCBUF 0x20731f21_00000018
[ 2.820616] talitos ff020000.crypto: DESCBUF 0x0628d64c_00000010
[ 2.826554] talitos ff020000.crypto: DESCBUF 0x0631005c_00000018
[ 2.832492] talitos ff020000.crypto: DESCBUF 0x0628d664_00000008
[ 2.838430] talitos ff020000.crypto: DESCBUF 0x061b13a0_00000080
[ 2.844369] talitos ff020000.crypto: DESCBUF 0x0631006c_00000080
[ 2.850307] talitos ff020000.crypto: DESCBUF 0x0631006c_00000018
[ 2.856245] talitos ff020000.crypto: DESCBUF 0x063100ec_00000000
[ 2.884972] talitos ff020000.crypto: failed to reset channel 0
[ 2.890503] talitos ff020000.crypto: done overflow, internal time out, or rngu error: ISR 0x20000000_00020000
[ 2.900652] alg: aead: encryption failed on test 1 for authenc-hmac-sha224-cbc-3des-talitos: ret=22
This is due to SHA224 not being supported by the HW. Allthough for
hash we are able to init the hash context by SW, it is not
possible for AEAD. Therefore SHA224 AEAD has to be deactivated.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Crypto manager test report the following failures:
[ 3.061081] alg: skcipher: setkey failed on test 5 for ecb-des-talitos: flags=100
[ 3.069342] alg: skcipher-ddst: setkey failed on test 5 for ecb-des-talitos: flags=100
[ 3.077754] alg: skcipher-ddst: setkey failed on test 5 for ecb-des-talitos: flags=100
This is due to setkey being expected to detect weak keys.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds aes-gcm support to crypto4xx.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch enhances existing interfaces and
functions to support AEAD ciphers in the next
patches.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Thanks to the big overhaul of crypto4xx_build_pd(), the request-local
sa_in, sa_out and state_record allocation can be simplified.
There's no need to setup any dma coherent memory anymore and
much of the support code can be removed.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the crypto4xx device is continuously loaded by dm-crypt
and ipsec work, it will start to work intermittent after a
few (between 20-30) seconds, hurting throughput and latency.
This patch contains various stability improvements in order
to fix this issue. So far, the hardware has survived more
than a day without suffering any stalls under the continuous
load.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto4xx_core.c:179:6: warning: symbol 'crypto4xx_free_state_record'
was not declared. Should it be static?
crypto4xx_core.c:331:5: warning: symbol 'crypto4xx_get_n_gd'
was not declared. Should it be static?
crypto4xx_core.c:652:6: warning: symbol 'crypto4xx_return_pd'
was not declared. Should it be static?
crypto4xx_return_pd() is not used by anything. Therefore it is removed.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch overhauls and fixes code related to crypto4xx_build_pd()
* crypto4xx_build_pd() did not handle chained source scatterlist.
This is fixed by replacing the buggy indexed-access of &src[idx]
with sg_next() in the gather array setup loop.
* The redundant is_hash, direction, save_iv and pd_ctl members
in the crypto4xx_ctx struct have been removed.
- is_hash can be derived from the crypto_async_request parameter.
- direction is already part of the security association's
bf.dir bitfield.
- save_iv is unused.
- pd_ctl always had the host_ready bit enabled anyway.
(the hash_final case is rather pointless, since the ahash
code has been deactivated).
* make crypto4xx_build_pd()'s caller responsible for converting
the IV to the LE32 format.
* change crypto4xx_ahash_update() and crypto4xx_ahash_digest() to
initialize a temporary destination scatterlist. This allows the
removal of an ugly cast of req->result (which is a pointer to an
u8-array) to a scatterlist pointer.
* change crypto4xx_build_pd() return type to int. After all
it returns -EINPROGRESS/-EBUSY.
* fix crypto4xx_build_pd() thread-unsafe sa handling.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The hardware expects that the keys, IVs (and inner/outer hashes)
are in the le32 format.
This patch changes all hardware interface declarations to use
the correct LE32 data format for each field.
In order to pass __CHECK_ENDIAN__ checks, crypto4xx_memcpy_le
has to be honest about the endianness of its parameters.
The function was split and moved to the common crypto4xx_core.h
header. This allows the compiler to generate better code if the
sizes/len is a constant (various *_IV_LEN).
Please note that the hardware isn't consistent with the endiannes
of the save_digest field in the state record struct though.
The hashes produced by GHASH and CBC (for CCM) will be in LE32.
Whereas md5 and sha{1/,256,...} do not need any conversion.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Previously, If the crypto4xx driver used all available
security contexts, it would simply refuse new requests
with -EAGAIN. CRYPTO_TFM_REQ_MAY_BACKLOG was ignored.
in case of dm-crypt.c's crypt_convert() function this was
causing the following errors to manifest, if the system was
pushed hard enough:
| EXT4-fs warning (dm-1): ext4_end_bio:314: I/O error -5 writing to ino ..
| EXT4-fs warning (dm-1): ext4_end_bio:314: I/O error -5 writing to ino ..
| EXT4-fs warning (dm-1): ext4_end_bio:314: I/O error -5 writing to ino ..
| JBD2: Detected IO errors while flushing file data on dm-1-8
| Aborting journal on device dm-1-8.
| EXT4-fs error : ext4_journal_check_start:56: Detected aborted journal
| EXT4-fs (dm-1): Remounting filesystem read-only
| EXT4-fs : ext4_writepages: jbd2_start: 2048 pages, inode 498...; err -30
(This did cause corruptions due to failed writes)
To fix this mess, the crypto4xx driver needs to notifiy the
user to slow down. This can be achieved by returning -EBUSY
on requests, once the crypto hardware was falling behind.
Note: -EBUSY has two different meanings. Setting the flag
CRYPTO_TFM_REQ_MAY_BACKLOG implies that the request was
successfully queued, by the crypto driver. To achieve this
requirement, the implementation introduces a threshold check and
adds logic to the completion routines in much the same way as
AMD's Cryptographic Coprocessor (CCP) driver do.
Note2: Tests showed that dm-crypt starved ipsec traffic.
Under load, ipsec links dropped to 0 Kbits/s. This is because
dm-crypt's callback would instantly queue the next request.
In order to not starve ipsec, the driver reserves a small
portion of the available crypto contexts for this purpose.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If crypto4xx is used in conjunction with dm-crypt, the available
ring buffer elements are not enough to handle the load properly.
On an aes-cbc-essiv:sha256 encrypted swap partition the read
performance is abyssal: (tested with hdparm -t)
/dev/mapper/swap_crypt:
Timing buffered disk reads: 14 MB in 3.68 seconds = 3.81 MB/sec
The patch increases both PPC4XX_NUM_SD and PPC4XX_NUM_PD to 256.
This improves the performance considerably:
/dev/mapper/swap_crypt:
Timing buffered disk reads: 104 MB in 3.03 seconds = 34.31 MB/sec
Furthermore, PPC4XX_LAST_SD, PPC4XX_LAST_GD and PPC4XX_LAST_PD
can be easily calculated from their respective PPC4XX_NUM_*
constant.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes a type mismatch error that I accidentally
introduced when I moved and refactored the dynamic_contents
helpers.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
I used aes-cbc as a template for ofb. But sadly I forgot
to update set_key method to crypto4xx_setkey_aes_ofb().
this was caught by the testmgr:
alg: skcipher: Test 1 failed (invalid result) on encr. for ofb-aes-ppc4xx
00000000: 76 49 ab ac 81 19 b2 46 ce e9 8e 9b 12 e9 19 7d
00000010: 50 86 cb 9b 50 72 19 ee 95 db 11 3a 91 76 78 b2
00000020: 73 be d6 b8 e3 c1 74 3b 71 16 e6 9e 22 22 95 16
00000030: 3f f1 ca a1 68 1f ac 09 12 0e ca 30 75 86 e1 a7
With the correct set_key method, the aes-ofb cipher passes the test.
name : ofb(aes)
driver : ofb-aes-ppc4xx
module : crypto4xx
priority : 300
refcnt : 1
selftest : passed
internal : no
type : ablkcipher
async : yes
blocksize : 16
min keysize : 16
max keysize : 32
ivsize : 16
geniv : <default>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The hmac_mc parameter of set_dynamic_sa_command_1()
was defined but not used. On closer inspection it
turns out, it was never wired up.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The code is simplified by using two __be64 values for the operation
instead of using two arrays of u8. This allows to get rid of the memory
alignment code. In addition, the crypto_xor can be replaced with a
native XOR operation. Finally, the definition of the variables is
re-arranged such that the data structures come before simple variables
to potentially reduce memory space.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
DH_KPP_SECRET_MIN_SIZE and dh_data_size() are both returning
unsigned values.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
p->key_size, p->p_size, p->g_size are all of unsigned int type.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ECDH_KPP_SECRET_MIN_SIZE and params->key_size are both returning
unsigned values.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
pr_err() messages should terminated with a new-line to avoid
other messages being concatenated onto the end.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the cipher name does not start with 'ecb(' we should bail out, as done
in the 'create()' function in 'crypto/xts.c'.
Fixes: 700cb3f5fe ("crypto: lrw - Convert to skcipher")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
All error handling paths 'goto err_drop_spawn' except this one.
In order to avoid some resources leak, we should do it as well here.
Fixes: 700cb3f5fe ("crypto: lrw - Convert to skcipher")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The usage of of_device_get_match_data reduce the code size a bit.
Furthermore, it prevents an improbable dereference when
of_match_device() return NULL.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The usage of of_device_get_match_data reduce the code size a bit.
Furthermore, it prevents an improbable dereference when
of_match_device() return NULL.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The usage of of_device_get_match_data reduce the code size a bit.
Furthermore, it prevents an improbable dereference when
of_match_device() return NULL.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The variable len is set to zero, never read and then later updated
to p - name, so clearly the zero'ing of len is redundant and
can be removed.
Detected by clang scan-build:
" warning: Value stored to 'len' is never read"
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the algorithm we're parallelizing is asynchronous we might change
CPUs between padata_do_parallel() and padata_do_serial(). However, we
don't expect this to happen as we need to enqueue the padata object into
the per-cpu reorder queue we took it from, i.e. the same-cpu's parallel
queue.
Ensure we're not switching CPUs for a given padata object by tracking
the CPU within the padata object. If the serial callback gets called on
the wrong CPU, defer invoking padata_reorder() via a kernel worker on
the CPU we're expected to run on.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The reorder timer function runs on the CPU where the timer interrupt was
handled which is not necessarily one of the CPUs of the 'pcpu' CPU mask
set.
Ensure the padata_reorder() callback runs on the correct CPU, which is
one in the 'pcpu' CPU mask set and, preferrably, the next expected one.
Do so by comparing the current CPU with the expected target CPU. If they
match, call padata_reorder() right away. If they differ, schedule a work
item on the target CPU that does the padata_reorder() call for us.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The parallel queue per-cpu data structure gets initialized only for CPUs
in the 'pcpu' CPU mask set. This is not sufficient as the reorder timer
may run on a different CPU and might wrongly decide it's the target CPU
for the next reorder item as per-cpu memory gets memset(0) and we might
be waiting for the first CPU in cpumask.pcpu, i.e. cpu_index 0.
Make the '__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index'
compare in padata_get_next() fail in this case by initializing the
cpu_index member of all per-cpu parallel queues. Use -1 for unused ones.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In 32-bit mode, the x86 architecture can hold full 32-bit pointers.
Therefore, the code that copies the current address to the %ecx register
and uses %ecx-relative addressing is useless, we could just use absolute
addressing.
The processors have a stack of return addresses for branch prediction. If
we use a call instruction and pop the return address, it desynchronizes
the return stack and causes branch prediction misses.
This patch also moves the data to the .rodata section.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Use the provided mechanism in dmaengine.h to invoke the
completion callback.
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Clean up the mapped pages and the unmap object once we are done with
it. This enables the final clean-up of the object once the transfer
is complete.
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull x86 fixes from Thomas Gleixner:
"This contains the following fixes and improvements:
- Avoid dereferencing an unprotected VMA pointer in the fault signal
generation code
- Fix inline asm call constraints for GCC 4.4
- Use existing register variable to retrieve the stack pointer
instead of forcing the compiler to create another indirect access
which results in excessive extra 'mov %rsp, %<dst>' instructions
- Disable branch profiling for the memory encryption code to prevent
an early boot crash
- Fix a sparse warning caused by casting the __user annotation in
__get_user_asm_u64() away
- Fix an off by one error in the loop termination of the error patch
in the x86 sysfs init code
- Add missing CPU IDs to various Intel specific drivers to enable the
functionality on recent hardware
- More (init) constification in the numachip code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Use register variable to get stack pointer value
x86/mm: Disable branch profiling in mem_encrypt.c
x86/asm: Fix inline asm call constraints for GCC 4.4
perf/x86/intel/uncore: Correct num_boxes for IIO and IRP
perf/x86/intel/rapl: Add missing CPU IDs
perf/x86/msr: Add missing CPU IDs
perf/x86/intel/cstate: Add missing CPU IDs
x86: Don't cast away the __user in __get_user_asm_u64()
x86/sysfs: Fix off-by-one error in loop termination
x86/mm: Fix fault error path using unsafe vma pointer
x86/numachip: Add const and __initconst to numachip2_clockevent
Pull timer fixes from Thomas Gleixner:
"This adds a new timer wheel function which is required for the
conversion of the timer callback function from the 'unsigned long
data' argument to 'struct timer_list *timer'. This conversion has two
benefits:
1) It makes struct timer_list smaller
2) Many callers hand in a pointer to the timer or to the structure
containing the timer, which happens via type casting both at setup
and in the callback. This change gets rid of the typecasts.
Once the conversion is complete, which is planned for 4.15, the old
setup function and the intermediate typecast in the new setup function
go away along with the data field in struct timer_list.
Merging this now into mainline allows a smooth queueing of the actual
conversion in the affected maintainer trees without creating
dependencies"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
um/time: Fixup namespace collision
timer: Prepare to change timer callback argument type
Pull smp/hotplug fixes from Thomas Gleixner:
"This addresses the fallout of the new lockdep mechanism which covers
completions in the CPU hotplug code.
The lockdep splats are false positives, but there is no way to
annotate that reliably. The solution is to split the completions for
CPU up and down, which requires some reshuffling of the failure
rollback handling as well"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp/hotplug: Hotplug state fail injection
smp/hotplug: Differentiate the AP completion between up and down
smp/hotplug: Differentiate the AP-work lockdep class between up and down
smp/hotplug: Callback vs state-machine consistency
smp/hotplug: Rewrite AP state machine core
smp/hotplug: Allow external multi-instance rollback
smp/hotplug: Add state diagram
Pull scheduler fixes from Thomas Gleixner:
"The scheduler pull request comes with the following updates:
- Prevent a divide by zero issue by validating the input value of
sysctl_sched_time_avg
- Make task state printing consistent all over the place and have
explicit state characters for IDLE and PARKED so they wont be
displayed as 'D' state which confuses tools"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/sysctl: Check user input value of sysctl_sched_time_avg
sched/debug: Add explicit TASK_PARKED printing
sched/debug: Ignore TASK_IDLE for SysRq-W
sched/debug: Add explicit TASK_IDLE printing
sched/tracing: Use common task-state helpers
sched/tracing: Fix trace_sched_switch task-state printing
sched/debug: Remove unused variable
sched/debug: Convert TASK_state to hex
sched/debug: Implement consistent task-state printing
Pull perf fixes from Thomas Gleixner:
- Prevent a division by zero in the perf aux buffer handling
- Sync kernel headers with perf tool headers
- Fix a build failure in the syscalltbl code
- Make the debug messages of perf report --call-graph work correctly
- Make sure that all required perf files are in the MANIFEST for
container builds
- Fix the atrr.exclude kernel handling so it respects the
perf_event_paranoid and the user permissions
- Make perf test on s390x work correctly
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/aux: Only update ->aux_wakeup in non-overwrite mode
perf test: Fix vmlinux failure on s390x part 2
perf test: Fix vmlinux failure on s390x
perf tools: Fix syscalltbl build failure
perf report: Fix debug messages with --call-graph option
perf evsel: Fix attr.exclude_kernel setting for default cycles:p
tools include: Sync kernel ABI headers with tooling headers
perf tools: Get all of tools/{arch,include}/ in the MANIFEST
Pull locking fixes from Thomas Gleixner:
"Two fixes for locking:
- Plug a hole the pi_stat->owner serialization which was changed
recently and failed to fixup two usage sites.
- Prevent reordering of the rwsem_has_spinner() check vs the
decrement of rwsem count in up_write() which causes a missed
wakeup"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rwsem-xadd: Fix missed wakeup due to reordering of load
futex: Fix pi_state->owner serialization
Pull irq fixes from Thomas Gleixner:
- Add a missing NULL pointer check in free_irq()
- Fix a memory leak/memory corruption in the generic irq chip
- Add missing rcu annotations for radix tree access
- Use ffs instead of fls when extracting data from a chip register in
the MIPS GIC irq driver
- Fix the unmasking of IPI interrupts in the MIPS GIC driver so they
end up at the target CPU and not at CPU0
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq/generic-chip: Don't replace domain's name
irqdomain: Add __rcu annotations to radix tree accessors
irqchip/mips-gic: Use effective affinity to unmask
irqchip/mips-gic: Fix shifts to extract register fields
genirq: Check __free_irq() return value for NULL
Pull objtool fixes from Thomas Gleixner:
"Two small fixes for objtool:
- Support frame pointer setup via 'lea (%rsp), %rbp' which was not
yet supported and caused build warnings
- Disable unreacahble warnings for GCC4.4 and older to avoid false
positives caused by the compiler itself"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Support unoptimized frame pointer setup
objtool: Skip unreachable warnings for GCC 4.4 and older
