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2015-08-06test_bpf: add module parameters to filter the tests to run.Nicolas Schichan1-0/+71
When developping on the interpreter or a particular JIT, it can be interesting to restrict the tests list to a specific test or a particular range of tests. This patch adds the following module parameters to the test_bpf module: * test_name=<string>: only the specified named test will be run. * test_id=<number>: only the test with the specified id will be run (see the output of test_bpf without parameters to get the test id). * test_range=<number>,<number>: only the tests within IDs in the specified id range are run (see the output of test_bpf without parameters to get the test ids). Any invalid range, test id or test name will result in -EINVAL being returned and no tests being run. Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-06test_bpf: test LD_ABS and LD_IND instructions on fragmented skbs.Nicolas Schichan1-0/+142
These new tests exercise various load sizes and offsets crossing the head/fragment boundary. Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-06test_bpf: allow tests to specify an skb fragment.Nicolas Schichan1-1/+38
This introduce a new test->aux flag (FLAG_SKB_FRAG) to tell the populate_skb() function to add a fragment to the test skb containing the data specified in test->frag_data). Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-06test_bpf: avoid oopsing the kernel when generate_test_data() fails.Nicolas Schichan1-0/+5
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-07lib/iommu-common.c: do not use 0xffffffffffffffffl for computing align_maskSowmini Varadhan1-1/+1
Using a 64 bit constant generates "warning: integer constant is too large for 'long' type" on 32 bit platforms. Instead use ~0ul and BITS_PER_LONG. Detected by Andrew Morton on ARMD. Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David S. Miller <davem@davemloft.net> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-05ASN.1: Handle 'ANY OPTIONAL' in grammarDavid Howells1-0/+8
An ANY object in an ASN.1 grammar that is marked OPTIONAL should be skipped if there is no more data to be had. This can be tested by editing X.509 certificates or PKCS#7 messages to remove the NULL from subobjects that look like the following: SEQUENCE { OBJECT(2a864886f70d01010b); NULL(); } This is an algorithm identifier plus an optional parameter. The modified DER can be passed to one of: keyctl padd asymmetric "" @s </tmp/modified.x509 keyctl padd pkcs7_test foo @s </tmp/modified.pkcs7 It should work okay with the patch and produce EBADMSG without. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
2015-08-05ASN.1: Fix non-match detection failure on data overrunDavid Howells1-3/+2
If the ASN.1 decoder is asked to parse a sequence of objects, non-optional matches get skipped if there's no more data to be had rather than a data-overrun error being reported. This is due to the code segment that decides whether to skip optional matches (ie. matches that could get ignored because an element is marked OPTIONAL in the grammar) due to a lack of data also skips non-optional elements if the data pointer has reached the end of the buffer. This can be tested with the data decoder for the new RSA akcipher algorithm that takes three non-optional integers. Currently, it skips the last integer if there is insufficient data. Without the fix, #defining DEBUG in asn1_decoder.c will show something like: next_op: pc=0/13 dp=0/270 C=0 J=0 - match? 30 30 00 - TAG: 30 266 CONS next_op: pc=2/13 dp=4/270 C=1 J=0 - match? 02 02 00 - TAG: 02 257 - LEAF: 257 next_op: pc=5/13 dp=265/270 C=1 J=0 - match? 02 02 00 - TAG: 02 3 - LEAF: 3 next_op: pc=8/13 dp=270/270 C=1 J=0 next_op: pc=11/13 dp=270/270 C=1 J=0 - end cons t=4 dp=270 l=270/270 The next_op line for pc=8/13 should be followed by a match line. This is not exploitable for X.509 certificates by means of shortening the message and fixing up the ASN.1 CONS tags because: (1) The relevant records being built up are cleared before use. (2) If the message is shortened sufficiently to remove the public key, the ASN.1 parse of the RSA key will fail quickly due to a lack of data. (3) Extracted signature data is either turned into MPIs (which cope with a 0 length) or is simpler integers specifying algoritms and suchlike (which can validly be 0); and (4) The AKID and SKID extensions are optional and their removal is handled without risking passing a NULL to asymmetric_key_generate_id(). (5) If the certificate is truncated sufficiently to remove the subject, issuer or serialNumber then the ASN.1 decoder will fail with a 'Cons stack underflow' return. This is not exploitable for PKCS#7 messages by means of removal of elements from such a message from the tail end of a sequence: (1) Any shortened X.509 certs embedded in the PKCS#7 message are survivable as detailed above. (2) The message digest content isn't used if it shows a NULL pointer, similarly, the authattrs aren't used if that shows a NULL pointer. (3) A missing signature results in a NULL MPI - which the MPI routines deal with. (4) If data is NULL, it is expected that the message has detached content and that is handled appropriately. (5) If the serialNumber is excised, the unconditional action associated with it will pick up the containing SEQUENCE instead, so no NULL pointer will be seen here. If both the issuer and the serialNumber are excised, the ASN.1 decode will fail with an 'Unexpected tag' return. In either case, there's no way to get to asymmetric_key_generate_id() with a NULL pointer. (6) Other fields are decoded to simple integers. Shortening the message to omit an algorithm ID field will cause checks on this to fail early in the verification process. This can also be tested by snipping objects off of the end of the ASN.1 stream such that mandatory tags are removed - or even from the end of internal SEQUENCEs. If any mandatory tag is missing, the error EBADMSG *should* be produced. Without this patch ERANGE or ENOPKG might be produced or the parse may apparently succeed, perhaps with ENOKEY or EKEYREJECTED being produced later, depending on what gets snipped. Just snipping off the final BIT_STRING or OCTET_STRING from either sample should be a start since both are mandatory and neither will cause an EBADMSG without the patches Reported-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
2015-08-05ASN.1: Fix actions on CHOICE elements with IMPLICIT tagsDavid Howells1-1/+13
In an ASN.1 description where there is a CHOICE construct that contains elements with IMPLICIT tags that refer to constructed types, actions to be taken on those elements should be conditional on the corresponding element actually being matched. Currently, however, such actions are performed unconditionally in the middle of processing the CHOICE. For example, look at elements 'b' and 'e' here: A ::= SEQUENCE { CHOICE { b [0] IMPLICIT B ({ do_XXXXXXXXXXXX_b }), c [1] EXPLICIT C ({ do_XXXXXXXXXXXX_c }), d [2] EXPLICIT B ({ do_XXXXXXXXXXXX_d }), e [3] IMPLICIT C ({ do_XXXXXXXXXXXX_e }), f [4] IMPLICIT INTEGER ({ do_XXXXXXXXXXXX_f }) } } ({ do_XXXXXXXXXXXX_A }) B ::= SET OF OBJECT IDENTIFIER ({ do_XXXXXXXXXXXX_oid }) C ::= SET OF INTEGER ({ do_XXXXXXXXXXXX_int }) They each have an action (do_XXXXXXXXXXXX_b and do_XXXXXXXXXXXX_e) that should only be processed if that element is matched. The problem is that there's no easy place to hang the action off in the subclause (type B for element 'b' and type C for element 'e') because subclause opcode sequences can be shared. To fix this, introduce a conditional action opcode(ASN1_OP_MAYBE_ACT) that the decoder only processes if the preceding match was successful. This can be seen in an excerpt from the output of the fixed ASN.1 compiler for the above ASN.1 description: [ 13] = ASN1_OP_COND_MATCH_JUMP_OR_SKIP, // e [ 14] = _tagn(CONT, CONS, 3), [ 15] = _jump_target(45), // --> C [ 16] = ASN1_OP_MAYBE_ACT, [ 17] = _action(ACT_do_XXXXXXXXXXXX_e), In this, if the op at [13] is matched (ie. element 'e' above) then the action at [16] will be performed. However, if the op at [13] doesn't match or is skipped because it is conditional and some previous op matched, then the action at [16] will be ignored. Note that to make this work in the decoder, the ASN1_OP_RETURN op must set the flag to indicate that a match happened. This is necessary because the _jump_target() seen above introduces a subclause (in this case an object of type 'C') which is likely to alter the flag. Setting the flag here is okay because to process a subclause, a match must have happened and caused a jump. This cannot be tested with the code as it stands, but rather affects future code. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
2015-08-05locking/static_keys: Make verify_keys() statickbuild test robot1-1/+1
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150803184748.GA80634@lkp-ib04 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-04Merge branches 'fixes.2015.07.22a' and 'initexp.2015.08.04a' into HEADPaul E. McKenney1-14/+0
fixes.2015.07.22a: Miscellaneous fixes. initexp.2015.08.04a: Initialization and expedited updates. (Single branch due to conflicts.)
2015-08-03locking/static_keys: Provide a selftestIngo Molnar5-235/+235
The 'jump label' self-test is in reality testing static keys - rename things accordingly. Also prettify the code in various places while at it. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: benh@kernel.crashing.org Cc: bp@alien8.de Cc: davem@davemloft.net Cc: ddaney@caviumnetworks.com Cc: heiko.carstens@de.ibm.com Cc: linux-kernel@vger.kernel.org Cc: liuj97@gmail.com Cc: luto@amacapital.net Cc: michael@ellerman.id.au Cc: rabin@rab.in Cc: ralf@linux-mips.org Cc: rostedt@goodmis.org Cc: vbabka@suse.cz Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/0c091ecebd78a879ed8a71835d205a691a75ab4e.1438227999.git.jbaron@akamai.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-03jump_label: Provide a self-testJason Baron4-0/+304
Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: benh@kernel.crashing.org Cc: bp@alien8.de Cc: davem@davemloft.net Cc: ddaney@caviumnetworks.com Cc: heiko.carstens@de.ibm.com Cc: linux-kernel@vger.kernel.org Cc: liuj97@gmail.com Cc: luto@amacapital.net Cc: michael@ellerman.id.au Cc: rabin@rab.in Cc: ralf@linux-mips.org Cc: rostedt@goodmis.org Cc: shuahkh@osg.samsung.com Cc: vbabka@suse.cz Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/0c091ecebd78a879ed8a71835d205a691a75ab4e.1438227999.git.jbaron@akamai.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-03Merge branch 'locking/urgent', tag 'v4.2-rc5' into locking/core, to pick up fixes before applying new changesIngo Molnar6-12/+16
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31Merge back earlier ACPI PM material for v4.3.Rafael J. Wysocki1-0/+41
2015-07-30test_bpf: assign type to native eBPF test casesDaniel Borkmann1-0/+2
As JITs start to perform optimizations whether to clear A and X on eBPF programs in the prologue, we should actually assign a program type to the native eBPF test cases. It doesn't really matter which program type, as these instructions don't go through the verifier, but it needs to be a type != BPF_PROG_TYPE_UNSPEC. This reflects eBPF programs loaded via bpf(2) system call (!= type unspec) vs. classic BPF to eBPF migrations (== type unspec). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29Merge branch 'acpi-scan' into acpi-pmRafael J. Wysocki1-2/+2
Conflicts: drivers/acpi/scan.c The conflict is resolved by moving the just introduced acpi_device_is_first_physical_node() to bus.c and using the existing acpi_companion_match() from there. There will be an additional commit to combine the two.
2015-07-28klist: implement klist_prev()Andy Shevchenko1-0/+41
klist_prev() gets the previous element in the list. It is useful to traverse through the list in reverse order, for example, to provide LIFO (last in first out) variant of access. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-07-27atomic: Add simple atomic_t testsPeter Zijlstra1-21/+47
Add a few atomic_t tests, gets some compile coverage for the new operations. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27atomic: Provide atomic_{or,xor,and}Peter Zijlstra1-0/+3
Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller4-6/+14
Conflicts: net/bridge/br_mdb.c br_mdb.c conflict was a function call being removed to fix a bug in 'net' but whose signature was changed in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-22rcu: Clarify CONFIG_RCU_EQS_DEBUG help textPaul E. McKenney1-1/+1
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-21rhashtable: Allow other tasks to be scheduled in large lookup loopsThomas Graf1-0/+7
Depending on system speed, the large lookup/insert/delete loops of the testsuite can take a considerable amount of time to complete causing watchdog warnings to appear. Allow other tasks to be scheduled throughout the loops. Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Thomas Graf <tgraf@suug.ch> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20test_bpf: add bpf_skb_vlan_push/pop() testsAlexei Starovoitov1-3/+95
improve accuracy of timing in test_bpf and add two stress tests: - {skb->data[0], get_smp_processor_id} repeated 2k times - {skb->data[0], vlan_push} x 68 followed by {skb->data[0], vlan_pop} x 68 1st test is useful to test performance of JIT implementation of BPF_LD_ABS together with BPF_CALL instructions. 2nd test is stressing skb_vlan_push/pop logic together with skb->data access via BPF_LD_ABS insn which checks that re-caching of skb->data is done correctly. In order to call bpf_skb_vlan_push() from test_bpf.ko have to add three export_symbol_gpl. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20lib/vsprintf.c: Include clk.hStephen Boyd1-0/+1
This file uses the clk API so it should include clk.h directly instead of indirectly including it through clk-provider.h. Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-20rtmutex: Delete scriptable testerDavidlohr Bueso1-6/+0
No one uses this anymore, and this is not the first time the idea of replacing it with a (now possible) userspace side. Lock stealing logic was removed long ago in when the lock was granted to the highest prio. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Darren Hart <dvhart@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1435782588-4177-2-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-20futex: Fault/error injection capabilitiesDavidlohr Bueso1-0/+7
Although futexes are well known for being a royal pita, we really have very little debugging capabilities - except for relying on tglx's eye half the time. By simply making use of the existing fault-injection machinery, we can improve this situation, allowing generating artificial uaddress faults and deadlock scenarios. Of course, when this is disabled in production systems, the overhead for failure checks is practically zero -- so this is very cheap at the same time. Future work would be nice to now enhance trinity to make use of this. There is a special tunable 'ignore-private', which can filter out private futexes. Given the tsk->make_it_fail filter and this option, pi futexes can be narrowed down pretty closely. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Darren Hart <darren@dvhart.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Link: http://lkml.kernel.org/r/1435645562-975-3-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-17lib/decompress: set the compressor name to NULL on errorAneesh Kumar K.V1-1/+4
Without this we end up using the previous name of the compressor in the loop in unpack_rootfs. For example we get errors like "compression method gzip not configured" even when we have CONFIG_DECOMPRESS_GZIP enabled. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17dma-debug: skip debug_dma_assert_idle() when disabledHaggai Eran1-0/+3
If dma-debug is disabled due to a memory error, DMA unmaps do not affect the dma_active_cacheline radix tree anymore, and debug_dma_assert_idle() can print false warnings. Disable debug_dma_assert_idle() when dma_debug_disabled() is true. Signed-off-by: Haggai Eran <haggaie@mellanox.com> Fixes: 0abdd7a81b7e ("dma-debug: introduce debug_dma_assert_idle()") Cc: Dan Williams <dan.j.williams@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: James Bottomley <JBottomley@Parallels.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Horia Geanta <horia.geanta@freescale.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17hexdump: fix for non-aligned buffersHoracio Mijail Anton Quiles1-3/+4
A hexdump with a buf not aligned to the groupsize causes non-naturally-aligned memory accesses. This was causing a kernel panic on the processor BlackFin BF527, when such an unaligned buffer was fed by the function ubifs_scanned_corruption in fs/ubifs/scan.c . To fix this, change accesses to the contents of the buffer so they go through get_unaligned(). This change should be harmless to unaligned- access-capable architectures, and any performance hit should be anyway dwarfed by the snprintf() processing time. Signed-off-by: Horacio Mijail Antón Quiles <hmijail@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: David Howells <dhowells@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Joe Perches <joe@perches.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17include, lib: add __printf attributes to several function prototypesNicolas Iooss1-2/+3
Using __printf attributes helps to detect several format string issues at compile time (even though -Wformat-security is currently disabled in Makefile). For example it can detect when formatting a pointer as a number, like the issue fixed in commit a3fa71c40f18 ("wl18xx: show rx_frames_per_rates as an array as it really is"), or when the arguments do not match the format string, c.f. for example commit 5ce1aca81435 ("reiserfs: fix __RASSERT format string"). To prevent similar bugs in the future, add a __printf attribute to every function prototype which needs one in include/linux/ and lib/. These functions were mostly found by using gcc's -Wsuggest-attribute=format flag. Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Felipe Balbi <balbi@ti.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17rcu: Remove CONFIG_RCU_CPU_STALL_INFOPaul E. McKenney1-14/+0
The CONFIG_RCU_CPU_STALL_INFO has been default-y for a couple of releases with no complaints, so it is time to eliminate this Kconfig option entirely, so that the long-form RCU CPU stall warnings cannot be disabled. This commit does just that. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17nmi: create generic NMI backtrace implementationRussell King2-1/+163
x86s NMI backtrace implementation (for arch_trigger_all_cpu_backtrace()) is fairly generic in nature - the only architecture specific bits are the act of raising the NMI to other CPUs, and reporting the status of the NMI handler. These are fairly simple to factor out, and produce a generic implementation which can be shared between ARM and x86. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller6-9/+46
Conflicts: net/bridge/br_mdb.c Minor conflict in br_mdb.c, in 'net' we added a memset of the on-stack 'ip' variable whereas in 'net-next' we assign a new member 'vid'. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds1-2/+2
Pull networking fixes from David Miller: 1) Missing list head init in bluetooth hidp session creation, from Tedd Ho-Jeong An. 2) Don't leak SKB in bridge netfilter error paths, from Florian Westphal. 3) ipv6 netdevice private leak in netfilter bridging, fixed by Julien Grall. 4) Fix regression in IP over hamradio bpq encapsulation, from Ralf Baechle. 5) Fix race between rhashtable resize events and table walks, from Phil Sutter. 6) Missing validation of IFLA_VF_INFO netlink attributes, fix from Daniel Borkmann. 7) Missing security layer socket state initialization in tipc code, from Stephen Smalley. 8) Fix shared IRQ handling in boomerang 3c59x interrupt handler, from Denys Vlasenko. 9) Missing minor_idr destroy on module unload on macvtap driver, from Johannes Thumshirn. 10) Various pktgen kernel thread races, from Oleg Nesterov. 11) Fix races that can cause packets to be processed in the backlog even after a device attached to that SKB has been fully unregistered. From Julian Anastasov. 12) bcmgenet driver doesn't account packet drops vs. errors properly, fix from Petri Gynther. 13) Array index validation and off by one fix in DSA layer from Florian Fainelli * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (66 commits) can: replace timestamp as unique skb attribute ARM: dts: dra7x-evm: Prevent glitch on DCAN1 pinmux can: c_can: Fix default pinmux glitch at init can: rcar_can: unify error messages can: rcar_can: print request_irq() error code can: rcar_can: fix typo in error message can: rcar_can: print signed IRQ # can: rcar_can: fix IRQ check net: dsa: Fix off-by-one in switch address parsing net: dsa: Test array index before use net: switchdev: don't abort unsupported operations net: bcmgenet: fix accounting of packet drops vs errors cdc_ncm: update specs URL Doc: z8530book: Fix typo in API-z8530-sync-txdma-open.html net: inet_diag: always export IPV6_V6ONLY sockopt for listening sockets bridge: mdb: allow the user to delete mdb entry if there's a querier net: call rcu_read_lock early in process_backlog net: do not process device backlog during unregistration bridge: fix potential crash in __netdev_pick_tx() net: axienet: Fix devm_ioremap_resource return value check ...
2015-07-08test_bpf: extend tests for 32-bit endianness conversionXi Wang1-0/+6
Currently "ALU_END_FROM_BE 32" and "ALU_END_FROM_LE 32" do not test if the upper bits of the result are zeros (the arm64 JIT had such bugs). Extend the two tests to catch this. Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-08rhashtable: fix for resize events during table walkPhil Sutter1-2/+2
If rhashtable_walk_next detects a resize operation in progress, it jumps to the new table and continues walking that one. But it misses to drop the reference to it's current item, leading it to continue traversing the new table's bucket in which the current item is sorted into, and after reaching that bucket's end continues traversing the new table's second bucket instead of the first one, thereby potentially missing items. This fixes the rhashtable runtime test for me. Bug probably introduced by Herbert Xu's patch eddee5ba ("rhashtable: Fix walker behaviour during rehash") although not explicitly tested. Fixes: eddee5ba ("rhashtable: Fix walker behaviour during rehash") Signed-off-by: Phil Sutter <phil@nwl.cc> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-06x86/kasan: Move KASAN_SHADOW_OFFSET to the arch KconfigAndrey Ryabinin1-4/+0
KASAN_SHADOW_OFFSET is purely arch specific setting, so it should be in arch's Kconfig file. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Cc: Alexander Popov <alpopov@ptsecurity.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1435828178-10975-7-git-send-email-a.ryabinin@samsung.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pendingLinus Torvalds1-3/+9
Pull SCSI target updates from Nicholas Bellinger: "It's been a busy development cycle for target-core in a number of different areas. The fabric API usage for se_node_acl allocation is now within target-core code, dropping the external API callers for all fabric drivers tree-wide. There is a new conversion to RCU hlists for se_node_acl and se_portal_group LUN mappings, that turns fast-past LUN lookup into a completely lockless code-path. It also removes the original hard-coded limitation of 256 LUNs per fabric endpoint. The configfs attributes for backends can now be shared between core and driver code, allowing existing drivers to use common code while still allowing flexibility for new backend provided attributes. The highlights include: - Merge sbc_verify_dif_* into common code (sagi) - Remove iscsi-target support for obsolete IFMarker/OFMarker (Christophe Vu-Brugier) - Add bidi support in target/user backend (ilias + vangelis + agover) - Move se_node_acl allocation into target-core code (hch) - Add crc_t10dif_update common helper (akinobu + mkp) - Handle target-core odd SGL mapping for data transfer memory (akinobu) - Move transport ID handling into target-core (hch) - Move task tag into struct se_cmd + support 64-bit tags (bart) - Convert se_node_acl->device_list[] to RCU hlist (nab + hch + paulmck) - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch + paulmck) - Simplify target backend driver registration (hch) - Consolidate + simplify target backend attribute implementations (hch + nab) - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch) - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab) - Drop unnecessary core_tpg_register TFO parameter (nab) - Use 64-bit LUNs tree-wide (hannes) - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits) target: Bump core version to v5.0 target: remove target_core_configfs.h target: remove unused TARGET_CORE_CONFIG_ROOT define target: consolidate version defines target: implement WRITE_SAME with UNMAP bit using ->execute_unmap target: simplify UNMAP handling target: replace se_cmd->execute_rw with a protocol_data field target/user: Fix inconsistent kmap_atomic/kunmap_atomic target: Send UA when changing LUN inventory target: Send UA upon LUN RESET tmr completion target: Send UA on ALUA target port group change target: Convert se_lun->lun_deve_lock to normal spinlock target: use 'se_dev_entry' when allocating UAs target: Remove 'ua_nacl' pointer from se_ua structure target_core_alua: Correct UA handling when switching states xen-scsiback: Fix compile warning for 64-bit LUN target: Remove TARGET_MAX_LUNS_PER_TRANSPORT target: use 64-bit LUNs target: Drop duplicate + unused se_dev_check_wce target: Drop unnecessary core_tpg_register TFO parameter ...
2015-07-04Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+5
Pull scheduler fixes from Ingo Molnar: "Debug info and other statistics fixes and related enhancements" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/numa: Fix numa balancing stats in /proc/pid/sched sched/numa: Show numa_group ID in /proc/sched_debug task listings sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y sched/stat: Simplify the sched_info accounting dependency
2015-07-04sched/stat: Simplify the sched_info accounting dependencyNaveen N. Rao1-0/+5
Both CONFIG_SCHEDSTATS=y and CONFIG_TASK_DELAY_ACCT=y track task sched_info, which results in ugly #if clauses. Simplify the code by introducing a synthethic CONFIG_SCHED_INFO switch, selected by both. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: a.p.zijlstra@chello.nl Cc: ricklind@us.ibm.com Link: http://lkml.kernel.org/r/8d19eef800811a94b0f91bcbeb27430a884d7433.1435255405.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-02Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuildLinus Torvalds2-0/+30
Pull kbuild updates from Michal Marek: "Just a few kbuild core commits this time: - kallsyms fix for CONFIG_XIP_KERNEL - bashisms in scripts/link-vmlinux.sh fixed - workaround to make DEBUG_INFO_REDUCED more useful yet still space efficient - clang is not wrongly detected when cross-compiling" * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kbuild: include core debug info when DEBUG_INFO_REDUCED scripts: link-vmlinux: Don't pass page offset to kallsyms if XIP Kernel scripts: fix link-vmlinux.sh bash-ism Makefile: Fix detection of clang when cross-compiling
2015-07-02Merge tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linuxLinus Torvalds1-1/+1
Pull module_init replacement part two from Paul Gortmaker: "Replace module_init with appropriate alternate initcall in non modules. This series converts non-modular code that is using the module_init() call to hook itself into the system to instead use one of our alternate priority initcalls. Unlike the previous series that used device_initcall and hence was a runtime no-op, these commits change to one of the alternate initcalls, because (a) we have them and (b) it seems like the right thing to do. For example, it would seem logical to use arch_initcall for arch specific setup code and fs_initcall for filesystem setup code. This does mean however, that changes in the init ordering will be taking place, and so there is a small risk that some kind of implicit init ordering issue may lie uncovered. But I think it is still better to give these ones sensible priorities than to just assign them all to device_initcall in order to exactly preserve the old ordering. Thad said, we have already made similar changes in core kernel code in commit c96d6660dc65 ("kernel: audit/fix non-modular users of module_init in core code") without any regressions reported, so this type of change isn't without precedent. It has also got the same local testing and linux-next coverage as all the other pull requests that I'm sending for this merge window have got. Once again, there is an unused module_exit function removal that shows up as an outlier upon casual inspection of the diffstat" * tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: x86: perf_event_intel_pt.c: use arch_initcall to hook in enabling x86: perf_event_intel_bts.c: use arch_initcall to hook in enabling mm/page_owner.c: use late_initcall to hook in enabling lib/list_sort: use late_initcall to hook in self tests arm: use subsys_initcall in non-modular pl320 IPC code powerpc: don't use module_init for non-modular core hugetlb code powerpc: use subsys_initcall for Freescale Local Bus x86: don't use module_init for non-modular core bootflag code netfilter: don't use module_init/exit in core IPV4 code fs/notify: don't use module_init for non-modular inotify_user code mm: replace module_init usages with subsys_initcall in nommu.c
2015-07-01Merge branch 'akpm' (patches from Andrew)Linus Torvalds2-16/+16
Merge third patchbomb from Andrew Morton: - the rest of MM - scripts/gdb updates - ipc/ updates - lib/ updates - MAINTAINERS updates - various other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits) genalloc: rename of_get_named_gen_pool() to of_gen_pool_get() genalloc: rename dev_get_gen_pool() to gen_pool_get() x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit MAINTAINERS: add zpool MAINTAINERS: BCACHE: Kent Overstreet has changed email address MAINTAINERS: move Jens Osterkamp to CREDITS MAINTAINERS: remove unused nbd.h pattern MAINTAINERS: update brcm gpio filename pattern MAINTAINERS: update brcm dts pattern MAINTAINERS: update sound soc intel patterns MAINTAINERS: remove website for paride MAINTAINERS: update Emulex ocrdma email addresses bcache: use kvfree() in various places libcxgbi: use kvfree() in cxgbi_free_big_mem() target: use kvfree() in session alloc and free IB/ehca: use kvfree() in ipz_queue_{cd}tor() drm/nouveau/gem: use kvfree() in u_free() drm: use kvfree() in drm_free_large() cxgb4: use kvfree() in t4_free_mem() cxgb3: use kvfree() in cxgb_free_mem() ...
2015-07-01Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linuxLinus Torvalds2-24/+59
Pull module updates from Rusty Russell: "Main excitement here is Peter Zijlstra's lockless rbtree optimization to speed module address lookup. He found some abusers of the module lock doing that too. A little bit of parameter work here too; including Dan Streetman's breaking up the big param mutex so writing a parameter can load another module (yeah, really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were appended too" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits) modules: only use mod->param_lock if CONFIG_MODULES param: fix module param locks when !CONFIG_SYSFS. rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE() module: add per-module param_lock module: make perm const params: suppress unused variable error, warn once just in case code changes. modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'. kernel/module.c: avoid ifdefs for sig_enforce declaration kernel/workqueue.c: remove ifdefs over wq_power_efficient kernel/params.c: export param_ops_bool_enable_only kernel/params.c: generalize bool_enable_only kernel/module.c: use generic module param operaters for sig_enforce kernel/params: constify struct kernel_param_ops uses sysfs: tightened sysfs permission checks module: Rework module_addr_{min,max} module: Use __module_address() for module_address_lookup() module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING module: Optimize __module_address() using a latched RB-tree rbtree: Implement generic latch_tree seqlock: Introduce raw_read_seqcount_latch() ...
2015-06-30Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfsLinus Torvalds1-0/+1
Pull btrfs updates from Chris Mason: "Outside of our usual batch of fixes, this integrates the subvolume quota updates that Qu Wenruo from Fujitsu has been working on for a few releases now. He gets an extra gold star for making btrfs smaller this time, and fixing a number of quota corners in the process. Dave Sterba tested and integrated Anand Jain's sysfs improvements. Outside of exporting a symbol (ack'd by Greg) these are all internal to btrfs and it's mostly cleanups and fixes. Anand also attached some of our sysfs objects to our internal device management structs instead of an object off the super block. It will make device management easier overall and it's a better fit for how the sysfs files are used. None of the existing sysfs files are moved around. Thanks for all the fixes everyone" * 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (87 commits) btrfs: delayed-ref: double free in btrfs_add_delayed_tree_ref() Btrfs: Check if kobject is initialized before put lib: export symbol kobject_move() Btrfs: sysfs: add support to show replacing target in the sysfs Btrfs: free the stale device Btrfs: use received_uuid of parent during send Btrfs: fix use-after-free in btrfs_replay_log btrfs: wait for delayed iputs on no space btrfs: qgroup: Make snapshot accounting work with new extent-oriented qgroup. btrfs: qgroup: Add the ability to skip given qgroup for old/new_roots. btrfs: ulist: Add ulist_del() function. btrfs: qgroup: Cleanup the old ref_node-oriented mechanism. btrfs: qgroup: Switch self test to extent-oriented qgroup mechanism. btrfs: qgroup: Switch to new extent-oriented qgroup mechanism. btrfs: qgroup: Switch rescan to new mechanism. btrfs: qgroup: Add new qgroup calculation function btrfs_qgroup_account_extents(). btrfs: backref: Add special time_seq == (u64)-1 case for btrfs_find_all_roots(). btrfs: qgroup: Add new function to record old_roots. btrfs: qgroup: Record possible quota-related extent for qgroup. btrfs: qgroup: Add function qgroup_update_counters(). ...
2015-06-30genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()Vladimir Zapolskiy1-3/+3
To be consistent with other kernel interface namings, rename of_get_named_gen_pool() to of_gen_pool_get(). In the original function name "_named" suffix references to a device tree property, which contains a phandle to a device and the corresponding device driver is assumed to register a gen_pool object. Due to a weak relation and to avoid any confusion (e.g. in future possible scenario if gen_pool objects are named) the suffix is removed. [sfr@canb.auug.org.au: crypto/marvell/cesa - fix up for of_get_named_gen_pool() rename] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Boris BREZILLON <boris.brezillon@free-electrons.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30genalloc: rename dev_get_gen_pool() to gen_pool_get()Vladimir Zapolskiy1-4/+4
To be consistent with other genalloc interface namings, rename dev_get_gen_pool() to gen_pool_get(). The original omitted "dev_" prefix is removed, since it points to argument type of the function, and so it does not bring any useful information. [akpm@linux-foundation.org: update arch/arm/mach-socfpga/pm.c] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Mark Brown <broonie@kernel.org> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Alan Tull <atull@opensource.altera.com> Cc: Dinh Nguyen <dinguyen@opensource.altera.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30drivers/scsi/scsi_debug.c: resolve sg buffer const-ness issueDave Gordon1-3/+3
do_device_access() takes a separate parameter to indicate the direction of data transfer, which it used to use to select the appropriate function out of sg_pcopy_{to,from}_buffer(). However these two functions now have So this patch makes it bypass these wrappers and call the underlying function sg_copy_buffer() directly; this has the same calling style as do_device_access() i.e. a separate direction-of-transfer parameter and no pointers-to-const, so skipping the wrappers not only eliminates the warning, it also make the code simpler :) [akpm@linux-foundation.org: fix very broken build] Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30lib/scatterlist: mark input buffer parameters as 'const'Dave Gordon1-4/+4
The 'buf' parameter of sg(p)copy_from_buffer() can and should be const-qualified, although because of the shared implementation of _to_buffer() and _from_buffer(), we have to cast this away internally. This means that callers who have a 'const' buffer containing the data to be copied to the sg-list no longer have to cast away the const-ness themselves. It also enables improved coverage by code analysis tools. Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30lib/scatterlist.c: fix kerneldoc for sg_pcopy_{to,from}_buffer()Dave Gordon1-2/+2
The kerneldoc for the functions doesn't match the code; the last two parameters (buflen, skip) have been transposed, which is confusing, especially as they're both integral types and the compiler won't warn about swapping them. These functions and the kerneldoc were introduced in commit: df642cea lib/scatterlist: introduce sg_pcopy_from_buffer() ... Author: Akinobu Mita <akinobu.mita@gmail.com> Date: Mon Jul 8 16:01:54 2013 -0700 The only difference between sg_pcopy_{from,to}_buffer() and sg_copy_{from,to}_buffer() is an additional argument that specifies the number of bytes to skip the SG list before copying. The functions have the extra argument at the end, but the kerneldoc lists it in penultimate position. Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>