Commit Graph

111658 Commits

Author SHA1 Message Date
Michael Holzheu 9db7f2b818 s390/bpf: recache skb->data/hlen for skb_vlan_push/pop
Allow eBPF programs attached to TC qdiscs call skb_vlan_push/pop
via helper functions. These functions may change skb->data/hlen.
This data is cached by s390 JIT to improve performance of ld_abs/ld_ind
instructions. Therefore after a change we have to reload the data.

In case of usage of skb_vlan_push/pop, in the prologue we store
the SKB pointer on the stack and restore it after BPF_JMP_CALL
to skb_vlan_push/pop.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 14:59:58 -07:00
Michael Holzheu cde66c2d88 s390/bpf: Only clear A and X for converted BPF programs
Only classic BPF programs that have been converted to eBPF need to clear
the A and X registers. We can check for converted programs with:

  bpf_prog->type == BPF_PROG_TYPE_UNSPEC

So add the check and skip initialization for real eBPF programs.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 14:59:58 -07:00
Michael Holzheu ce2b6ad9c1 s390/bpf: increase BPF_SIZE_MAX
Currently we have the restriction that jitted BPF programs can
have a maximum size of one page. The reason is that we use short
displacements for the literal pool.

The 20 bit displacements are available since z990 and BPF requires
z196 as minimum. Therefore we can remove this restriction and use
everywhere 20 bit signed long displacements.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 14:59:58 -07:00
Michael Holzheu 1df03ffdde s390/bpf: Fix multiple macro expansions
The EMIT6_DISP_LH macro passes the "disp" parameter to the _EMIT6_DISP_LH
macro. The _EMIT6_DISP_LH macro uses the "disp" parameter twice:

 unsigned int __disp_h = ((u32)disp) & 0xff000;
 unsigned int __disp_l = ((u32)disp) & 0x00fff;

The EMIT6_DISP_LH is used several times with EMIT_CONST_U64() as "disp"
parameter. Therefore always two constants are created per usage of
EMIT6_DISP_LH.

Fix this and add variable "_disp" to avoid multiple expansions.

* v2: Move "_disp" to _EMIT6_DISP_LH as suggested by Joe Perches

Fixes: 0546231057 ("s390/bpf: Add s390x eBPF JIT compiler backend")
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 14:59:58 -07:00
Michael Holzheu f75298f5c3 s390/bpf: clear correct BPF accumulator register
Currently we assumed the following BPF to eBPF register mapping:

 - BPF_REG_A -> BPF_REG_7
 - BPF_REG_X -> BPF_REG_8

Unfortunately this mapping is wrong. The correct mapping is:

 - BPF_REG_A -> BPF_REG_0
 - BPF_REG_X -> BPF_REG_7

So clear the correct registers and use the BPF_REG_A and BPF_REG_X
macros instead of BPF_REG_0/7.

Fixes: 0546231057 ("s390/bpf: Add s390x eBPF JIT compiler backend")
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 14:59:58 -07:00
Nicolas Schichan 5bf705b43b ARM: net: add support for BPF_ANC | SKF_AD_HATYPE in ARM JIT.
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 14:57:41 -07:00
Nicolas Schichan 303249ab16 ARM: net: add support for BPF_ANC | SKF_AD_PAY_OFFSET in ARM JIT.
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 14:57:40 -07:00
Nicolas Schichan 1447f93f22 ARM: net: add support for BPF_ANC | SKF_AD_PKTTYPE in ARM JIT.
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 14:57:40 -07:00
David S. Miller c5e40ee287 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
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>
2015-07-23 00:41:16 -07:00
Linus Torvalds c5dfd654d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Don't use shared bluetooth antenna in iwlwifi driver for management
    frames, from Emmanuel Grumbach.

 2) Fix device ID check in ath9k driver, from Felix Fietkau.

 3) Off by one in xen-netback BUG checks, from Dan Carpenter.

 4) Fix IFLA_VF_PORT netlink attribute validation, from Daniel Borkmann.

 5) Fix races in setting peeked bit flag in SKBs during datagram
    receive.  If it's shared we have to clone it otherwise the value can
    easily be corrupted.  Fix from Herbert Xu.

 6) Revert fec clock handling change, causes regressions.  From Fabio
    Estevam.

 7) Fix use after free in fq_codel and sfq packet schedulers, from WANG
    Cong.

 8) ipvlan bug fixes (memory leaks, missing rcu_dereference_bh, etc.)
    from WANG Cong and Konstantin Khlebnikov.

 9) Memory leak in act_bpf packet action, from Alexei Starovoitov.

10) ARM bpf JIT bug fixes from Nicolas Schichan.

11) Fix backwards compat of ANY_LAYOUT in virtio_net driver, from
    Michael S Tsirkin.

12) Destruction of bond with different ARP header types not handled
    correctly, fix from Nikolay Aleksandrov.

13) Revert GRO receive support in ipv6 SIT tunnel driver, causes
    regressions because the GRO packets created cannot be processed
    properly on the GSO side if we forward the frame.  From Herbert Xu.

14) TCCR update race and other fixes to ravb driver from Sergei
    Shtylyov.

15) Fix SKB leaks in caif_queue_rcv_skb(), from Eric Dumazet.

16) Fix panics on packet scheduler filter replace, from Daniel Borkmann.

17) Make sure AF_PACKET sees properly IP headers in defragmented frames
    (via PACKET_FANOUT_FLAG_DEFRAG option), from Edward Hyunkoo Jee.

18) AF_NETLINK cannot hold mutex in RCU callback, fix from Florian
    Westphal.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (84 commits)
  ravb: fix ring memory allocation
  net: phy: dp83867: Fix warning check for setting the internal delay
  openvswitch: allocate nr_node_ids flow_stats instead of num_possible_nodes
  netlink: don't hold mutex in rcu callback when releasing mmapd ring
  ARM: net: fix vlan access instructions in ARM JIT.
  ARM: net: handle negative offsets in BPF JIT.
  ARM: net: fix condition for load_order > 0 when translating load instructions.
  tcp: suppress a division by zero warning
  drivers: net: cpsw: remove tx event processing in rx napi poll
  inet: frags: fix defragmented packet's IP header for af_packet
  net: mvneta: fix refilling for Rx DMA buffers
  stmmac: fix setting of driver data in stmmac_dvr_probe
  sched: cls_flow: fix panic on filter replace
  sched: cls_flower: fix panic on filter replace
  sched: cls_bpf: fix panic on filter replace
  net/mdio: fix mdio_bus_match for c45 PHY
  net: ratelimit warnings about dst entry refcount underflow or overflow
  caif: fix leaks and race in caif_queue_rcv_skb()
  qmi_wwan: add the second QMI/network interface for Sierra Wireless MC7305/MC7355
  ravb: fix race updating TCCR
  ...
2015-07-22 14:45:25 -07:00
Linus Torvalds 5a5ca73ac0 - arm64 build fix following the move of the thread_struct to the end of
task_struct and the asm offsets becoming too large for the AArch64 ISA
 
 - preparatory patch for moving irq_data struct members (applied now to
   reduce dependency for the next merging window)
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull ARM64 fixes from Catalin Marinas:

 - arm64 build fix following the move of the thread_struct to the end of
   task_struct and the asm offsets becoming too large for the AArch64
   ISA

 - preparatory patch for moving irq_data struct members (applied now to
   reduce dependency for the next merging window)

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  ARM64/irq: Use access helper irq_data_get_affinity_mask()
  arm64: switch_to: calculate cpu context pointer using separate register
2015-07-22 08:52:42 -07:00
Jiang Liu 3bc38fc110 ARM64/irq: Use access helper irq_data_get_affinity_mask()
This is a preparatory patch for moving irq_data struct members.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-22 10:57:09 +01:00
Will Deacon c0d3fce5e1 arm64: switch_to: calculate cpu context pointer using separate register
Commit 0c8c0f03e3 ("x86/fpu, sched: Dynamically allocate 'struct fpu'")
moved the thread_struct to the bottom of task_struct. As a result, the
offset is now too large to be used in an immediate add on arm64 with
some kernel configs:

arch/arm64/kernel/entry.S: Assembler messages:
arch/arm64/kernel/entry.S:588: Error: immediate out of range
arch/arm64/kernel/entry.S:597: Error: immediate out of range

This patch calculates the offset using an additional register instead of
an immediate offset.

Fixes: 0c8c0f03e3 ("x86/fpu, sched: Dynamically allocate 'struct fpu'")
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-22 10:56:41 +01:00
Nicolas Schichan c18fe54b3f ARM: net: fix vlan access instructions in ARM JIT.
This makes BPF_ANC | SKF_AD_VLAN_TAG and BPF_ANC | SKF_AD_VLAN_TAG_PRESENT
have the same behaviour as the in kernel VM and makes the test_bpf LD_VLAN_TAG
and LD_VLAN_TAG_PRESENT tests pass.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 22:19:55 -07:00
Nicolas Schichan 6d715e301e ARM: net: handle negative offsets in BPF JIT.
Previously, the JIT would reject negative offsets known during code
generation and mishandle negative offsets provided at runtime.

Fix that by calling bpf_internal_load_pointer_neg_helper()
appropriately in the jit_get_skb_{b,h,w} slow path helpers and by forcing
the execution flow to the slow path helpers when the offset is
negative.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 22:19:55 -07:00
Nicolas Schichan 7aed35cb65 ARM: net: fix condition for load_order > 0 when translating load instructions.
To check whether the load should take the fast path or not, the code
would check that (r_skb_hlen - load_order) is greater than the offset
of the access using an "Unsigned higher or same" condition. For
halfword accesses and an skb length of 1 at offset 0, that test is
valid, as we end up comparing 0xffffffff(-1) and 0, so the fast path
is taken and the filter allows the load to wrongly succeed. A similar
issue exists for word loads at offset 0 and an skb length of less than
4.

Fix that by using the condition "Signed greater than or equal"
condition for the fast path code for load orders greater than 0.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 22:19:55 -07:00
Alexei Starovoitov 4e10df9a60 bpf: introduce bpf_skb_vlan_push/pop() helpers
Allow eBPF programs attached to TC qdiscs call skb_vlan_push/pop via
helper functions. These functions may change skb->data/hlen which are
cached by some JITs to improve performance of ld_abs/ld_ind instructions.
Therefore JITs need to recognize bpf_skb_vlan_push/pop() calls,
re-compute header len and re-cache skb->data/hlen back into cpu registers.
Note, skb->data/hlen are not directly accessible from the programs,
so any changes to skb->data done either by these helpers or by other
TC actions are safe.

eBPF JIT supported by three architectures:
- arm64 JIT is using bpf_load_pointer() without caching, so it's ok as-is.
- x64 JIT re-caches skb->data/hlen unconditionally after vlan_push/pop calls
  (experiments showed that conditional re-caching is slower).
- s390 JIT falls back to interpreter for now when bpf_skb_vlan_push() is present
  in the program (re-caching is tbd).

These helpers allow more scalable handling of vlan from the programs.
Instead of creating thousands of vlan netdevs on top of eth0 and attaching
TC+ingress+bpf to all of them, the program can be attached to eth0 directly
and manipulate vlans as necessary.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20 20:52:31 -07:00
Linus Torvalds 9d634c410b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fix from Martin Schwidefsky:
 "Fast path fix for the thread_struct breakage"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: adapt entry.S to the move of thread_struct
2015-07-20 12:18:40 -07:00
Martin Schwidefsky 3827ec3d8f s390: adapt entry.S to the move of thread_struct
git commit 0c8c0f03e3
"x86/fpu, sched: Dynamically allocate 'struct fpu'"
moved the thread_struct to the end of the task_struct.

This causes some of the offsets used in entry.S to overflow their
instruction operand field. To fix this  use aghi to create a
dedicated pointer for the thread_struct.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-07-20 13:22:18 +02:00
Viresh Kumar 09adcdf212 AVR32/time: Migrate to new 'set-state' interface
Migrate avr32 driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

We want to call cpu_idle_poll_ctrl() in shutdown only if we were in
oneshot or resume state earlier. Create another variable to save this
information and check that in shutdown callback.

Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
2015-07-20 12:19:10 +02:00
Linus Torvalds 8bff839927 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle:
 "Another round of MIPS fixes for 4.2.

  Things are looking quite decent at this stage but the recent work on
  the FPU support took its toll:

   - fix an incorrect overly restrictive ifdef

   - select O32 64-bit FP support for O32 binary compatibility

   - remove workarounds for Sibyte SB1250 Pass1 parts.  There are rare
     fixing the workarounds is not worth the effort.

   - patch up an outdated and now incorrect comment"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: fpu.h: Allow 64-bit FPU on a 64-bit MIPS R6 CPU
  MIPS: SB1: Remove support for Pass 1 parts.
  MIPS: Require O32 FP64 support for MIPS64 with O32 compat
  MIPS: asm-offset.c: Patch up various comments refering to the old filename.
2015-07-19 14:12:22 -07:00
Linus Torvalds ff72bf7adc Merge branch 'parisc-4.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fix from Helge Deller:
 "A memory leak fix from Christophe Jaillet which was introduced with
  kernel 4.0 and which leads to kernel crashes on parisc after 1-3 days"

* 'parisc-4.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: mm: Fix a memory leak related to pmd not attached to the pgd
2015-07-19 13:46:24 -07:00
Linus Torvalds 10b97f38a9 ARM: SoC fixes for v4.2
By far most of the fixes here are updates to DTS files to deal with some
 mostly minor bugs.
 
 There's also a fix to deal with non-PM kernel configs on i.MX, a
 regression fix for ethernet on PXA platforms and a dependency fix for OMAP.
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Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Olof Johansson:
 "By far most of the fixes here are updates to DTS files to deal with
  some mostly minor bugs.

  There's also a fix to deal with non-PM kernel configs on i.MX, a
  regression fix for ethernet on PXA platforms and a dependency fix for
  OMAP"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: keystone: dts: rename pcie nodes to help override status
  ARM: keystone: dts: fix dt bindings for PCIe
  ARM: pxa: fix dm9000 platform data regression
  ARM: dts: Correct audio input route & set mic bias for am335x-pepper
  ARM: OMAP2+: Add HAVE_ARM_SCU for AM43XX
  MAINTAINERS: digicolor: add dts files
  ARM: ux500: fix MMC/SD card regression
  ARM: ux500: define serial port aliases
  ARM: dts: OMAP5: Add #iommu-cells property to IOMMUs
  ARM: dts: OMAP4: Add #iommu-cells property to IOMMUs
  ARM: dts: Fix frequency scaling on Gumstix Pepper
  ARM: dts: configure regulators for Gumstix Pepper
  ARM: dts: omap3: overo: Update LCD panel names
  ARM: dts: cros-ec-keyboard: Add support for some Japanese keys
  ARM: imx6: gpc: always enable PU domain if CONFIG_PM is not set
  ARM: dts: imx53-qsb: fix TVE entry
  ARM: dts: mx23: fix iio-hwmon support
  ARM: dts: imx27: Adjust the GPT compatible string
  ARM: socfpga: dts: Fix entries order
  ARM: socfpga: dts: Fix adxl34x formating and compatible string
2015-07-19 13:37:44 -07:00
Markos Chandras fcc53b5f6c MIPS: fpu.h: Allow 64-bit FPU on a 64-bit MIPS R6 CPU
Commit 6134d94923 ("MIPS: asm: fpu: Allow 64-bit FPU on MIPS32 R6")
added support for 64-bit FPU on a 32-bit MIPS R6 processor but it missed
the 64-bit CPU case leading to FPU failures when requesting FR=1 mode
(which is always the case for MIPS R6 userland) when running a 32-bit
kernel on a 64-bit CPU. We also fix the MIPS R2 case.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Fixes: 6134d94923 ("MIPS: asm: fpu: Allow 64-bit FPU on MIPS32 R6")
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: <stable@vger.kernel.org> # 4.0+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10734/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-07-19 11:31:24 +02:00
Christophe Jaillet 4c4ac9a48a parisc: mm: Fix a memory leak related to pmd not attached to the pgd
Commit 0e0da48dee ("parisc: mm: don't count preallocated pmds")
introduced a memory leak.

After this commit, the 'return' statement in pmd_free is executed in all
cases. Even for pmd that are not attached to the pgd.  So 'free_pages'
can never be called anymore, leading to a memory leak.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org  # v4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
2015-07-19 08:56:14 +02:00
Olof Johansson 3eae03daa5 ARM: pxa: fixes for v4.2-rc2
This single fix reenables ethernet cards for several pxa boards,
 broken by regulator addition to dm9000 driver.
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Merge tag 'pxa-fixes-v4.2-rc2' of https://github.com/rjarzmik/linux into fixesD

Merge "pxa fixes for v4.2" from Robert Jarzmik:

ARM: pxa: fixes for v4.2-rc2

This single fix reenables ethernet cards for several pxa boards,
broken by regulator addition to dm9000 driver.

* tag 'pxa-fixes-v4.2-rc2' of https://github.com/rjarzmik/linux:
  ARM: pxa: fix dm9000 platform data regression
2015-07-18 21:06:10 -07:00
Linus Torvalds 9d37e6679d Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
 "A small set of ARM fixes for -rc3, most of them not far off
  one-liners, with the exception of fixing the V7 cache invalidation for
  incoming SMP processors which was causing problems for SoCFPGA
  devices"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: fix __virt_to_idmap build error on !MMU
  ARM: invalidate L1 before enabling coherency
  ARM: 8404/1: dma-mapping: fix off-by-one error in bitmap size check
  ARM: 8402/1: perf: Don't use of_node after putting it
  ARM: 8400/1: use virt_to_idmap to get phys_reset address
2015-07-18 11:03:48 -07:00
Linus Torvalds 0e1dbccd8f Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Two families of fixes:

   - Fix an FPU context related boot crash on newer x86 hardware with
     larger context sizes than what most people test.  To fix this
     without ugly kludges or extensive reverts we had to touch core task
     allocator, to allow x86 to determine the task size dynamically, at
     boot time.

     I've tested it on a number of x86 platforms, and I cross-built it
     to a handful of architectures:

                                        (warns)               (warns)
       testing     x86-64:  -git:  pass (    0),  -tip:  pass (    0)
       testing     x86-32:  -git:  pass (    0),  -tip:  pass (    0)
       testing        arm:  -git:  pass ( 1359),  -tip:  pass ( 1359)
       testing       cris:  -git:  pass ( 1031),  -tip:  pass ( 1031)
       testing       m32r:  -git:  pass ( 1135),  -tip:  pass ( 1135)
       testing       m68k:  -git:  pass ( 1471),  -tip:  pass ( 1471)
       testing       mips:  -git:  pass ( 1162),  -tip:  pass ( 1162)
       testing    mn10300:  -git:  pass ( 1058),  -tip:  pass ( 1058)
       testing     parisc:  -git:  pass ( 1846),  -tip:  pass ( 1846)
       testing      sparc:  -git:  pass ( 1185),  -tip:  pass ( 1185)

     ... so I hope the cross-arch impact 'none', as intended.

     (by Dave Hansen)

   - Fix various NMI handling related bugs unearthed by the big asm code
     rewrite and generally make the NMI code more robust and more
     maintainable while at it.  These changes are a bit late in the
     cycle, I hope they are still acceptable.

     (by Andy Lutomirski)"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86
  x86/fpu, sched: Dynamically allocate 'struct fpu'
  x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing code
  x86/nmi/64: Make the "NMI executing" variable more consistent
  x86/nmi/64: Minor asm simplification
  x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detection
  x86/nmi/64: Reorder nested NMI checks
  x86/nmi/64: Improve nested NMI comments
  x86/nmi/64: Switch stacks on userspace NMI entry
  x86/nmi/64: Remove asm code that saves CR2
  x86/nmi: Enable nested do_nmi() handling for 64-bit kernels
2015-07-18 10:49:57 -07:00
Linus Torvalds f79a17bf26 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, plus a static key fix fixing /sys/devices/cpu/rdpmc"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Really allow to specify custom CC, AR or LD
  perf auxtrace: Fix misplaced check for HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT
  perf hists browser: Take the --comm, --dsos, etc filters into account
  perf symbols: Store if there is a filter in place
  x86, perf: Fix static_key bug in load_mm_cr4()
  tools: Copy lib/hweight.c from the kernel sources
  perf tools: Fix the detached tarball wrt rbtree copy
  perf thread_map: Fix the sizeof() calculation for map entries
  tools lib: Improve clean target
  perf stat: Fix shadow declaration of close
  perf tools: Fix lockup using 32-bit compat vdso
2015-07-18 10:44:21 -07:00
Linus Torvalds 59ee762156 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
 "Misc irq fixes:

   - two driver fixes
   - a Xen regression fix
   - a nested irq thread crash fix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gicv3-its: Fix mapping of LPIs to collections
  genirq: Prevent resend to interrupts marked IRQ_NESTED_THREAD
  genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for now
  gpio/davinci: Fix race in installing chained irq handler
2015-07-18 10:27:12 -07:00
Ingo Molnar 5aaeb5c01c x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86
Don't burden architectures without dynamic task_struct sizing
with the overhead of dynamic sizing.

Also optimize the x86 code a bit by caching task_struct_size.

Acked-and-Tested-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.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>
Link: http://lkml.kernel.org/r/1437128892-9831-3-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-18 03:42:51 +02:00
Dave Hansen 0c8c0f03e3 x86/fpu, sched: Dynamically allocate 'struct fpu'
The FPU rewrite removed the dynamic allocations of 'struct fpu'.
But, this potentially wastes massive amounts of memory (2k per
task on systems that do not have AVX-512 for instance).

Instead of having a separate slab, this patch just appends the
space that we need to the 'task_struct' which we dynamically
allocate already.  This saves from doing an extra slab
allocation at fork().

The only real downside here is that we have to stick everything
and the end of the task_struct.  But, I think the
BUILD_BUG_ON()s I stuck in there should keep that from being too
fragile.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.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>
Link: http://lkml.kernel.org/r/1437128892-9831-2-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-18 03:42:35 +02:00
Laurent Dufour f2abeef9fd mm: clean up per architecture MM hook header files
Commit 2ae416b142 ("mm: new mm hook framework") introduced an empty
header file (mm-arch-hooks.h) for every architecture, even those which
doesn't need to define mm hooks.

As suggested by Geert Uytterhoeven, this could be cleaned through the use
of a generic header file included via each per architecture
asm/include/Kbuild file.

The PowerPC architecture is not impacted here since this architecture has
to defined the arch_remap MM hook.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:53 -07:00
Viresh Kumar da89947b47 Update Viresh Kumar's email address
Switch to my kernel.org alias instead of a badly named gmail address,
which I rarely use.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:53 -07:00
Dominik Dingel 7f9be77555 s390/hugetlb: add hugepages_supported define
On s390 we only can enable hugepages if the underlying hardware/hypervisor
also does support this.  Common code now would assume this to be
signaled by setting HPAGE_SHIFT to 0.  But on s390, where we only
support one hugepage size, there is a link between HPAGE_SHIFT and
pageblock_order.

So instead of setting HPAGE_SHIFT to 0, we will implement the check for
the hardware capability.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:52 -07:00
Dominik Dingel 41318bfe2a revert "s390/mm: make hugepages_supported a boot time decision"
Heiko noticed that the current check for hugepage support on s390 is a
little bit too harsh as systems which do not support will crash.

The reason is that pageblock_order can now get negative when we set
HPAGE_SHIFT to 0.  To avoid all this and to avoid opening another can of
worms with enabling HUGETLB_PAGE_SIZE_VARIABLE I think it would be best
to simply allow architectures to define their own hugepages_supported().

Revert bea41197ea ("s390/mm: make hugepages_supported a boot time
decision") in preparation.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:52 -07:00
Dominik Dingel ad4f99e888 revert "s390/mm: change HPAGE_SHIFT type to int"
Heiko noticed that the current check for hugepage support on s390 is a
little bit too harsh as systems which do not support will crash.

The reason is that pageblock_order can now get negative when we set
HPAGE_SHIFT to 0.  To avoid all this and to avoid opening another can of
worms with enabling HUGETLB_PAGE_SIZE_VARIABLE I think it would be best
to simply allow architectures to define their own hugepages_supported().

This patch (of 4): revert commit cf54e2fce5 ("s390/mm: change
HPAGE_SHIFT type to int") in preparation.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:52 -07:00
Andrew Morton 04ea1e91f8 openrisc: fix CONFIG_UID16 setting
openrisc-allnoconfig:

  kernel/uid16.c: In function 'SYSC_setgroups16':
  kernel/uid16.c:184:2: error: implicit declaration of function 'groups_alloc'
  kernel/uid16.c:184:13: warning: assignment makes pointer from integer without a cast

openrisc shouldn't be setting CONFIG_UID16 when CONFIG_MULTIUSER=n.

Fixes: 2813893f8b ("kernel: conditionally support non-root users, groups and capabilities")
Reported-by: Fengguang Wu <fengguang.wu@gmail.com>
Cc: Iulia Manda <iulia.manda21@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:52 -07:00
Olof Johansson 47295aa438 Couple of DTS fixes 4.2-rcx for Keystone EVMs:
K2E EVM boot hangs because of missing serdes driver which is needed to bring up
 PCIe on K2E. These couple of fixes makes the PCIE disabled on common default and
 let the specific board DTS to enable it.
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Merge tag 'keystone-dts-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into fixes

Merge "ARM: Couple of dts fixes for v4.2-rcx" from Santosh Shilimkar:

Couple of DTS fixes 4.2-rcx for Keystone EVMs:

K2E EVM boot hangs because of missing serdes driver which is needed to bring up
PCIe on K2E. These couple of fixes makes the PCIE disabled on common default and
let the specific board DTS to enable it.

* tag 'keystone-dts-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone:
  ARM: keystone: dts: rename pcie nodes to help override status
  ARM: keystone: dts: fix dt bindings for PCIe

Signed-off-by: Olof Johansson <olof@lixom.net>
2015-07-17 10:10:22 -07:00
Russell King 0871b72481 ARM: fix __virt_to_idmap build error on !MMU
Fengguang Wu reports that building ARM with !MMU results in the
following build error:

   arch/arm/kernel/built-in.o: In function `__soft_restart':
>> :(.text+0x1624): undefined reference to `arch_virt_to_idmap'

Fix this by adding an appropriate IS_ENABLED(CONFIG_MMU) into the
__virt_to_idmap() inline function.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17 15:08:40 +01:00
Russell King bac51ad9d1 ARM: invalidate L1 before enabling coherency
We must invalidate the L1 cache before enabling coherency, otherwise
secondary CPUs can inject invalid cache lines into the coherent CPU
cluster, which could then be migrated to other CPUs.  This fixes a
recent regression with SoCFPGA randomly failing to boot.

Fixes: 02b4e2756e ("ARM: v7 setup function should invalidate L1 cache")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17 15:08:40 +01:00
Marek Szyprowski 462859aa7b ARM: 8404/1: dma-mapping: fix off-by-one error in bitmap size check
nr_bitmaps member of mapping structure stores the number of already
allocated bitmaps and it is interpreted as loop iterator (it starts from
0 not from 1), so a comparison against number of possible bitmap
extensions should include this fact. This patch fixes this by changing
the extension failure condition. This issue has been introduced by
commit 4d852ef8c2 ("arm: dma-mapping: Add
support to extend DMA IOMMU mappings").

Reported-by: Hyungwon Hwang <human.hwang@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Hyungwon Hwang <human.hwang@samsung.com>
Cc: stable@vger.kernel.org  # v3.15+
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17 15:08:40 +01:00
Stephen Boyd 8e0c34b0d2 ARM: 8402/1: perf: Don't use of_node after putting it
It's possible, albeit unlikely, that using the of_node here will
reference freed memory. Call of_node_put() after printing the
name to be safe.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17 15:08:38 +01:00
Vitaly Andrianov df9de3c429 ARM: 8400/1: use virt_to_idmap to get phys_reset address
This patch is to get correct physical address of the reset function for
PAE systems, which use aliased physical memory for booting.

See the "ARM: mm: Introduce virt_to_idmap() with an arch hook" for details.

Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17 15:08:17 +01:00
Andy Lutomirski a97439aa1a x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing code
It turns out to be rather tedious to test the NMI nesting code.
Make it easier: add a new CONFIG_DEBUG_ENTRY option that causes
the NMI handler to pre-emptively unmask NMIs.

With this option set, errors in the repeat_nmi logic or failures
to detect that we're in a nested NMI will result in quick panics
under perf (especially if multiple counters are running at high
frequency) instead of requiring an unusual workload that
generates page faults or breakpoints inside NMIs.

I called it CONFIG_DEBUG_ENTRY instead of CONFIG_DEBUG_NMI_ENTRY
because I want to add new non-NMI checks elsewhere in the entry
code in the future, and I'd rather not add too many new config
options or add this option and then immediately rename it.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:14 +02:00
Andy Lutomirski 36f1a77b3a x86/nmi/64: Make the "NMI executing" variable more consistent
Currently, "NMI executing" is one the first time an outermost
NMI hits repeat_nmi and zero thereafter.  Change it to be zero
each time for consistency.

This is intended to help NMI handling fail harder if it's buggy.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:13 +02:00
Andy Lutomirski 23a781e987 x86/nmi/64: Minor asm simplification
Replace LEA; MOV with an equivalent SUB.  This saves one
instruction.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:13 +02:00
Andy Lutomirski 810bc075f7 x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detection
We have a tricky bug in the nested NMI code: if we see RSP
pointing to the NMI stack on NMI entry from kernel mode, we
assume that we are executing a nested NMI.

This isn't quite true.  A malicious userspace program can point
RSP at the NMI stack, issue SYSCALL, and arrange for an NMI to
happen while RSP is still pointing at the NMI stack.

Fix it with a sneaky trick.  Set DF in the region of code that
the RSP check is intended to detect.  IRET will clear DF
atomically.

( Note: other than paravirt, there's little need for all this
  complexity. We could check RIP instead of RSP. )

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:12 +02:00
Andy Lutomirski a27507ca2d x86/nmi/64: Reorder nested NMI checks
Check the repeat_nmi .. end_repeat_nmi special case first.  The
next patch will rework the RSP check and, as a side effect, the
RSP check will no longer detect repeat_nmi .. end_repeat_nmi, so
we'll need this ordering of the checks.

Note: this is more subtle than it appears.  The check for
repeat_nmi .. end_repeat_nmi jumps straight out of the NMI code
instead of adjusting the "iret" frame to force a repeat.  This
is necessary, because the code between repeat_nmi and
end_repeat_nmi sets "NMI executing" and then writes to the
"iret" frame itself.  If a nested NMI comes in and modifies the
"iret" frame while repeat_nmi is also modifying it, we'll end up
with garbage.  The old code got this right, as does the new
code, but the new code is a bit more explicit.

If we were to move the check right after the "NMI executing"
check, then we'd get it wrong and have random crashes.

( Because the "NMI executing" check would jump to the code that would
  modify the "iret" frame without checking if the interrupted NMI was
  currently modifying it. )

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:12 +02:00
Andy Lutomirski 0b22930eba x86/nmi/64: Improve nested NMI comments
I found the nested NMI documentation to be difficult to follow.
Improve the comments.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:11 +02:00