linux.git/Documentation, branch v4.17.4

cxl: Disable prefault_mode in Radix mode

2018-07-03T09:26:52+00:00

commit b6c84ba22ff3a198eb8d5552cf9b8fda1d792e54 upstream.

Currently we see a kernel-oops reported on Power-9 while attaching a
context to an AFU, with radix-mode and sysfs attr 'prefault_mode' set
to anything other than 'none'. The backtrace of the oops is of this
form:

  Unable to handle kernel paging request for data at address 0x00000080
  Faulting instruction address: 0xc00800000bcf3b20
  cpu 0x1: Vector: 300 (Data Access) at [c00000037f003800]
      pc: c00800000bcf3b20: cxl_load_segment+0x178/0x290 [cxl]
      lr: c00800000bcf39f0: cxl_load_segment+0x48/0x290 [cxl]
      sp: c00000037f003a80
     msr: 9000000000009033
     dar: 80
   dsisr: 40000000
    current = 0xc00000037f280000
    paca    = 0xc0000003ffffe600   softe: 3        irq_happened: 0x01
      pid   = 3529, comm = afp_no_int
  
  cxl_prefault+0xfc/0x248 [cxl]
  process_element_entry_psl9+0xd8/0x1a0 [cxl]
  cxl_attach_dedicated_process_psl9+0x44/0x130 [cxl]
  native_attach_process+0xc0/0x130 [cxl]
  afu_ioctl+0x3f4/0x5e0 [cxl]
  do_vfs_ioctl+0xdc/0x890
  ksys_ioctl+0x68/0xf0
  sys_ioctl+0x40/0xa0
  system_call+0x58/0x6c

The issue is caused as on Power-8 the AFU attr 'prefault_mode' was
used to improve initial storage fault performance by prefaulting
process segments. However on Power-9 with radix mode we don't have
Storage-Segments that we can prefault. Also prefaulting process Pages
will be too costly and fine-grained.

Hence, since the prefaulting mechanism doesn't makes sense of
radix-mode, this patch updates prefault_mode_store() to not allow any
other value apart from CXL_PREFAULT_NONE when radix mode is enabled.

Fixes: f24be42aab37 ("cxl: Add psl9 specific code")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Vaibhav Jain 
Acked-by: Frederic Barrat 
Acked-by: Andrew Donnellan 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

lib/vsprintf: Remove atomic-unsafe support for %pCr

2018-07-03T09:26:48+00:00

commit 666902e42fd8344b923c02dc5b0f37948ff4f225 upstream.

"%pCr" formats the current rate of a clock, and calls clk_get_rate().
The latter obtains a mutex, hence it must not be called from atomic
context.

Remove support for this rarely-used format, as vsprintf() (and e.g.
printk()) must be callable from any context.

Any remaining out-of-tree users will start seeing the clock's name
printed instead of its rate.

Reported-by: Jia-Ju Bai 
Fixes: 900cca2944254edd ("lib/vsprintf: add %pC{,n,r} format specifiers for clocks")
Link: http://lkml.kernel.org/r/1527845302-12159-5-git-send-email-geert+renesas@glider.be
To: Jia-Ju Bai 
To: Jonathan Corbet 
To: Michael Turquette 
To: Stephen Boyd 
To: Zhang Rui 
To: Eduardo Valentin 
To: Eric Anholt 
To: Stefan Wahren 
To: Greg Kroah-Hartman 
Cc: Sergey Senozhatsky 
Cc: Petr Mladek 
Cc: Linus Torvalds 
Cc: Steven Rostedt 
Cc: linux-doc@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Geert Uytterhoeven 
Cc: stable@vger.kernel.org # 4.1+
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Petr Mladek 
Signed-off-by: Greg Kroah-Hartman

doc: fix sysfs ABI documentation

2018-06-16T07:18:22+00:00

commit f59acbc5e0f7f90452efd4c3318d5e5ec042c3e0 upstream.

In 4.9 kernel, the sysfs files for Hyper-V VMBus changed name but
the documentation files were not updated. The current sysfs file
names are /sys/bus/vmbus/devices//...

See commit 9a56e5d6a0ba ("Drivers: hv: make VMBus bus ids persistent")
and commit f6b2db084b65 ("vmbus: make sysfs names consistent with PCI")

Reported-by: Michael Kelley 
Signed-off-by: Stephen Hemminger 
Cc: stable@vger.kernel.org
Signed-off-by: K. Y. Srinivasan 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

netdev-FAQ: clarify DaveM's position for stable backports

2018-06-11T20:43:18+00:00

[ Upstream commit 75d4e704fa8d2cf33ff295e5b441317603d7f9fd ]

Per discussion with David at netconf 2018, let's clarify
DaveM's position of handling stable backports in netdev-FAQ.

This is important for people relying on upstream -stable
releases.

Cc: Greg Kroah-Hartman 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2018-06-03T00:35:53+00:00

Pull networking fixes from David Miller:

 1) Infinite loop in _decode_session6(), from Eric Dumazet.

 2) Pass correct argument to nla_strlcpy() in netfilter, also from Eric
    Dumazet.

 3) Out of bounds memory access in ipv6 srh code, from Mathieu Xhonneux.

 4) NULL deref in XDP_REDIRECT handling of tun driver, from Toshiaki
    Makita.

 5) Incorrect idr release in cls_flower, from Paul Blakey.

 6) Probe error handling fix in davinci_emac, from Dan Carpenter.

 7) Memory leak in XPS configuration, from Alexander Duyck.

 8) Use after free with cloned sockets in kcm, from Kirill Tkhai.

 9) MTU handling fixes fo ip_tunnel and ip6_tunnel, from Nicolas
    Dichtel.

10) Fix UAPI hole in bpf data structure for 32-bit compat applications,
    from Daniel Borkmann.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits)
  bpf: fix uapi hole for 32 bit compat applications
  net: usb: cdc_mbim: add flag FLAG_SEND_ZLP
  ip6_tunnel: remove magic mtu value 0xFFF8
  ip_tunnel: restore binding to ifaces with a large mtu
  net: dsa: b53: Add BCM5389 support
  kcm: Fix use-after-free caused by clonned sockets
  net-sysfs: Fix memory leak in XPS configuration
  ixgbe: fix parsing of TC actions for HW offload
  net: ethernet: davinci_emac: fix error handling in probe()
  net/ncsi: Fix array size in dumpit handler
  cls_flower: Fix incorrect idr release when failing to modify rule
  net/sonic: Use dma_mapping_error()
  xfrm Fix potential error pointer dereference in xfrm_bundle_create.
  vhost_net: flush batched heads before trying to busy polling
  tun: Fix NULL pointer dereference in XDP redirect
  be2net: Fix error detection logic for BE3
  net: qmi_wwan: Add Netgear Aircard 779S
  mlxsw: spectrum: Forbid creation of VLAN 1 over port/LAG
  atm: zatm: fix memcmp casting
  iwlwifi: pcie: compare with number of IRQs requested for, not number of CPUs
  ...

Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

2018-06-02T16:52:22+00:00

Pull i2c fixes from Wolfram Sang:
 "A documentation bugfix and a MAINTAINERS addition"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: ocores: update HDL sources URL
  i2c: xlp9xx: Add MAINTAINERS entry

net: dsa: b53: Add BCM5389 support

2018-06-01T15:15:42+00:00

This patch adds support for the BCM5389 switch connected through MDIO.

Signed-off-by: Damien Thébault 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller

i2c: ocores: update HDL sources URL

2018-05-29T18:14:32+00:00

The URL is broken. This patch fixes it.

Signed-off-by: Federico Vaga 
[wsa: shortened the URL a bit]
Signed-off-by: Wolfram Sang

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2018-05-26T02:54:42+00:00

Pull networking fixes from David Miller:
 "Let's begin the holiday weekend with some networking fixes:

   1) Whoops need to restrict cfg80211 wiphy names even more to 64
      bytes. From Eric Biggers.

   2) Fix flags being ignored when using kernel_connect() with SCTP,
      from Xin Long.

   3) Use after free in DCCP, from Alexey Kodanev.

   4) Need to check rhltable_init() return value in ipmr code, from Eric
      Dumazet.

   5) XDP handling fixes in virtio_net from Jason Wang.

   6) Missing RTA_TABLE in rtm_ipv4_policy[], from Roopa Prabhu.

   7) Need to use IRQ disabling spinlocks in mlx4_qp_lookup(), from Jack
      Morgenstein.

   8) Prevent out-of-bounds speculation using indexes in BPF, from
      Daniel Borkmann.

   9) Fix regression added by AF_PACKET link layer cure, from Willem de
      Bruijn.

  10) Correct ENIC dma mask, from Govindarajulu Varadarajan.

  11) Missing config options for PMTU tests, from Stefano Brivio"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (48 commits)
  ibmvnic: Fix partial success login retries
  selftests/net: Add missing config options for PMTU tests
  mlx4_core: allocate ICM memory in page size chunks
  enic: set DMA mask to 47 bit
  ppp: remove the PPPIOCDETACH ioctl
  ipv4: remove warning in ip_recv_error
  net : sched: cls_api: deal with egdev path only if needed
  vhost: synchronize IOTLB message with dev cleanup
  packet: fix reserve calculation
  net/mlx5: IPSec, Fix a race between concurrent sandbox QP commands
  net/mlx5e: When RXFCS is set, add FCS data into checksum calculation
  bpf: properly enforce index mask to prevent out-of-bounds speculation
  net/mlx4: Fix irq-unsafe spinlock usage
  net: phy: broadcom: Fix bcm_write_exp()
  net: phy: broadcom: Fix auxiliary control register reads
  net: ipv4: add missing RTA_TABLE to rtm_ipv4_policy
  net/mlx4: fix spelling mistake: "Inrerface" -> "Interface" and rephrase message
  ibmvnic: Only do H_EOI for mobility events
  tuntap: correctly set SOCKWQ_ASYNC_NOSPACE
  virtio-net: fix leaking page for gso packet during mergeable XDP
  ...

ppp: remove the PPPIOCDETACH ioctl

2018-05-25T02:55:07+00:00

The PPPIOCDETACH ioctl effectively tries to "close" the given ppp file
before f_count has reached 0, which is fundamentally a bad idea.  It
does check 'f_count < 2', which excludes concurrent operations on the
file since they would only be possible with a shared fd table, in which
case each fdget() would take a file reference.  However, it fails to
account for the fact that even with 'f_count == 1' the file can still be
linked into epoll instances.  As reported by syzbot, this can trivially
be used to cause a use-after-free.

Yet, the only known user of PPPIOCDETACH is pppd versions older than
ppp-2.4.2, which was released almost 15 years ago (November 2003).
Also, PPPIOCDETACH apparently stopped working reliably at around the
same time, when the f_count check was added to the kernel, e.g. see
https://lkml.org/lkml/2002/12/31/83.  Also, the current 'f_count < 2'
check makes PPPIOCDETACH only work in single-threaded applications; it
always fails if called from a multithreaded application.

All pppd versions released in the last 15 years just close() the file
descriptor instead.

Therefore, instead of hacking around this bug by exporting epoll
internals to modules, and probably missing other related bugs, just
remove the PPPIOCDETACH ioctl and see if anyone actually notices.  Leave
a stub in place that prints a one-time warning and returns EINVAL.

Reported-by: syzbot+16363c99d4134717c05b@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Biggers 
Acked-by: Paul Mackerras 
Reviewed-by: Guillaume Nault 
Tested-by: Guillaume Nault 
Signed-off-by: David S. Miller