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  1. 01 5月, 2014 1 次提交
    • H
      x86-64, espfix: Don't leak bits 31:16 of %esp returning to 16-bit stack · 3891a04a
      由 H. Peter Anvin 提交于 
      The IRET instruction, when returning to a 16-bit segment, only
restores the bottom 16 bits of the user space stack pointer.  This
causes some 16-bit software to break, but it also leaks kernel state
to user space.  We have a software workaround for that ("espfix") for
the 32-bit kernel, but it relies on a nonzero stack segment base which
is not available in 64-bit mode.

In checkin:

    b3b42ac2 x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels

we "solved" this by forbidding 16-bit segments on 64-bit kernels, with
the logic that 16-bit support is crippled on 64-bit kernels anyway (no
V86 support), but it turns out that people are doing stuff like
running old Win16 binaries under Wine and expect it to work.

This works around this by creating percpu "ministacks", each of which
is mapped 2^16 times 64K apart.  When we detect that the return SS is
on the LDT, we copy the IRET frame to the ministack and use the
relevant alias to return to userspace.  The ministacks are mapped
readonly, so if IRET faults we promote #GP to #DF which is an IST
vector and thus has its own stack; we then do the fixup in the #DF
handler.

(Making #GP an IST exception would make the msr_safe functions unsafe
in NMI/MC context, and quite possibly have other effects.)

Special thanks to:

- Andy Lutomirski, for the suggestion of using very small stack slots
  and copy (as opposed to map) the IRET frame there, and for the
  suggestion to mark them readonly and let the fault promote to #DF.
- Konrad Wilk for paravirt fixup and testing.
- Borislav Petkov for testing help and useful comments.
Reported-by: NBrian Gerst <brgerst@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andrew Lutomriski <amluto@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dirk Hohndel <dirk@hohndel.org>
Cc: Arjan van de Ven <arjan.van.de.ven@intel.com>
Cc: comex <comexk@gmail.com>
Cc: Alexander van Heukelum <heukelum@fastmail.fm>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org> # consider after upstream merge
      3891a04a
  3. 26 4月, 2014 3 次提交
  5. 25 4月, 2014 9 次提交
  7. 24 4月, 2014 8 次提交
  9. 23 4月, 2014 10 次提交
  11. 22 4月, 2014 4 次提交
    • J
      locks: rename file-private locks to "open file description locks" · 0d3f7a2d
      由 Jeff Layton 提交于 
      File-private locks have been merged into Linux for v3.15, and *now*
people are commenting that the name and macro definitions for the new
file-private locks suck.

...and I can't even disagree. The names and command macros do suck.

We're going to have to live with these for a long time, so it's
important that we be happy with the names before we're stuck with them.
The consensus on the lists so far is that they should be rechristened as
"open file description locks".

The name isn't a big deal for the kernel, but the command macros are not
visually distinct enough from the traditional POSIX lock macros. The
glibc and documentation folks are recommending that we change them to
look like F_OFD_{GETLK|SETLK|SETLKW}. That lessens the chance that a
programmer will typo one of the commands wrong, and also makes it easier
to spot this difference when reading code.

This patch makes the following changes that I think are necessary before
v3.15 ships:

1) rename the command macros to their new names. These end up in the uapi
   headers and so are part of the external-facing API. It turns out that
   glibc doesn't actually use the fcntl.h uapi header, but it's hard to
   be sure that something else won't. Changing it now is safest.

2) make the the /proc/locks output display these as type "OFDLCK"

Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Carlos O'Donell <carlos@redhat.com>
Cc: Stefan Metzmacher <metze@samba.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Frank Filz <ffilzlnx@mindspring.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
      0d3f7a2d
    • S
      ARM: zynq: dt: Add I2C nodes to Zynq device tree · 0f6faa3f
      由 Soren Brinkmann 提交于 
      Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
      0f6faa3f
    • S
      ARM: zynq: DT: Add 'clock-latency' property · b2bf5d48
      由 Soren Brinkmann 提交于 
      Specify the 'clock-latency' property to avoid certain cpufreq governors
from refusing to work with the following error:
  ondemand governor failed, too long transition latency of HW, fallback to performance governor
Reported-by: NMike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: NMike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
      b2bf5d48
    • T
      ARM: OMAP2+: Fix oops for GPMC free · efe80723
      由 Tony Lindgren 提交于 
      If gpmc_cs_remap() fails we will get an error because we are calling
release_resource() on an uninitialized resource. Let's fix that by
checking the resource flags. And while at it, let's also make
gpmc_cs_delete_mem() use the res pointer that we already have to
avoid confusion.

Without this patch we can get the following error:

omap-gpmc 6e000000.gpmc: cannot remap GPMC CS 1 to 0x01000300
Unable to handle kernel NULL pointer dereference at virtual address 00000018
...
(gpmc_cs_free+0x94/0xc8)
(gpmc_probe_generic_child+0x178/0x1ec)
(gpmc_probe_dt+0x1bc/0x2cc)
(gpmc_probe+0x250/0x44c)
(platform_drv_probe+0x3c/0x6c)
(really_probe+0x74/0x208)
(driver_probe_device+0x34/0x50)
(bus_for_each_drv+0x60/0x8c)
(device_attach+0x80/0xa4)
(bus_probe_device+0x88/0xb0)
(device_add+0x320/0x450)
(of_platform_device_create_pdata+0x80/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
(pdata_quirks_init+0x30/0x48)
(customize_machine+0x20/0x48)
(do_one_initcall+0x2c/0x14c)
(do_basic_setup+0x98/0xd8)
(kernel_init_freeable+0x12c/0x1e0)
(kernel_init+0x8/0xf0)
(ret_from_fork+0x14/0x2c)
Code: e1a04000 e59f0070 eb195136 e5942010 (e5923018)

Cc: Pekon Gupta <pekon@ti.com>
Reviewed-by: NJavier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Ntony Lindgren <tony@atomide.com>
      efe80723
  13. 21 4月, 2014 3 次提交
    • A
      um: Memory corruption on startup · 0565103d
      由 Anton Ivanov 提交于 
      The reverse case of this race (you must msync before read) is
well known. This is the not so common one.

It can be triggered only on systems which do a lot of task
switching and only at UML startup. If you are starting 200+ UMLs
~ 0.5% will always die without this fix.
Signed-off-by: NAnton Ivanov <antivano@cisco.com>
[rw: minor whitespace fixes]
Signed-off-by: NRichard Weinberger <richard@nod.at>
      0565103d
    • A
      um: Missing pipe handling · 9fcb663b
      由 Anton Ivanov 提交于 
      UML does not handle sigpipe. As a result when running it under
expect or redirecting the IO from the console to an external program
it will crash if the program stops or exits.
Signed-off-by: NAnton Ivanov <antivano@cisco.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>
      9fcb663b
    • T
      uml: Simplify tempdir logic. · 0d71832e
      由 Tristan Schmelcher 提交于 
      Inferring the mount hierarchy correctly from /proc/mounts is hard when MS_MOVE
may have been used, and the previous code did it wrongly. This change simplifies
the logic to only require that /dev/shm be _on_ tmpfs (which can be checked
trivially with statfs) rather than that it be a _mountpoint_ of tmpfs, since
there isn't a compelling reason to be that strict. We also now check for tmpfs
on whatever directory we ultimately use so that the user is better informed.

This change also moves the more standard TMPDIR environment variable check ahead
of the others.

Applies to 3.12.
Signed-off-by: NTristan Schmelcher <tschmelcher@google.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>
      0d71832e
  15. 19 4月, 2014 2 次提交