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  1. 14 5月, 2011 10 次提交
  3. 13 5月, 2011 21 次提交
  5. 12 5月, 2011 9 次提交
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse · 6eaed0a4
      由 Linus Torvalds 提交于 
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: fix oops in revalidate when called with NULL nameidata
      6eaed0a4
    • L
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6 · 8043f4eb
      由 Linus Torvalds 提交于 
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc32: Fixed unaligned memory copying in function __csum_partial_copy_sparc_generic
  sparc32: fix sparcstation 5 boot
  sparc32: fix section mismatch warnings in apc, pmc and time_32
      8043f4eb
    • L
      Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm · 75c0b3b4
      由 Linus Torvalds 提交于 
      * 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 6870/1: The mandatory barrier rmb() must be a dsb() in for device accesses
  ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls
  ARM: 6890/1: memmap: only free allocated memmap entries when using SPARSEMEM
  ARM: zImage: the page table memory must be considered before relocation
  ARM: zImage: make sure not to relocate on top of the relocation code
  ARM: zImage: Fix bad SP address after relocating kernel
  ARM: zImage: make sure the stack is 64-bit aligned
  ARM: RiscPC: acornfb: fix section mismatches
  ARM: RiscPC: etherh: fix section mismatches
      75c0b3b4
    • L
      fbmem: make read/write/ioctl use the frame buffer at open time · c47747fd
      由 Linus Torvalds 提交于 
      read/write/ioctl on a fbcon file descriptor has traditionally used the
fbcon not when it was opened, but as it was at the time of the call.
That makes no sense, but the lack of sense is much more obvious now that
we properly ref-count the usage - it means that the ref-counting doesn't
actually protect operations we do on the frame buffer.

This changes it to look at the fb_info that we got at open time, but in
order to avoid using a frame buffer long after it has been unregistered,
we do verify that it is still current, and return -ENODEV if not.
Acked-by: NTim Gardner <tim.gardner@canonical.com>
Tested-by: NDaniel J Blueman <daniel.blueman@gmail.com>
Tested-by: NAnca Emanuel <anca.emanuel@gmail.com>
Cc: Bruno Prémont <bonbons@linux-vserver.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Andy Whitcroft <andy.whitcroft@canonical.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c47747fd
    • L
      fbcon: add lifetime refcount to opened frame buffers · 698b3682
      由 Linus Torvalds 提交于 
      This just adds the refcount and the new registration lock logic.  It
does not (for example) actually change the read/write/ioctl routines to
actually use the frame buffer that was opened: those function still end
up alway susing whatever the current frame buffer is at the time of the
call.

Without this, if something holds the frame buffer open over a
framebuffer switch, the close() operation after the switch will access a
fb_info that has been free'd by the unregistering of the old frame
buffer.

(The read/write/ioctl operations will normally not cause problems,
because they will - illogically - pick up the new fbcon instead.  But a
switch that happens just as one of those is going on might see problems
too, the window is just much smaller: one individual op rather than the
whole open-close sequence.)

This use-after-free is apparently fairly easily triggered by the Ubuntu
11.04 boot sequence.
Acked-by: NTim Gardner <tim.gardner@canonical.com>
Tested-by: NDaniel J Blueman <daniel.blueman@gmail.com>
Tested-by: NAnca Emanuel <anca.emanuel@gmail.com>
Cc: Bruno Prémont <bonbons@linux-vserver.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Andy Whitcroft <andy.whitcroft@canonical.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      698b3682
    • B
      sfc: Always map MCDI shared memory as uncacheable · 747df225
      由 Ben Hutchings 提交于 
      We enabled write-combining for memory-mapped registers in commit
65f0b417, but inhibited it for the
MCDI shared memory where this is not supported.  However,
write-combining mappings also allow read-reordering, which may also
be a problem.

I found that when an SFC9000-family controller is connected to an
Intel 3000 chipset, and write-combining is enabled, the controller
stops responding to PCIe read requests during driver initialisation
while the driver is polling for completion of an MCDI command.  This
results in an NMI and system hang.  Adding read memory barriers
between all reads to the shared memory area appears to reduce but not
eliminate the probability of this.

We have not yet established whether this is a bug in our BIU or in the
PCIe bridge.  For now, work around by mapping the shared memory area
separately.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
      747df225
    • C
      ARM: 6870/1: The mandatory barrier rmb() must be a dsb() in for device accesses · a904f5f9
      由 Catalin Marinas 提交于 
      Since mandatory barriers may be used (explicitly or implicitly via readl
etc.) to ensure the ordering between Device and Normal memory accesses,
a DMB is not enough. This patch converts it to a DSB.

Cc: Colin Cross <ccross@android.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      a904f5f9
    • A
      ARM: 6892/1: handle ptrace requests to change PC during interrupted system calls · 2af68df0
      由 Arnd Bergmann 提交于 
      GDB's interrupt.exp test cases currenly fail on ARM.  The problem is how do_signal
handled restarting interrupted system calls:

The entry.S assembler code determines that we come from a system call; and that
information is passed as "syscall" parameter to do_signal.  That routine then
calls get_signal_to_deliver [*] and if a signal is to be delivered, calls into
handle_signal.  If a system call is to be restarted either after the signal
handler returns, or if no handler is to be called in the first place, the PC
is updated after the get_signal_to_deliver call, either in handle_signal (if
we have a handler) or at the end of do_signal (otherwise).

Now the problem is that during [*], the call to get_signal_to_deliver, a ptrace
intercept may happen.  During this intercept, the debugger may change registers,
including the PC.  This is done by GDB if it wants to execute an "inferior call",
i.e. the execution of some code in the debugged program triggered by GDB.

To this purpose, GDB will save all registers, allocate a stack frame, set up
PC and arguments as appropriate for the call, and point the link register to
a dummy breakpoint instruction.  Once the process is restarted, it will execute
the call and then trap back to the debugger, at which point GDB will restore
all registers and continue original execution.

This generally works fine.  However, now consider what happens when GDB attempts
to do exactly that while the process was interrupted during execution of a to-be-
restarted system call:  do_signal is called with the syscall flag set; it calls
get_signal_to_deliver, at which point the debugger takes over and changes the PC
to point to a completely different place.  Now get_signal_to_deliver returns
without a signal to deliver; but now do_signal decides it should be restarting
a system call, and decrements the PC by 2 or 4 -- so it now points to 2 or 4
bytes before the function GDB wants to call -- which leads to a subsequent crash.

To fix this problem, two things need to be supported:
- do_signal must be able to recognize that get_signal_to_deliver changed the PC
  to a different location, and skip the restart-syscall sequence
- once the debugger has restored all registers at the end of the inferior call
  sequence, do_signal must recognize that *now* it needs to restart the pending
  system call, even though it was now entered from a breakpoint instead of an
  actual svc instruction

This set of issues is solved on other platforms, usually by one of two
mechanisms:

- The status information "do_signal is handling a system call that may need
  restarting" is itself carried in some register that can be accessed via
  ptrace.  This is e.g. on Intel the "orig_eax" register; on Sparc the kernel
  defines a magic extra bit in the flags register for this purpose.
  This allows GDB to manage that state: reset it when doing an inferior call,
  and restore it after the call is finished.

- On s390, do_signal transparently handles this problem without requiring
  GDB interaction, by performing system call restarting in the following
  way: first, adjust the PC as necessary for restarting the call.  Then,
  call get_signal_to_deliver; and finally just continue execution at the
  PC.  This way, if GDB does not change the PC, everything is as before.
  If GDB *does* change the PC, execution will simply continue there --
  and once GDB restores the PC it saved at that point, it will automatically
  point to the *restarted* system call.  (There is the minor twist how to
  handle system calls that do *not* need restarting -- do_signal will undo
  the PC change in this case, after get_signal_to_deliver has returned, and
  only if ptrace did not change the PC during that call.)

Because there does not appear to be any obvious register to carry the
syscall-restart information on ARM, we'd either have to introduce a new
artificial ptrace register just for that purpose, or else handle the issue
transparently like on s390.  The patch below implements the second option;
using this patch makes the interrupt.exp test cases pass on ARM, with no
regression in the GDB test suite otherwise.

Cc: patches@linaro.org
Signed-off-by: NUlrich Weigand <ulrich.weigand@linaro.org>
Signed-off-by: NArnd Bergmann <arnd.bergmann@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      2af68df0
    • W
      ARM: 6890/1: memmap: only free allocated memmap entries when using SPARSEMEM · 9af386c8
      由 Will Deacon 提交于 
      The SPARSEMEM code allocates memmap entries only for sections which are
present (i.e. those which contain some valid memory). The membank checks
in free_unused_memmap do not take this into account and can incorrectly
attempt to free memory which is not allocated, resulting in a BUG() in
the bootmem code.

However, if memory is configured as follows:

    |<----section---->|<----hole---->|<----section---->|
    +--------+--------+--------------+--------+--------+
    | bank 0 | unused |              | bank 1 | unused |
    +--------+--------+--------------+--------+--------+

where a bank only occupies part of a section, the memmap allocated for
the remainder of the section *can* be freed.

This patch modifies the checks in free_unused_memmap so that only valid
memmap entries are considered for removal.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      9af386c8