Pull PCI changes (including maintainer change) from Jesse Barnes:
"This pull has some good cleanups from Bjorn and Yinghai, as well as
some more code from Yinghai to better handle resource re-allocation
when enabled.
There's also a new initcall_debug feature from Arjan which will print
out quirk timing information to help identify slow quirks for fixing
or refinement (Yinghai sent in a few patches to do just that once the
new debug code landed).
Beyond that, I'm handing off PCI maintainership to Bjorn Helgaas.
He's been a core PCI and Linux contributor for some time now, and has
kindly volunteered to take over. I just don't feel I have the time
for PCI review and work that it deserves lately (I've taken on some
other projects), and haven't been as responsive lately as I'd like, so
I approached Bjorn asking if he'd like to manage things. He's going
to give it a try, and I'm confident he'll do at least as well as I
have in keeping the tree managed, patches flowing, and keeping things
stable."
Fix up some fairly trivial conflicts due to other cleanups (mips device
resource fixup cleanups clashing with list handling cleanup, ppc iseries
removal clashing with pci_probe_only cleanup etc)
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci: (112 commits)
PCI: Bjorn gets PCI hotplug too
PCI: hand PCI maintenance over to Bjorn Helgaas
unicore32/PCI: move <asm-generic/pci-bridge.h> include to asm/pci.h
sparc/PCI: convert devtree and arch-probed bus addresses to resource
powerpc/PCI: allow reallocation on PA Semi
powerpc/PCI: convert devtree bus addresses to resource
powerpc/PCI: compute I/O space bus-to-resource offset consistently
arm/PCI: don't export pci_flags
PCI: fix bridge I/O window bus-to-resource conversion
x86/PCI: add spinlock held check to 'pcibios_fwaddrmap_lookup()'
PCI / PCIe: Introduce command line option to disable ARI
PCI: make acpihp use __pci_remove_bus_device instead
PCI: export __pci_remove_bus_device
PCI: Rename pci_remove_behind_bridge to pci_stop_and_remove_behind_bridge
PCI: Rename pci_remove_bus_device to pci_stop_and_remove_bus_device
PCI: print out PCI device info along with duration
PCI: Move "pci reassigndev resource alignment" out of quirks.c
PCI: Use class for quirk for usb host controller fixup
PCI: Use class for quirk for ti816x class fixup
PCI: Use class for quirk for intel e100 interrupt fixup
...
Here's the big serial and tty merge for the 3.4-rc1 tree.
There's loads of fixes and reworks in here from Jiri for the tty layer,
and a number of patches from Alan to help try to wrestle the vt layer
into a sane model.
Other than that, lots of driver updates and fixes, and other minor
stuff, all detailed in the shortlog.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull TTY/serial patches from Greg KH:
"tty and serial merge for 3.4-rc1
Here's the big serial and tty merge for the 3.4-rc1 tree.
There's loads of fixes and reworks in here from Jiri for the tty
layer, and a number of patches from Alan to help try to wrestle the vt
layer into a sane model.
Other than that, lots of driver updates and fixes, and other minor
stuff, all detailed in the shortlog."
* tag 'tty-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (132 commits)
serial: pxa: add clk_prepare/clk_unprepare calls
TTY: Wrong unicode value copied in con_set_unimap()
serial: PL011: clear pending interrupts
serial: bfin-uart: Don't access tty circular buffer in TX DMA interrupt after it is reset.
vt: NULL dereference in vt_do_kdsk_ioctl()
tty: serial: vt8500: fix annotations for probe/remove
serial: remove back and forth conversions in serial_out_sync
serial: use serial_port_in/out vs serial_in/out in 8250
serial: introduce generic port in/out helpers
serial: reduce number of indirections in 8250 code
serial: delete useless void casts in 8250.c
serial: make 8250's serial_in shareable to other drivers.
serial: delete last unused traces of pausing I/O in 8250
pch_uart: Add module parameter descriptions
pch_uart: Use existing default_baud in setup_console
pch_uart: Add user_uartclk parameter
pch_uart: Add Fish River Island II uart clock quirks
pch_uart: Use uartclk instead of base_baud
mpc5200b/uart: select more tolerant uart prescaler on low baudrates
tty: moxa: fix bit test in moxa_start()
...
Instead of digging a tty out of the tty_driver struct, which is not
defined to work, use tty_port properly. This includes proper tty
refcounting even though there is no possible race currently. But we
will need tty_port for tty buffers in the future anyway.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The timer is initialized too late. tty->open may fire an invalid
timer. So initialize the timer earlier using DEFINE_TIMER.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty->count test in the timer was racy. Let's remove the test and
properly delete the timer and wait for the body to finish using _sync
version of del_timer.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tell the PCI core about host bridge address translation so it can take
care of bus-to-resource conversion for us.
CC: linux-parisc@vger.kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The address limit is already set in flush_old_exec() so those calls to
set_fs(USER_DS) are redundant.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This converts the parisc clocksources to use clocksource_register_hz/khz
This is untested, so any assistance in testing would be appreciated!
CC: Kyle McMartin <kyle@mcmartin.ca>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.
Fix these broken references, sometimes by dropping the irrelevant text
they were part of.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
These were missed in commit f5b9409973 "All Arch: remove linkage
for sys_nfsservctl system call" due to them having no sys_ prefix
(presumably).
Cc: NeilBrown <neilb@suse.de>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: James Bottomley <James.Bottomley@hansenpartnership.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
[PARISC] wire up sendmmsg syscall
[PARISC] fix return type of __atomic64_add_return
[PARISC] Fix futex support
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes all the module loader hook implementations in the
architecture specific code where the functionality is the same as that
now provided by the recently added default hooks.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
32bit and 64bit on x86 are tested and working. The rest I have looked
at closely and I can't find any problems.
setns is an easy system call to wire up. It just takes two ints so I
don't expect any weird architecture porting problems.
While doing this I have noticed that we have some architectures that are
very slow to get new system calls. cris seems to be the slowest where
the last system calls wired up were preadv and pwritev. avr32 is weird
in that recvmmsg was wired up but never declared in unistd.h. frv is
behind with perf_event_open being the last syscall wired up. On h8300
the last system call wired up was epoll_wait. On m32r the last system
call wired up was fallocate. mn10300 has recvmmsg as the last system
call wired up. The rest seem to at least have syncfs wired up which was
new in the 2.6.39.
v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com>
v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com>
v4: Moved wiring up of the system call to another patch
v5: ported to v2.6.39-rc6
v6: rebased onto parisc-next and net-next to avoid syscall conflicts.
v7: ported to Linus's latest post 2.6.39 tree.
> arch/blackfin/include/asm/unistd.h | 3 ++-
> arch/blackfin/mach-common/entry.S | 1 +
Acked-by: Mike Frysinger <vapier@gentoo.org>
Oh - ia64 wiring looks good.
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: Unify input section names
percpu: Avoid extra NOP in percpu_cmpxchg16b_double
percpu: Cast away printk format warning
percpu: Always align percpu output section to PAGE_SIZE
Fix up fairly trivial conflict in arch/x86/include/asm/percpu.h as per Tejun
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
[PARISC] wire up syncfs syscall
[PARISC] wire up the fhandle syscalls
[PARISC] wire up clock_adjtime syscall
[PARISC] wire up fanotify syscalls
[PARISC] prevent speculative re-read on cache flush
[PARISC] only make executable areas executable
[PARISC] fix pacache .size with new binutils
A new utility function (core_kernel_data()) is used to determine if a
passed in address is part of core kernel data or not. It may or may not
return true for RO data, but this utility must work for RW data.
Thus both _sdata and _edata must be defined and continuous,
without .init sections that may later be freed and replaced by
volatile memory (memory that can be freed).
This utility function is used to determine if data is safe from
ever being freed. Thus it should return true for all RW global
data that is not in a module or has been allocated, or false
otherwise.
Also change core_kernel_data() back to the more precise _sdata condition
and document the function.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Hirokazu Takata <takata@linux-m32r.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: JamesE.J.Bottomley <jejb@parisc-linux.org>
Link: http://lkml.kernel.org/r/1305855298.1465.19.camel@gandalf.stny.rr.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
----
arch/alpha/kernel/vmlinux.lds.S | 1 +
arch/m32r/kernel/vmlinux.lds.S | 1 +
arch/m68k/kernel/vmlinux-std.lds | 2 ++
arch/m68k/kernel/vmlinux-sun3.lds | 1 +
arch/mips/kernel/vmlinux.lds.S | 1 +
arch/parisc/kernel/vmlinux.lds.S | 3 +++
kernel/extable.c | 12 +++++++++++-
7 files changed, 20 insertions(+), 1 deletion(-)
According to Appendix F, the TLB is the primary arbiter of speculation.
Thus, if a page has a TLB entry, it may be speculatively read into the
cache. On linux, this can cause us incoherencies because if we're about
to do a disk read, we call get_user_pages() to do the flush/invalidate
in user space, but we still potentially have the user TLB entries, and
the cache could speculate the lines back into userspace (thus causing
stale data to be used). This is fixed by purging the TLB entries before
we flush through the tmpalias space. Now, the only way the line could
be re-speculated is if the user actually tries to touch it (which is not
allowed).
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Currently parisc has the whole kernel marked as RWX, meaning any
kernel page at all is eligible to be executed. This can cause a
theoretical problem on systems with combined I/D TLB because the act
of referencing a page causes a TLB insertion with an executable bit.
This TLB entry may be used by the CPU as the basis for speculating the
page into the I-Cache. If this speculated page is subsequently used
for a user process, there is the possibility we will get a stale
I-cache line picked up as the binary executes.
As a point of good practise, only mark actual kernel text pages as
executable. The same has to be done for init_text pages, but they're
converted to data pages (and the I-Cache flushed) when the init memory
is released.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Fix style of flush_user_dcache_range_asm procedure declaration in
arch/parisc/kernel/pacache.s to be consistent with other assembly
procedures.
Signed-off-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.
In order to do so we need a generic callback from the existing scheduler IPI.
This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.
BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
Convert to the new function names. Scripted with coccinelle.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: linux-parisc@vger.kernel.org
1) As promised in the comment, the core does not copy cpumask anymore
when the arch code returns -EINVAL
2) Get the per cpu information from irq_data
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: linux-parisc@vger.kernel.org
Percpu allocator honors alignment request upto PAGE_SIZE and both the
percpu addresses in the percpu address space and the translated kernel
addresses should be aligned accordingly. The calculation of the
former depends on the alignment of percpu output section in the kernel
image.
The linker script macros PERCPU_VADDR() and PERCPU() are used to
define this output section and the latter takes @align parameter.
Several architectures are using @align smaller than PAGE_SIZE breaking
percpu memory alignment.
This patch removes @align parameter from PERCPU(), renames it to
PERCPU_SECTION() and makes it always align to PAGE_SIZE. While at it,
add PCPU_SETUP_BUG_ON() checks such that alignment problems are
reliably detected and remove percpu alignment comment recently added
in workqueue.c as the condition would trigger BUG way before reaching
there.
For um, this patch raises the alignment of percpu area. As the area
is in .init, there shouldn't be any noticeable difference.
This problem was discovered by David Howells while debugging boot
failure on mn10300.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: user-mode-linux-devel@lists.sourceforge.net
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
[PARISC] Convert to new irq_chip functions
[PARISC] fix per-cpu flag problem in the cpu affinity checkers
[PARISC] fix vmap flush/invalidate
eliminate special FLUSH flag from page table
parisc: flush pages through tmpalias space
* 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu, x86: Add arch-specific this_cpu_cmpxchg_double() support
percpu: Generic support for this_cpu_cmpxchg_double()
alpha: use L1_CACHE_BYTES for cacheline size in the linker script
percpu: align percpu readmostly subsection to cacheline
Fix up trivial conflict in arch/x86/kernel/vmlinux.lds.S due to the
percpu alignment having changed ("x86: Reduce back the alignment of the
per-CPU data section")
Convert all the parisc driver interrupt handlers (dino, eisa, gsc,
iosapic and superio) as well as the cpu interrupts. Prepare
show_interrupts for GENERIC_HARDIRQS_NO_DEPRECATED and finally selects
that Kconfig option
[jejb: compile and testing fixes]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The CHECK_IRQ_PER_CPU is wrong, it should be checking
irq_to_desc(irq)->status not just irq.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The -rt patches change the console_semaphore to console_mutex. As a
result, a quite large chunk of the patches changes all
acquire/release_console_sem() to acquire/release_console_mutex()
This commit makes things use more neutral function names which dont make
implications about the underlying lock.
The only real change is the return value of console_trylock which is
inverted from try_acquire_console_sem()
This patch also paves the way to switching console_sem from a semaphore to
a mutex.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make console_trylock return 1 on success, per Geert]
Signed-off-by: Torben Hohn <torbenh@gmx.de>
Cc: Thomas Gleixner <tglx@tglx.de>
Cc: Greg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently percpu readmostly subsection may share cachelines with other
percpu subsections which may result in unnecessary cacheline bounce
and performance degradation.
This patch adds @cacheline parameter to PERCPU() and PERCPU_VADDR()
linker macros, makes each arch linker scripts specify its cacheline
size and use it to align percpu subsections.
This is based on Shaohua's x86 only patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shaohua.li@intel.com>
This was used to flush a region even if the page table entry had been
cleared. In theory this was never necessary, but now we've switched to
alias based flushing, the whole set of code associated with it can be dumped.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The kernel has an 8M tmpailas space (originally designed for copying
and clearing pages but now only used for clearing). The idea is
to place zeros into the cache above a physical page rather than into
the physical page and flush the cache, because often the zeros end up
being replaced quickly anyway.
We can also use the tmpalias space for flushing a page. The difference
here is that we have to do tmpalias processing in the non access data and
instruction traps. The principle is the same: as long as we know the physical
address and have a virtual address congruent to the real one, the flush will
be effective.
In order to use the tmpalias space, the icache miss path has to be enhanced to
check for the alias region to make the fic instruction effective.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Remove the broken line wrapping handling in pdc_iodc_print().
It is broken in 3 ways :
- It doesn't keep track of the current screen position, it just
assumes that the new buffer will be printed at the begining of the
screen.
- It doesn't take in account that non printable characters won't
increase the current position on the screen.
- And last but not least, it triggers a kernel panic if a backspace
is the first char in the provided buffer :
Backtrace:
[<0000000040128ec4>] pdc_console_write+0x44/0x78
[<0000000040128f18>] pdc_console_tty_write+0x20/0x38
[<000000004032f1ac>] n_tty_write+0x2a4/0x550
[<000000004032b158>] tty_write+0x1e0/0x2d8
[<00000000401bb420>] vfs_write+0xb8/0x188
[<00000000401bb630>] sys_write+0x68/0xb8
[<0000000040104eb8>] syscall_exit+0x0/0x14
Most terminals handle the line wrapping just fine. I've confirmed that
it works correctly on a C8000 with both vga and serial output.
Signed-off-by: Guy Martin <gmsoft@tuxicoman.be>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (36 commits)
serial: apbuart: Fixup apbuart_console_init()
TTY: Add tty ioctl to figure device node of the system console.
tty: add 'active' sysfs attribute to tty0 and console device
drivers: serial: apbuart: Handle OF failures gracefully
Serial: Avoid unbalanced IRQ wake disable during resume
tty: fix typos/errors in tty_driver.h comments
pch_uart : fix warnings for 64bit compile
8250: fix uninitialized FIFOs
ip2: fix compiler warning on ip2main_pci_tbl
specialix: fix compiler warning on specialix_pci_tbl
rocket: fix compiler warning on rocket_pci_ids
8250: add a UPIO_DWAPB32 for 32 bit accesses
8250: use container_of() instead of casting
serial: omap-serial: Add support for kernel debugger
serial: fix pch_uart kconfig & build
drivers: char: hvc: add arm JTAG DCC console support
RS485 documentation: add 16C950 UART description
serial: ifx6x60: fix memory leak
serial: ifx6x60: free IRQ on error
Serial: EG20T: add PCH_UART driver
...
Fixed up conflicts in drivers/serial/apbuart.c with evil merge that
makes the code look fairly sane (unlike either side).