A subtle bug sneaked into iSeries recently. On this platform, we must
not normally clear MSR:EE (the hardware external interrupt enable)
except for short periods of time. Taking an interrupt while
soft-disabled doesn't cause us to clear it for example.
The iSeries kernel expects to mostly run with MSR:EE enabled at all
times except in a few exception entry/exit code paths. Thus
local_irq_enable() doesn't check if it needs to hard-enable as it
expects this to be unnecessary on iSeries.
However, hard_irq_disable() _does_ cause MSR:EE to be cleared,
including on iSeries. A call to it was recently added to the
context switch code, thus causing interrupts to become disabled
for a long periods of time, causing the iSeries watchdog to kick
in under some circumstances and other nasty things.
This patch fixes it by making local_irq_enable() properly re-enable
MSR:EE on iSeries. It basically removes a return statement here
to make iSeries use the same code path as everybody else. That does
mean that we might occasionally get spurious decrementer interrupts
but I don't think that matters.
Another option would have been to make hard_irq_disable() a nop
on iSeries but I didn't like it much, in case we have good reasons
to hard-disable.
Part of the patch is fixes to make sure the hard_enabled PACA field
is properly set on iSeries as it used not to be before, since it
was mostly unused.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A missing break statement in a switch caused cpm2_clk_setup() to initialize
SCC2 instead of SCC1.
Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
as prescribed in Documentation/powerpc/booting-without-of.txt.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Due to chip constraint MPC837x USB DR module can only use
ULPI and serial PHY interfaces. The patch fixes the wrong
type in dts.
This patch fixes USB malfunctioning on the MPC837xE-RDB boards.
Similar patch has been already applied for the MDS boards:
commit 28b9588592
Author: Li Yang <leoli@freescale.com>
Date: Thu Mar 6 18:42:26 2008 +0800
[POWERPC] 83xx: Fix wrong USB phy type in mpc837xmds dts
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
I believe http://bugzilla.kernel.org/show_bug.cgi?id=10318 is a false
positive. There's no way in which networking will be using highmem pages
here, so it won't be taking the KM_USER0 kmap slot, so there's no point in
performing these checks.
Cc: Pawel Staszewski <pstaszewski@artcom.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Really sad. We lose almost all real-life coverage of the debug tests
with this patch. Now it will only report problems for the cases where
people actually end up using a HIGHMEM page, not when they just _might_
use one. - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a bug in the powerpc DABR (data access breakpoint) handling,
which can result in us missing breakpoints if several threads are trying
to break on the same address.
The circumstances are that do_page_fault() calls do_dabr(), this clears
the DABR (sets it to 0) and sets up the signal which will report to
userspace that the DABR was hit. The do_signal() code will restore the DABR
value on the way out to userspace.
If we reschedule before calling do_signal(), __switch_to() will check the
cached DABR value and compare it to the new thread's value, if they match
we don't set the DABR in hardware.
So if two threads have the same DABR value, and we schedule from one to
the other after taking the interrupt for the first thread hitting the DABR,
the second thread will run without the DABR set in hardware.
The cleanest fix is to move the cache update into set_dabr(), that way we
can't forget to do it.
Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Took some cycles to re-read the Lguest Journey end-to-end, fix some
rot and tighten some phrases.
Only comments change. No new jokes, but a couple of recycled old jokes.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Linus noticed a second bug and an uncleanliness:
- we'd return on any instruction fetch fault
- we'd use both the value of 16 and the PF_INSTR symbol which are
the same and make no sense
the cleanup nicely unifies this piece of logic.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'avr32-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6:
avr32: Fix bug in early resource allocation code
avr32: Build fix for CONFIG_BUG=n
avr32: Work around byteswap bug in gcc < 4.2
We need to set up the shared_info pointer once we've mapped the real
shared_info into its fixmap slot. That needs to happen once the general
pagetable setup has been done. Previously, the UP shared_info was set
up one in xen_start_kernel, but that was left pointing to the dummy
shared info. Unfortunately there's no really good place to do a later
setup of the shared_info in UP, so just do it once the pagetable setup
has been done.
[ Stable: needed in 2.6.24.x ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
xen_irq_enable_direct and xen_sysexit were using "andw $0x00ff,
XEN_vcpu_info_pending(vcpu)" to unmask events and test for pending ones
in one instuction.
Unfortunately, the pending flag must be modified with a locked operation
since it can be set by another CPU, and the unlocked form of this
operation was causing the pending flag to get lost, allowing the processor
to return to usermode with pending events and ultimately deadlock.
The simple fix would be to make it a locked operation, but that's rather
costly and unnecessary. The fix here is to split the mask-clearing and
pending-testing into two instructions; the interrupt window between
them is of no concern because either way pending or new events will
be processed.
This should fix lingering bugs in using direct vcpu structure access too.
[ Stable: needed in 2.6.24.x ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The first page of the compound page is determined in follow_huge_addr()
but then PageCompound() only checks if the page is part of a compound page.
PageHead() allows checking if this is indeed the first page of the
compound.
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch fixes the use of GPIO routines which are in the PCI
configuration space of the RDC321x, therefore reading/writing
to this space without spinlock protection can be problematic.
We also now request and free GPIOs and support the MGB100
board, previous code was very AR525W-centric.
Signed-off-by: Volker Weiss <volker@tintuc.de>
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/ptrace.c:548: warning: 'ptrace_bts_get_size' defined but not used
arch/x86/kernel/ptrace.c:558: warning: 'ptrace_bts_read_record' defined but not used
arch/x86/kernel/ptrace.c:607: warning: 'ptrace_bts_clear' defined but not used
arch/x86/kernel/ptrace.c:617: warning: 'ptrace_bts_drain' defined but not used
arch/x86/kernel/ptrace.c:720: warning: 'ptrace_bts_config' defined but not used
arch/x86/kernel/ptrace.c:788: warning: 'ptrace_bts_status' defined but not used
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
some early Athlon XP's and Opterons generate bogus faults on prefetch
instructions. The workaround for this regressed over .24 - reinstate it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
add_reserved_region() tries to keep the resource list sorted, so when
looking for a place to insert the new resource, it may break out
before the last entry.
When this happens, the list is broken in two because the sibling field
of the new entry doesn't point to the next resource. Fix it by
updating the new resource's sibling field appropriately.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
fix the 3D performance drop reported at:
http://bugzilla.kernel.org/show_bug.cgi?id=10328
fb drivers are using ioremap()/ioremap_nocache(), followed by mtrr_add with
WC attribute. Recent changes in page attribute code made both
ioremap()/ioremap_nocache() mappings as UC (instead of previous UC-). This
breaks the graphics performance, as the effective memory type is UC instead
of expected WC.
The correct way to fix this is to add ioremap_wc() (which uses UC- in the
absence of PAT kernel support and WC with PAT) and change all the
fb drivers to use this new ioremap_wc() API.
We can take this correct and longer route for post 2.6.25. For now,
revert back to the UC- behavior for ioremap/ioremap_nocache.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
we could call find_max_pfn() directly instead of setup_memory() to get
max_pfn needed for mtrr trimming.
otherwise setup_memory() is called two times... that is duplicated...
[ mingo@elte.hu: both Thomas and me simulated a double call to
setup_bootmem_allocator() and can confirm that it is a real bug
which can hang in certain configs. It's not been reported yet but
that is probably due to the relatively scarce nature of
MTRR-trimming systems. ]
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On Wed, 26 Mar 2008 11:56:22 -0600
Jordan Crouse <jordan.crouse@amd.com> wrote:
> On 26/03/08 14:31 +0100, Stefan Pfetzing wrote:
> > Hello Jordan,
> >
> > I just tried to build your geodwdt driver for the geode watchdog. Therefore
> > I pulled your repository from http://git.infradead.org/geode.git (or more,
> > the git url).
> >
> > I tried to build the geodewdt driver as a module - which didn't work, and
> > it failed with the same problem as earlier mentioned on lkmk [1]. I also
> > checked the fix [2], but that seems to be already in your (or linus) tree -
> > and so I'm unsure what the problem is.
> >
> > [1] http://kerneltrap.org/mailarchive/linux-kernel/2008/2/17/884074
> > [2] http://kerneltrap.org/mailarchive/linux-kernel/2008/2/17/884174
> >
> > Building directly into the kernel seems to work.
> >
> > Maybe you have some idea?
>
> Hmm - that is strange. Exporting the symbols should work. I recommend
> starting over with a clean tree.
>
> CCing Andres - any thoughts?
>
> Jordan
>
Er, yeah. The patch below should fix it. This should probably go into
2.6.25.
Oops, EXPORT_SYMBOL_GPL wasn't being declared due to this header
being missing.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
I have found that using SMI to change the cpu's frequency on my DELL
Latitude L400 clobbers the ECX register in speedstep_set_state, causing
unneccessary retries because the "state" variable has changed silently (GCC
assumes it is still present in ECX).
play safe and avoid gcc caching any register across IO port accesses
that trigger SMIs.
Signed-off by: <Stephan.Diestelhorst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Convert function comment blocks to kernel-doc notation.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Sparse still doesn't like the funny cast we make from a scalar to a
"union semun" (which is correct by the C language and in particular
works with the sparc64 calling conventions, but sparse doesn't grok
that yet).
Signed-off-by: David S. Miller <davem@davemloft.net>
Add 'UL' markers to DCU_* macros.
Declare C functions called from assembler in entry.h
Declare C functions called from within the sparc64 arch
code in include/asm-sparc64/*.h headers as appropriate.
Remove unused routines in traps.c
Signed-off-by: David S. Miller <davem@davemloft.net>
IFF_ALLMULTI is an indication from the network stack to the driver
to disable multicast filters, drivers should never set it directly.
Since the UML networking device doesn't have any filtering capabilites,
it doesn't the set_multicast_list function at all, it is kept so userspace
can still issue SIOCADDMULTI/SIOCDELMULTI ioctls however.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
We create a local header file entry.h, under arch/sparc64/kernel/,
that we can use to declare routines either defined in assembler
or only invoked from assembler. As well as other data objects
which are private to the inner sparc64 kernel arch code.
Signed-off-by: David S. Miller <davem@davemloft.net>
Disable GEN_RTC since it conflicts with the i2c rtc drivers registering,
besides that keep most of the new defaults.
Signed-off-by: Olof Johansson <olof@lixom.net>
While backporting 72dc67a696, a gfn_to_page()
call was duplicated instead of moved (due to an unrelated patch not being
present in mainline). This caused a page reference leak, resulting in a
fairly massive memory leak.
Fix by removing the extraneous gfn_to_page() call.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Do not assume that a shadow mapping will always point to the same host
frame number. Fixes crash with madvise(MADV_DONTNEED).
[avi: move after first printk(), add another printk()]
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>