The kernel's implementation of notifier chains is unsafe. There is no
protection against entries being added to or removed from a chain while the
chain is in use. The issues were discussed in this thread:
http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2
We noticed that notifier chains in the kernel fall into two basic usage
classes:
"Blocking" chains are always called from a process context
and the callout routines are allowed to sleep;
"Atomic" chains can be called from an atomic context and
the callout routines are not allowed to sleep.
We decided to codify this distinction and make it part of the API. Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name). New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain. The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.
With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed. For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections. (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)
There are some limitations, which should not be too hard to live with. For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem. Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain. (This did happen in a couple of places and the code
had to be changed to avoid it.)
Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization. Instead we use RCU. The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.
Here is the list of chains that we adjusted and their classifications. None
of them use the raw API, so for the moment it is only a placeholder.
ATOMIC CHAINS
-------------
arch/i386/kernel/traps.c: i386die_chain
arch/ia64/kernel/traps.c: ia64die_chain
arch/powerpc/kernel/traps.c: powerpc_die_chain
arch/sparc64/kernel/traps.c: sparc64die_chain
arch/x86_64/kernel/traps.c: die_chain
drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list
kernel/panic.c: panic_notifier_list
kernel/profile.c: task_free_notifier
net/bluetooth/hci_core.c: hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain
net/ipv6/addrconf.c: inet6addr_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain
net/netlink/af_netlink.c: netlink_chain
BLOCKING CHAINS
---------------
arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain
arch/s390/kernel/process.c: idle_chain
arch/x86_64/kernel/process.c idle_notifier
drivers/base/memory.c: memory_chain
drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list
drivers/macintosh/adb.c: adb_client_list
drivers/macintosh/via-pmu.c sleep_notifier_list
drivers/macintosh/via-pmu68k.c sleep_notifier_list
drivers/macintosh/windfarm_core.c wf_client_list
drivers/usb/core/notify.c usb_notifier_list
drivers/video/fbmem.c fb_notifier_list
kernel/cpu.c cpu_chain
kernel/module.c module_notify_list
kernel/profile.c munmap_notifier
kernel/profile.c task_exit_notifier
kernel/sys.c reboot_notifier_list
net/core/dev.c netdev_chain
net/decnet/dn_dev.c: dnaddr_chain
net/ipv4/devinet.c: inetaddr_chain
It's possible that some of these classifications are wrong. If they are,
please let us know or submit a patch to fix them. Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)
The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.
[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Provide proper kprobes fault handling, if a user-specified pre/post handlers
tries to access user address space, through copy_from_user(), get_user() etc.
The user-specified fault handler gets called only if the fault occurs while
executing user-specified handlers. In such a case user-specified handler is
allowed to fix it first, later if the user-specifed fault handler does not fix
it, we try to fix it by calling fix_exception().
The user-specified handler will not be called if the fault happens when single
stepping the original instruction, instead we reset the current probe and
allow the system page fault handler to fix it up.
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently kprobe handler traps only happen in kernel space, so function
kprobe_exceptions_notify should skip traps which happen in user space.
This patch modifies this, and it is based on 2.6.16-rc4.
Signed-off-by: bibo mao <bibo.mao@intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Cc: <hiramatu@sdl.hitachi.co.jp>
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When kretprobe probes the schedule() function, if the probed process exits
then schedule() will never return, so some kretprobe instances will never
be recycled.
In this patch the parent process will recycle retprobe instances of the
probed function and there will be no memory leak of kretprobe instances.
Signed-off-by: bibo mao <bibo.mao@intel.com>
Cc: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create compat_sys_adjtimex and use it an all appropriate places.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We had a copy of the compatibility version of struct timex in each 64 bit
architecture. This patch just creates a global one and replaces all the
usages of the old ones.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Acked-by: Tony Luck <tony.luck@intel.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jens Axboe <axboe@suse.de>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: Greg KH <greg@kroah.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild: (46 commits)
kbuild: remove obsoleted scripts/reference_* files
kbuild: fix make help & make *pkg
kconfig: fix time ordering of writes to .kconfig.d and include/linux/autoconf.h
Kconfig: remove the CONFIG_CC_ALIGN_* options
kbuild: add -fverbose-asm to i386 Makefile
kbuild: clean-up genksyms
kbuild: Lindent genksyms.c
kbuild: fix genksyms build error
kbuild: in makefile.txt note that Makefile is preferred name for kbuild files
kbuild: replace PHONY with FORCE
kbuild: Fix bug in crc symbol generating of kernel and modules
kbuild: change kbuild to not rely on incorrect GNU make behavior
kbuild: when warning symbols exported twice now tell user this is the problem
kbuild: fix make dir/file.xx when asm symlink is missing
kbuild: in the section mismatch check try harder to find symbols
kbuild: fix section mismatch check for unwind on IA64
kbuild: kill false positives from section mismatch warnings for powerpc
kbuild: kill trailing whitespace in modpost & friends
kbuild: small update of allnoconfig description
kbuild: make namespace.pl CROSS_COMPILE happy
...
Trivial conflict in arch/ppc/boot/Makefile manually fixed up
When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all. The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().
This patch is a kernel-wide sweep of all instances of NR_CPUS. I found very
few instances of this bug, if any. But the patch converts lots of open-coded
test to use the preferred helper macros.
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove the assumption that driver_register() returns the number of devices
bound to the driver. In fact, it returns zero for success or a negative
error value.
Nobody uses the return value of of_register_driver() anyway.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
arch/powerpc/mm/mem.c: In function `add_memory':
arch/powerpc/mm/mem.c:128: warning: assignment makes integer from pointer without a cast
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Quite a long time back, prepare_hugepage_range() replaced
is_aligned_hugepage_range() as the callback from mm/mmap.c to arch code to
verify if an address range is suitable for a hugepage mapping.
is_aligned_hugepage_range() stuck around, but only to implement
prepare_hugepage_range() on archs which didn't implement their own.
Most archs (everything except ia64 and powerpc) used the same
implementation of is_aligned_hugepage_range(). On powerpc, which
implements its own prepare_hugepage_range(), the custom version was never
used.
In addition, "is_aligned_hugepage_range()" was a bad name, because it
suggests it returns true iff the given range is a good hugepage range,
whereas in fact it returns 0-or-error (so the sense is reversed).
This patch cleans up by abolishing is_aligned_hugepage_range(). Instead
prepare_hugepage_range() is defined directly. Most archs use the default
version, which simply checks the given region is aligned to the size of a
hugepage. ia64 and powerpc define custom versions. The ia64 one simply
checks that the range is in the correct address space region in addition to
being suitably aligned. The powerpc version (just as previously) checks
for suitable addresses, and if necessary performs low-level MMU frobbing to
set up new areas for use by hugepages.
No libhugetlbfs testsuite regressions on ppc64 (POWER5 LPAR).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
set_page_count usage outside mm/ is limited to setting the refcount to 1.
Remove set_page_count from outside mm/, and replace those users with
init_page_count() and set_page_refcounted().
This allows more debug checking, and tighter control on how code is allowed
to play around with page->_count.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A couple of places set_page_count(page, 1) that don't need to.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In mm_init_ppc64() we calculate the location of the "IO hole", but then
no one ever looks at the value. So don't bother.
That's actually all mm_init_ppc64() does, so get rid of it too.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add the command line args to the device tree as /chosen/bootargs.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add /system-id, /model and /compatible to the iSeries device tree.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add strne2a() which converts a string from EBCDIC to ASCII.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make mf_get_rtc(), mf_get_boot_rtc() and mf_set_rtc() static, cause they can
be. We need to move mf_set_rtc() to avoid a forward declaration.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These routines just call through to the mf routines, so point ppc_md straight
at the mf routines. We need to pass the cmd through to mf_reboot to make it
work, but that seems reasonable.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Some cleanups in the iSeries code.
- Make mf_display_progress() check mf_initialized rather than the caller.
- Set mf_initialized in mf_init() rather than in setup.c
- Then move mf_initialized into mf.c, the only place it's used.
- Move the mf related logic from iSeries_progress() to mf_display_progress()
- Use a #define to size the pending_event_prealloc array
- Use that define in the initialsation loop rather than sizeof jiggery pokery
- Remove stupid comment(s)
- Mark stuff static and/or __init
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It has been decreed that platform numbers are evil, so as a step in that
direction, replace platform_is_lpar() with a FW_FEATURE_LPAR bit.
Currently FW_FEATURE_LPAR really means i/pSeries LPAR, in the future we might
have to clean that up if we need to be more specific about what LPAR actually
means. But that's another patch ...
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When iommu_init_early_pSeries() was added, ages ago, we forgot to remove
the code that checks /chosen/linux,iommu-off in pSeries_init_early(). We
do it now in iommu_init_early_pSeries().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
htab_bolt_mapping() takes a vstart and pstart parameter, but all but one of
its callers actually pass it vstart and vstart. Luckily before it passes
paddr (calculated from paddr) to the hpte_insert routines it calls
virt_to_abs() (aka. __pa()) on the address, so there isn't actually a bug.
map_io_page() however does pass pstart properly, so currently it's broken
AFAICT because we're calling __pa(paddr) which will get us something very
large. Presumably no one's calling map_io_page() in the right context.
Anyway, change htab_bolt_mapping() callers to properly pass pstart, and then
use it properly in htab_bolt_mapping(), ie. don't call __pa() on it again.
Booted on p5 LPAR, iSeries and Power3.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We can plug the boot cpu into its node independently of whether numa
topology is detected. And numa_setup_cpu does the right thing for all
cases now, so remove special-casing for non-numa from the cpu hotplug
callback.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The powerpc numa code unconditionally onlines all nodes from 0 to the
highest node id found, regardless of whether cpus or memory are
present in the nodes. This wastes 8K per node and complicates some
cpu and memory hotplug situations, such as adding a resource that
doesn't map to one of the nodes discovered at boot.
Set nodes online as resources are scanned. Fall back to node 0 only
when we're sure this isn't a NUMA machine.
Instead of defaulting to node 0 for cases of hot-adding a resource
which doesn't belong to any initialized node, assign it to the first
online node.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Code to handle Power4's invalid node id (0xffff) is duplicated for cpu
and memory. Better to handle this case in one place --
of_node_to_nid. Overall behavior should be unchanged.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Since we effectively treat the domain ids given to us by firmare as
logical node ids, make this explicit (basically s/numa_domain/nid/).
No functional changes, only variable and function names are modified.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
map_cpu_to_node does not need to be inline, it is never called in a
hot path.
map_cpu_to_node, numa_setup_cpu, and find_cpu_node can be marked
__cpuinit, as they are never used after boot if CONFIG_HOTPLUG_CPU=n.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add debug statement for map_cpu_to_node; it's useful for cpu hotplug.
Clarify debug statement about not finding the numa reference points
property.
Don't print a meaningless associativity depth (-1) on non-numa systems.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At boot, the numa code is assigning boot_cpuid to node 0
unconditionally. Basically, numa_setup_cpu is being stupid about it,
but this is the minimal fix -- just call numa_setup_cpu(boot_cpuid)
later, after all nodes have been set online.
Signed-off-by: Nathan Lynch <nathanl@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
My patch (d7a5b2ffa1) to always panic if
lmb_alloc() fails is broken because it checks alloc < 0, but should be
checking alloc == 0.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Dump a stream of rawbytes with a new 'dr' command.
Produces less output and it is simpler to feed the output to scripts.
Also, dr has no dumpsize limits.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The dynamic add path for PCI Host Bridges can fail to configure children
adapters under P5IOC controllers. It fails to properly fixup bus/device
resources, and it fails to properly enable EEH. Both of these steps
need to occur before any children devices are enabled in
pci_bus_add_devices().
Signed-off-by: John Rose <johnrose@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
remove warnings when building a 64bit kernel.
smp_call_function triggers also with 32bit kernel.
WARNING: vmlinux: duplicate symbol 'smp_call_function' previous definition was in vmlinux
arch/powerpc/kernel/ppc_ksyms.c:164:EXPORT_SYMBOL(smp_call_function);
arch/powerpc/kernel/smp.c:300:EXPORT_SYMBOL(smp_call_function);
WARNING: vmlinux: duplicate symbol 'ioremap' previous definition was in vmlinux
arch/powerpc/kernel/ppc_ksyms.c:113:EXPORT_SYMBOL(ioremap);
arch/powerpc/mm/pgtable_64.c:321:EXPORT_SYMBOL(ioremap);
WARNING: vmlinux: duplicate symbol '__ioremap' previous definition was in vmlinux
arch/powerpc/kernel/ppc_ksyms.c:117:EXPORT_SYMBOL(__ioremap);
arch/powerpc/mm/pgtable_64.c:322:EXPORT_SYMBOL(__ioremap);
WARNING: vmlinux: duplicate symbol 'iounmap' previous definition was in vmlinux
arch/powerpc/kernel/ppc_ksyms.c:118:EXPORT_SYMBOL(iounmap);
arch/powerpc/mm/pgtable_64.c:323:EXPORT_SYMBOL(iounmap);
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We should be memset'ing the data we are pointing to, not the pointer
itself. This is in an error path so we probably don't hit it much.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch fixes incorrect setting of powersave_nap to 1 on all
PowerMacs, potentially causing memory corruption on some models. This
bug was introuced by me during the 32/64 bits merge.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The wording of the CRASH_DUMP Kconfig option is not very clear. It gives you a
kernel that can be used _as_ the kdump kernel, not a kernel that can boot into
a kdump kernel.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
