Implement SMP alternatives, i.e. switching at runtime between different
code versions for UP and SMP. The code can patch both SMP->UP and UP->SMP.
The UP->SMP case is useful for CPU hotplug.
With CONFIG_CPU_HOTPLUG enabled the code switches to UP at boot time and
when the number of CPUs goes down to 1, and switches to SMP when the number
of CPUs goes up to 2.
Without CONFIG_CPU_HOTPLUG or on non-SMP-capable systems the code is
patched once at boot time (if needed) and the tables are released
afterwards.
The changes in detail:
* The current alternatives bits are moved to a separate file,
the SMP alternatives code is added there.
* The patch adds some new elf sections to the kernel:
.smp_altinstructions
like .altinstructions, also contains a list
of alt_instr structs.
.smp_altinstr_replacement
like .altinstr_replacement, but also has some space to
save original instruction before replaving it.
.smp_locks
list of pointers to lock prefixes which can be nop'ed
out on UP.
The first two are used to replace more complex instruction
sequences such as spinlocks and semaphores. It would be possible
to deal with the lock prefixes with that as well, but by handling
them as special case the table sizes become much smaller.
* The sections are page-aligned and padded up to page size, so they
can be free if they are not needed.
* Splitted the code to release init pages to a separate function and
use it to release the elf sections if they are unused.
Signed-off-by: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Print stack backtraces in multiple columns, saving screen space. Number of
columns is configurable and defaults to one so behavior is
backwards-compatible.
Also removes the brackets around addresses when printing more
that one entry per line so they print as:
<address>
instead of:
[<address>]
This helps multiple entries fit better on one line.
Original idea by Dave Jones, taken from x86_64.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make CONFIG_REGPARM enabled by default. It's a noticable win both for size
and for performance, and gcc[34] handles it correctly.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
REGPARM has already gotten much testing, what about removing the
dependency on EXPERIMENTAL?
Additionally, this patch does:
- remove the useless "default n"
- remove note regarding binary only modules (nowadays, there are even
some binary only modules compiled with REGPARM=y available)
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch address several issues in the current BSD Secure Levels code:
o plaintext_to_sha1: Missing check for a NULL return from __get_free_page
o passwd_write_file: A page is leaked if the password is wrong.
o fix securityfs registration order
o seclvl_init is a mess and can't properly tolerate failures, failure
path is upside down (deldif and delf should be switched)
Cleanups:
o plaintext_to_sha1: Use buffers passed in
o passwd_write_file: Use kmalloc() instead of get_zeroed_page()
o passwd_write_file: hashedPassword comparison is just memcmp
o s/ENOSYS/EINVAL/
o misc
(akpm: after some discussion it appears that the BSD secure levels feature
should be scheduled for removal. But for now, let's fix these problems up).
Signed-off-by: Davi Arnaut <davi.arnaut@gmail.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Stephen Smalley <sds@epoch.ncsc.mil>
Cc: James Morris <jmorris@namei.org>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Both R1BIO_Barrier and R1BIO_Returned are 4 !!!!
This means that barrier requests don't get returned (i.e. b_endio called)
because it looks like they already have been.
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We have noticed lockups during boot when stress testing kexec on ppc64.
Two cpus would deadlock in scheduler code trying to grab already taken
spinlocks.
The double_rq_lock code uses the address of the runqueue to order the
taking of multiple locks. This address is a per cpu variable:
if (rq1 < rq2) {
spin_lock(&rq1->lock);
spin_lock(&rq2->lock);
} else {
spin_lock(&rq2->lock);
spin_lock(&rq1->lock);
}
On the other hand, the code in wake_sleeping_dependent uses the cpu id
order to grab locks:
for_each_cpu_mask(i, sibling_map)
spin_lock(&cpu_rq(i)->lock);
This means we rely on the address of per cpu data increasing as cpu ids
increase. While this will be true for the generic percpu implementation it
may not be true for arch specific implementations.
One way to solve this is to always take runqueues in cpu id order. To do
this we add a cpu variable to the runqueue and check it in the
double runqueue locking functions.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Merge clash will have broken sparc64. Synch up its online_page
implementation with powerpc, which was identical until the
set_page_count removal.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Documentation: Added FSL SOC SEC node definition
Updated the documentation to include the definition of the SEC device
node format for Freescale SOC devices.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.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.
All callers of macio_register_driver() either ignore the return value or
return it as the return value of a module_init() function.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.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>
drivers/macintosh/via-pmu.c:164: warning: `sleep_in_progress' defined but not used
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now powerpc uses the generic RTC stuff we should not enable the old RTC.
Doing so will result in hangs at boot.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
powerbook_sleep_grackle is only called inside via-pmu, from pmu_ioctl()
Signed-off-by: Olaf Hering <olh@suse.de>
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>
If the debug driver is built-in, link it in last, so that any real
drivers will probe first, rather than having the debug driver pick the
first scsi slots..
Signed-off-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[TCP]: Do not use inet->id of global tcp_socket when sending RST.
[NETFILTER]: Fix undefined references to get_h225_addr
[NETFILTER]: futher {ip,ip6,arp}_tables unification
[NETFILTER]: Fix xt_policy address matching
[NETFILTER]: nf_conntrack: support for layer 3 protocol load on demand
[NETFILTER]: x_tables: set the protocol family in x_tables targets/matches
[NETFILTER]: conntrack: cleanup the conntrack ID initialization
[NETFILTER]: nfnetlink_queue: fix nfnetlink message size
[NETFILTER]: ctnetlink: Fix expectaction mask dumping
[NETFILTER]: Fix Kconfig typos
[NETFILTER]: Fix ip6tables breakage from {get,set}sockopt compat layer
* master.kernel.org:/home/rmk/linux-2.6-serial:
[SERIAL] Merge avlab serial board entries in parport_serial
[SERIAL] kernel console should send CRLF not LFCR
hi,
this fixes coverity bug #888, where the variable
dev is used uninitialized. I assume the programmer
meant to use mdev, which is initialized.
Compile tested only.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>