It appears that the pcim_iomap_regions() function doesn't get the error
handling right. It BUGs early at boot with a backtrace along the lines of:
ahci_init
pci_register_driver
driver_register
[...]
ahci_init_one
pcim_iomap_region
pcim_iounmap
The following patch allows me to boot. Only the if(mask..) continue;
part fixes the problem actually, the gotos where changed so that we
don't try to unmap something we couldn't map anyway.
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Drivers registering IRQ handlers with SA_SHIRQ really ought to be able to
handle an interrupt happening before request_irq() returns. They also
ought to be able to handle an interrupt happening during the start of their
call to free_irq(). Let's test that hypothesis....
[bunk@stusta.de: Kconfig fixes]
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The return value of scnprintf() never exceeds @size.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Split the implementation-agnostic stuff in separate files.
* Make sure that targets using non-default request_irq() pull
kernel/irq/devres.o
* Introduce new symbols (HAS_IOPORT and HAS_IOMEM) defaulting to positive;
allow architectures to turn them off (we needed these symbols anyway for
dependencies of quite a few drivers).
* protect the ioport-related parts of lib/devres.o with CONFIG_HAS_IOPORT.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the few references to the obsolete kernel config option
DEBUG_RWSEMS.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Part of long forgotten patch
http://groups.google.com/group/fa.linux.kernel/msg/e98e941ce1cf29f6?dmode=source
Since then, m32r grabbed two copies.
Leave s390 copy because of important absence of CONFIG_VT, but remove
references to non-existent timerlist_lock. ia64 also loses timerlist_lock.
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A variety of (mostly) innocuous fixes to the embedded kernel-doc content in
source files, including:
* make multi-line initial descriptions single line
* denote some function names, constants and structs as such
* change erroneous opening '/*' to '/**' in a few places
* reword some text for clarity
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
devres change moved iomap.o from obj-$(CONFIG_GENERIC_IOMAP) to lib-y
making it not linked if no in-kernel driver uses it. Fix it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement pcim_iomap_regions(). This function takes mask of BARs to
request and iomap. No BAR should have length of zero. BARs are
iomapped using pcim_iomap_table().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement device resource management, in short, devres. A device
driver can allocate arbirary size of devres data which is associated
with a release function. On driver detach, release function is
invoked on the devres data, then, devres data is freed.
devreses are typed by associated release functions. Some devreses are
better represented by single instance of the type while others need
multiple instances sharing the same release function. Both usages are
supported.
devreses can be grouped using devres group such that a device driver
can easily release acquired resources halfway through initialization
or selectively release resources (e.g. resources for port 1 out of 4
ports).
This patch adds devres core including documentation and the following
managed interfaces.
* alloc/free : devm_kzalloc(), devm_kzfree()
* IO region : devm_request_region(), devm_release_region()
* IRQ : devm_request_irq(), devm_free_irq()
* DMA : dmam_alloc_coherent(), dmam_free_coherent(),
dmam_declare_coherent_memory(), dmam_pool_create(),
dmam_pool_destroy()
* PCI : pcim_enable_device(), pcim_pin_device(), pci_is_managed()
* iomap : devm_ioport_map(), devm_ioport_unmap(), devm_ioremap(),
devm_ioremap_nocache(), devm_iounmap(), pcim_iomap_table(),
pcim_iomap(), pcim_iounmap()
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The problem. When implementing a network namespace I need to be able
to have multiple network devices with the same name. Currently this
is a problem for /sys/class/net/*.
What I want is a separate /sys/class/net directory in sysfs for each
network namespace, and I want to name each of them /sys/class/net.
I looked and the VFS actually allows that. All that is needed is
for /sys/class/net to implement a follow link method to redirect
lookups to the real directory you want.
Implementing a follow link method that is sensitive to the current
network namespace turns out to be 3 lines of code so it looks like a
clean approach. Modifying sysfs so it doesn't get in my was is a bit
trickier.
I am calling the concept of multiple directories all at the same path
in the filesystem shadow directories. With the directory entry really
at that location the shadow master.
The following patch modifies sysfs so it can handle a directory
structure slightly different from the kobject tree so I can implement
the shadow directories for handling /sys/class/net/.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If we allow NULL as the new parent in device_move(), we need to make sure
that the device is placed into the same place as it would if it was
newly registered:
- Consider the device virtual tree. In order to be able to reuse code,
setup_parent() has been tweaked a bit.
- kobject_move() can fall back to the kset's kobject.
- sysfs_move_dir() uses the sysfs root dir as fallback.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It should be ok to pass in NULL for some kobject functions, so add error
checking for all exported kobject functions to be more robust.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add abstraction so that the file can be used by environments other than IA64
and EM64T, namely for Xen.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
- add proper __init decoration to swiotlb's init code (and the code calling
it, where not already the case)
- replace uses of 'unsigned long' with dma_addr_t where appropriate
- do miscellaneous simplicfication and cleanup
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Convert all phys_to_virt/virt_to_phys uses to bus_to_virt/virt_to_bus, as is
what is meant and what is needed in (at least) some virtualized environments
like Xen.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch fixes
- marking I-cache clean of pages DMAed to now only done for IA64
- broken multiple inclusion in include/asm-x86_64/swiotlb.h
- missing call to mark_clean in swiotlb_sync_sg()
- a (perhaps only theoretical) issue in swiotlb_dma_supported() when
io_tlb_end is exactly at the end of memory
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Since kobject_uevent() function does not return an integer value to
indicate if its operation was completed with success or not, it is worth
changing it in order to report a proper status (success or error) instead
of returning void.
[randy.dunlap@oracle.com: Fix inline kobject functions]
Cc: Mauricio Lin <mauriciolin@gmail.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
With WARN_ON addition to kobject_init()
[ http://kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.19/2.6.19-mm1/dont-use/broken-out/gregkh-driver-kobject-warn.patch ]
I started seeing following WARNING on CPU offline followed by online on my
x86_64 system.
WARNING at lib/kobject.c:172 kobject_init()
Call Trace:
[<ffffffff8020ab45>] dump_trace+0xaa/0x3ef
[<ffffffff8020aec4>] show_trace+0x3a/0x50
[<ffffffff8020b0f6>] dump_stack+0x15/0x17
[<ffffffff80350abc>] kobject_init+0x3f/0x8a
[<ffffffff80350be1>] kobject_register+0x1a/0x3e
[<ffffffff803bbd89>] sysdev_register+0x5b/0xf9
[<ffffffff80211d0b>] mce_create_device+0x77/0xf4
[<ffffffff80211dc2>] mce_cpu_callback+0x3a/0xe5
[<ffffffff805632fd>] notifier_call_chain+0x26/0x3b
[<ffffffff8023f6f3>] raw_notifier_call_chain+0x9/0xb
[<ffffffff802519bf>] _cpu_up+0xb4/0xdc
[<ffffffff80251a12>] cpu_up+0x2b/0x42
[<ffffffff803bef00>] store_online+0x4a/0x72
[<ffffffff803bb6ce>] sysdev_store+0x24/0x26
[<ffffffff802baaa2>] sysfs_write_file+0xcf/0xfc
[<ffffffff8027fc6f>] vfs_write+0xae/0x154
[<ffffffff80280418>] sys_write+0x47/0x6f
[<ffffffff8020963e>] system_call+0x7e/0x83
DWARF2 unwinder stuck at system_call+0x7e/0x83
Leftover inexact backtrace:
This is a false positive as mce.c is unregistering/registering sysfs
interfaces cleanly on hotplug.
kref_put() and conditional decrement of refcnt seems to be the root cause
for this and the patch below resolves the issue for me.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It has caused more problems than it ever really solved, and is
apparently not getting cleaned up and fixed. We can put it back when
it's stable and isn't likely to make warning or bug events worse.
In the meantime, enable frame pointers for more readable stack traces.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove useless includes of linux/io.h, don't even try to build iomap_copy
on uml (it doesn't have readb() et.al., so...)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When some objects are allocated by one CPU but freed by another CPU we can
consume lot of cycles doing divides in obj_to_index().
(Typical load on a dual processor machine where network interrupts are
handled by one particular CPU (allocating skbufs), and the other CPU is
running the application (consuming and freeing skbufs))
Here on one production server (dual-core AMD Opteron 285), I noticed this
divide took 1.20 % of CPU_CLK_UNHALTED events in kernel. But Opteron are
quite modern cpus and the divide is much more expensive on oldest
architectures :
On a 200 MHz sparcv9 machine, the division takes 64 cycles instead of 1
cycle for a multiply.
Doing some math, we can use a reciprocal multiplication instead of a divide.
If we want to compute V = (A / B) (A and B being u32 quantities)
we can instead use :
V = ((u64)A * RECIPROCAL(B)) >> 32 ;
where RECIPROCAL(B) is precalculated to ((1LL << 32) + (B - 1)) / B
Note :
I wrote pure C code for clarity. gcc output for i386 is not optimal but
acceptable :
mull 0x14(%ebx)
mov %edx,%eax // part of the >> 32
xor %edx,%edx // useless
mov %eax,(%esp) // could be avoided
mov %edx,0x4(%esp) // useless
mov (%esp),%ebx
[akpm@osdl.org: small cleanups]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add MODULE_* attributes to the new bit reversal library. Most notably
MODULE_LICENSE which prevents superfluous kernel tainting.
Signed-off-by: Cal Peake <cp@absolutedigital.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Refactor Kconfig content to maximize nesting of menus by menuconfig and
xconfig.
Tested by simultaneously running `make xconfig` with and without
patch, and comparing displays.
Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Trivial optimization and simplification of should_fail().
Do cheaper disqualification tests first (performance gain not quantified).
Simplify logic; eliminate goto.
Signed-off-by: Don Mullis <dwm@meer.net>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clamp /debug/fail*/stacktrace-depth to MAX_STACK_TRACE_DEPTH. Ensures that a
read of /debug/fail*/stacktrace-depth always returns a truthful answer.
Signed-off-by: Don Mullis <dwm@meer.net>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use bool-true-false throughout.
Signed-off-by: Don Mullis <dwm@meer.net>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
`select' doesn't work very well. With alpha `make allmodconfig' we end up
with CONFIG_STACKTRACE enabled, so we end up with undefined save_stacktrace()
at link time.
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Fix some spelling and grammatical errors
- Make the Kconfig menu more conventional. First you select
fault-injection, then under that you select particular clients of it.
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides stacktrace filtering feature.
The stacktrace filter allows failing only for the caller you are
interested in.
For example someone may want to inject kmalloc() failures into
only e100 module. they want to inject not only direct kmalloc() call,
but also indirect allocation, too.
- e100_poll --> netif_receive_skb --> packet_rcv_spkt --> skb_clone
--> kmem_cache_alloc
This patch enables to detect function calls like this by stacktrace
and inject failures. The script Documentaion/fault-injection/failmodule.sh
helps it.
The range of text section of loaded e100 is expected to be
[/sys/module/e100/sections/.text, /sys/module/e100/sections/.exit.text)
So failmodule.sh stores these values into /debug/failslab/address-start
and /debug/failslab/address-end. The maximum stacktrace depth is specified
by /debug/failslab/stacktrace-depth.
Please see the example that demonstrates how to inject slab allocation
failures only for a specific module
in Documentation/fault-injection/fault-injection.txt
[dwm@meer.net: reject failure if any caller lies within specified range]
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides process filtering feature.
The process filter allows failing only permitted processes
by /proc/<pid>/make-it-fail
Please see the example that demostrates how to inject slab allocation
failures into module init/cleanup code
in Documentation/fault-injection/fault-injection.txt
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides fault-injection capability for disk IO.
Boot option:
fail_make_request=<probability>,<interval>,<space>,<times>
<interval> -- specifies the interval of failures.
<probability> -- specifies how often it should fail in percent.
<space> -- specifies the size of free space where disk IO can be issued
safely in bytes.
<times> -- specifies how many times failures may happen at most.
Debugfs:
/debug/fail_make_request/interval
/debug/fail_make_request/probability
/debug/fail_make_request/specifies
/debug/fail_make_request/times
Example:
fail_make_request=10,100,0,-1
echo 1 > /sys/blocks/hda/hda1/make-it-fail
generic_make_request() on /dev/hda1 fails once per 10 times.
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides fault-injection capability for alloc_pages()
Boot option:
fail_page_alloc=<interval>,<probability>,<space>,<times>
<interval> -- specifies the interval of failures.
<probability> -- specifies how often it should fail in percent.
<space> -- specifies the size of free space where memory can be
allocated safely in pages.
<times> -- specifies how many times failures may happen at most.
Debugfs:
/debug/fail_page_alloc/interval
/debug/fail_page_alloc/probability
/debug/fail_page_alloc/specifies
/debug/fail_page_alloc/times
/debug/fail_page_alloc/ignore-gfp-highmem
/debug/fail_page_alloc/ignore-gfp-wait
Example:
fail_page_alloc=10,100,0,-1
The page allocation (alloc_pages(), ...) fails once per 10 times.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides fault-injection capability for kmalloc.
Boot option:
failslab=<interval>,<probability>,<space>,<times>
<interval> -- specifies the interval of failures.
<probability> -- specifies how often it should fail in percent.
<space> -- specifies the size of free space where memory can be
allocated safely in bytes.
<times> -- specifies how many times failures may happen at most.
Debugfs:
/debug/failslab/interval
/debug/failslab/probability
/debug/failslab/specifies
/debug/failslab/times
/debug/failslab/ignore-gfp-highmem
/debug/failslab/ignore-gfp-wait
Example:
failslab=10,100,0,-1
slab allocation (kmalloc(), kmem_cache_alloc(),..) fails once per 10 times.
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides base functions implement to fault-injection
capabilities.
- The function should_fail() is taken from failmalloc-1.0
(http://www.nongnu.org/failmalloc/)
[akpm@osdl.org: cleanups, comments, add __init]
Cc: <okuji@enbug.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch replaces bitreverse() by bitrev32. The only users of bitreverse()
are crc32 itself and via-velocity.
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides two bit reverse functions and bit reverse table.
- reverse the order of bits in a u32 value
u8 bitrev8(u8 x);
- reverse the order of bits in a u32 value
u32 bitrev32(u32 x);
- byte reverse table
const u8 byte_rev_table[256];
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This makes i386 use the generic BUG machinery. There are no functional
changes from the old i386 implementation.
The main advantage in using the generic BUG machinery for i386 is that the
inlined overhead of BUG is just the ud2a instruction; the file+line(+function)
information are no longer inlined into the instruction stream. This reduces
cache pollution, and makes disassembly work properly.
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds common handling for kernel BUGs, for use by architectures as
they wish. The code is derived from arch/powerpc.
The advantages of having common BUG handling are:
- consistent BUG reporting across architectures
- shared implementation of out-of-line file/line data
- implement CONFIG_DEBUG_BUGVERBOSE consistently
This means that in inline impact of BUG is just the illegal instruction
itself, which is an improvement for i386 and x86-64.
A BUG is represented in the instruction stream as an illegal instruction,
which has file/line information associated with it. This extra information is
stored in the __bug_table section in the ELF file.
When the kernel gets an illegal instruction, it first confirms it might
possibly be from a BUG (ie, in kernel mode, the right illegal instruction).
It then calls report_bug(). This searches __bug_table for a matching
instruction pointer, and if found, prints the corresponding file/line
information. If report_bug() determines that it wasn't a BUG which caused the
trap, it returns BUG_TRAP_TYPE_NONE.
Some architectures (powerpc) implement WARN using the same mechanism; if the
illegal instruction was the result of a WARN, then report_bug(Q) returns
CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG.
lib/bug.c keeps a list of loaded modules which can be searched for __bug_table
entries. The architecture must call
module_bug_finalize()/module_bug_cleanup() from its corresponding
module_finalize/cleanup functions.
Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount.
At the very least, filename and line information will not be recorded for each
but, but architectures may decide to store no extra information per BUG at
all.
Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so
architectures will generally have to include an infinite loop (or similar) in
the BUG code, so that gcc knows execution won't continue beyond that point.
gcc does have a __builtin_trap() operator which may be useful to achieve the
same effect, unfortunately it cannot be used to actually implement the BUG
itself, because there's no way to get the instruction's address for use in
generating the __bug_table entry.
[randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors]
[bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h]
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make the locking self-test failures (of 'FAILURE' type) easier to debug by
printing more information.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Always build hweight8/16/32/64() functions into the kernel so that loadable
modules may use them.
I didn't remove GENERIC_HWEIGHT since ALPHA_EV67, ia64, and some variants
of UltraSparc(64) provide their own hweight functions.
Fixes config/build problems with NTFS=m and JOYSTICK_ANALOG=m.
Kernel: arch/x86_64/boot/bzImage is ready (#19)
Building modules, stage 2.
MODPOST 94 modules
WARNING: "hweight32" [fs/ntfs/ntfs.ko] undefined!
WARNING: "hweight16" [drivers/input/joystick/analog.ko] undefined!
WARNING: "hweight8" [drivers/input/joystick/analog.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There was lots of #ifdef noise in the kernel due to hotcpu_notifier(fn,
prio) not correctly marking 'fn' as used in the !HOTPLUG_CPU case, and thus
generating compiler warnings of unused symbols, hence forcing people to add
#ifdefs.
the compiler can skip truly unused functions just fine:
text data bss dec hex filename
1624412 728710 3674856 6027978 5bfaca vmlinux.before
1624412 728710 3674856 6027978 5bfaca vmlinux.after
[akpm@osdl.org: topology.c fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This allows a hyphenated range of positive numbers in the string passed
to command line helper function, get_options.
Currently the command line option "isolcpus=" takes as its argument a
list of cpus.
Format: <cpu number>,...,<cpu number>
Valid values of <cpu_number> include all cpus, 0 to "number of CPUs in
system - 1". This can get extremely long when isolating the majority of
cpus on a large system. The kernel isolcpus code would not need any
changing to use this feature. To use it, the change would be in the
command line format for 'isolcpus='
Format:
<cpu number>,...,<cpu number>
or
<cpu number>-<cpu number> (must be a positive range in ascending
order.)
or a mixture
<cpu number>,...,<cpu number>-<cpu number>
Signed-off-by: Derek Fults <dfults@sgi.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Print the other (hopefully) known good pointer when list_head debugging
too, which may yield additional clues.
Also fix for 80-columns to win akpm brownie points.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
