The ftrace_dump_on_oops kernel parameter, sysctl and sysrq let one
dump every cpu buffers when an oops or panic happens.
It's nice when you have few cpus but it may take ages if have many,
plus you miss the real origin of the problem in all the cpu traces.
Sometimes, all you need is to dump the cpu buffer that triggered the
opps, most of the time it is our main interest.
This patch modifies ftrace_dump_on_oops to handle this choice.
The ftrace_dump_on_oops kernel parameter, when it comes alone, has
the same behaviour than before. But ftrace_dump_on_oops=orig_cpu
will only dump the buffer of the cpu that oops'ed.
Similarly, sysctl kernel.ftrace_dump_on_oops=1 and
echo 1 > /proc/sys/kernel/ftrace_dump_on_oops keep their previous
behaviour. But setting 2 jumps into cpu origin dump mode.
v2: Fix double setup
v3: Fix spelling issues reported by Randy Dunlap
v4: Also update __ftrace_dump in the selftests
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
hvc_console: Fix race between hvc_close and hvc_remove
virtio: disable multiport console support.
virtio: console makes incorrect assumption about virtio API
virtio: console: Fix early_put_chars usage
MAINTAINERS: Put the virtio-console entry in correct alphabetical order
I don't claim to understand the tty layer, but it seems like hvc_open and
hvc_close should be balanced in their kref reference counting.
Right now we get a kref every call to hvc_open:
if (hp->count++ > 0) {
tty_kref_get(tty); <----- here
spin_unlock_irqrestore(&hp->lock, flags);
hvc_kick();
return 0;
} /* else count == 0 */
tty->driver_data = hp;
hp->tty = tty_kref_get(tty); <------ or here if hp->count was 0
But hvc_close has:
tty_kref_get(tty);
if (--hp->count == 0) {
...
/* Put the ref obtained in hvc_open() */
tty_kref_put(tty);
...
}
tty_kref_put(tty);
Since the outside kref get/put balance we only do a single kref_put when
count reaches 0.
The patch below changes things to call tty_kref_put once for every
hvc_close call, and with that my machine boots fine.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Move MULTIPORT feature and related config changes
out of exported headers, and disable the feature
at runtime.
At this point, it seems less risky to keep code around
until we can enable it than rip it out completely.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The get_buf() API sets the second arg to the number of bytes *written*
by the other side; in this case it should be zero as these are output buffers.
lguest gets this right (obviously kvm's console doesn't), resulting in
continual buildup of console writes.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Amit Shah <amit.shah@redhat.com>
Currently early_put_chars is not used by virtio_console because it can
only be used once a port has been found, at which point it's too late
because it is no longer needed. This patch should fix it.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Move around the entry for virtio-console to keep the file sorted.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
rwsems can be used with IRQs disabled, particularily in early boot
before IRQs are enabled. Currently the spin_unlock_irq() usage in the
slow-patch will unconditionally enable interrupts and cause problems
since interrupts are not yet initialized or enabled.
This patch uses save/restore versions of IRQ spinlocks in the slowpath
to ensure interrupts are not unintentionally disabled.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
x86: Fix double enable_IR_x2apic() call on SMP kernel on !SMP boards
x86: Increase CONFIG_NODES_SHIFT max to 10
ibft, x86: Change reserve_ibft_region() to find_ibft_region()
x86, hpet: Fix bug in RTC emulation
x86, hpet: Erratum workaround for read after write of HPET comparator
bootmem, x86: Fix 32bit numa system without RAM on node 0
nobootmem, x86: Fix 32bit numa system without RAM on node 0
x86: Handle overlapping mptables
x86: Make e820_remove_range to handle all covered case
x86-32, resume: do a global tlb flush in S4 resume
This hushes the following warning:
arch/arm/mach-davinci/include/mach/da8xx.h:104: warning: ‘struct platform_device’
declared inside parameter list
arch/arm/mach-davinci/include/mach/da8xx.h:104: warning: its scope is only this
definition or declaration, which is probably not what you want
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: mixart: range checking proc file
ALSA: hda - Fix a wrong array range check in patch_realtek.c
ALSA: ASoC: move dma_data from snd_soc_dai to snd_soc_pcm_stream
ALSA: hda - Enable amplifiers on Acer Inspire 6530G
ASoC: Only do WM8994 bias off transition from standby
ASoC: Don't use DCS_DATAPATH_BUSY for WM hubs devices
ASoC: Don't do runtime wm_hubs DC servo updates if using offset correction
ASoC: Support second DC servo readback method for wm_hubs
ASoC: Avoid wraparound in wm_hubs DC servo correction
ALSA: echoaudio - Eliminate use after free
ALSA: i2c: cleanup: change parameter to pointer
ALSA: hda - Add MSI blacklist for Aopen MZ915-M
ASoC: OMAP: Fix capture pointer handling for OMAP1510 to work correctly with recent ALSA PCM code
ALSA: hda - Update document about MSI and interrupts
ALSA: hda: Fix 0 dB offset for Lenovo Thinkpad models using AD1981
ALSA: hda - Add missing printk argument in previous patch
ASoC: Fix passing platform_data to ac97 bus users and fix a leak
ALSA: hda - Fix ADC/MUX assignment of ALC269 codec
ALSA: hda - Fix invalid bit values passed to snd_hda_codec_amp_stereo()
ASoC: wm8994: playback => capture
Order the debugfs statistics correctly. The values displayed through a
seq_printf() statement should be in the same order as the names in the
format string.
In the 'Lookups' line, objects created ('crt=') and lookups timed out
('tmo=') have their values transposed.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In NOMMU mode, the FRV segment handling is broken because KERNEL_DS ==
USER_DS. This causes tests of the following sort:
/* don't pin down non-user-based iovecs */
if (segment_eq(get_fs(), KERNEL_DS))
return NULL;
to malfunction.
To fix this, make USER_DS the top of RAM instead of the top of the non-IO
address space, and make KERNEL_DS one more than the top of the non-IO
address space.
Also get rid of FRV's __addr_ok() as nothing uses it.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hide uncached_access() when pgprot_noncached is not #defined. This prevents
the following warning:
CC drivers/char/mem.o
drivers/char/mem.c:229: warning: 'uncached_access' defined but not used
Repairs d7d4d849b4 ("drivers/char/mem.c:
cleanups").
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On exit paths in mxc_rtc_probe() method some resources are not freed
correctly.
This patch fixes:
* unrequested memory region containing imx RTC registers
* iounmap() isn't called on exit_free_pdata branch
* clock get rate is called for freed clock source
* clock isn't disabled on exit_put_clk branch
To simplify the fix managed device resources are used.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Vladimir Zapolskiy <vzapolskiy@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Presently, memcg's FILE_MAPPED accounting has following race with
move_account (happens at rmdir()).
increment page->mapcount (rmap.c)
mem_cgroup_update_file_mapped() move_account()
lock_page_cgroup()
check page_mapped() if
page_mapped(page)>1 {
FILE_MAPPED -1 from old memcg
FILE_MAPPED +1 to old memcg
}
.....
overwrite pc->mem_cgroup
unlock_page_cgroup()
lock_page_cgroup()
FILE_MAPPED + 1 to pc->mem_cgroup
unlock_page_cgroup()
Then,
old memcg (-1 file mapped)
new memcg (+2 file mapped)
This happens because move_account see page_mapped() which is not guarded
by lock_page_cgroup(). This patch adds FILE_MAPPED flag to page_cgroup
and move account information based on it. Now, all checks are synchronous
with lock_page_cgroup().
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Balbir Singh <balbir@in.ibm.com>
Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Andrea Righi <arighi@develer.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we look into pagemap using page-types with option -p, the value of
pfn for hugepages looks wrong (see below.) This is because pte was
evaluated only once for one vma although it should be updated for each
hugepage. This patch fixes it.
$ page-types -p 3277 -Nl -b huge
voffset offset len flags
7f21e8a00 11e400 1 ___U___________H_G________________
7f21e8a01 11e401 1ff ________________TG________________
^^^
7f21e8c00 11e400 1 ___U___________H_G________________
7f21e8c01 11e401 1ff ________________TG________________
^^^
One hugepage contains 1 head page and 511 tail pages in x86_64 and each
two lines represent each hugepage. Voffset and offset mean virtual
address and physical address in the page unit, respectively. The
different hugepages should not have the same offset value.
With this patch applied:
$ page-types -p 3386 -Nl -b huge
voffset offset len flags
7fec7a600 112c00 1 ___UD__________H_G________________
7fec7a601 112c01 1ff ________________TG________________
^^^
7fec7a800 113200 1 ___UD__________H_G________________
7fec7a801 113201 1ff ________________TG________________
^^^
OK
More info:
- This patch modifies walk_page_range()'s hugepage walker. But the
change only affects pagemap_read(), which is the only caller of hugepage
callback.
- Without this patch, hugetlb_entry() callback is called per vma, that
doesn't match the natural expectation from its name.
- With this patch, hugetlb_entry() is called per hugepte entry and the
callback can become much simpler.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>