john fastabend [Fri, 18 Nov 2011 21:35:56 +0000 (13:35 -0800)]
[SCSI] fcoe: fix fcoe in a DCB environment by adding DCB notifiers to set skb priority
Use DCB notifiers to set the skb priority to allow packets
to be steered and tagged correctly over DCB enabled drivers
that setup traffic classes.
This allows queue_mapping() routines to be removed in these
drivers that were previously inspecting the ethertype of
every skb to mark FCoE/FIP frames.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Eddie Wai [Wed, 7 Dec 2011 06:41:21 +0000 (22:41 -0800)]
[SCSI] bnx2i: Fixed kernel panic caused by unprotected task->sc->request deref
During session recovery, the conn_stop call will trigger a flush
to all outstanding SCSI cmds in the xmit queue. This will set
all outstanding task->sc to NULL prior to the session_teardown
call which frees the task memory.
In the bnx2i SCSI response processing path, only the task was being checked
for NULL under the session lock before the task->sc->request dereferencing.
If there are outstanding SCSI cmd responses pending for process, the
following kernel panic can be exposed where task->sc was found to be NULL.
Tomas Henzl [Fri, 2 Dec 2011 03:38:42 +0000 (21:38 -0600)]
[SCSI] qla4xxx: a small loop fix
When the qla4xxx_get_fwddb_entry returns QLA_ERROR
the nex_idx is not updated,
for (idx = 0; idx < max_ddbs; idx = next_idx) {
ret = qla4xxx_get_fwddb_entry(ha, idx, NULL, 0, NULL,
&next_idx, &state, &conn_err,
NULL, NULL);
if (ret == QLA_ERROR)
continue;
This means there is a risk that the 'idx < max_ddbs' condition will never
met and the loop will loop forever.
Fix this by explicitly increasing the next_idx in the error condition.
Maybe a break instead of continue is more appropriate, leaving the decision
on the qlogic maintainer.
Signed-off-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Mike Christie [Fri, 2 Dec 2011 03:38:41 +0000 (21:38 -0600)]
[SCSI] qla4xxx: fix flash/ddb support
With open-iscsi support, target entries persisted in the FLASH were not
login. Added support in the qla4xxx driver to do the login on probe
time to the target entries saved in the FLASH by user.
With this changes upgrade to the new kernel with open-iscsi support in
qla4xxx will ensure users original target entries login on driver load
Signed-off-by: Manish Rangankar <manish.rangankar@qlogic.com> Signed-off-by: Ravi Anand <ravi.anand@qlogic.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Steffen Maier [Fri, 18 Nov 2011 19:00:40 +0000 (20:00 +0100)]
[SCSI] zfcp: return early from slave_destroy if slave_alloc returned early
zfcp_scsi_slave_destroy erroneously always tried to finish its task
even if the corresponding previous zfcp_scsi_slave_alloc returned
early. This can lead to kernel page faults on accessing uninitialized
fields of struct zfcp_scsi_dev in zfcp_erp_lun_shutdown_wait. Take the
port field of the struct to determine if slave_alloc returned early.
This zfcp bug is exposed by 4e6c82b (in turn fixing f7c9c6b to be
compatible with 21208ae) which can call slave_destroy for a
corresponding previous slave_alloc that did not finish.
This patch is based on James Bottomley's fix suggestion in
http://www.spinics.net/lists/linux-scsi/msg55449.html.
Thomas Gleixner [Fri, 11 Nov 2011 19:52:01 +0000 (20:52 +0100)]
[SCSI] fcoe: Fix preempt count leak in fcoe_filter_frames()
The error exit path leaks preempt count. Add the missing put_cpu().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Yi Zou <yi.zou@intel.com> Cc: stable@kernel.org Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Andrew Vasquez [Fri, 18 Nov 2011 17:02:15 +0000 (09:02 -0800)]
[SCSI] qla2xxx: Return the correct value for a mailbox command if 82xx is in reset recovery.
We need to return QLA_FUNCTION_TIMEOUT immediately otherwise we mess up the
mailbox command state machine.
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com> Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This function can wait for 5min under certain scenarios. One of them is when
the port is down from switch and bus reset is issued. The bus reset used to
wait for 5 minutes for the loop and upper layer callers used to hang and give
stack trace because of getting stuck for 120 sec. It is legacy code that was
used when the driver used to do queuing of the commands.
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com> Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Linus Torvalds [Fri, 9 Dec 2011 22:45:44 +0000 (14:45 -0800)]
Merge git://git.samba.org/sfrench/cifs-2.6
* git://git.samba.org/sfrench/cifs-2.6:
cifs: check for NULL last_entry before calling cifs_save_resume_key
cifs: attempt to freeze while looping on a receive attempt
cifs: Fix sparse warning when calling cifs_strtoUCS
CIFS: Add descriptions to the brlock cache functions
Linus Torvalds [Fri, 9 Dec 2011 22:45:12 +0000 (14:45 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, efi: Calling __pa() with an ioremap()ed address is invalid
x86, hpet: Immediately disable HPET timer 1 if rtc irq is masked
x86/intel_mid: Kconfig select fix
x86/intel_mid: Fix the Kconfig for MID selection
Linus Torvalds [Fri, 9 Dec 2011 22:41:50 +0000 (14:41 -0800)]
Merge branch 'spi/for-3.2' of git://git.pengutronix.de/git/wsa/linux-2.6
* 'spi/for-3.2' of git://git.pengutronix.de/git/wsa/linux-2.6:
spi/gpio: fix section mismatch warning
spi/fsl-espi: disable CONFIG_SPI_FSL_ESPI=m build
spi/nuc900: Include linux/module.h
spi/ath79: fix compile error due to missing include
Linus Torvalds [Fri, 9 Dec 2011 16:18:08 +0000 (08:18 -0800)]
Merge branch 'for-linus' of git://neil.brown.name/md
* 'for-linus' of git://neil.brown.name/md:
md: raid5 crash during degradation
md/raid5: never wait for bad-block acks on failed device.
md: ensure new badblocks are handled promptly.
md: bad blocks shouldn't cause a Blocked status on a Faulty device.
md: take a reference to mddev during sysfs access.
md: refine interpretation of "hold_active == UNTIL_IOCTL".
md/lock: ensure updates to page_attrs are properly locked.
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile: use new generic {enable,disable}_percpu_irq() routines
drivers/net/ethernet/tile: use skb_frag_page() API
asm-generic/unistd.h: support new process_vm_{readv,write} syscalls
arch/tile: fix double-free bug in homecache_free_pages()
arch/tile: add a few #includes and an EXPORT to catch up with kernel changes.
Linus Torvalds [Fri, 9 Dec 2011 16:07:42 +0000 (08:07 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda/realtek - Fix lost speaker volume controls
ALSA: hda/realtek - Create "Bass Speaker" for two speaker pins
ALSA: hda/realtek - Don't create extra controls with channel suffix
ALSA: hda - Fix remaining VREF mute-LED NID check in post-3.1 changes
ALSA: hda - Fix GPIO LED setup for IDT 92HD75 codecs
ASoC: Provide a more complete DMA driver stub
ASoC: Remove references to corgi and spitz from machine driver document
ASoC: Make SND_SOC_MX27VIS_AIC32X4 depend on I2C
ASoC: Fix dependency for SND_SOC_RAUMFELD and SND_PXA2XX_SOC_HX4700
ASoC: uda1380: Return proper error in uda1380_modinit failure path
ASoC: kirkwood: Make SND_KIRKWOOD_SOC_OPENRD and SND_KIRKWOOD_SOC_T5325 depend on I2C
ASoC: Mark WM8994 ADC muxes as virtual
ALSA: hda/realtek - Fix Oops in alc_mux_select()
ALSA: sis7019 - give slow codecs more time to reset
Linus Torvalds [Fri, 9 Dec 2011 16:07:24 +0000 (08:07 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Do no try to schedule task events if there are none
lockdep, kmemcheck: Annotate ->lock in lockdep_init_map()
perf header: Use event_name() to get an event name
perf stat: Failure with "Operation not supported"
Modify initialization of PCIe capability registers in Tsi721 mport driver:
- change Completion Timeout value to avoid unexpected data transfer
aborts during intensive traffic.
- replace hardcoded offset of PCIe capability block by making it use the
common function.
This patch is applicable to kernel versions starting from 3.2-rc1.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug fix for Tsi721 RapidIO mport driver: Tsi721 supports four RapidIO
mailboxes (MBOX0 - MBOX3) as defined by RapidIO specification. Mailbox
resources has to be properly reported to allow use of all available
mailboxes (initial version reports only MBOX0).
This patch is applicable to kernel versions staring from 3.2-rc1.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Thu, 8 Dec 2011 22:34:32 +0000 (14:34 -0800)]
procfs: do not overflow get_{idle,iowait}_time for nohz
Since commit a25cac5198d4 ("proc: Consider NO_HZ when printing idle and
iowait times") we are reporting idle/io_wait time also while a CPU is
tickless. We rely on get_{idle,iowait}_time functions to retrieve
proper data.
These functions, however, use usecs_to_cputime to translate micro
seconds time to cputime64_t. This is just an alias to usecs_to_jiffies
which reduces the data type from u64 to unsigned int and also checks
whether the given parameter overflows jiffies_to_usecs(MAX_JIFFY_OFFSET)
and returns MAX_JIFFY_OFFSET in that case.
When we overflow depends on CONFIG_HZ but especially for CONFIG_HZ_300
it is quite low (1431649781) so we are getting MAX_JIFFY_OFFSET for
>3000s! until we overflow unsigned int. Just for reference
CONFIG_HZ_100 has an overflow window around 20s, CONFIG_HZ_250 ~8s and
CONFIG_HZ_1000 ~2s.
This results in a bug when people saw [h]top going mad reporting 100%
CPU usage even though there was basically no CPU load. The reason was
simply that /proc/stat stopped reporting idle/io_wait changes (and
reported MAX_JIFFY_OFFSET) and so the only change happening was for user
system time.
Let's use nsecs_to_jiffies64 instead which doesn't reduce the precision
to 32b type and it is much more appropriate for cumulative time values
(unlike usecs_to_jiffies which intended for timeout calculations).
Signed-off-by: Michal Hocko <mhocko@suse.cz> Tested-by: Artem S. Tashkinov <t.artem@mailcity.com> Cc: Dave Jones <davej@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 8 Dec 2011 22:34:30 +0000 (14:34 -0800)]
mm: vmalloc: check for page allocation failure before vmlist insertion
Commit f5252e00 ("mm: avoid null pointer access in vm_struct via
/proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after
it is fully initialised. Unfortunately, it did not check that
__vmalloc_area_node() successfully populated the area. In the event of
allocation failure, the vmalloc area is freed but the pointer to freed
memory is inserted into the vmlist leading to a a crash later in
get_vmalloc_info().
This patch adds a check for ____vmalloc_area_node() failure within
__vmalloc_node_range. It does not use "goto fail" as in the previous
error path as a warning was already displayed by __vmalloc_area_node()
before it called vfree in its failure path.
Credit goes to Luciano Chavez for doing all the real work of identifying
exactly where the problem was.
Michal Hocko [Thu, 8 Dec 2011 22:34:27 +0000 (14:34 -0800)]
mm: Ensure that pfn_valid() is called once per pageblock when reserving pageblocks
setup_zone_migrate_reserve() expects that zone->start_pfn starts at
pageblock_nr_pages aligned pfn otherwise we could access beyond an
existing memblock resulting in the following panic if
CONFIG_HOLES_IN_ZONE is not configured and we do not check pfn_valid:
We crashed in pageblock_is_reserved() when accessing pfn 0xc0000 because
highstart_pfn = 0x36ffe.
The issue was introduced in 3.0-rc1 by 6d3163ce ("mm: check if any page
in a pageblock is reserved before marking it MIGRATE_RESERVE").
Make sure that start_pfn is always aligned to pageblock_nr_pages to
ensure that pfn_valid s always called at the start of each pageblock.
Architectures with holes in pageblocks will be correctly handled by
pfn_valid_within in pageblock_is_reserved.
Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Dang Bo <bdang@vmware.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Arve Hjnnevg <arve@android.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> [3.0+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Youquan Song [Thu, 8 Dec 2011 22:34:18 +0000 (14:34 -0800)]
thp: set compound tail page _count to zero
Commit 70b50f94f1644 ("mm: thp: tail page refcounting fix") keeps all
page_tail->_count zero at all times. But the current kernel does not
set page_tail->_count to zero if a 1GB page is utilized. So when an
IOMMU 1GB page is used by KVM, it wil result in a kernel oops because a
tail page's _count does not equal zero.
Youquan Song [Thu, 8 Dec 2011 22:34:16 +0000 (14:34 -0800)]
thp: add compound tail page _mapcount when mapped
With the 3.2-rc kernel, IOMMU 2M pages in KVM works. But when I tried
to use IOMMU 1GB pages in KVM, I encountered an oops and the 1GB page
failed to be used.
The root cause is that 1GB page allocation calls gup_huge_pud() while 2M
page calls gup_huge_pmd. If compound pages are used and the page is a
tail page, gup_huge_pmd() increases _mapcount to record tail page are
mapped while gup_huge_pud does not do that.
So when the mapped page is relesed, it will result in kernel oops
because the page is not marked mapped.
This patch add tail process for compound page in 1GB huge page which
keeps the same process as 2M page.
Peter Zijlstra [Thu, 8 Dec 2011 22:34:13 +0000 (14:34 -0800)]
printk: avoid double lock acquire
Commit 4f2a8d3cf5e ("printk: Fix console_sem vs logbuf_lock unlock race")
introduced another silly bug where we would want to acquire an already
held lock. Avoid this.
Reported-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
More players joined to memory cgroup developments and Johannes' great work
changed internal design of memory cgroup dramatically. And he will do
more works. Michal Hokko did many bug fixes and know memory cgroup very
well. Daisuke Nishimura helped us very much but he seems busy now.
Thanks to his works.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
khugepaged can sometimes cause suspend to fail, requiring that the user
retry the suspend operation.
Use wait_event_freezable_timeout() instead of
schedule_timeout_interruptible() to avoid missing freezer wakeups. A
try_to_freeze() would have been needed in the khugepaged_alloc_hugepage
tight loop too in case of the allocation failing repeatedly, and
wait_event_freezable_timeout will provide it too.
khugepaged would still freeze just fine by trying again the next minute
but it's better if it freezes immediately.
Reported-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Tested-by: Jiri Slaby <jslaby@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Cc: "Rafael J. Wysocki" <rjw@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A shrinker function can return -1, means that it cannot do anything
without a risk of deadlock. For example prune_super() does this if it
cannot grab a superblock refrence, even if nr_to_scan=0. Currently we
interpret this -1 as a ULONG_MAX size shrinker and evaluate `total_scan'
according to this. So the next time around this shrinker can cause
really big pressure. Let's skip such shrinkers instead.
Also make total_scan signed, otherwise the check (total_scan < 0) below
never works.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matt Fleming [Fri, 18 Nov 2011 13:09:11 +0000 (13:09 +0000)]
x86, efi: Calling __pa() with an ioremap()ed address is invalid
If we encounter an efi_memory_desc_t without EFI_MEMORY_WB set
in ->attribute we currently call set_memory_uc(), which in turn
calls __pa() on a potentially ioremap'd address.
On CONFIG_X86_32 this is invalid, resulting in the following
oops on some machines:
BUG: unable to handle kernel paging request at f7f22280
IP: [<c10257b9>] reserve_ram_pages_type+0x89/0x210
[...]
A better approach to this problem is to map the memory region
with the correct attributes from the start, instead of modifying
it after the fact. The uncached case can be handled by
ioremap_nocache() and the cached by ioremap_cache().
Despite first impressions, it's not possible to use
ioremap_cache() to map all cached memory regions on
CONFIG_X86_64 because EFI_RUNTIME_SERVICES_DATA regions really
don't like being mapped into the vmalloc space, as detailed in
the following bug report,
Therefore, we need to ensure that any EFI_RUNTIME_SERVICES_DATA
regions are covered by the direct kernel mapping table on
CONFIG_X86_64. To accomplish this we now map E820_RESERVED_EFI
regions via the direct kernel mapping with the initial call to
init_memory_mapping() in setup_arch(), whereas previously these
regions wouldn't be mapped if they were after the last E820_RAM
region until efi_ioremap() was called. Doing it this way allows
us to delete efi_ioremap() completely.
Signed-off-by: Matt Fleming <matt.fleming@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Huang Ying <huang.ying.caritas@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console-pimps.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
Jeff Layton [Fri, 2 Dec 2011 01:23:34 +0000 (20:23 -0500)]
cifs: check for NULL last_entry before calling cifs_save_resume_key
Prior to commit eaf35b1, cifs_save_resume_key had some NULL pointer
checks at the top. It turns out that at least one of those NULL
pointer checks is needed after all.
When the LastNameOffset in a FIND reply appears to be beyond the end of
the buffer, CIFSFindFirst and CIFSFindNext will set srch_inf.last_entry
to NULL. Since eaf35b1, the code will now oops in this situation.
Fix this by having the callers check for a NULL last entry pointer
before calling cifs_save_resume_key. No change is needed for the
call site in cifs_readdir as it's not reachable with a NULL
current_entry pointer.
Cc: stable@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Reported-by: Adam G. Metzler <adamgmetzler@gmail.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
Jeff Layton [Fri, 2 Dec 2011 01:22:41 +0000 (20:22 -0500)]
cifs: attempt to freeze while looping on a receive attempt
In the recent overhaul of the demultiplex thread receive path, I
neglected to ensure that we attempt to freeze on each pass through the
receive loop.
Reported-and-Tested-by: Woody Suwalski <terraluna977@gmail.com> Reported-and-Tested-by: Adam Williamson <awilliam@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
Linus Torvalds [Thu, 8 Dec 2011 21:18:59 +0000 (13:18 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: drop spin lock when memory alloc fails
Btrfs: check if the to-be-added device is writable
Btrfs: try cluster but don't advance in search list
Btrfs: try to allocate from cluster even at LOOP_NO_EMPTY_SIZE
Tetsuo Handa [Thu, 8 Dec 2011 12:24:06 +0000 (21:24 +0900)]
TOMOYO: Fix pathname handling of disconnected paths.
Current tomoyo_realpath_from_path() implementation returns strange pathname
when calculating pathname of a file which belongs to lazy unmounted tree.
Use local pathname rather than strange absolute pathname in that case.
Also, this patch fixes a regression by commit 02125a82 "fix apparmor
dereferencing potentially freed dentry, sanitize __d_path() API".
Mark Langsdorf [Fri, 18 Nov 2011 15:33:06 +0000 (16:33 +0100)]
x86, hpet: Immediately disable HPET timer 1 if rtc irq is masked
When HPET is operating in RTC mode, the TN_ENABLE bit on timer1
controls whether the HPET or the RTC delivers interrupts to irq8. When
the system goes into suspend, the RTC driver sends a signal to the
HPET driver so that the HPET releases control of irq8, allowing the
RTC to wake the system from suspend. The switchover is accomplished by
a write to the HPET configuration registers which currently only
occurs while servicing the HPET interrupt.
On some systems, I have seen the system suspend before an HPET
interrupt occurs, preventing the write to the HPET configuration
register and leaving the HPET in control of the irq8. As the HPET is
not active during suspend, it does not generate a wake signal and RTC
alarms do not work.
This patch forces the HPET driver to immediately transfer control of
the irq8 channel to the RTC instead of waiting until the next
interrupt event.
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com> Link: http://lkml.kernel.org/r/20111118153306.GB16319@alberich.amd.com Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org
Li Zefan [Thu, 8 Dec 2011 01:08:40 +0000 (20:08 -0500)]
Btrfs: check if the to-be-added device is writable
If we call ioctl(BTRFS_IOC_ADD_DEV) directly, we'll succeed in adding
a readonly device to a btrfs filesystem, and btrfs will write to
that device, emitting kernel errors:
[ 3109.833692] lost page write due to I/O error on loop2
[ 3109.833720] lost page write due to I/O error on loop2
...
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
Alexandre Oliva [Thu, 8 Dec 2011 01:08:40 +0000 (20:08 -0500)]
Btrfs: try cluster but don't advance in search list
When we find an existing cluster, we switch to its block group as the
current block group, possibly skipping multiple blocks in the process.
Furthermore, under heavy contention, multiple threads may fail to
allocate from a cluster and then release just-created clusters just to
proceed to create new ones in a different block group.
This patch tries to allocate from an existing cluster regardless of its
block group, and doesn't switch to that group, instead proceeding to
try to allocate a cluster from the group it was iterating before the
attempt.
Signed-off-by: Alexandre Oliva <oliva@lsd.ic.unicamp.br> Signed-off-by: Chris Mason <chris.mason@oracle.com>
NeilBrown [Thu, 8 Dec 2011 05:26:08 +0000 (16:26 +1100)]
md: ensure new badblocks are handled promptly.
When we mark blocks as bad we need them to be acknowledged by the
metadata handler promptly.
For an in-kernel metadata handler that was already being done. But
for an external metadata handler we need to alert it of the change by
sending a notification through the sysfs file. This adds that
notification.
NeilBrown [Thu, 8 Dec 2011 05:22:48 +0000 (16:22 +1100)]
md: bad blocks shouldn't cause a Blocked status on a Faulty device.
Once a device is marked Faulty the badblocks - whether acknowledged or
not - become irrelevant. So they shouldn't cause the device to be
marked as Blocked.
Without this patch, a process might write "-blocked" to clear the
Blocked status, but while that will correctly fail the device, it
won't remove the apparent 'blocked' status.
NeilBrown [Thu, 8 Dec 2011 04:49:46 +0000 (15:49 +1100)]
md: take a reference to mddev during sysfs access.
When we are accessing an mddev via sysfs we know that the
mddev cannot disappear because it has an embedded kobj which
is refcounted by sysfs.
And we also take the mddev_lock.
However this is not enough.
The final mddev_put could have been called and the
mddev_delayed_delete is waiting for sysfs to let go so it can destroy
the kobj and mddev.
In this state there are a lot of changes that should not be attempted.
To to guard against this we:
- initialise mddev->all_mddevs in on last put so the state can be
easily detected.
- in md_attr_show and md_attr_store, check ->all_mddevs under
all_mddevs_lock and mddev_get the mddev if it still appears to
be active.
This means that if we get to sysfs as the mddev is being deleted we
will get -EBUSY.
rdev_attr_store and rdev_attr_show are similar but already have
sufficient protection. They check that rdev->mddev still points to
mddev after taking mddev_lock. As this is cleared before delayed
removal which can only be requested under the mddev_lock, this
ensure the rdev and mddev are still alive.
NeilBrown [Thu, 8 Dec 2011 04:49:12 +0000 (15:49 +1100)]
md: refine interpretation of "hold_active == UNTIL_IOCTL".
We like md devices to disappear when they really are not needed.
However it is not possible to tell from the current state whether it
is needed or not. We can only tell from recent history of changes.
In particular immediately after we create an md device it looks very
similar to immediately after we have finished with it.
So we always preserve a newly created md device until something
significant happens. This state is stored in 'hold_active'.
The normal case is to keep it until an ioctl happens, as that will
normally either activate it, or explicitly de-activate it. If it
doesn't then it was probably created by mistake and it is now time to
get rid of it.
We can also modify an array via sysfs (instead of via ioctl) and we
currently treat any change via sysfs like an ioctl as a sign that if
it now isn't more active, it should be destroyed.
However this is not appropriate as changes made via sysfs are more
gradual so we should look for a more definitive change.
So this patch only clears 'hold_active' from UNTIL_IOCTL to clear when
the array_state is changed via sysfs. Other changes via sysfs
are ignored.
Linus Torvalds [Thu, 8 Dec 2011 02:18:27 +0000 (18:18 -0800)]
Merge branch '3.2-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
* '3.2-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (25 commits)
iscsi-target: Fix hex2bin warn_unused compile message
target: Don't return an error if disabling unsupported features
target/rd: fix or rewrite the copy routine
target/rd: simplify the page/offset computation
target: remove the unused se_dev_list
target/file: walk properly over sg list
target: remove unused struct fields
target: Fix page length in emulated INQUIRY VPD page 86h
target: Handle 0 correctly in transport_get_sectors_6()
target: Don't return an error status for 0-length READ and WRITE
iscsi-target: Use kmemdup rather than duplicating its implementation
iscsi-target: Add missing F_BIT for iscsi_tm_rsp
iscsi-target: Fix residual count hanlding + remove iscsi_cmd->residual_count
target: Reject SCSI data overflow for fabrics using transport_generic_map_mem_to_cmd
target: remove the unused t_task_pt_sgl and t_task_pt_sgl_num se_cmd fields
target: remove the t_tasks_bidi se_cmd field
target: remove the t_tasks_fua se_cmd field
target: remove the se_ordered_node se_cmd field
target: remove the se_obj_ptr and se_orig_obj_ptr se_cmd fields
target: Drop config_item_name usage in fabric TFO->free_wwn()
...
Alexandre Oliva [Thu, 8 Dec 2011 00:50:42 +0000 (19:50 -0500)]
Btrfs: try to allocate from cluster even at LOOP_NO_EMPTY_SIZE
If we reach LOOP_NO_EMPTY_SIZE, we won't even try to use a cluster that
others might have set up. Odds are that there won't be one, but if
someone else succeeded in setting it up, we might as well use it, even
if we don't try to set up a cluster again.
Signed-off-by: Alexandre Oliva <oliva@lsd.ic.unicamp.br> Signed-off-by: Chris Mason <chris.mason@oracle.com>
Alan Stern [Tue, 6 Dec 2011 22:24:52 +0000 (23:24 +0100)]
PM / Driver core: leave runtime PM enabled during system shutdown
Disabling all runtime PM during system shutdown turns out not to be a
good idea, because some devices may need to be woken up from a
low-power state at that time.
The whole point of disabling runtime PM for system shutdown was to
prevent untimely runtime-suspend method calls. This patch (as1504)
accomplishes the same result by incrementing the usage count for each
device and waiting for ongoing runtime-PM callbacks to finish. This
is what we already do during system suspend and hibernation, which
makes sense since the shutdown method is pretty much a legacy analog
of the pm->poweroff method.
This fixes a recent regression on some OMAP systems introduced by
commit af8db1508f2c9f3b6e633e2d2d906c6557c617f9 (PM / driver core:
disable device's runtime PM during shutdown).
Reported-and-tested-by: NeilBrown <neilb@suse.de> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Manuel Lauss [Sat, 19 Nov 2011 12:08:10 +0000 (13:08 +0100)]
spi/gpio: fix section mismatch warning
Fixes:
The function __devinit spi_gpio_probe() references
a function __init spi_gpio_alloc.isra.4().
If spi_gpio_alloc.isra.4 is only used by spi_gpio_probe then
annotate spi_gpio_alloc.isra.4 with a matching annotation.
[wsa: fix spi_gpio_request(), too]
Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Jiri Slaby [Wed, 7 Dec 2011 20:18:16 +0000 (21:18 +0100)]
spi/fsl-espi: disable CONFIG_SPI_FSL_ESPI=m build
When spi_fsl_espi is chosen to be built as a module, there is a build
error because we test only CONFIG_SPI_FSL_ESPI in declaration of
struct mpc8xxx_spi in drivers/spi/spi_fsl_lib.h. Also some called
functions are not exported.
So we forbid CONFIG_SPI_FSL_ESPI to be tristate here.
The error looks like:
drivers/spi/spi_fsl_espi.c: In function 'fsl_espi_bufs':
drivers/spi/spi_fsl_espi.c:232: error: 'struct mpc8xxx_spi' has no member named 'len'
...
Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Kumar Gala <galak@kernel.crashing.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Axel Lin [Thu, 24 Nov 2011 03:10:51 +0000 (11:10 +0800)]
spi/nuc900: Include linux/module.h
Include linux/module.h to fix below build error:
CC drivers/spi/spi-nuc900.o
drivers/spi/spi-nuc900.c:484: error: 'THIS_MODULE' undeclared here (not in a function)
drivers/spi/spi-nuc900.c:489: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-nuc900.c:489: warning: data definition has no type or storage class
drivers/spi/spi-nuc900.c:489: warning: type defaults to 'int' in declaration of 'MODULE_AUTHOR'
drivers/spi/spi-nuc900.c:489: warning: function declaration isn't a prototype
drivers/spi/spi-nuc900.c:490: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-nuc900.c:490: warning: data definition has no type or storage class
drivers/spi/spi-nuc900.c:490: warning: type defaults to 'int' in declaration of 'MODULE_DESCRIPTION'
drivers/spi/spi-nuc900.c:490: warning: function declaration isn't a prototype
drivers/spi/spi-nuc900.c:491: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-nuc900.c:491: warning: data definition has no type or storage class
drivers/spi/spi-nuc900.c:491: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE'
drivers/spi/spi-nuc900.c:491: warning: function declaration isn't a prototype
drivers/spi/spi-nuc900.c:492: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-nuc900.c:492: warning: data definition has no type or storage class
drivers/spi/spi-nuc900.c:492: warning: type defaults to 'int' in declaration of 'MODULE_ALIAS'
drivers/spi/spi-nuc900.c:492: warning: function declaration isn't a prototype
make[2]: *** [drivers/spi/spi-nuc900.o] Error 1
make[1]: *** [drivers/spi] Error 2
make: *** [drivers] Error 2
Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Gabor Juhos [Wed, 16 Nov 2011 19:01:43 +0000 (20:01 +0100)]
spi/ath79: fix compile error due to missing include
Whithout including 'linux/module.h' spi-ath79 driver fails to compile
with the these errors:
drivers/spi/spi-ath79.c:273:12: error: 'THIS_MODULE' undeclared here (not in a function)
drivers/spi/spi-ath79.c:278:20: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-ath79.c:278:1: warning: data definition has no type or storage class
drivers/spi/spi-ath79.c:278:1: warning: type defaults to 'int' in declaration of 'MODULE_DESCRIPTION'
drivers/spi/spi-ath79.c:278:20: warning: function declaration isn't a prototype
drivers/spi/spi-ath79.c:279:15: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-ath79.c:279:1: warning: data definition has no type or storage class
drivers/spi/spi-ath79.c:279:1: warning: type defaults to 'int' in declaration of 'MODULE_AUTHOR'
drivers/spi/spi-ath79.c:279:15: warning: function declaration isn't a prototype
drivers/spi/spi-ath79.c:280:16: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-ath79.c:280:1: warning: data definition has no type or storage class
drivers/spi/spi-ath79.c:280:1: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE'
drivers/spi/spi-ath79.c:280:16: warning: function declaration isn't a prototype
drivers/spi/spi-ath79.c:281:14: error: expected declaration specifiers or '...' before string constant
drivers/spi/spi-ath79.c:281:1: warning: data definition has no type or storage class
drivers/spi/spi-ath79.c:281:1: warning: type defaults to 'int' in declaration of 'MODULE_ALIAS'
drivers/spi/spi-ath79.c:281:14: warning: function declaration isn't a prototype
Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Anton Vorontsov [Tue, 6 Dec 2011 23:16:26 +0000 (03:16 +0400)]
of/irq: Get rid of NO_IRQ usage
PPC32/64 defines NO_IRQ to zero, so no problems expected.
ARM defines NO_IRQ to -1, but OF code relies on IRQ domains support,
which returns correct ('0') value in 'no irq' case. So everything
should be fine.
Other arches might break if some of their OF drivers rely on NO_IRQ
being not 0. If so, the drivers must be fixed, finally.
[ Rob Herring points out that microblaze should be fixed, and has posted
a patch for testing for that. - Linus ]
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Takashi Iwai [Wed, 7 Dec 2011 16:20:30 +0000 (17:20 +0100)]
ALSA: hda/realtek - Fix lost speaker volume controls
When there are the same or more number of HP pins are available, HP pins
are used as the primary outputs instead of the speaker pins. But, in
some cases (especially with ALC663 & co), some DACs are available only
with a later pin and it's assigned to a speaker, and since the driver
parses the pins from the lower NID, such a DAC was skipped eventually
without assignments. This resulted in a regression, the missing speaker
volume control in the new parser.
As a workaround for this, now the driver retries the pin->DAC mapping
again after restoring the speaker-pins as primary. This is still an ad
hoc fix, but it works so far for most of Realtek codecs.
Takashi Iwai [Wed, 7 Dec 2011 16:14:20 +0000 (17:14 +0100)]
ALSA: hda/realtek - Create "Bass Speaker" for two speaker pins
On systems with two speaker pins, the secondary speaker pin is mostly
assigned to a bass speaker instead of a surround. Thus it makes more
sense to rename the control properly.
Takashi Iwai [Wed, 7 Dec 2011 15:55:19 +0000 (16:55 +0100)]
ALSA: hda/realtek - Don't create extra controls with channel suffix
The multiple headphone or speaker pins are usually provided to
output the same stream unlike line-out jacks (which are supposed
to be multi-channel surrounds). Thus giving a mixer name like
"Headphone Surround" is rather confusing. Instead, when multiple
headphone volumes are available, use index with the same "Headphone"
name.
Linus Torvalds [Wed, 7 Dec 2011 16:20:01 +0000 (08:20 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
vmwgfx: Use kcalloc instead of kzalloc to allocate array
drm/i915: fix infinite recursion on unbind due to ilk vt-d w/a
drm/radeon/kms: fix return type for radeon_encoder_get_dp_bridge_encoder_id
Gleb Natapov [Tue, 22 Nov 2011 14:08:21 +0000 (16:08 +0200)]
perf: Do no try to schedule task events if there are none
perf_event_sched_in() shouldn't try to schedule task events if there
are none otherwise task's ctx->is_active will be set and will not be
cleared during sched_out. This will prevent newly added events from
being scheduled into the task context.
Fixes a boo-boo in commit 1d5f003f5a9 ("perf: Do not set task_ctx
pointer in cpuctx if there are no events in the context").
Thomas Meyer [Tue, 29 Nov 2011 21:08:00 +0000 (22:08 +0100)]
vmwgfx: Use kcalloc instead of kzalloc to allocate array
The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.
The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107
Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Reviewed-by: Jakob Bornecrantz <jakob@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
Daniel Vetter [Tue, 6 Dec 2011 11:12:33 +0000 (12:12 +0100)]
drm/i915: fix infinite recursion on unbind due to ilk vt-d w/a
The recursion loop goes retire_requests->unbind->gpu_idle->retire_reqeusts.
Every time we go through this we need a
- active object that can be retired
- and there are no other references to that object than the one from
the active list, so that it gets unbound and freed immediately.
Otherwise the recursion stops. So the recursion is only limited by the
number of objects that fit these requirements sitting in the active list
any time retire_request is called.
Issue exercised by tests/gem_unref_active_buffers from i-g-t.
There's been a decent bikeshed discussion whether it wouldn't be
better to pass around a flag, but imo this is o.k. for such a limited
case that only supports a w/a.
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Chris Wilson <chris@chris-wilson>
[ickle- we built better bikesheds, but this keeps the rain off for now] Tested-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
Al Viro [Mon, 5 Dec 2011 13:43:34 +0000 (08:43 -0500)]
fix apparmor dereferencing potentially freed dentry, sanitize __d_path() API
__d_path() API is asking for trouble and in case of apparmor d_namespace_path()
getting just that. The root cause is that when __d_path() misses the root
it had been told to look for, it stores the location of the most remote ancestor
in *root. Without grabbing references. Sure, at the moment of call it had
been pinned down by what we have in *path. And if we raced with umount -l, we
could have very well stopped at vfsmount/dentry that got freed as soon as
prepend_path() dropped vfsmount_lock.
It is safe to compare these pointers with pre-existing (and known to be still
alive) vfsmount and dentry, as long as all we are asking is "is it the same
address?". Dereferencing is not safe and apparmor ended up stepping into
that. d_namespace_path() really wants to examine the place where we stopped,
even if it's not connected to our namespace. As the result, it looked
at ->d_sb->s_magic of a dentry that might've been already freed by that point.
All other callers had been careful enough to avoid that, but it's really
a bad interface - it invites that kind of trouble.
The fix is fairly straightforward, even though it's bigger than I'd like:
* prepend_path() root argument becomes const.
* __d_path() is never called with NULL/NULL root. It was a kludge
to start with. Instead, we have an explicit function - d_absolute_root().
Same as __d_path(), except that it doesn't get root passed and stops where
it stops. apparmor and tomoyo are using it.
* __d_path() returns NULL on path outside of root. The main
caller is show_mountinfo() and that's precisely what we pass root for - to
skip those outside chroot jail. Those who don't want that can (and do)
use d_path().
* __d_path() root argument becomes const. Everyone agrees, I hope.
* apparmor does *NOT* try to use __d_path() or any of its variants
when it sees that path->mnt is an internal vfsmount. In that case it's
definitely not mounted anywhere and dentry_path() is exactly what we want
there. Handling of sysctl()-triggered weirdness is moved to that place.
* if apparmor is asked to do pathname relative to chroot jail
and __d_path() tells it we it's not in that jail, the sucker just calls
d_absolute_path() instead. That's the other remaining caller of __d_path(),
BTW.
* seq_path_root() does _NOT_ return -ENAMETOOLONG (it's stupid anyway -
the normal seq_file logics will take care of growing the buffer and redoing
the call of ->show() just fine). However, if it gets path not reachable
from root, it returns SEQ_SKIP. The only caller adjusted (i.e. stopped
ignoring the return value as it used to do).
Reviewed-by: John Johansen <john.johansen@canonical.com> ACKed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org
Apply the scheme used in log_regrant_write_log_space to wake up any other
threads waiting for log space before the newly added one to
log_regrant_write_log_space as well, and factor the code into readable
helpers. For each of the queues we have add two helpers:
- one to try to wake up all waiting threads. This helper will also be
usable by xfs_log_move_tail once we remove the current opportunistic
wakeups in it.
- one to sleep on t_wait until enough log space is available, loosely
modelled after Linux waitqueues.
And use them to reimplement the guts of log_regrant_write_log_space and
log_regrant_write_log_space. These two function now use one and the same
algorithm for waiting on log space instead of subtly different ones before,
with an option to completely unify them in the near future.
Also move the filesystem shutdown handling to the common caller given
that we had to touch it anyway.
Based on hard debugging and an earlier patch from
Chandra Seetharaman <sekharan@us.ibm.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chandra Seetharaman <sekharan@us.ibm.com> Tested-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
net: Silence seq_scale() unused warning
ipv4:correct description for tcp_max_syn_backlog
pasemi_mac: Fix building as module
netback: Fix alert message.
r8169: fix Rx index race between FIFO overflow recovery and NAPI handler.
r8169: Rx FIFO overflow fixes.
ipv4: Fix peer validation on cached lookup.
ipv4: make sure RTO_ONLINK is saved in routing cache
iwlwifi: change the default behavior of watchdog timer
iwlwifi: do not re-configure HT40 after associated
iwlagn: fix HW crypto for TX-only keys
Revert "mac80211: clear sta.drv_priv on reconfiguration"
mac80211: fill rate filter for internal scan requests
cfg80211: amend regulatory NULL dereference fix
cfg80211: fix race on init and driver registration
Linus Torvalds [Tue, 6 Dec 2011 19:54:33 +0000 (11:54 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ftrace: Fix hash record accounting bug
perf: Fix parsing of __print_flags() in TP_printk()
jump_label: jump_label_inc may return before the code is patched
ftrace: Remove force undef config value left for testing
tracing: Restore system filter behavior
tracing: fix event_subsystem ref counting