A successful write() to the "reset" sysfs attribute should return the
number of bytes written, not 0. Otherwise userspace (bash) retries the
write over and over again.
Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Michal Schmidt <mschmidt@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If a device doesn't support power management (pm_cap == 0) but it is
acpi_pci_power_manageable() because there is a _PS0 method declared for
it and _EJ0 is also declared for the slot then nobody is going to set
current_state = PCI_D0 for this device. This is what I think it is
happening:
pci_enable_device
|
__pci_enable_device_flags
/* here we do not set current_state because !pm_cap */
|
do_pci_enable_device
|
pci_set_power_state
|
__pci_start_power_transition
|
pci_platform_power_transition
/* platform_pci_power_manageable() calls acpi_pci_power_manageable that
* returns true */
|
platform_pci_set_power_state
/* acpi_pci_set_power_state gets called and does nothing because the
* acpi device has _EJ0, see the comment "If the ACPI device has _EJ0,
* ignore the device" */
at this point if we refer to the commit message that introduced the
comment above (10b3dcae0f275e2546e55303d64ddbb58cec7599), it is up to
the hotplug driver to set the state to D0.
However AFAICT the pci hotplug driver never does, in fact
drivers/pci/hotplug/acpiphp_glue.c:register_slot sets the slot flags to
(SLOT_ENABLED | SLOT_POWEREDON) but it does not set the pci device
current state to PCI_D0.
So my proposed fix is also to set current_state = PCI_D0 in
register_slot.
Comments are very welcome.
Up to 2.6.22, you could use remap_file_pages(2) on a tmpfs file or a
shared mapping of /dev/zero or a shared anonymous mapping. In 2.6.23 we
disabled it by default, but set VM_CAN_NONLINEAR to enable it on safe
mappings. We made sure to set it in shmem_mmap() for tmpfs files, but
missed it in shmem_zero_setup() for the others. Fix that at last.
The test program below will hang because io_getevents() uses
add_wait_queue_exclusive(), which means the wake_up() in io_destroy() only
wakes up one of the threads. Fix this by using wake_up_all() in the aio
code paths where we want to make sure no one gets stuck.
An integer overflow occurs in the calculation of RHlinear when the
relative humidity is greater than around 30%. The consequence is a subtle
(but noticeable) error in the resulting humidity measurement.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The latest binutils (2.21.0.20110302/Ubuntu) breaks the build
yet another time, under CONFIG_XEN=y due to a .size directive that
refers to a slightly differently named (hence, to the now very
strict and unforgiving assembler, non-existent) symbol.
[ mingo:
This unnecessary build breakage caused by new binutils
version 2.21 gets escallated back several kernel releases spanning
several years of Linux history, affecting over 130,000 upstream
kernel commits (!), on CONFIG_XEN=y 64-bit kernels (i.e. essentially
affecting all major Linux distro kernel configs).
Git annotate tells us that this slight debug symbol code mismatch
bug has been introduced in 2008 in commit 3d75e1b8:
Human reviewers almost never catch such small mismatches, and binutils
never even warned about it either.
This new binutils version thus breaks the Xen build on all upstream kernels
since v2.6.27, out of the blue.
This makes a straightforward Git bisection of all 64-bit Xen-enabled kernels
impossible on such binutils, for a bisection window of over hundred
thousand historic commits. (!)
This is a major fail on the side of binutils and binutils needs to turn
this show-stopper build failure into a warning ASAP. ]
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jan Beulich <jbeulich@novell.com> Cc: H.J. Lu <hjl.tools@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kees Cook <kees.cook@canonical.com>
LKML-Reference: <1299877178-26063-1-git-send-email-heukelum@fastmail.fm> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When trying to flash a machine via the update_flash command, Anton received the
following error:
Restarting system.
FLASH: kernel bug...flash list header addr above 4GB
The code in question has a comment that the flash list should be in
the kernel data and therefore under 4GB:
/* NOTE: the "first" block list is a global var with no data
* blocks in the kernel data segment. We do this because
* we want to ensure this block_list addr is under 4GB.
*/
Unfortunately the Kconfig option is marked tristate which means the variable
may not be in the kernel data and could be above 4GB.
Instead of relying on the data segment being below 4GB, use the static
data buffer allocated by the kernel for use by rtas. Since we don't
use the header struct directly anymore, convert it to a simple pointer.
Reported-By: Anton Blanchard <anton@samba.org> Signed-Off-By: Milton Miller <miltonm@bga.com> Tested-By: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When we are crashing, the crashing/primary CPU IPIs the secondaries to
turn off IRQs, go into real mode and wait in kexec_wait. While this
is happening, the primary tears down all the MMU maps. Unfortunately
the primary doesn't check to make sure the secondaries have entered
real mode before doing this.
On PHYP machines, the secondaries can take a long time shutting down
the IRQ controller as RTAS calls are need. These RTAS calls need to
be serialised which resilts in the secondaries contending in
lock_rtas() and hence taking a long time to shut down.
We've hit this on large POWER7 machines, where some secondaries are
still waiting in lock_rtas(), when the primary tears down the HPTEs.
This patch makes sure all secondaries are in real mode before the
primary tears down the MMU. It uses the new kexec_state entry in the
paca. It times out if the secondaries don't reach real mode after
10sec.
Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
During redetection of a SDIO card, a request for a new card RCA
was submitted to the card, but was then overwritten by the old RCA.
This caused the card to be deselected instead of selected when using
the incorrect RCA. This bug's been present since the "oldcard"
handling was introduced in 2.6.32.
Mike Galbraith reported finding a lockup ("perma-spin bug") where the
cpumask passed to smp_call_function_many was cleared by other cpu(s)
while a cpu was preparing its call_data block, resulting in no cpu to
clear the last ref and unlock the block.
Having cpus clear their bit asynchronously could be useful on a mask of
cpus that might have a translation context, or cpus that need a push to
complete an rcu window.
Instead of adding a BUG_ON and requiring yet another cpumask copy, just
detect the race and handle it.
Note: arch_send_call_function_ipi_mask must still handle an empty
cpumask because the data block is globally visible before the that arch
callback is made. And (obviously) there are no guarantees to which cpus
are notified if the mask is changed during the call; only cpus that were
online and had their mask bit set during the whole call are guaranteed
to be called.
Reported-by: Mike Galbraith <efault@gmx.de> Reported-by: Jan Beulich <JBeulich@novell.com> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove the call to tty_ldisc_flush() from the RESULT_NO_CARRIER
branch of isdn_tty_modem_result(), as already proposed in commit 00409bb045887ec5e7b9e351bc080c38ab6bfd33.
This avoids a "sleeping function called from invalid context" BUG
when the hardware driver calls the statcallb() callback with
command==ISDN_STAT_DHUP in atomic context, which in turn calls
isdn_tty_modem_result(RESULT_NO_CARRIER, ~), and from there,
tty_ldisc_flush() which may sleep.
Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
According to intel CPU manual, every time PGD entry is changed in i386 PAE
mode, we need do a full TLB flush. Current code follows this and there is
comment for this too in the code.
But current code misses the multi-threaded case. A changed page table
might be used by several CPUs, every such CPU should flush TLB. Usually
this isn't a problem, because we prepopulate all PGD entries at process
fork. But when the process does munmap and follows new mmap, this issue
will be triggered.
When it happens, some CPUs keep doing page faults:
Paul McKenney's review pointed out two problems with the barriers in the
2.6.38 update to the smp call function many code.
First, a barrier that would force the func and info members of data to
be visible before their consumption in the interrupt handler was
missing. This can be solved by adding a smp_wmb between setting the
func and info members and setting setting the cpumask; this will pair
with the existing and required smp_rmb ordering the cpumask read before
the read of refs. This placement avoids the need a second smp_rmb in
the interrupt handler which would be executed on each of the N cpus
executing the call request. (I was thinking this barrier was present
but was not).
Second, the previous write to refs (establishing the zero that we the
interrupt handler was testing from all cpus) was performed by a third
party cpu. This would invoke transitivity which, as a recient or
concurrent addition to memory-barriers.txt now explicitly states, would
require a full smp_mb().
However, we know the cpumask will only be set by one cpu (the data
owner) and any preivous iteration of the mask would have cleared by the
reading cpu. By redundantly writing refs to 0 on the owning cpu before
the smp_wmb, the write to refs will follow the same path as the writes
that set the cpumask, which in turn allows us to keep the barrier in the
interrupt handler a smp_rmb instead of promoting it to a smp_mb (which
will be be executed by N cpus for each of the possible M elements on the
list).
I moved and expanded the comment about our (ab)use of the rcu list
primitives for the concurrent walk earlier into this function. I
considered moving the first two paragraphs to the queue list head and
lock, but felt it would have been too disconected from the code.
Cc: Paul McKinney <paulmck@linux.vnet.ibm.com> Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Peter pointed out there was nothing preventing the list_del_rcu in
smp_call_function_interrupt from running before the list_add_rcu in
smp_call_function_many.
Fix this by not setting refs until we have gotten the lock for the list.
Take advantage of the wmb in list_add_rcu to save an explicit additional
one.
I tried to force this race with a udelay before the lock & list_add and
by mixing all 64 online cpus with just 3 random cpus in the mask, but
was unsuccessful. Still, inspection shows a valid race, and the fix is
a extension of the existing protection window in the current code.
Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When ext3_dx_add_entry() has to split an index node, it has to ensure that
name_len of dx_node's fake_dirent is also zero, because otherwise e2fsck
won't recognise it as an intermediate htree node and consider the htree to
be corrupted.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Events on POWER7 can roll back if a speculative event doesn't
eventually complete. Unfortunately in some rare cases they will
raise a performance monitor exception. We need to catch this to
ensure we reset the PMC. In all cases the PMC will be 256 or less
cycles from overflow.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20110309143842.6c22845e@kryten> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes a race in which the task->tk_callback() puts the rpc_task
to sleep, setting a new callback. Under certain circumstances, the current
code may end up executing the task->tk_action before it gets round to the
callback.
The use of blk_execute_rq_nowait() implies __blk_put_request() is needed
in stpg_endio() rather than blk_put_request() -- blk_finish_request() is
called with queue lock already held.
Signed-off-by: Joseph Gruher <joseph.r.gruher@intel.com> Signed-off-by: Ilgu Hong <ilgu.hong@promise.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit 280c73d ("PCI: centralize the capabilities code in
pci-sysfs.c") changed the initialisation of the "rom" and "vpd"
attributes, and made the failure path for the "vpd" attribute
incorrect. We must free the new attribute structure (attr), but
instead we currently free dev->vpd->attr. That will normally be NULL,
resulting in a memory leak, but it might be a stale pointer, resulting
in a double-free.
Some broken BIOSes on ICH4 chipset report an ACPI region which is in
conflict with legacy IDE ports when ACPI is disabled. Even though the
regions overlap, IDE ports are working correctly (we cannot find out
the decoding rules on chipsets).
So the only problem is the reported region itself, if we don't reserve
the region in the quirk everything works as expected.
This patch avoids reserving any quirk regions below PCIBIOS_MIN_IO
which is 0x1000. Some regions might be (and are by a fast google
query) below this border, but the only difference is that they won't
be reserved anymore. They should still work though the same as before.
The conflicts look like (1f.0 is bridge, 1f.1 is IDE ctrl):
pci 0000:00:1f.1: address space collision: [io 0x0170-0x0177] conflicts with 0000:00:1f.0 [io 0x0100-0x017f]
At 0x0100 a 128 bytes long ACPI region is reported in the quirk for
ICH4. ata_piix then fails to find disks because the IDE legacy ports
are zeroed:
ata_piix 0000:00:1f.1: device not available (can't reserve [io 0x0000-0x0007])
Per ICH4 and ICH6 specs, ACPI and GPIO regions are valid iff ACPI_EN
and GPIO_EN bits are set to 1. Add checks for these bits into the
quirks prior to the region creation.
If BIOS doesn't allocate resources for the SR-IOV BARs, zero the Flash
BAR and program the SR-IOV BARs to use the old Flash Memory Space.
Please refer to Intel 82576 Gigabit Ethernet Controller Datasheet
section 7.9.2.14.2 for details.
http://download.intel.com/design/network/datashts/82576_Datasheet.pdf
Signed-off-by: Yu Zhao <yu.zhao@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This quirk was added before SR-IOV was in production and now all machines that
originally had this issue alreayd have bios updates to correct the issue. The
quirk itself is no longer needed and in fact causes bugs if run. Remove it.
When the mux for digital mic is different from the mux for other mics,
the current auto-parser doesn't handle them in a right way but provides
only one mic. This patch fixes the issue.
The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12
bytes of uninitialized stack memory, because the fsxattr struct
declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero)
the 12-byte fsx_pad member before copying it back to the user. This
patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com> Cc: dann frazier <dannf@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan's commit 335f8514f200e63d689113d29cb7253a5c282967 introduced
.carrier_raised function in several drivers. That also means
tty_port_block_til_ready can now suspend the process trying to open the serial
port when Carrier Detect is low and put it into tty_port.open_wait queue. We
need to wake up the process when Carrier Detect goes high and trigger TTY
hangup when CD goes low.
Some of the devices do not report modem status line changes, or at least we
don't understand the status message, so for those we remove .carrier_raised
again.
Device ID removed 0x10C4/0x8149 for West Mountain Radio Computerized
Battery Analyzer. This device is actually based on a SiLabs C8051Fxxx,
see http://www.etheus.net/SiUSBXp_Linux_Driver for further info.
In the vhci_urb_dequeue() function the TCP connection is checked twice.
Each time when the TCP connection is closed the URB is unlinked and given
back. Remove the second attempt of unlinking and giving back of the URB completely.
This patch fixes the bug described at https://bugzilla.kernel.org/show_bug.cgi?id=24872 .
Signed-off-by: Márton Németh <nm127@freemail.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sctp_packet_config() is called when getting the packet ready
for appending of chunks. The function should not touch the
current state, since it's possible to ping-pong between two
transports when sending, and that can result packet corruption
followed by skb overlfow crash.
Reported-by: Thomas Dreibholz <dreibh@iem.uni-due.de> Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I may have an explanation for the LSI 1068 HBA hangs provoked by ATA
pass-through commands, in particular by smartctl.
First, my version of the symptoms. On an LSI SAS1068E B3 HBA running
01.29.00.00 firmware, with SATA disks, and with smartd running, I'm seeing
occasional task, bus, and host resets, some of which lead to hard faults of
the HBA requiring a reboot. Abusively looping the smartctl command,
# while true; do smartctl -a /dev/sdb > /dev/null; done
dramatically increases the frequency of these failures to nearly one per
minute. A high IO load through the HBA while looping smartctl seems to
improve the chance of a full scsi host reset or a non-recoverable hang.
I reduced what smartctl was doing down to a simple test case which
causes the hang with a single IO when pointed at the sd interface. See
the code at the bottom of this e-mail. It uses an SG_IO ioctl to issue
a single pass-through ATA identify device command. If the buffer
userspace gives for the read data has certain alignments, the task is
issued to the HBA but the HBA fails to respond. If run against the sg
interface, neither the test code nor smartctl causes a hang.
sd and sg handle the SG_IO ioctl slightly differently. Unless you
specifically set a flag to do direct IO, sg passes a buffer of its own,
which is page-aligned, to the block layer and later copies the result
into the userspace buffer regardless of its alignment. sd, on the other
hand, always does direct IO unless the userspace buffer fails an
alignment test at block/blk-map.c line 57, in which case a page-aligned
buffer is created and used for the transfer.
The alignment test currently checks for word-alignment, the default
setup by scsi_lib.c; therefore, userspace buffers of almost any
alignment are given directly to the HBA as DMA targets. The LSI 1068
hardware doesn't seem to like at least a couple of the alignments which
cross a page boundary (see the test code below). Curiously, many
page-boundary-crossing alignments do work just fine.
So, either the hardware has an bug handling certain alignments or the
hardware has a stricter alignment requirement than the driver is
advertising. If stricter alignment is required, then in no case should
misaligned buffers from userspace be allowed through without being
bounced or at least causing an error to be returned.
It seems the mptsas driver could use blk_queue_dma_alignment() to advertise
a stricter alignment requirement. If it does, sd does the right thing and
bounces misaligned buffers (see block/blk-map.c line 57). The following
patch to 2.6.34-rc5 makes my symptoms go away. I'm sure this is the wrong
place for this code, but it gets my idea across.
We have 32-bit variable overflow possibility when multiply in
task_times() and thread_group_times() functions. When the
overflow happens then the scaled utime value becomes erroneously
small and the scaled stime becomes i erroneously big.
It turns out that the setpgid() system call fails to enter an RCU
read-side critical section before doing a PID-to-task_struct translation.
This commit therefore does rcu_read_lock() before the translation, and
also does rcu_read_unlock() after the last use of the returned pointer.
Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pcpu_first/last_unit_cpu are used to track which cpu has the first and
last units assigned. This in turn is used to determine the span of a
chunk for man/unmap cache flushes and whether an address belongs to
the first chunk or not in per_cpu_ptr_to_phys().
When the number of possible CPUs isn't power of two, a chunk may
contain unassigned units towards the end of a chunk. The logic to
determine pcpu_last_unit_cpu was incorrect when there was an unused
unit at the end of a chunk. It failed to ignore the unused unit and
assigned the unused marker NR_CPUS to pcpu_last_unit_cpu.
This was discovered through kdump failure which was caused by
malfunctioning per_cpu_ptr_to_phys() on a kvm setup with 50 possible
CPUs by CAI Qian.
When allocating a page, the system uses NR_FREE_PAGES counters to
determine if watermarks would remain intact after the allocation was made.
This check is made without interrupts disabled or the zone lock held and
so is race-prone by nature. Unfortunately, when pages are being freed in
batch, the counters are updated before the pages are added on the list.
During this window, the counters are misleading as the pages do not exist
yet. When under significant pressure on systems with large numbers of
CPUs, it's possible for processes to make progress even though they should
have been stalled. This is particularly problematic if a number of the
processes are using GFP_ATOMIC as the min watermark can be accidentally
breached and in extreme cases, the system can livelock.
This patch updates the counters after the pages have been added to the
list. This makes the allocator more cautious with respect to preserving
the watermarks and mitigates livelock possibilities.
[akpm@linux-foundation.org: avoid modifying incoming args] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When under significant memory pressure, a process enters direct reclaim
and immediately afterwards tries to allocate a page. If it fails and no
further progress is made, it's possible the system will go OOM. However,
on systems with large amounts of memory, it's possible that a significant
number of pages are on per-cpu lists and inaccessible to the calling
process. This leads to a process entering direct reclaim more often than
it should increasing the pressure on the system and compounding the
problem.
This patch notes that if direct reclaim is making progress but allocations
are still failing that the system is already under heavy pressure. In
this case, it drains the per-cpu lists and tries the allocation a second
time before continuing.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ordinarily watermark checks are based on the vmstat NR_FREE_PAGES as it is
cheaper than scanning a number of lists. To avoid synchronization
overhead, counter deltas are maintained on a per-cpu basis and drained
both periodically and when the delta is above a threshold. On large CPU
systems, the difference between the estimated and real value of
NR_FREE_PAGES can be very high. If NR_FREE_PAGES is much higher than
number of real free page in buddy, the VM can allocate pages below min
watermark, at worst reducing the real number of pages to zero. Even if
the OOM killer kills some victim for freeing memory, it may not free
memory if the exit path requires a new page resulting in livelock.
This patch introduces a zone_page_state_snapshot() function (courtesy of
Christoph) that takes a slightly more accurate view of an arbitrary vmstat
counter. It is used to read NR_FREE_PAGES while kswapd is awake to avoid
the watermark being accidentally broken. The estimate is not perfect and
may result in cache line bounces but is expected to be lighter than the
IPI calls necessary to continually drain the per-cpu counters while kswapd
is awake.
Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership
of the parent process's session keyring whether or not the parent has a session
keyring [CVE-2010-2960].
If the system is using pam_keyinit then it mostly protected against this as all
processes derived from a login will have inherited the session keyring created
by pam_keyinit during the log in procedure.
To test this, pam_keyinit calls need to be commented out in /etc/pam.d/.
There's an protected access to the parent process's credentials in the middle
of keyctl_session_to_parent(). This results in the following RCU warning:
Tony's fix (f574c843191728d9407b766a027f779dcd27b272) has a small bug,
it incorrectly uses "r3" as a scratch register in the first of the two
unlock paths ... it is also inefficient. Optimize the fast path again.
Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When ia64 converted to using ticket locks, an inline implementation
of trylock/unlock in fsys.S was missed. This was not noticed because
in most circumstances it simply resulted in using the slow path because
the siglock was apparently not available (under old spinlock rules).
Problems occur when the ticket spinlock has value 0x0 (when first
initialised, or when it wraps around). At this point the fsys.S
code acquires the lock (changing the 0x0 to 0x1. If another process
attempts to get the lock at this point, it will change the value from
0x1 to 0x2 (using new ticket lock rules). Then the fsys.S code will
free the lock using old spinlock rules by writing 0x0 to it. From
here a variety of bad things can happen.
Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Functions set_fan_min() and set_fan_div() assume that the fan_div
values have already been read from the register. The driver currently
doesn't initialize them at load time, they are only set when function
via686a_update_device() is called. This means that set_fan_min() and
set_fan_div() misbehave if, for example, "sensors -s" is called
before any monitoring application (e.g. "sensors") is has been run.
Fix the problem by always initializing the fan_div values at device
bind time.
Hardware breakpoints can't be registered within pid namespaces
because tsk->pid is passed rather than the pid in the current
namespace.
(See https://bugzilla.kernel.org/show_bug.cgi?id=17281 )
This is a quick fix demonstrating the problem but is not the
best method of solving the problem since passing pids internally
is not the best way to avoid pid namespace bugs. Subsequent patches
will show a better solution.
Much thanks to Frederic Weisbecker <fweisbec@gmail.com> for doing
the bulk of the work finding this bug.
Reported-by: Robin Green <greenrd@greenrd.org> Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <f63454af09fb1915717251570423eb9ddd338340.1284407762.git.matthltc@us.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
id = fork();
if (id == 0) { sleep(1); exit(0); }
kill(id, SIGSTOP);
alarm(1);
waitid(P_PID, id, &infop, WCONTINUED);
return 0;
}
to call waitid() on a stopped process results in access to the child task's
credentials without the RCU read lock being held - which may be replaced in the
meantime - eliciting the following warning:
This is fixed by holding the RCU read lock in wait_task_continued() to ensure
that the task's current credentials aren't destroyed between us reading the
cred pointer and us reading the UID from those credentials.
Furthermore, protect wait_task_stopped() in the same way.
We don't need to keep holding the RCU read lock once we've read the UID from
the credentials as holding the RCU read lock doesn't stop the target task from
changing its creds under us - so the credentials may be outdated immediately
after we've read the pointer, lock or no lock.
Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The VIAFB_GET_INFO device ioctl allows unprivileged users to read 246
bytes of uninitialized stack memory, because the "reserved" member of
the viafb_ioctl_info struct declared on the stack is not altered or
zeroed before being copied back to the user. This patch takes care of
it.
The FBIOGET_VBLANK device ioctl allows unprivileged users to read 16 bytes
of uninitialized stack memory, because the "reserved" member of the
fb_vblank struct declared on the stack is not altered or zeroed before
being copied back to the user. This patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Cc: Thomas Winischhofer <thomas@winischhofer.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
These devices don't do any writeback but their device inodes still can get
dirty so mark bdi appropriately so that bdi code does the right thing and files
inodes to lists of bdi carrying the device inodes.
Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <jaxboe@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If ->open() and ->close() are called multiple times, the same napi structs
will be added to dev->napi_list multiple times, corrupting the dev->napi_list.
This causes free_netdev() to hang during rmmod.
We fix this by calling netif_napi_del() during ->close().
Also, bnx2_init_napi() must not be in the __devinit section since it is
called by ->open().
Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: Benjamin Li <benli@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The bnx2 driver calls netif_napi_add() for all the NAPI structs during
->probe() time but not all of them will be used if we're not in MSI-X
mode. This creates a problem for netpoll since it will poll all the
NAPI structs in the dev_list whether or not they are scheduled, resulting
in a crash when we access structure fields not initialized for that vector.
We fix it by moving the netif_napi_add() call to ->open() after the number
of IRQ vectors has been determined.
Signed-off-by: Benjamin Li <benli@broadcom.com> Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Tavis Ormandy pointed out that do_io_submit does not do proper bounds
checking on the passed-in iocb array:
if (unlikely(nr < 0))
return -EINVAL;
if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(iocbpp)))))
return -EFAULT; ^^^^^^^^^^^^^^^^^^
The attached patch checks for overflow, and if it is detected, the
number of iocbs submitted is scaled down to a number that will fit in
the long. This is an ok thing to do, as sys_io_submit is documented as
returning the number of iocbs submitted, so callers should handle a
return value of less than the 'nr' argument passed in.
When an endpoint stalls, we need to update the xHCI host's internal
dequeue pointer to move it past the stalled transfer. This includes
updating the cycle bit (TRB ownership bit) if we have moved the dequeue
pointer past a link TRB with the toggle cycle bit set.
When we're trying to find the new dequeue segment, find_trb_seg() is
supposed to keep track of whether we've passed any link TRBs with the
toggle cycle bit set. However, this while loop's body
Will never get executed if the ring only contains one segment.
find_trb_seg() will return immediately, without updating the new cycle
bit. Since find_trb_seg() has no idea where in the segment the TD that
stalled was, make the caller, xhci_find_new_dequeue_state(), check for
this special case and update the cycle bit accordingly.
This patch should be queued to kernels all the way back to 2.6.31.
The document says:
|2.1 Problem description
| When at least two USB devices are simultaneously running, it is observed that
| sometimes the INT corresponding to one of the USB devices stops occurring. This may
| be observed sometimes with USB-to-serial or USB-to-network devices.
| The problem is not noticed when only USB mass storage devices are running.
|2.2 Implication
| This issue is because of the clearing of the respective Done Map bit on reading the ATL
| PTD Done Map register when an INT is generated by another PTD completion, but is not
| found set on that read access. In this situation, the respective Done Map bit will remain
| reset and no further INT will be asserted so the data transfer corresponding to that USB
| device will stop.
|2.3 Workaround
| An SOF INT can be used instead of an ATL INT with polling on Done bits. A time-out can
| be implemented and if a certain Done bit is never set, verification of the PTD completion
| can be done by reading PTD contents (valid bit).
| This is a proven workaround implemented in software.
Russell King run into this with an USB-to-serial converter. This patch
implements his suggestion to enable the high frequent SOF interrupt only
at the time we have ATL packages queued. It goes even one step further
and enables the SOF interrupt only if we have more than one ATL packet
queued at the same time.
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I picked up a new DAK-780EX(professional digitl reverb/mix system),
which use CH341T chipset to communication with computer on 3/2011
and the CH341T's vendor code is 1a86
Looking up the CH341T's vendor and product id's I see:
1a86 QinHeng Electronics
5523 CH341 in serial mode, usb to serial port converter
CH341T,CH341 are the products of the same company, maybe
have some common hardware, and I test the ch341.c works
well with CH341T
There are few places where we are checking for macversion and revsions
before RTC is powered ON. However we are reading the macversion and
revisions only after RTC is powered ON and so both macversion and
revisions are actully zero and this leads to incorrect srev checks
Incorrect srev checks can cause registers to be configured wrongly and can
cause unexpected behavior. Fixing this seems to address the ASPM issue that
we have observed. The laptop becomes very slow and hangs mostly with ASPM L1
enabled without this fix.
fix this by reading the macversion and revisisons even before we start
using them. There is no reason why should we delay reading this info
until RTC is powered on as this is just a register information.
Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit 7f74f8f28a2bd9db9404f7d364e2097a0c42cc12
(x86 quirk: Fix polarity for IRQ0 pin2 override on SB800
systems) introduced a regression. It removed some SB600 specific
code to determine the revision ID without adapting a
corresponding revision ID check for SB600.
When processing a SIDR REQ, the ib_cm allocates a new cm_id. The
refcount of the cm_id is initialized to 1. However, cm_process_work
will decrement the refcount after invoking all callbacks. The result
is that the cm_id will end up with refcount set to 0 by the end of the
sidr req handler.
If a user tries to destroy the cm_id, the destruction will proceed,
under the incorrect assumption that no other threads are referencing
the cm_id. This can lead to a crash when the cm callback thread tries
to access the cm_id.
This problem was noticed as part of a larger investigation with kernel
crashes in the rdma_cm when running on a real time OS.
Signed-off-by: Sean Hefty <sean.hefty@intel.com> Acked-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
They were able to reproduce the crash multiple times with the
following details:
Crash seems to always happen on the:
mutex_unlock(&conn_id->handler_mutex);
as conn_id looks to have been freed during this code path.
An examination of the code shows that a race exists in the request
handlers. When a new connection request is received, the rdma_cm
allocates a new connection identifier. This identifier has a single
reference count on it. If a user calls rdma_destroy_id() from another
thread after receiving a callback, rdma_destroy_id will proceed to
destroy the id and free the associated memory. However, the request
handlers may still be in the process of running. When control returns
to the request handlers, they can attempt to access the newly created
identifiers.
Fix this by holding a reference on the newly created rdma_cm_id until
the request handler is through accessing it.
Signed-off-by: Sean Hefty <sean.hefty@intel.com> Acked-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Emit warning when "mem=nopentium" is specified on any arch other
than x86_32 (the only that arch supports it).
Signed-off-by: Kamal Mostafa <kamal@canonical.com> BugLink: http://bugs.launchpad.net/bugs/553464 Cc: Yinghai Lu <yinghai@kernel.org> Cc: Len Brown <len.brown@intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl>
LKML-Reference: <1296783486-23033-2-git-send-email-kamal@canonical.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Avoid removing all of memory and panicing when "mem={invalid}"
is specified, e.g. mem=blahblah, mem=0, or mem=nopentium (on
platforms other than x86_32).
Signed-off-by: Kamal Mostafa <kamal@canonical.com> BugLink: http://bugs.launchpad.net/bugs/553464 Cc: Yinghai Lu <yinghai@kernel.org> Cc: Len Brown <len.brown@intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl>
LKML-Reference: <1296783486-23033-1-git-send-email-kamal@canonical.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When the fuction graph tracer starts, it needs to make a special
stack for each task to save the real return values of the tasks.
All running tasks have this stack created, as well as any new
tasks.
On CPU hot plug, the new idle task will allocate a stack as well
when init_idle() is called. The problem is that cpu hotplug does
not create a new idle_task. Instead it uses the idle task that
existed when the cpu went down.
ftrace_graph_init_task() will add a new ret_stack to the task
that is given to it. Because a clone will make the task
have a stack of its parent it does not check if the task's
ret_stack is already NULL or not. When the CPU hotplug code
starts a CPU up again, it will allocate a new stack even
though one already existed for it.
The solution is to treat the idle_task specially. In fact, the
function_graph code already does, just not at init_idle().
Instead of using the ftrace_graph_init_task() for the idle task,
which that function expects the task to be a clone, have a
separate ftrace_graph_init_idle_task(). Also, we will create a
per_cpu ret_stack that is used by the idle task. When we call
ftrace_graph_init_idle_task() it will check if the idle task's
ret_stack is NULL, if it is, then it will assign it the per_cpu
ret_stack.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
mm_fault_error() should not execute oom-killer, if page fault
occurs in kernel space. E.g. in copy_from_user()/copy_to_user().
This would happen if we find ourselves in OOM on a
copy_to_user(), or a copy_from_user() which faults.
Without this patch, the kernels hangs up in copy_from_user(),
because OOM killer sends SIG_KILL to current process, but it
can't handle a signal while in syscall, then the kernel returns
to copy_from_user(), reexcute current command and provokes
page_fault again.
With this patch the kernel return -EFAULT from copy_from_user().
The code, which checks that page fault occurred in kernel space,
has been copied from do_sigbus().
This situation is handled by the same way on powerpc, xtensa,
tile, ...
When au1000_eth probes the MII bus for PHY address, if we do not set
au1000_eth platform data's phy_search_highest_address, the MII probing
logic will exit early and will assume a valid PHY is found at address 0.
For MTX-1, the PHY is at address 31, and without this patch, the link
detection/speed/duplex would not work correctly.
ata_qc_complete() contains special handling for certain commands. For
example, it schedules EH for device revalidation after certain
configurations are changed. These shouldn't be applied to EH
commands but they were.
In most cases, it doesn't cause an actual problem because EH doesn't
issue any command which would trigger special handling; however, ACPI
can issue such commands via _GTF which can cause weird interactions.
Restructure ata_qc_complete() such that EH commands are always passed
on to __ata_qc_complete().
stable: Please apply to -stable only after 2.6.38 is released.
In the following commit, we'll need to use the CMD() macro in order to
fix the initialisation of the sector_erase_cmd field. That requires the
local variable to be called 'cfi', so change it first in a simple patch.
Since a8f80e8ff94ecba629542d9b4b5f5a8ee3eb565c any process with
CAP_NET_ADMIN may load any module from /lib/modules/. This doesn't mean
that CAP_NET_ADMIN is a superset of CAP_SYS_MODULE as modules are
limited to /lib/modules/**. However, CAP_NET_ADMIN capability shouldn't
allow anybody load any module not related to networking.
This patch restricts an ability of autoloading modules to netdev modules
with explicit aliases. This fixes CVE-2011-1019.
Arnd Bergmann suggested to leave untouched the old pre-v2.6.32 behavior
of loading netdev modules by name (without any prefix) for processes
with CAP_SYS_MODULE to maintain the compatibility with network scripts
that use autoloading netdev modules by aliases like "eth0", "wlan0".
Currently there are only three users of the feature in the upstream
kernel: ipip, ip_gre and sit.
root@albatros:~# capsh --drop=$(seq -s, 0 11),$(seq -s, 13 34) --
root@albatros:~# grep Cap /proc/$$/status
CapInh: 0000000000000000
CapPrm: fffffff800001000
CapEff: fffffff800001000
CapBnd: fffffff800001000
root@albatros:~# modprobe xfs
FATAL: Error inserting xfs
(/lib/modules/2.6.38-rc6-00001-g2bf4ca3/kernel/fs/xfs/xfs.ko): Operation not permitted
root@albatros:~# lsmod | grep xfs
root@albatros:~# ifconfig xfs
xfs: error fetching interface information: Device not found
root@albatros:~# lsmod | grep xfs
root@albatros:~# lsmod | grep sit
root@albatros:~# ifconfig sit
sit: error fetching interface information: Device not found
root@albatros:~# lsmod | grep sit
root@albatros:~# ifconfig sit0
sit0 Link encap:IPv6-in-IPv4
NOARP MTU:1480 Metric:1
root@albatros:~# lsmod | grep sit
sit 10457 0
tunnel4 2957 1 sit
For CAP_SYS_MODULE module loading is still relaxed:
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Kees Cook <kees.cook@canonical.com> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch adds the pid filtering for the dib7000M demod. It also
corrects the pid filtering for the dib7700 based board. It should
prevent an oops, when using dib7700p based board.
I found that one of the 8168c chipsets (concretely XID 1c4000c0) starts
generating RxFIFO overflow errors. The result is an infinite loop in
interrupt handler as the RxFIFOOver is handled only for ...MAC_VER_11.
With the workaround everything goes fine.
Signed-off-by: Ivan Vecera <ivecera@redhat.com> Acked-by: Francois Romieu <romieu@fr.zoreil.com> Cc: Hayes <hayeswang@realtek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When CPU hotplug is used, some CPUs may be offline at the time a kexec is
performed. The subsequent kernel may expect these CPUs to be already running,
and will declare them stuck. On pseries, there's also a soft-offline (cede)
state that CPUs may be in; this can also cause problems as the kexeced kernel
may ask RTAS if they're online -- and RTAS would say they are. The CPU will
either appear stuck, or will cause a crash as we replace its cede loop beneath
it.
This patch kicks each present offline CPU awake before the kexec, so that
none are forever lost to these assumptions in the subsequent kernel.
Now, the behaviour is that all available CPUs that were offlined are now
online & usable after the kexec. This mimics the behaviour of a full reboot
(on which all CPUs will be restarted).
Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Kamalesh babulal <kamalesh@linux.vnet.ibm.com>
cc: Anton Blanchard <anton@samba.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Like many other places, we have to check that the array index is
within allowed limits, or otherwise, a kernel oops and other nastiness
can ensue when we access memory beyond the end of the array.
The problem goes back to v2.6.30-rc1~1372~1342~31 where nf_log_bind
was decoupled from nf_log_register.
Reported-by: Miguel Di Ciurcio Filho <miguel.filho@gmail.com>,
via irc.freenode.net/#netfilter Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently for kexec the PTE tear down on 1TB segment systems normally
requires 3 hcalls for each PTE removal. On a machine with 32GB of
memory it can take around a minute to remove all the PTEs.
This optimises the path so that we only remove PTEs that are valid.
It also uses the read 4 PTEs at once HCALL. For the common case where
a PTEs is invalid in a 1TB segment, this turns the 3 HCALLs per PTE
down to 1 HCALL per 4 PTEs.
This gives an > 10x speedup in kexec times on PHYP, taking a 32GB
machine from around 1 minute down to a few seconds.
Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Kamalesh babulal <kamalesh@linux.vnet.ibm.com>
cc: Anton Blanchard <anton@samba.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds plpar_pte_read_4_raw() which can be used read 4 PTEs from
PHYP at a time, while in real mode.
It also creates a new hcall9 which can be used in real mode. It's the
same as plpar_hcall9 but minus the tracing hcall statistics which may
require variables outside the RMO.
Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Kamalesh babulal <kamalesh@linux.vnet.ibm.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
IOMMU table initialized, virtual merging enabled
Interrupt 155954 (real) is invalid, disabling it.
Interrupt 155953 (real) is invalid, disabling it.
ie we took some spurious interrupts. default_machine_crash_shutdown tries
to disable all interrupt sources but uses chip->disable which maps to
the default action of:
static void default_disable(unsigned int irq)
{
}
If we use chip->shutdown, then we actually mask the IRQ:
We wrap the crash_shutdown_handles[] calls with longjmp/setjmp, so if any
of them fault we can recover. The problem is we add a hook to the debugger
fault handler hook which calls longjmp unconditionally.
This first part of kdump is run before we marshall the other CPUs, so there
is a very good chance some CPU on the box is going to page fault. And when
it does it hits the longjmp code and assumes the context of the oopsing CPU.
The machine gets very confused when it has 10 CPUs all with the same stack,
all thinking they have the same CPU id. I get even more confused trying
to debug it.
The patch below adds crash_shutdown_cpu and uses it to specify which cpu is
in the protected region. Since it can only be -1 or the oopsing CPU, we don't
need to use memory barriers since it is only valid on the local CPU - no other
CPU will ever see a value that matches it's local CPU id.
Eventually we should switch the order and marshall all CPUs before doing the
crash_shutdown_handles[] calls, but that is a bigger fix.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kamalesh babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On large machines we are running out of room below 256MB. In some cases we
only need to ensure the allocation is in the first segment, which may be
256MB or 1TB.
Add slb0_limit and use it to specify the upper limit for the irqstack and
emergency stacks.
On a large ppc64 box, this fixes a panic at boot when the crashkernel=
option is specified (previously we would run out of memory below 256MB).
Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Robert Swiecki reported a BUG_ON(page_mapped) from a fuzzer, punching
a hole with madvise(,, MADV_REMOVE). That path is under mutex, and
cannot be explained by lack of serialization in unmap_mapping_range().
Reviewing the code, I found one place where vm_truncate_count handling
should have been updated, when I switched at the last minute from one
way of managing the restart_addr to another: mremap move changes the
virtual addresses, so it ought to adjust the restart_addr.
But rather than exporting the notion of restart_addr from memory.c, or
converting to restart_pgoff throughout, simply reset vm_truncate_count
to 0 to force a rescan if mremap move races with preempted truncation.
We have no confirmation that this fixes Robert's BUG,
but it is a fix that's worth making anyway.
We have found a hardware erratum on 82599 hardware that can lead to
unpredictable behavior when Header Splitting mode is enabled. So
we are no longer enabling this feature on affected hardware.
Please see the 82599 Specification Update for more information.
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com> Tested-by: Stephen Ko <stephen.s.ko@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes a race pointed out by Dave Airlie where we don't take a buffer
object about to be destroyed off the LRU lists properly. It also fixes a rare
case where a buffer object could be destroyed in the middle of an
accelerated eviction.
The patch also adds a utility function that can be used to prematurely
release GPU memory space usage of an object waiting to be destroyed.
For example during eviction or swapout.
The above mentioned commit didn't queue the buffer on the delayed destroy
list under some rare circumstances. It also didn't completely honor the
remove_all parameter.
However the code in rxrpc_instantiate strips it away:
data += sizeof(kver);
datalen -= sizeof(kver);
Removing kif_version fixes my problem.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When we get oplock break notification we should set the appropriate
value of OplockLevel field in oplock break acknowledge according to
the oplock level held by the client in this time. As we only can have
level II oplock or no oplock in the case of oplock break, we should be
aware only about clientCanCacheRead field in cifsInodeInfo structure.
Also fix bug connected with wrong interpretation of OplockLevel field
during oplock break notification processing.
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
projects / karo-tx-linux.git / log