Gleb Natapov [Tue, 9 Jun 2009 12:56:28 +0000 (15:56 +0300)]
KVM: Break dependency between vcpu index in vcpus array and vcpu_id.
Archs are free to use vcpu_id as they see fit. For x86 it is used as
vcpu's apic id. New ioctl is added to configure boot vcpu id that was
assumed to be 0 till now.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Nitin A Kamble [Mon, 8 Jun 2009 18:34:16 +0000 (11:34 -0700)]
KVM: VMX: Support Unrestricted Guest feature
"Unrestricted Guest" feature is added in the VMX specification.
Intel Westmere and onwards processors will support this feature.
It allows kvm guests to run real mode and unpaged mode
code natively in the VMX mode when EPT is turned on. With the
unrestricted guest there is no need to emulate the guest real mode code
in the vm86 container or in the emulator. Also the guest big real mode
code works like native.
The attached patch enhances KVM to use the unrestricted guest feature
if available on the processor. It also adds a new kernel/module
parameter to disable the unrestricted guest feature at the boot time.
Signed-off-by: Nitin A Kamble <nitin.a.kamble@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Marcelo Tosatti [Thu, 4 Jun 2009 18:08:24 +0000 (15:08 -0300)]
KVM: switch irq injection/acking data structures to irq_lock
Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:
CPU A CPU B
kvm_vm_ioctl_deassign_dev_irq()
mutex_lock(&kvm->lock); worker_thread()
-> kvm_deassign_irq() -> kvm_assigned_dev_interrupt_work_handler()
-> deassign_host_irq() mutex_lock(&kvm->lock);
-> cancel_work_sync() [blocked]
[gleb: fix ia64 path]
Reported-by: Alex Williamson <alex.williamson@hp.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Thu, 4 Jun 2009 15:09:08 +0000 (18:09 +0300)]
KVM: Calculate available entries in coalesced mmio ring
Instead of checking whether we'll wrap around, calculate how many entries
are available, and check whether we have enough (just one) for the pending
mmio.
By itself, this doesn't change anything, but it paves the way for making
this function lockless.
Avi Kivity [Sun, 31 May 2009 15:41:29 +0000 (18:41 +0300)]
KVM: VMX: Simplify pdptr and cr3 management
Instead of reading the PDPTRs from memory after every exit (which is slow
and wrong, as the PDPTRs are stored on the cpu), sync the PDPTRs from
memory to the VMCS before entry, and from the VMCS to memory after exit.
Do the same for cr3.
Gregory Haskins [Mon, 1 Jun 2009 16:54:56 +0000 (12:54 -0400)]
KVM: do not register i8254 PIO regions until we are initialized
We currently publish the i8254 resources to the pio_bus before the devices
are fully initialized. Since we hold the pit_lock, its probably not
a real issue. But lets clean this up anyway.
Reported-by: Avi Kivity <avi@redhat.com> Signed-off-by: Gregory Haskins <ghaskins@novell.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Avi Kivity <avi@redhat.com>
Gregory Haskins [Mon, 1 Jun 2009 16:54:50 +0000 (12:54 -0400)]
KVM: cleanup io_device code
We modernize the io_device code so that we use container_of() instead of
dev->private, and move the vtable to a separate ops structure
(theoretically allows better caching for multiple instances of the same
ops structure)
Signed-off-by: Gregory Haskins <ghaskins@novell.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Avi Kivity <avi@redhat.com>
Gregory Haskins [Mon, 1 Jun 2009 16:54:45 +0000 (12:54 -0400)]
KVM: Clean up coalesced_mmio destruction
We invoke kfree() on a data member instead of the structure. This works today
because the kvm_io_device is the first element of the private structure, but
this could change in the future, so lets clean this up.
Signed-off-by: Gregory Haskins <ghaskins@novell.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Avi Kivity <avi@redhat.com>
WARNING: arch/powerpc/kvm/kvm-440.o(.text+0x1e8c): Section mismatch in reference from the function kvmppc_44x_exit() to the function .exit.text:kvmppc_booke_exit()
The function kvmppc_44x_exit() references a function in an exit section.
Often the function kvmppc_booke_exit() has valid usage outside the exit section
and the fix is to remove the __exit annotation of kvmppc_booke_exit.
Also add some __init annotations on obvious routines.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Avi Kivity <avi@redhat.com>
Changing s390 code in kvm_arch_vcpu_load/put come across this header
declarations. They are complete duplicates, not even useful forward
declarations as nothing using it is in between (maybe it was that in
the past).
This patch removes the two dispensable lines.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Sheng Yang [Thu, 30 Apr 2009 02:58:42 +0000 (10:58 +0800)]
KVM: No disable_irq for MSI/MSI-X interrupt on device assignment
Disable interrupt at interrupt handler and enable it when guest ack is for
the level triggered interrupt, to prevent reinjected interrupt. MSI/MSI-X don't
need it.
One possible problem is multiply same vector interrupt injected between irq
handler and scheduled work handler would be merged as one for MSI/MSI-X.
But AFAIK, the drivers handle it well.
The patch fixed the oplin card performance issue(MSI-X performance is half of
MSI/INTx).
Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Andre Przywara [Thu, 28 May 2009 09:56:31 +0000 (11:56 +0200)]
KVM: SVM: use explicit 64bit storage for sysenter values
Since AMD does not support sysenter in 64bit mode, the VMCB fields storing
the MSRs are truncated to 32bit upon VMRUN/#VMEXIT. So store the values
in a separate 64bit storage to avoid truncation.
[andre: fix amd->amd migration]
Signed-off-by: Christoph Egger <christoph.egger@amd.com> Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
This patch relocates the variables kvm-s390 uses to track guest mem addr/size.
As discussed dropping the variables at struct kvm_arch level allows to use the
common vcpu->request based mechanism to reload guest memory if e.g. changes
via set_memory_region.
The kick mechanism introduced in this series is used to ensure running vcpus
leave guest state to catch the update.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
If signal pending is true we exit without updating kvm_run, userspace
currently just does nothing and jumps to kvm_run again.
Since we did not set an exit_reason we might end up with a random one
(whatever was the last exit). Therefore it was possible to e.g. jump to
the psw position the last real interruption set.
Setting the INTR exit reason ensures that no old psw data is swapped
in on reentry.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: s390: infrastructure to kick vcpus out of guest state
To ensure vcpu's come out of guest context in certain cases this patch adds a
s390 specific way to kick them out of guest context. Currently it kicks them
out to rerun the vcpu_run path in the s390 code, but the mechanism itself is
expandable and with a new flag we could also add e.g. kicks to userspace etc.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Jan Kiszka [Thu, 14 May 2009 20:42:53 +0000 (22:42 +0200)]
KVM: Allow PIT emulation without speaker port
The in-kernel speaker emulation is only a dummy and also unneeded from
the performance point of view. Rather, it takes user space support to
generate sound output on the host, e.g. console beeps.
To allow this, introduce KVM_CREATE_PIT2 which controls in-kernel
speaker port emulation via a flag passed along the new IOCTL. It also
leaves room for future extensions of the PIT configuration interface.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Gregory Haskins [Wed, 20 May 2009 14:30:49 +0000 (10:30 -0400)]
KVM: irqfd
KVM provides a complete virtual system environment for guests, including
support for injecting interrupts modeled after the real exception/interrupt
facilities present on the native platform (such as the IDT on x86).
Virtual interrupts can come from a variety of sources (emulated devices,
pass-through devices, etc) but all must be injected to the guest via
the KVM infrastructure. This patch adds a new mechanism to inject a specific
interrupt to a guest using a decoupled eventfd mechnanism: Any legal signal
on the irqfd (using eventfd semantics from either userspace or kernel) will
translate into an injected interrupt in the guest at the next available
interrupt window.
Signed-off-by: Gregory Haskins <ghaskins@novell.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Use proper foo-y style list additions to cleanup all the conditionals,
move module selection after compound object selection and remove the
superflous comment.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Huang Ying [Mon, 11 May 2009 08:48:15 +0000 (16:48 +0800)]
KVM: Add MCE support
The related MSRs are emulated. MCE capability is exported via
extension KVM_CAP_MCE and ioctl KVM_X86_GET_MCE_CAP_SUPPORTED. A new
vcpu ioctl command KVM_X86_SETUP_MCE is used to setup MCE emulation
such as the mcg_cap. MCE is injected via vcpu ioctl command
KVM_X86_SET_MCE. Extended machine-check state (MCG_EXT_P) and CMCI are
not implemented.
Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
"This seems to generate /sys/block/$device/queue and its contents for
everyone who is using queues, not just for those queues that have a
non-NULL queue->request_fn."
Note that embedding a queue inside another object has always been
an illegal construct, since the queues are reference counted and
must persist until the last reference is dropped. So aoe was
always buggy in this respect (Jens).
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Bruno Premont <bonbons@linux-vserver.org> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
i915: disable interrupts before tearing down GEM state
Reinette Chatre reports a frozen system (with blinking keyboard LEDs)
when switching from graphics mode to the text console, or when
suspending (which does the same thing). With netconsole, the oops
turned out to be
BUG: unable to handle kernel NULL pointer dereference at 0000000000000084
IP: [<ffffffffa03ecaab>] i915_driver_irq_handler+0x26b/0xd20 [i915]
and it's due to the i915_gem.c code doing drm_irq_uninstall() after
having done i915_gem_idle(). And the i915_gem_idle() path will do
but if an i915 interrupt comes in after this stage, it may want to
access that hw_status_page, and gets the above NULL pointer dereference.
And since the NULL pointer dereference happens from within an interrupt,
and with the screen still in graphics mode, the common end result is
simply a silently hung machine.
Fix it by simply uninstalling the irq handler before idling rather than
after. Fixes
Zhenyu Wang [Tue, 8 Sep 2009 06:52:25 +0000 (14:52 +0800)]
drm/i915: fix mask bits setting
eDP is exclusive connector too, and add missing crtc_mask
setting for TV.
This fixes
http://bugzilla.kernel.org/show_bug.cgi?id=14139
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Reported-and-tested-by: Carlos R. Mafra <crmafra2@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
agp/intel: support for new chip variant of IGDNG mobile
drm/i915: Unref old_obj on get_fence_reg() error path
drm/i915: increase default latency constant (v2 w/comment)
Dave Airlie [Mon, 7 Sep 2009 05:26:19 +0000 (15:26 +1000)]
drm/radeon/kms: add LTE/GTE discard + rv515 two sided stencil register.
This adds some rv350+ register for LTE/GTE discard,
and enables the rv515 two sided stencil register.
It also disables the DEPTHXY_OFFSET register which
can be used to workaround the CS checker.
Moves rs690 to proper place in rs600 and uses correct
table on rs600.
breaks the build of the gianfar driver because "dev" is undefined in
this function. To quickly test rc9 I changed this to priv->ndev but I do
not know if this is the correct one.
--------------------
Signed-off-by: David S. Miller <davem@davemloft.net>
powerpc: Fix i8259 interrupt driver kernel crash on ML510
This patch fixes a null pointer exception caused by removal of
'ack()' for level interrupts in the Xilinx interrupt driver. A recent
change to the xilinx interrupt controller removed the ack hook for
level irqs.
Signed-off-by: Roderick Colenbrander <thunderbird2k@gmail.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
dm snapshot: fix on disk chunk size validation
dm exception store: split set_chunk_size
dm snapshot: fix header corruption race on invalidation
dm snapshot: refactor zero_disk_area to use chunk_io
dm log: userspace add luid to distinguish between concurrent log instances
dm raid1: do not allow log_failure variable to unset after being set
dm log: remove incorrect field from userspace table output
dm log: fix userspace status output
dm stripe: expose correct io hints
dm table: add more context to terse warning messages
dm table: fix queue_limit checking device iterator
dm snapshot: implement iterate devices
dm multipath: fix oops when request based io fails when no paths
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc64: Fix bootup with mcount in some configs.
sparc64: Kill spurious NMI watchdog triggers by increasing limit to 30 seconds.
Nicolas Pitre [Sat, 5 Sep 2009 04:25:37 +0000 (00:25 -0400)]
ext2: fix unbalanced kmap()/kunmap()
In ext2_rename(), dir_page is acquired through ext2_dotdot(). It is
then released through ext2_set_link() but only if old_dir != new_dir.
Failing that, the pkmap reference count is never decremented and the
page remains pinned forever. Repeat that a couple times with highmem
pages and all pkmap slots get exhausted, and every further kmap() calls
end up stalling on the pkmap_map_wait queue at which point the whole
system comes to a halt.
Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
ocfs2: ocfs2_write_begin_nolock() should handle len=0
ocfs2: invalidate dentry if its dentry_lock isn't initialized.
pty: don't limit the writes to 'pty_space()' inside 'pty_write()'
The whole write-room thing is something that is up to the _caller_ to
worry about, not the pty layer itself. The total buffer space will
still be limited by the buffering routines themselves, so there is no
advantage or need in having pty_write() artificially limit the size
somehow.
And what happened was that the caller (the n_tty line discipline, in
this case) may have verified that there is room for 2 bytes to be
written (for NL -> CRNL expansion), and it used to then do those writes
as two single-byte writes. And if the first byte written (CR) then
caused a new tty buffer to be allocated, pty_space() may have returned
zero when trying to write the second byte (LF), and then incorrectly
failed the write - leading to a lost newline character.
This should finally fix
http://bugzilla.kernel.org/show_bug.cgi?id=14015
Reported-by: Mikael Pettersson <mikpe@it.uu.se> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When translating CR to CRNL in the n_tty line discipline, we did it as
two tty_put_char() calls. Which works, but is stupid, and has caused
problems before too with bad interactions with the write_room() logic.
The generic USB serial driver had that problem, for example.
Now the pty layer had similar issues after being moved to the generic
tty buffering code (in commit d945cb9cce20ac7143c2de8d88b187f62db99bdc:
"pty: Rework the pty layer to use the normal buffering logic").
So stop doing the silly separate two writes, and do it as a single write
instead. That's what the n_tty layer already does for the space
expansion of tabs (XTABS), and it means that we'll now always have just
a single write for the CRNL to match the single 'tty_write_room()' test,
which hopefully means that the next time somebody screws up buffering,
it won't cause weeks of debugging.
But the root of the problem lies in the fact that do_execve() path calls
tracehook_report_exec() which can stop if the tracer sets PT_TRACE_EXEC.
The tracee must not sleep in TASK_TRACED holding this mutex. Even if we
remove ->cred_guard_mutex from mm_for_maps() and proc_pid_attr_write(),
another task doing PTRACE_ATTACH should not hang until it is killed or the
tracee resumes.
With this patch do_execve() does not use ->cred_guard_mutex directly and
we do not hold it throughout, instead:
- introduce prepare_bprm_creds() helper, it locks the mutex
and calls prepare_exec_creds() to initialize bprm->cred.
- install_exec_creds() drops the mutex after commit_creds(),
and thus before tracehook_report_exec()->ptrace_stop().
or, if exec fails,
free_bprm() drops this mutex when bprm->cred != NULL which
indicates install_exec_creds() was not called.
Reported-by: Tom Horsley <tom.horsley@att.net> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
page-allocator: always change pageblock ownership when anti-fragmentation is disabled
On low-memory systems, anti-fragmentation gets disabled as fragmentation
cannot be avoided on a sufficiently large boundary to be worthwhile. Once
disabled, there is a period of time when all the pageblocks are marked
MOVABLE and the expectation is that they get marked UNMOVABLE at each call
to __rmqueue_fallback().
However, when MAX_ORDER is large the pageblocks do not change ownership
because the normal criteria are not met. This has the effect of
prematurely breaking up too many large contiguous blocks. This is most
serious on NOMMU systems which depend on high-order allocations to boot.
This patch causes pageblocks to change ownership on every fallback when
anti-fragmentation is disabled. This prevents the large blocks being
prematurely broken up.
This is a fix to commit 49255c619fbd482d704289b5eb2795f8e3b7ff2e [page
allocator: move check for disabled anti-fragmentation out of fastpath] and
the problem affects 2.6.31-rc8.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Tested-by: Paul Mundt <lethal@linux-sh.org> Cc: David Howells <dhowells@redhat.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Sat, 5 Sep 2009 18:17:07 +0000 (11:17 -0700)]
nommu: fix error handling in do_mmap_pgoff()
Fix the error handling in do_mmap_pgoff(). If do_mmap_shared_file() or
do_mmap_private() fail, we jump to the error_put_region label at which
point we cann __put_nommu_region() on the region - but we haven't yet
added the region to the tree, and so __put_nommu_region() may BUG
because the region tree is empty or it may corrupt the region tree.
To get around this, we can afford to add the region to the region tree
before calling do_mmap_shared_file() or do_mmap_private() as we keep
nommu_region_sem write-locked, so no-one can race with us by seeing a
transient region.
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Mel Gorman <mel@csn.ul.ie> Acked-by: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cancel_delayed_work() has to use del_timer_sync() to guarantee the timer
function is not running after return. But most users doesn't actually
need this, and del_timer_sync() has problems: it is not useable from
interrupt, and it depends on every lock which could be taken from irq.
Introduce __cancel_delayed_work() which calls del_timer() instead.
The immediate reason for this patch is
http://bugzilla.kernel.org/show_bug.cgi?id=13757
but hopefully this helper makes sense anyway.
As for 13757 bug, actually we need requeue_delayed_work(), but its
semantics are not yet clear.
Merge this patch early to resolves cross-tree interdependencies between
input and infiniband.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stefan Richter [Thu, 3 Sep 2009 21:07:35 +0000 (23:07 +0200)]
firewire: sbp2: fix freeing of unallocated memory
If a target writes invalid status (typically status of a command that
already timed out), firewire-sbp2 attempts to put away an ORB that
doesn't exist. https://bugzilla.redhat.com/show_bug.cgi?id=519772
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Stefan Richter [Fri, 28 Aug 2009 11:26:03 +0000 (13:26 +0200)]
firewire: ohci: fix Ricoh R5C832, video reception
In dual-buffer DMA mode, no video frames are ever received from R5C832
by libdc1394. Fallback to packet-per-buffer DMA works reliably.
http://thread.gmane.org/gmane.linux.kernel.firewire.devel/13393/focus=13476
Reported-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Stefan Richter [Fri, 28 Aug 2009 11:25:15 +0000 (13:25 +0200)]
firewire: ohci: fix Agere FW643 and multiple cameras
An Agere FW643 OHCI 1.1 card works fine for video reception from one
camera but fails early if receiving from two cameras. After a short
while, no IR IRQ events occur and the context control register does not
react anymore. This happens regardless whether both IR DMA contexts are
dual-buffer or one is dual-buffer and the other packet-per-buffer.
This can be worked around by disabling dual buffer DMA mode entirely.
http://sourceforge.net/mailarchive/message.php?msg_name=4A7C0594.2020208%40gmail.com
(Reported by Samuel Audet.)
In another report (by Jonathan Cameron), an FW643 works OK with two
cameras in dual buffer mode. Whether this is due to different chip
revisions or different usage patterns (different video formats) is not
yet clear. However, as far as the current capabilities of
firewire-core's isochronous I/O interface are concerned, simply
switching off dual-buffer on non-working and working FW643s alike is not
a problem in practice. We only need to revisit this issue if we are
going to enhance the interface, e.g. so that applications can explicitly
choose modes.
Reported-by: Samuel Audet <samuel.audet@gmail.com> Reported-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
As David Moore noted, a previously correct sizeof() expression became
wrong since the commit changed its argument from an array to a pointer.
This resulted in an oops in ohci_cancel_packet in the shared workqueue
thread's context when an isochronous resource was to be freed.
Reported-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Fix some problems seen in the chunk size processing when activating a
pre-existing snapshot.
For a new snapshot, the chunk size can either be supplied by the creator
or a default value can be used. For an existing snapshot, the
chunk size in the snapshot header on disk should always be used.
If someone attempts to load an existing snapshot and has the 'default
chunk size' option set, the kernel uses its default value even when it
is incorrect for the snapshot being loaded. This patch ensures the
correct on-disk value is always used.
Secondly, when the code does use the chunk size stored on the disk it is
prudent to revalidate it, so the code can exit cleanly if it got
corrupted as happened in
https://bugzilla.redhat.com/show_bug.cgi?id=461506 .
dm snapshot: fix header corruption race on invalidation
If a persistent snapshot fills up, a race can corrupt the on-disk header
which causes a crash on any future attempt to activate the snapshot
(typically while booting). This patch fixes the race.
When the snapshot overflows, __invalidate_snapshot is called, which calls
snapshot store method drop_snapshot. It goes to persistent_drop_snapshot that
calls write_header. write_header constructs the new header in the "area"
location.
Concurrently, an existing kcopyd job may finish, call copy_callback
and commit_exception method, that goes to persistent_commit_exception.
persistent_commit_exception doesn't do locking, relying on the fact that
callbacks are single-threaded, but it can race with snapshot invalidation and
overwrite the header that is just being written while the snapshot is being
invalidated.
The result of this race is a corrupted header being written that can
lead to a crash on further reactivation (if chunk_size is zero in the
corrupted header).
The fix is to use separate memory areas for each.
See the bug: https://bugzilla.redhat.com/show_bug.cgi?id=461506
dm log: userspace add luid to distinguish between concurrent log instances
Device-mapper userspace logs (like the clustered log) are
identified by a universally unique identifier (UUID). This
identifier is used to associate requests from the kernel to
a specific log in userspace. The UUID must be unique everywhere,
since multiple machines may use this identifier when communicating
about a particular log, as is the case for cluster logs.
Sometimes, device-mapper/LVM may re-use a UUID. This is the
case during pvmoves, when moving from one segment of an LV
to another, or when resizing a mirror, etc. In these cases,
a new log is created with the same UUID and loaded in the
"inactive" slot. When a device-mapper "resume" is issued,
the "live" table is deactivated and the new "inactive" table
becomes "live". (The "inactive" table can also be removed
via a device-mapper 'clear' command.)
The above two issues were colliding. More than one log was being
created with the same UUID, and there was no way to distinguish
between them. So, sometimes the wrong log would be swapped
out during the exchange.
The solution is to create a locally unique identifier,
'luid', to go along with the UUID. This new identifier is used
to determine exactly which log is being referenced by the kernel
when the log exchange is made. The identifier is not
universally safe, but it does not need to be, since
create/destroy/suspend/resume operations are bound to a specific
machine; and these are the operations that make up the exchange.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm raid1: do not allow log_failure variable to unset after being set
This patch fixes a bug which was triggering a case where the primary leg
could not be changed on failure even when the mirror was in-sync.
The case involves the failure of the primary device along with
the transient failure of the log device. The problem is that
bios can be put on the 'failures' list (due to log failure)
before 'fail_mirror' is called due to the primary device failure.
Normally, this is fine, but if the log device failure is transient,
a subsequent iteration of the work thread, 'do_mirror', will
reset 'log_failure'. The 'do_failures' function then resets
the 'in_sync' variable when processing bios on the failures list.
The 'in_sync' variable is what is used to determine if the
primary device can be switched in the event of a failure. Since
this has been reset, the primary device is incorrectly assumed
to be not switchable.
The case has been seen in the cluster mirror context, where one
machine realizes the log device is dead before the other machines.
As the responsibilities of the server migrate from one node to
another (because the mirror is being reconfigured due to the failure),
the new server may think for a moment that the log device is fine -
thus resetting the 'log_failure' variable.
In any case, it is inappropiate for us to reset the 'log_failure'
variable. The above bug simply illustrates that it can actually
hurt us.
Cc: stable@kernel.org Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm log: remove incorrect field from userspace table output
The output of 'dmsetup table' includes an internal field that should not
be there. This patch removes it. To make the fix simpler, we first
reorder a constructor argument
The 'device size' argument is generated internally. Currently it is
placed as the last space-separated word of the constructor string.
However, we need to use a version of the string without this word, so we
move it to the beginning instead so it is trivial to skip past it.
We keep a copy of the arguments passed to userspace for creating a log,
just in case we need to resend them. These are the same arguments that
are desired in the STATUSTYPE_TABLE request, except for one. When
creating the userspace log, the userspace daemon must know the size of
the mirror, so that is added to the arguments given in the constructor
table. We were printing this extra argument out as well, which is a
mistake.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Fri, 4 Sep 2009 19:40:25 +0000 (20:40 +0100)]
dm stripe: expose correct io hints
Set sensible I/O hints for striped DM devices in the topology
infrastructure added for 2.6.31 for userspace tools to
obtain via sysfs.
Add .io_hints to 'struct target_type' to allow the I/O hints portion
(io_min and io_opt) of the 'struct queue_limits' to be set by each
target and implement this for dm-stripe.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>