* one is a workaround that will be removed in v3.5 with proper fix in the tip/x86 tree,
* the other is to fix drivers to load on PV (a previous patch made them only
load in PVonHVM mode).
The rest are just minor fixes in the various drivers and some cleanup in the
core code.
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Merge tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull xen fixes from Konrad Rzeszutek Wilk:
"Two fixes for regressions:
* one is a workaround that will be removed in v3.5 with proper fix in
the tip/x86 tree,
* the other is to fix drivers to load on PV (a previous patch made
them only load in PVonHVM mode).
The rest are just minor fixes in the various drivers and some cleanup
in the core code."
* tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pcifront: avoid pci_frontend_enable_msix() falsely returning success
xen/pciback: fix XEN_PCI_OP_enable_msix result
xen/smp: Remove unnecessary call to smp_processor_id()
xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries'
xen: only check xen_platform_pci_unplug if hvm
There is an extra and unnecessary call to smp_processor_id()
in cpu_bringup(). Remove it.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The above mentioned patch checks the IOAPIC and if it contains
-1, then it unmaps said IOAPIC. But under Xen we get this:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
IP: [<ffffffff8134e51f>] xen_irq_init+0x1f/0xb0
PGD 0
Oops: 0002 [#1] SMP
CPU 0
Modules linked in:
Pid: 1, comm: swapper/0 Not tainted 3.2.10-3.fc16.x86_64 #1 Dell Inc. Inspiron
1525 /0U990C
RIP: e030:[<ffffffff8134e51f>] [<ffffffff8134e51f>] xen_irq_init+0x1f/0xb0
RSP: e02b: ffff8800d42cbb70 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00000000ffffffef RCX: 0000000000000001
RDX: 0000000000000040 RSI: 00000000ffffffef RDI: 0000000000000001
RBP: ffff8800d42cbb80 R08: ffff8800d6400000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffef
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000010
FS: 0000000000000000(0000) GS:ffff8800df5fe000(0000) knlGS:0000000000000000
CS: e033 DS: 0000 ES: 0000 CR0:000000008005003b
CR2: 0000000000000040 CR3: 0000000001a05000 CR4: 0000000000002660
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper/0 (pid: 1, threadinfo ffff8800d42ca000, task ffff8800d42d0000)
Stack:
00000000ffffffef 0000000000000010 ffff8800d42cbbe0 ffffffff8134f157
ffffffff8100a9b2 ffffffff8182ffd1 00000000000000a0 00000000829e7384
0000000000000002 0000000000000010 00000000ffffffff 0000000000000000
Call Trace:
[<ffffffff8134f157>] xen_bind_pirq_gsi_to_irq+0x87/0x230
[<ffffffff8100a9b2>] ? check_events+0x12+0x20
[<ffffffff814bab42>] xen_register_pirq+0x82/0xe0
[<ffffffff814bac1a>] xen_register_gsi.part.2+0x4a/0xd0
[<ffffffff814bacc0>] acpi_register_gsi_xen+0x20/0x30
[<ffffffff8103036f>] acpi_register_gsi+0xf/0x20
[<ffffffff8131abdb>] acpi_pci_irq_enable+0x12e/0x202
[<ffffffff814bc849>] pcibios_enable_device+0x39/0x40
[<ffffffff812dc7ab>] do_pci_enable_device+0x4b/0x70
[<ffffffff812dc878>] __pci_enable_device_flags+0xa8/0xf0
[<ffffffff812dc8d3>] pci_enable_device+0x13/0x20
The reason we are dying is b/c the call acpi_get_override_irq() is used,
which returns the polarity and trigger for the IRQs. That function calls
mp_find_ioapics to get the 'struct ioapic' structure - which along with the
mp_irq[x] is used to figure out the default values and the polarity/trigger
overrides. Since the mp_find_ioapics now returns -1 [b/c the IOAPIC is filled
with 0xffffffff], the acpi_get_override_irq() stops trying to lookup in the
mp_irq[x] the proper INT_SRV_OVR and we can't install the SCI interrupt.
The proper fix for this is going in v3.5 and adds an x86_io_apic_ops
struct so that platforms can override it. But for v3.4 lets carry this
work-around. This patch does that by providing a slightly different variant
of the fake IOAPIC entries.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Pull DMA mapping branch from Marek Szyprowski:
"Short summary for the whole series:
A few limitations have been identified in the current dma-mapping
design and its implementations for various architectures. There exist
more than one function for allocating and freeing the buffers:
currently these 3 are used dma_{alloc, free}_coherent,
dma_{alloc,free}_writecombine, dma_{alloc,free}_noncoherent.
For most of the systems these calls are almost equivalent and can be
interchanged. For others, especially the truly non-coherent ones
(like ARM), the difference can be easily noticed in overall driver
performance. Sadly not all architectures provide implementations for
all of them, so the drivers might need to be adapted and cannot be
easily shared between different architectures. The provided patches
unify all these functions and hide the differences under the already
existing dma attributes concept. The thread with more references is
available here:
http://www.spinics.net/lists/linux-sh/msg09777.html
These patches are also a prerequisite for unifying DMA-mapping
implementation on ARM architecture with the common one provided by
dma_map_ops structure and extending it with IOMMU support. More
information is available in the following thread:
http://thread.gmane.org/gmane.linux.kernel.cross-arch/12819
More works on dma-mapping framework are planned, especially in the
area of buffer sharing and managing the shared mappings (together with
the recently introduced dma_buf interface: commit d15bd7ee44
"dma-buf: Introduce dma buffer sharing mechanism").
The patches in the current set introduce a new alloc/free methods
(with support for memory attributes) in dma_map_ops structure, which
will later replace dma_alloc_coherent and dma_alloc_writecombine
functions."
People finally started piping up with support for merging this, so I'm
merging it as the last of the pending stuff from the merge window.
Looks like pohmelfs is going to wait for 3.5 and more external support
for merging.
* 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
common: DMA-mapping: add NON-CONSISTENT attribute
common: DMA-mapping: add WRITE_COMBINE attribute
common: dma-mapping: introduce mmap method
common: dma-mapping: remove old alloc_coherent and free_coherent methods
Hexagon: adapt for dma_map_ops changes
Unicore32: adapt for dma_map_ops changes
Microblaze: adapt for dma_map_ops changes
SH: adapt for dma_map_ops changes
Alpha: adapt for dma_map_ops changes
SPARC: adapt for dma_map_ops changes
PowerPC: adapt for dma_map_ops changes
MIPS: adapt for dma_map_ops changes
X86 & IA64: adapt for dma_map_ops changes
common: dma-mapping: introduce generic alloc() and free() methods
Adapt core x86 and IA64 architecture code for dma_map_ops changes: replace
alloc/free_coherent with generic alloc/free methods.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
[removed swiotlb related changes and replaced it with wrappers,
merged with IA64 patch to avoid inter-patch dependences in intel-iommu code]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Tony Luck <tony.luck@intel.com>
* Add fast-EOI acking of interrupts (clear a bit instead of hypercall)
And bug-fixes:
* Fix CPU bring-up code missing a call to notify other subsystems.
* Fix reading /sys/hypervisor even if PVonHVM drivers are not loaded.
* In Xen ACPI processor driver: remove too verbose WARN messages, fix up
the Kconfig dependency to be a module by default, and add dependency on
CPU_FREQ.
* Disable CPU frequency drivers from loading when booting under Xen
(as we want the Xen ACPI processor to be used instead).
* Cleanups in tmem code.
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Merge tag 'stable/for-linus-3.4-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull more xen updates from Konrad Rzeszutek Wilk:
"One tiny feature that accidentally got lost in the initial git pull:
* Add fast-EOI acking of interrupts (clear a bit instead of
hypercall)
And bug-fixes:
* Fix CPU bring-up code missing a call to notify other subsystems.
* Fix reading /sys/hypervisor even if PVonHVM drivers are not loaded.
* In Xen ACPI processor driver: remove too verbose WARN messages, fix
up the Kconfig dependency to be a module by default, and add
dependency on CPU_FREQ.
* Disable CPU frequency drivers from loading when booting under Xen
(as we want the Xen ACPI processor to be used instead).
* Cleanups in tmem code."
* tag 'stable/for-linus-3.4-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/acpi: Fix Kconfig dependency on CPU_FREQ
xen: initialize platform-pci even if xen_emul_unplug=never
xen/smp: Fix bringup bug in AP code.
xen/acpi: Remove the WARN's as they just create noise.
xen/tmem: cleanup
xen: support pirq_eoi_map
xen/acpi-processor: Do not depend on CPU frequency scaling drivers.
xen/cpufreq: Disable the cpu frequency scaling drivers from loading.
provide disable_cpufreq() function to disable the API.
- PV multiconsole support, so that there can be hvc1, hvc2, etc;
- P-state and C-state power management driver that uploads said
power management data to the hypervisor. It also inhibits cpufreq
scaling drivers to load so that only the hypervisor can make power
management decisions - fixing a weird perf bug.
- Function Level Reset (FLR) support in the Xen PCI backend.
Fixes:
- Kconfig dependencies for Xen PV keyboard and video
- Compile warnings and constify fixes
- Change over to use percpu_xxx instead of this_cpu_xxx
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Merge tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull xen updates from Konrad Rzeszutek Wilk:
"which has three neat features:
- PV multiconsole support, so that there can be hvc1, hvc2, etc; This
can be used in HVM and in PV mode.
- P-state and C-state power management driver that uploads said power
management data to the hypervisor. It also inhibits cpufreq
scaling drivers to load so that only the hypervisor can make power
management decisions - fixing a weird perf bug.
There is one thing in the Kconfig that you won't like: "default y
if (X86_ACPI_CPUFREQ = y || X86_POWERNOW_K8 = y)" (note, that it
all depends on CONFIG_XEN which depends on CONFIG_PARAVIRT which by
default is off). I've a fix to convert that boolean expression
into "default m" which I am going to post after the cpufreq git
pull - as the two patches to make this work depend on a fix in Dave
Jones's tree.
- Function Level Reset (FLR) support in the Xen PCI backend.
Fixes:
- Kconfig dependencies for Xen PV keyboard and video
- Compile warnings and constify fixes
- Change over to use percpu_xxx instead of this_cpu_xxx"
Fix up trivial conflicts in drivers/tty/hvc/hvc_xen.c due to changes to
a removed commit.
* tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen kconfig: relax INPUT_XEN_KBDDEV_FRONTEND deps
xen/acpi-processor: C and P-state driver that uploads said data to hypervisor.
xen: constify all instances of "struct attribute_group"
xen/xenbus: ignore console/0
hvc_xen: introduce HVC_XEN_FRONTEND
hvc_xen: implement multiconsole support
hvc_xen: support PV on HVM consoles
xenbus: don't free other end details too early
xen/enlighten: Expose MWAIT and MWAIT_LEAF if hypervisor OKs it.
xen/setup/pm/acpi: Remove the call to boot_option_idle_override.
xenbus: address compiler warnings
xen: use this_cpu_xxx replace percpu_xxx funcs
xen/pciback: Support pci_reset_function, aka FLR or D3 support.
pci: Introduce __pci_reset_function_locked to be used when holding device_lock.
xen: Utilize the restore_msi_irqs hook.
The CPU hotplug code has now a callback to help bring up the CPU.
Without the call we end up getting:
BUG: soft lockup - CPU#0 stuck for 29s! [migration/0:6]
Modules linked in:
CPU ] Pid: 6, comm: migration/0 Not tainted 3.3.0upstream-01180-ged378a5 #1 Dell Inc. PowerEdge T105 /0RR825
RIP: e030:[<ffffffff810d3b8b>] [<ffffffff810d3b8b>] stop_machine_cpu_stop+0x7b/0xf0
RSP: e02b:ffff8800ceaabdb0 EFLAGS: 00000293
.. snip..
Call Trace:
[<ffffffff810d3b10>] ? stop_one_cpu_nowait+0x50/0x50
[<ffffffff810d3841>] cpu_stopper_thread+0xf1/0x1c0
[<ffffffff815a9776>] ? __schedule+0x3c6/0x760
[<ffffffff815aa749>] ? _raw_spin_unlock_irqrestore+0x19/0x30
[<ffffffff810d3750>] ? res_counter_charge+0x150/0x150
[<ffffffff8108dc76>] kthread+0x96/0xa0
[<ffffffff815b27e4>] kernel_thread_helper+0x4/0x10
[<ffffffff815aacbc>] ? retint_restore_ar
Thix fixes it.
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
By using the functionality provided by "[CPUFREQ]: provide
disable_cpuidle() function to disable the API."
Under the Xen hypervisor we do not want the initial domain to exercise
the cpufreq scaling drivers. This is b/c the Xen hypervisor is
in charge of doing this as well and we can end up with both the
Linux kernel and the hypervisor trying to change the P-states
leading to weird performance issues.
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Fix compile error spotted by Benjamin Schweikert <b.schweikert@googlemail.com>]
For the hypervisor to take advantage of the MWAIT support it needs
to extract from the ACPI _CST the register address. But the
hypervisor does not have the support to parse DSDT so it relies on
the initial domain (dom0) to parse the ACPI Power Management information
and push it up to the hypervisor. The pushing of the data is done
by the processor_harveset_xen module which parses the information that
the ACPI parser has graciously exposed in 'struct acpi_processor'.
For the ACPI parser to also expose the Cx states for MWAIT, we need
to expose the MWAIT capability (leaf 1). Furthermore we also need to
expose the MWAIT_LEAF capability (leaf 5) for cstate.c to properly
function.
The hypervisor could expose these flags when it traps the XEN_EMULATE_PREFIX
operations, but it can't do it since it needs to be backwards compatible.
Instead we choose to use the native CPUID to figure out if the MWAIT
capability exists and use the XEN_SET_PDC query hypercall to figure out
if the hypervisor wants us to expose the MWAIT_LEAF capability or not.
Note: The XEN_SET_PDC query was implemented in c/s 23783:
"ACPI: add _PDC input override mechanism".
With this in place, instead of
C3 ACPI IOPORT 415
we get now
C3:ACPI FFH INTEL MWAIT 0x20
Note: The cpu_idle which would be calling the mwait variants for idling
never gets set b/c we set the default pm_idle to be the hypercall variant.
Acked-by: Jan Beulich <JBeulich@suse.com>
[v2: Fix missing header file include and #ifdef]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We needed that call in the past to force the kernel to use
default_idle (which called safe_halt, which called xen_safe_halt).
But set_pm_idle_to_default() does now that, so there is no need
to use this boot option operand.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[Pls also look at https://lkml.org/lkml/2012/2/10/228]
Using of PAT to change pages from WB to WC works quite nicely.
Changing it back to WB - not so much. The crux of the matter is
that the code that does this (__page_change_att_set_clr) has only
limited information so when it tries to the change it gets
the "raw" unfiltered information instead of the properly filtered one -
and the "raw" one tell it that PSE bit is on (while infact it
is not). As a result when the PTE is set to be WB from WC, we get
tons of:
:WARNING: at arch/x86/xen/mmu.c:475 xen_make_pte+0x67/0xa0()
:Hardware name: HP xw4400 Workstation
.. snip..
:Pid: 27, comm: kswapd0 Tainted: G W 3.2.2-1.fc16.x86_64 #1
:Call Trace:
: [<ffffffff8106dd1f>] warn_slowpath_common+0x7f/0xc0
: [<ffffffff8106dd7a>] warn_slowpath_null+0x1a/0x20
: [<ffffffff81005a17>] xen_make_pte+0x67/0xa0
: [<ffffffff810051bd>] __raw_callee_save_xen_make_pte+0x11/0x1e
: [<ffffffff81040e15>] ? __change_page_attr_set_clr+0x9d5/0xc00
: [<ffffffff8114c2e8>] ? __purge_vmap_area_lazy+0x158/0x1d0
: [<ffffffff8114cca5>] ? vm_unmap_aliases+0x175/0x190
: [<ffffffff81041168>] change_page_attr_set_clr+0x128/0x4c0
: [<ffffffff81041542>] set_pages_array_wb+0x42/0xa0
: [<ffffffff8100a9b2>] ? check_events+0x12/0x20
: [<ffffffffa0074d4c>] ttm_pages_put+0x1c/0x70 [ttm]
: [<ffffffffa0074e98>] ttm_page_pool_free+0xf8/0x180 [ttm]
: [<ffffffffa0074f78>] ttm_pool_mm_shrink+0x58/0x90 [ttm]
: [<ffffffff8112ba04>] shrink_slab+0x154/0x310
: [<ffffffff8112f17a>] balance_pgdat+0x4fa/0x6c0
: [<ffffffff8112f4b8>] kswapd+0x178/0x3d0
: [<ffffffff815df134>] ? __schedule+0x3d4/0x8c0
: [<ffffffff81090410>] ? remove_wait_queue+0x50/0x50
: [<ffffffff8112f340>] ? balance_pgdat+0x6c0/0x6c0
: [<ffffffff8108fb6c>] kthread+0x8c/0xa0
for every page. The proper fix for this is has been posted
and is https://lkml.org/lkml/2012/2/10/228
"x86/cpa: Use pte_attrs instead of pte_flags on CPA/set_p.._wb/wc operations."
along with a detailed description of the problem and solution.
But since that posting has gone nowhere I am proposing
this band-aid solution so that at least users don't get
the page corruption (the pages that are WC don't get changed to WB
and end up being recycled for filesystem or other things causing
mysterious crashes).
The negative impact of this patch is that users of WC flag
(which are InfiniBand, radeon, nouveau drivers) won't be able
to set that flag - so they are going to see performance degradation.
But stability is more important here.
Fixes RH BZ# 742032, 787403, and 745574
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
commit 7347b4082e "xen: Allow
unprivileged Xen domains to create iomap pages" added a redundant
line in the early bootup code to filter out the PTE. That
filtering is already done a bit earlier so this extra processing
is not required.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When a user offlines a VCPU and then onlines it, we get:
NMI watchdog disabled (cpu2): hardware events not enabled
BUG: scheduling while atomic: swapper/2/0/0x00000002
Modules linked in: dm_multipath dm_mod xen_evtchn iscsi_boot_sysfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi scsi_mod libcrc32c crc32c radeon fbco
ttm bitblit softcursor drm_kms_helper xen_blkfront xen_netfront xen_fbfront fb_sys_fops sysimgblt sysfillrect syscopyarea xen_kbdfront xenfs [last unloaded:
Pid: 0, comm: swapper/2 Tainted: G O 3.2.0phase15.1-00003-gd6f7f5b-dirty #4
Call Trace:
[<ffffffff81070571>] __schedule_bug+0x61/0x70
[<ffffffff8158eb78>] __schedule+0x798/0x850
[<ffffffff8158ed6a>] schedule+0x3a/0x50
[<ffffffff810349be>] cpu_idle+0xbe/0xe0
[<ffffffff81583599>] cpu_bringup_and_idle+0xe/0x10
The reason for this should be obvious from this call-chain:
cpu_bringup_and_idle:
\- cpu_bringup
| \-[preempt_disable]
|
|- cpu_idle
\- play_dead [assuming the user offlined the VCPU]
| \
| +- (xen_play_dead)
| \- HYPERVISOR_VCPU_off [so VCPU is dead, once user
| | onlines it starts from here]
| \- cpu_bringup [preempt_disable]
|
+- preempt_enable_no_reschedule()
+- schedule()
\- preempt_enable()
So we have two preempt_disble() and one preempt_enable(). Calling
preempt_enable() after the cpu_bringup() in the xen_play_dead
fixes the imbalance.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* commit 'v3.3-rc1': (9775 commits)
Linux 3.3-rc1
x86, syscall: Need __ARCH_WANT_SYS_IPC for 32 bits
qnx4: don't leak ->BitMap on late failure exits
qnx4: reduce the insane nesting in qnx4_checkroot()
qnx4: di_fname is an array, for crying out loud...
KEYS: Permit key_serial() to be called with a const key pointer
keys: fix user_defined key sparse messages
ima: fix cred sparse warning
uml: fix compile for x86-64
MPILIB: Add a missing ENOMEM check
tpm: fix (ACPI S3) suspend regression
nvme: fix merge error due to change of 'make_request_fn' fn type
xen: using EXPORT_SYMBOL requires including export.h
gpio: tps65910: Use correct offset for gpio initialization
acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec
intel_idle: Split up and provide per CPU initialization func
ACPI processor: Remove unneeded variable passed by acpi_processor_hotadd_init V2
tg3: Fix single-vector MSI-X code
openvswitch: Fix multipart datapath dumps.
ipv6: fix per device IP snmp counters
...
percpu_xxx funcs are duplicated with this_cpu_xxx funcs, so replace them
for further code clean up.
I don't know much of xen code. But, since the code is in x86 architecture,
the percpu_xxx is exactly same as this_cpu_xxx serials functions. So, the
change is safe.
Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Christoph Lameter <cl@gentwo.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If NR_CPUS < 256 then arch_spinlock_t is only 16 bits wide but struct
xen_spinlock is 32 bits. When a spin lock is contended and
xl->spinners is modified the two bytes immediately after the spin lock
would be corrupted.
This is a regression caused by 84eb950db1
(x86, ticketlock: Clean up types and accessors) which reduced the size
of arch_spinlock_t.
Fix this by making xl->spinners a u8 if NR_CPUS < 256. A
BUILD_BUG_ON() is also added to check the sizes of the two structures
are compatible.
In many cases this was not noticable as there would often be padding
bytes after the lock (e.g., if any of CONFIG_GENERIC_LOCKBREAK,
CONFIG_DEBUG_SPINLOCK, or CONFIG_DEBUG_LOCK_ALLOC were enabled).
The bnx2 driver is affected. In struct bnx2, phy_lock and
indirect_lock may have no padding after them. Contention on phy_lock
would corrupt indirect_lock making it appear locked and the driver
would deadlock.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
CC: stable@kernel.org #only 3.2
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/for-linus-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (37 commits)
xen/pciback: Expand the warning message to include domain id.
xen/pciback: Fix "device has been assigned to X domain!" warning
xen/pciback: Move the PCI_DEV_FLAGS_ASSIGNED ops to the "[un|]bind"
xen/xenbus: don't reimplement kvasprintf via a fixed size buffer
xenbus: maximum buffer size is XENSTORE_PAYLOAD_MAX
xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX.
Xen: consolidate and simplify struct xenbus_driver instantiation
xen-gntalloc: introduce missing kfree
xen/xenbus: Fix compile error - missing header for xen_initial_domain()
xen/netback: Enable netback on HVM guests
xen/grant-table: Support mappings required by blkback
xenbus: Use grant-table wrapper functions
xenbus: Support HVM backends
xen/xenbus-frontend: Fix compile error with randconfig
xen/xenbus-frontend: Make error message more clear
xen/privcmd: Remove unused support for arch specific privcmp mmap
xen: Add xenbus_backend device
xen: Add xenbus device driver
xen: Add privcmd device driver
xen/gntalloc: fix reference counts on multi-page mappings
...
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits)
reiserfs: Properly display mount options in /proc/mounts
vfs: prevent remount read-only if pending removes
vfs: count unlinked inodes
vfs: protect remounting superblock read-only
vfs: keep list of mounts for each superblock
vfs: switch ->show_options() to struct dentry *
vfs: switch ->show_path() to struct dentry *
vfs: switch ->show_devname() to struct dentry *
vfs: switch ->show_stats to struct dentry *
switch security_path_chmod() to struct path *
vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
vfs: trim includes a bit
switch mnt_namespace ->root to struct mount
vfs: take /proc/*/mounts and friends to fs/proc_namespace.c
vfs: opencode mntget() mnt_set_mountpoint()
vfs: spread struct mount - remaining argument of next_mnt()
vfs: move fsnotify junk to struct mount
vfs: move mnt_devname
vfs: move mnt_list to struct mount
vfs: switch pnode.h macros to struct mount *
...
* commit 'v3.2-rc3': (412 commits)
Linux 3.2-rc3
virtio-pci: make reset operation safer
virtio-mmio: Correct the name of the guest features selector
virtio: add HAS_IOMEM dependency to MMIO platform bus driver
eCryptfs: Extend array bounds for all filename chars
eCryptfs: Flush file in vma close
eCryptfs: Prevent file create race condition
regulator: TPS65910: Fix VDD1/2 voltage selector count
i2c: Make i2cdev_notifier_call static
i2c: Delete ANY_I2C_BUS
i2c: Fix device name for 10-bit slave address
i2c-algo-bit: Generate correct i2c address sequence for 10-bit target
drm: integer overflow in drm_mode_dirtyfb_ioctl()
Revert "of/irq: of_irq_find_parent: check for parent equal to child"
drivers/gpu/vga/vgaarb.c: add missing kfree
drm/radeon/kms/atom: unify i2c gpio table handling
drm/radeon/kms: fix up gpio i2c mask bits for r4xx for real
ttm: Don't return the bo reserved on error path
mount_subtree() pointless use-after-free
iio: fix a leak due to improper use of anon_inode_getfd()
...
* 'stable/for-linus-fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/swiotlb: Use page alignment for early buffer allocation.
xen: only limit memory map to maximum reservation for domain 0.
d312ae878b "xen: use maximum reservation to limit amount of usable RAM"
clamped the total amount of RAM to the current maximum reservation. This is
correct for dom0 but is not correct for guest domains. In order to boot a guest
"pre-ballooned" (e.g. with memory=1G but maxmem=2G) in order to allow for
future memory expansion the guest must derive max_pfn from the e820 provided by
the toolstack and not the current maximum reservation (which can reflect only
the current maximum, not the guest lifetime max). The existing algorithm
already behaves this correctly if we do not artificially limit the maximum
number of pages for the guest case.
For a guest booted with maxmem=512, memory=128 this results in:
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] Xen: 0000000000000000 - 00000000000a0000 (usable)
[ 0.000000] Xen: 00000000000a0000 - 0000000000100000 (reserved)
-[ 0.000000] Xen: 0000000000100000 - 0000000008100000 (usable)
-[ 0.000000] Xen: 0000000008100000 - 0000000020800000 (unusable)
+[ 0.000000] Xen: 0000000000100000 - 0000000020800000 (usable)
...
[ 0.000000] NX (Execute Disable) protection: active
[ 0.000000] DMI not present or invalid.
[ 0.000000] e820 update range: 0000000000000000 - 0000000000010000 (usable) ==> (reserved)
[ 0.000000] e820 remove range: 00000000000a0000 - 0000000000100000 (usable)
-[ 0.000000] last_pfn = 0x8100 max_arch_pfn = 0x1000000
+[ 0.000000] last_pfn = 0x20800 max_arch_pfn = 0x1000000
[ 0.000000] initial memory mapped : 0 - 027ff000
[ 0.000000] Base memory trampoline at [c009f000] 9f000 size 4096
-[ 0.000000] init_memory_mapping: 0000000000000000-0000000008100000
-[ 0.000000] 0000000000 - 0008100000 page 4k
-[ 0.000000] kernel direct mapping tables up to 8100000 @ 27bb000-27ff000
+[ 0.000000] init_memory_mapping: 0000000000000000-0000000020800000
+[ 0.000000] 0000000000 - 0020800000 page 4k
+[ 0.000000] kernel direct mapping tables up to 20800000 @ 26f8000-27ff000
[ 0.000000] xen: setting RW the range 27e8000 - 27ff000
[ 0.000000] 0MB HIGHMEM available.
-[ 0.000000] 129MB LOWMEM available.
-[ 0.000000] mapped low ram: 0 - 08100000
-[ 0.000000] low ram: 0 - 08100000
+[ 0.000000] 520MB LOWMEM available.
+[ 0.000000] mapped low ram: 0 - 20800000
+[ 0.000000] low ram: 0 - 20800000
With this change "xl mem-set <domain> 512M" will successfully increase the
guest RAM (by reducing the balloon).
There is no change for dom0.
Reported-and-Tested-by: George Shuklin <george.shuklin@gmail.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: stable@kernel.org
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
memblock_init() initializes arrays for regions and memblock itself;
however, all these can be done with struct initializers and
memblock_init() can be removed. This patch kills memblock_init() and
initializes memblock with struct initializer.
The only difference is that the first dummy entries don't have .nid
set to MAX_NUMNODES initially. This doesn't cause any behavior
difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "H. Peter Anvin" <hpa@zytor.com>
The idea behind commit d91ee5863b ("cpuidle: replace xen access to x86
pm_idle and default_idle") was to have one call - disable_cpuidle()
which would make pm_idle not be molested by other code. It disallows
cpuidle_idle_call to be set to pm_idle (which is excellent).
But in the select_idle_routine() and idle_setup(), the pm_idle can still
be set to either: amd_e400_idle, mwait_idle or default_idle. This
depends on some CPU flags (MWAIT) and in AMD case on the type of CPU.
In case of mwait_idle we can hit some instances where the hypervisor
(Amazon EC2 specifically) sets the MWAIT and we get:
Brought up 2 CPUs
invalid opcode: 0000 [#1] SMP
Pid: 0, comm: swapper Not tainted 3.1.0-0.rc6.git0.3.fc16.x86_64 #1
RIP: e030:[<ffffffff81015d1d>] [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
...
Call Trace:
[<ffffffff8100e2ed>] cpu_idle+0xae/0xe8
[<ffffffff8149ee78>] cpu_bringup_and_idle+0xe/0x10
RIP [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
RSP <ffff8801d28ddf10>
In the case of amd_e400_idle we don't get so spectacular crashes, but we
do end up making an MSR which is trapped in the hypervisor, and then
follow it up with a yield hypercall. Meaning we end up going to
hypervisor twice instead of just once.
The previous behavior before v3.0 was that pm_idle was set to
default_idle regardless of select_idle_routine/idle_setup.
We want to do that, but only for one specific case: Xen. This patch
does that.
Fixes RH BZ #739499 and Ubuntu #881076
Reported-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts & resolutions:
* arch/x86/xen/setup.c
dc91c728fd "xen: allow extra memory to be in multiple regions"
24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..."
conflicted on xen_add_extra_mem() updates. The resolution is
trivial as the latter just want to replace
memblock_x86_reserve_range() with memblock_reserve().
* drivers/pci/intel-iommu.c
166e9278a3 "x86/ia64: intel-iommu: move to drivers/iommu/"
5dfe8660a3 "bootmem: Replace work_with_active_regions() with..."
conflicted as the former moved the file under drivers/iommu/.
Resolved by applying the chnages from the latter on the moved
file.
* mm/Kconfig
6661672053 "memblock: add NO_BOOTMEM config symbol"
c378ddd53f "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option"
conflicted trivially. Both added config options. Just
letting both add their own options resolves the conflict.
* mm/memblock.c
d1f0ece6cd "mm/memblock.c: small function definition fixes"
ed7b56a799 "memblock: Remove memblock_memory_can_coalesce()"
confliected. The former updates function removed by the
latter. Resolution is trivial.
Signed-off-by: Tejun Heo <tj@kernel.org>
Receiver-side copying of packets is based on this implementation, it gives
better performance and better CPU accounting. It totally supports three types:
full-page, sub-page and transitive grants.
However this patch does not cover sub-page and transitive grants, it mainly
focus on Full-page part and implements grant table V2 interfaces corresponding
to what already exists in grant table V1, such as: grant table V2
initialization, mapping, releasing and exported interfaces.
Each guest can only supports one type of grant table type, every entry in grant
table should be the same version. It is necessary to set V1 or V2 version before
initializing the grant table.
Grant table exported interfaces of V2 are same with those of V1, Xen is
responsible to judge what grant table version guests are using in every grant
operation.
V2 fulfills the same role of V1, and it is totally backwards compitable with V1.
If dom0 support grant table V2, the guests runing on it can run with either V1
or V2.
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Annie Li <annie.li@oracle.com>
[v1: Modified alloc_vm_area call (new parameters), indentation, and cleanpatch
warnings]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This patch introduces new structures of grant table V2, grant table V2 is an
extension from V1. Grant table is shared between guest and Xen, and Xen is
responsible to do corresponding work for grant operations, such as: figure
out guest's grant table version, perform different actions based on
different grant table version, etc. Although full-page structure of V2
is different from V1, it play the same role as V1.
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Annie Li <annie.li@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Which is that 128GB is not going to happen with 32-bit PV DomU.
Lets use something more realistic. Also update the 64-bit to 500GB
which is the max a PV guest can do.
Signed-off-by: Maxim Uvarov <maxim.uvarov@oracle.com>
[v1: Updated 128GB->500GB for 64-bit]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
PVHVM running with more than 32 vcpus and pv_irq/pv_time enabled
need VCPU placement to work, or else it will softlockup.
CC: stable@kernel.org
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When mapping a foreign page with xenbus_map_ring_valloc() with the
GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and
pass a pointer to the PTE (in init_mm).
After the page is mapped, the usual fault mechanism can be used to
update additional MMs. This allows the vmalloc_sync_all() to be
removed from alloc_vm_area().
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
[v1: Squashed fix by Michal for no-mmu case]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
* 'upstream/xen-settime' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen/dom0: set wallclock time in Xen
xen: add dom0_op hypercall
xen/acpi: Domain0 acpi parser related platform hypercall
* 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
net: xen-netback: use API provided by xenbus module to map rings
block: xen-blkback: use API provided by xenbus module to map rings
xen: use generic functions instead of xen_{alloc, free}_vm_area()
* 'stable/drivers-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xenbus: don't rely on xen_initial_domain to detect local xenstore
xenbus: Fix loopback event channel assuming domain 0
xen/pv-on-hvm:kexec: Fix implicit declaration of function 'xen_hvm_domain'
xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel
xen/pv-on-hvm kexec: update xs_wire.h:xsd_sockmsg_type from xen-unstable
xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernel
xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports
xen/pv-on-hvm kexec: prevent crash in xenwatch_thread() when stale watch events arrive
* 'stable/drivers.bugfixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pciback: Check if the device is found instead of blindly assuming so.
xen/pciback: Do not dereference psdev during printk when it is NULL.
xen: remove XEN_PLATFORM_PCI config option
xen: XEN_PVHVM depends on PCI
xen/pciback: double lock typo
xen/pciback: use mutex rather than spinlock in vpci backend
xen/pciback: Use mutexes when working with Xenbus state transitions.
xen/pciback: miscellaneous adjustments
xen/pciback: use mutex rather than spinlock in passthrough backend
xen/pciback: use resource_size()
* 'stable/pci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pci: support multi-segment systems
xen-swiotlb: When doing coherent alloc/dealloc check before swizzling the MFNs.
xen/pci: make bus notifier handler return sane values
xen-swiotlb: fix printk and panic args
xen-swiotlb: Fix wrong panic.
xen-swiotlb: Retry up three times to allocate Xen-SWIOTLB
xen-pcifront: Update warning comment to use 'e820_host' option.
* 'stable/bug.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m/debugfs: Make type_name more obvious.
xen/p2m/debugfs: Fix potential pointer exception.
xen/enlighten: Fix compile warnings and set cx to known value.
xen/xenbus: Remove the unnecessary check.
xen/irq: If we fail during msi_capability_init return proper error code.
xen/events: Don't check the info for NULL as it is already done.
xen/events: BUG() when we can't allocate our event->irq array.
* 'stable/mmu.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: Fix selfballooning and ensure it doesn't go too far
xen/gntdev: Fix sleep-inside-spinlock
xen: modify kernel mappings corresponding to granted pages
xen: add an "highmem" parameter to alloc_xenballooned_pages
xen/p2m: Use SetPagePrivate and its friends for M2P overrides.
xen/p2m: Make debug/xen/mmu/p2m visible again.
Revert "xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set."
Per Ian Campbell suggestion to defend against future breakage
in case we expand the P2M values, incorporate the defines
in the string array.
Suggested-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We could be referencing the last + 1 element of level_name[]
array which would cause a pointer exception, because of the
initial setup of lvl=4.
[v1: No need to do this for type_name, pointed out by Ian Campbell]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We get:
linux/arch/x86/xen/enlighten.c: In function ‘xen_start_kernel’:
linux/arch/x86/xen/enlighten.c:226: warning: ‘cx’ may be used uninitialized in this function
linux/arch/x86/xen/enlighten.c:240: note: ‘cx’ was declared here
and the cx is really not set but passed in the xen_cpuid instruction
which masks the value with returned masked_ecx from cpuid. This
can potentially lead to invalid data being stored in cx.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Replace calls to the Xen-specific xen_alloc_vm_area() and
xen_free_vm_area() functions with the generic equivalent
(alloc_vm_area() and free_vm_area()).
On x86, these were identical already.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In xen_memory_setup() all reserved regions and gaps are set to an
identity (1-1) p2m mapping. If an available page has a PFN within one
of these 1-1 mappings it will become inaccessible (as it MFN is lost)
so release them before setting up the mapping.
This can make an additional 256 MiB or more of RAM available
(depending on the size of the reserved regions in the memory map) if
the initial pages overlap with reserved regions.
The 1:1 p2m mappings are also extended to cover partial pages. This
fixes an issue with (for example) systems with a BIOS that puts the
DMI tables in a reserved region that begins on a non-page boundary.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Allow the extra memory (used by the balloon driver) to be in multiple
regions (typically two regions, one for low memory and one for high
memory). This allows the balloon driver to increase the number of
available low pages (if the initial number if pages is small).
As a side effect, the algorithm for building the e820 memory map is
simpler and more obviously correct as the map supplied by the
hypervisor is (almost) used as is (in particular, all reserved regions
and gaps are preserved). Only RAM regions are altered and RAM regions
above max_pfn + extra_pages are marked as unused (the region is split
in two if necessary).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Allow the xen balloon driver to populate its list of extra pages from
more than one region of memory. This will allow platforms to provide
(for example) a region of low memory and a region of high memory.
The maximum possible number of extra regions is 128 (== E820MAX) which
is quite large so xen_extra_mem is placed in __initdata. This is safe
as both xen_memory_setup() and balloon_init() are in __init.
The balloon regions themselves are not altered (i.e., there is still
only the one region).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In xen_memory_setup() pages that occur in gaps in the memory map are
released back to Xen. This reduces the domain's current page count in
the hypervisor. The Xen balloon driver does not correctly decrease
its initial current_pages count to reflect this. If 'delta' pages are
released and the target is adjusted the resulting reservation is
always 'delta' less than the requested target.
This affects dom0 if the initial allocation of pages overlaps the PCI
memory region but won't affect most domU guests that have been setup
with pseudo-physical memory maps that don't have gaps.
Fix this by accouting for the released pages when starting the balloon
driver.
If the domain's targets are managed by xapi, the domain may eventually
run out of memory and die because xapi currently gets its target
calculations wrong and whenever it is restarted it always reduces the
target by 'delta'.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Xen PV on HVM guests require PCI support because they need the
xen-platform-pci driver in order to initialize xenbus.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If we want to use granted pages for AIO, changing the mappings of a user
vma and the corresponding p2m is not enough, we also need to update the
kernel mappings accordingly.
Currently this is only needed for pages that are created for user usages
through /dev/xen/gntdev. As in, pages that have been in use by the
kernel and use the P2M will not need this special mapping.
However there are no guarantees that in the future the kernel won't
start accessing pages through the 1:1 even for internal usage.
In order to avoid the complexity of dealing with highmem, we allocated
the pages lowmem.
We issue a HYPERVISOR_grant_table_op right away in
m2p_add_override and we remove the mappings using another
HYPERVISOR_grant_table_op in m2p_remove_override.
Considering that m2p_add_override and m2p_remove_override are called
once per page we use multicalls and hypercall batching.
Use the kmap_op pointer directly as argument to do the mapping as it is
guaranteed to be present up until the unmapping is done.
Before issuing any unmapping multicalls, we need to make sure that the
mapping has already being done, because we need the kmap->handle to be
set correctly.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v1: Removed GRANT_FRAME_BIT usage]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Linus Torvalds