Xiao Guangrong [Wed, 24 Feb 2016 09:51:12 +0000 (17:51 +0800)]
KVM: MMU: clear write-flooding on the fast path of tracked page
If the page fault is caused by write access on write tracked page, the
real shadow page walking is skipped, we lost the chance to clear write
flooding for the page structure current vcpu is using
Fix it by locklessly waking shadow page table to clear write flooding
on the shadow page structure out of mmu-lock. So that we change the
count to atomic_t
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Xiao Guangrong [Wed, 24 Feb 2016 09:51:11 +0000 (17:51 +0800)]
KVM: MMU: let page fault handler be aware tracked page
The page fault caused by write access on the write tracked page can not
be fixed, it always need to be emulated. page_fault_handle_page_track()
is the fast path we introduce here to skip holding mmu-lock and shadow
page table walking
However, if the page table is not present, it is worth making the page
table entry present and readonly to make the read access happy
mmu_need_write_protect() need to be cooked to avoid page becoming writable
when making page table present or sync/prefetch shadow page table entries
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These two functions are the user APIs:
- kvm_slot_page_track_add_page(): add the page to the tracking pool
after that later specified access on that page will be tracked
- kvm_slot_page_track_remove_page(): remove the page from the tracking
pool, the specified access on the page is not tracked after the last
user is gone
Both of these are called under the protection both of mmu-lock and
kvm->srcu or kvm->slots_lock
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Xiao Guangrong [Wed, 24 Feb 2016 09:51:09 +0000 (17:51 +0800)]
KVM: page track: add the framework of guest page tracking
The array, gfn_track[mode][gfn], is introduced in memory slot for every
guest page, this is the tracking count for the gust page on different
modes. If the page is tracked then the count is increased, the page is
not tracked after the count reaches zero
We use 'unsigned short' as the tracking count which should be enough as
shadow page table only can use 2^14 (2^3 for level, 2^1 for cr4_pae, 2^2
for quadrant, 2^3 for access, 2^1 for nxe, 2^1 for cr0_wp, 2^1 for
smep_andnot_wp, 2^1 for smap_andnot_wp, and 2^1 for smm) at most, there
is enough room for other trackers
Two callbacks, kvm_page_track_create_memslot() and
kvm_page_track_free_memslot() are implemented in this patch, they are
internally used to initialize and reclaim the memory of the array
Currently, only write track mode is supported
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Abstract the common operations from account_shadowed() and
unaccount_shadowed(), then introduce kvm_mmu_gfn_disallow_lpage()
and kvm_mmu_gfn_allow_lpage()
These two functions will be used by page tracking in the later patch
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Xiao Guangrong [Wed, 24 Feb 2016 09:51:06 +0000 (17:51 +0800)]
KVM: MMU: rename has_wrprotected_page to mmu_gfn_lpage_is_disallowed
kvm_lpage_info->write_count is used to detect if the large page mapping
for the gfn on the specified level is allowed, rename it to disallow_lpage
to reflect its purpose, also we rename has_wrprotected_page() to
mmu_gfn_lpage_is_disallowed() to make the code more clearer
Later we will extend this mechanism for page tracking: if the gfn is
tracked then large mapping for that gfn on any level is not allowed.
The new name is more straightforward
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Joerg Roedel [Mon, 29 Feb 2016 15:04:43 +0000 (16:04 +0100)]
kvm: x86: Convert ioapic->rtc_status.dest_map to a struct
Currently this is a bitmap which tracks which CPUs we expect
an EOI from. Move this bitmap to a struct so that we can
track additional information there.
Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Thu, 3 Mar 2016 13:35:44 +0000 (14:35 +0100)]
Merge branch 'kvm-ppc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD
The highlights are:
* Enable VFIO device on PowerPC, from David Gibson
* Optimizations to speed up IPIs between vcpus in HV KVM,
from Suresh Warrier (who is also Suresh E. Warrier)
* In-kernel handling of IOMMU hypercalls, and support for dynamic DMA
windows (DDW), from Alexey Kardashevskiy.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The existing KVM_CREATE_SPAPR_TCE only supports 32bit windows which is not
enough for directly mapped windows as the guest can get more than 4GB.
This adds KVM_CREATE_SPAPR_TCE_64 ioctl and advertises it
via KVM_CAP_SPAPR_TCE_64 capability. The table size is checked against
the locked memory limit.
Since 64bit windows are to support Dynamic DMA windows (DDW), let's add
@bus_offset and @page_shift which are also required by DDW.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@samba.org>
KVM: PPC: Add @page_shift to kvmppc_spapr_tce_table
At the moment the kvmppc_spapr_tce_table struct can only describe
4GB windows and handle fixed size (4K) pages. Dynamic DMA windows
support more so these limits need to be extended.
This replaces window_size (in bytes, 4GB max) with page_shift (32bit)
and size (64bit, in pages).
This should cause no behavioural change as this is changing
the internal structures only - the user interface still only
allows one to create a 32-bit table with 4KiB pages at this stage.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
KVM: PPC: Book3S HV: Add tunable to control H_IPI redirection
Redirecting the wakeup of a VCPU from the H_IPI hypercall to
a core running in the host is usually a good idea, most workloads
seemed to benefit. However, in one heavily interrupt-driven SMT1
workload, some regression was observed. This patch adds a kvm_hv
module parameter called h_ipi_redirect to control this feature.
The default value for this tunable is 1 - that is enable the feature.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
KVM: PPC: Book3S HV: Send IPI to host core to wake VCPU
This patch adds support to real-mode KVM to search for a core
running in the host partition and send it an IPI message with
VCPU to be woken. This avoids having to switch to the host
partition to complete an H_IPI hypercall when the VCPU which
is the target of the the H_IPI is not loaded (is not running
in the guest).
The patch also includes the support in the IPI handler running
in the host to do the wakeup by calling kvmppc_xics_ipi_action
for the PPC_MSG_RM_HOST_ACTION message.
When a guest is being destroyed, we need to ensure that there
are no pending IPIs waiting to wake up a VCPU before we free
the VCPUs of the guest. This is accomplished by:
- Forces a PPC_MSG_CALL_FUNCTION IPI to be completed by all CPUs
before freeing any VCPUs in kvm_arch_destroy_vm().
- Any PPC_MSG_RM_HOST_ACTION messages must be executed first
before any other PPC_MSG_CALL_FUNCTION messages.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Suresh Warrier [Thu, 17 Dec 2015 20:59:09 +0000 (14:59 -0600)]
KVM: PPC: Book3S HV: Host side kick VCPU when poked by real-mode KVM
This patch adds the support for the kick VCPU operation for
kvmppc_host_rm_ops. The kvmppc_xics_ipi_action() function
provides the function to be invoked for a host side operation
when poked by the real mode KVM. This is initiated by KVM by
sending an IPI to any free host core.
KVM real mode must set the rm_action to XICS_RM_KICK_VCPU and
rm_data to point to the VCPU to be woken up before sending the IPI.
Note that we have allocated one kvmppc_host_rm_core structure
per core. The above values need to be set in the structure
corresponding to the core to which the IPI will be sent.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
The kvmppc_host_rm_ops structure keeps track of which cores are
are in the host by maintaining a bitmask of active/runnable
online CPUs that have not entered the guest. This patch adds
support to manage the bitmask when a CPU is offlined or onlined
in the host.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Suresh Warrier [Thu, 17 Dec 2015 20:59:06 +0000 (14:59 -0600)]
KVM: PPC: Book3S HV: Host-side RM data structures
This patch defines the data structures to support the setting up
of host side operations while running in real mode in the guest,
and also the functions to allocate and free it.
The operations are for now limited to virtual XICS operations.
Currently, we have only defined one operation in the data
structure:
- Wake up a VCPU sleeping in the host when it
receives a virtual interrupt
The operations are assigned at the core level because PowerKVM
requires that the host run in SMT off mode. For each core,
we will need to manage its state atomically - where the state
is defined by:
1. Is the core running in the host?
2. Is there a Real Mode (RM) operation pending on the host?
Currently, core state is only managed at the whole-core level
even when the system is in split-core mode. This just limits
the number of free or "available" cores in the host to perform
any host-side operations.
The kvmppc_host_rm_core.rm_data allows any data to be passed by
KVM in real mode to the host core along with the operation to
be performed.
The kvmppc_host_rm_ops structure is allocated the very first time
a guest VM is started. Initial core state is also set - all online
cores are in the host. This structure is never deleted, not even
when there are no active guests. However, it needs to be freed
when the module is unloaded because the kvmppc_host_rm_ops_hv
can contain function pointers to kvm-hv.ko functions for the
different supported host operations.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Suresh Warrier [Thu, 17 Dec 2015 20:59:05 +0000 (14:59 -0600)]
powerpc/xics: Add icp_native_cause_ipi_rm
Function to cause an IPI by directly updating the MFFR register
in the XICS. The function is meant for real-mode callers since
they cannot use the smp_ops->cause_ipi function which uses an
ioremapped address.
Normal usage is for the the KVM real mode code to set the IPI message
using smp_muxed_ipi_message_pass and then invoke icp_native_cause_ipi_rm
to cause the actual IPI.
The function requires kvm_hstate.xics_phys to have been initialized
with the physical address of XICS.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Suresh Warrier [Thu, 17 Dec 2015 20:59:04 +0000 (14:59 -0600)]
powerpc/smp: Add smp_muxed_ipi_set_message
smp_muxed_ipi_message_pass() invokes smp_ops->cause_ipi, which
uses an ioremapped address to access registers on the XICS
interrupt controller to cause the IPI. Because of this real
mode callers cannot call smp_muxed_ipi_message_pass() for IPI
messaging.
This patch creates a separate function smp_muxed_ipi_set_message
just to set the IPI message without the cause_ipi routine.
After calling this function to set the IPI message, real
mode callers must cause the IPI by writing to the XICS registers
directly.
As part of this, we also change smp_muxed_ipi_message_pass
to call smp_muxed_ipi_set_message to set the message instead
of doing it directly inside the routine.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Suresh Warrier [Thu, 17 Dec 2015 20:59:03 +0000 (14:59 -0600)]
powerpc/smp: Support more IPI messages
This patch increases the number of demuxed messages for a
controller with a single ipi to 8 for 64-bit systems.
This is required because we want to use the IPI mechanism
to send messages from a CPU running in KVM real mode in a
guest to a CPU in the host to take some action. Currently,
we only support 4 messages and all 4 are already taken.
Define a fifth message PPC_MSG_RM_HOST_ACTION for this
purpose.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Takuya Yoshikawa [Mon, 22 Feb 2016 08:23:41 +0000 (17:23 +0900)]
KVM: x86: MMU: Move handle_mmio_page_fault() call to kvm_mmu_page_fault()
Rather than placing a handle_mmio_page_fault() call in each
vcpu->arch.mmu.page_fault() handler, moving it up to
kvm_mmu_page_fault() makes the code better:
- avoids code duplication
- for kvm_arch_async_page_ready(), which is the other caller of
vcpu->arch.mmu.page_fault(), removes an extra error_code check
- avoids returning both RET_MMIO_PF_* values and raw integer values
from vcpu->arch.mmu.page_fault()
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Takuya Yoshikawa [Mon, 22 Feb 2016 08:23:40 +0000 (17:23 +0900)]
KVM: x86: MMU: Consolidate quickly_check_mmio_pf() and is_mmio_page_fault()
These two have only slight differences:
- whether 'addr' is of type u64 or of type gva_t
- whether they have 'direct' parameter or not
Concerning the former, quickly_check_mmio_pf()'s u64 is better because
'addr' needs to be able to have both a guest physical address and a
guest virtual address.
The latter is just a stylistic issue as we can always calculate the mode
from the 'vcpu' as is_mmio_page_fault() does. This patch keeps the
parameter to make the following patch cleaner.
In addition, the patch renames the function to mmio_info_in_cache() to
make it clear what it actually checks for.
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Andrey Smetanin [Thu, 11 Feb 2016 13:44:59 +0000 (16:44 +0300)]
kvm/x86: Pass return code of kvm_emulate_hypercall
Pass the return code from kvm_emulate_hypercall on to the caller,
in order to allow it to indicate to the userspace that
the hypercall has to be handled there.
Also adjust all the existing code paths to return 1 to make sure the
hypercall isn't passed to the userspace without setting kvm_run
appropriately.
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Joerg Roedel <joro@8bytes.org> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Andrey Smetanin [Thu, 11 Feb 2016 13:44:58 +0000 (16:44 +0300)]
drivers/hv: Move VMBus hypercall codes into Hyper-V UAPI header
VMBus hypercall codes inside Hyper-V UAPI header will
be used by QEMU to implement VMBus host devices support.
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Acked-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Joerg Roedel <joro@8bytes.org> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org
[Do not rename the constant at the same time as moving it, as that
would cause semantic conflicts with the Hyper-V tree. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Wed, 10 Feb 2016 16:50:23 +0000 (17:50 +0100)]
KVM: x86: fix missed hardware breakpoints
Sometimes when setting a breakpoint a process doesn't stop on it.
This is because the debug registers are not loaded correctly on
VCPU load.
The following simple reproducer from Oleg Nesterov tries using debug
registers in both the host and the guest, for example by running "./bp
0 1" on the host and "./bp 14 15" under QEMU.
Jan Kiszka [Tue, 9 Feb 2016 19:15:18 +0000 (20:15 +0100)]
KVM: VMX: Fix guest debugging while in L2
When we take a #DB or #BP vmexit while in guest mode, we first of all
need to check if there is ongoing guest debugging that might be
interested in the event. Currently, we unconditionally leave L2 and
inject the event into L1 if it is intercepting the exceptions. That
breaks things marvelously.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now halt_poll_ns can be change during runtime. The
grow and shrink factors can only be set during module load.
Lets fix several aspects of grow shrink:
- make grow/shrink changeable by root
- make all variables unsigned int
- read the variables once to prevent races
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Tue, 16 Feb 2016 17:48:14 +0000 (18:48 +0100)]
Merge tag 'kvm-s390-next-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: Fixes and features for kvm/next (4.6)
1. also provide the floating point registers via sync regs
2. Separate out intruction vs. data accesses
3. Fix program interrupts in some cases
4. Documentation fixes
5. dirty log improvements for huge guests
This adds real and virtual mode handlers for the H_PUT_TCE_INDIRECT and
H_STUFF_TCE hypercalls for user space emulated devices such as IBMVIO
devices or emulated PCI. These calls allow adding multiple entries
(up to 512) into the TCE table in one call which saves time on
transition between kernel and user space.
The current implementation of kvmppc_h_stuff_tce() allows it to be
executed in both real and virtual modes so there is one helper.
The kvmppc_rm_h_put_tce_indirect() needs to translate the guest address
to the host address and since the translation is different, there are
2 helpers - one for each mode.
This implements the KVM_CAP_PPC_MULTITCE capability. When present,
the kernel will try handling H_PUT_TCE_INDIRECT and H_STUFF_TCE if these
are enabled by the userspace via KVM_CAP_PPC_ENABLE_HCALL.
If they can not be handled by the kernel, they are passed on to
the user space. The user space still has to have an implementation
for these.
Both HV and PR-syle KVM are supported.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
KVM: PPC: Move reusable bits of H_PUT_TCE handler to helpers
Upcoming multi-tce support (H_PUT_TCE_INDIRECT/H_STUFF_TCE hypercalls)
will validate TCE (not to have unexpected bits) and IO address
(to be within the DMA window boundaries).
This introduces helpers to validate TCE and IO address. The helpers are
exported as they compile into vmlinux (to work in realmode) and will be
used later by KVM kernel module in virtual mode.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
KVM: PPC: Account TCE-containing pages in locked_vm
At the moment pages used for TCE tables (in addition to pages addressed
by TCEs) are not counted in locked_vm counter so a malicious userspace
tool can call ioctl(KVM_CREATE_SPAPR_TCE) as many times as
RLIMIT_NOFILE and lock a lot of memory.
This adds counting for pages used for TCE tables.
This counts the number of pages required for a table plus pages for
the kvmppc_spapr_tce_table struct (TCE table descriptor) itself.
This changes release_spapr_tce_table() to store @npages on stack to
avoid calling kvmppc_stt_npages() in the loop (tiny optimization,
probably).
This does not change the amount of used memory.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
At the moment only spapr_tce_tables updates are protected against races
but not lookups. This fixes missing protection by using RCU for the list.
As lookups also happen in real mode, this uses
list_for_each_entry_lockless() (which is expected not to access any
vmalloc'd memory).
This converts release_spapr_tce_table() to a RCU scheduled handler.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes vmalloc_to_phys() public as there will be another user
(KVM in-kernel VFIO acceleration) for it soon. As this new user
can be compiled as a module, this exports the symbol.
As a little optimization, this changes the helper to call
vmalloc_to_pfn() instead of vmalloc_to_page() as the size of the
struct page may not be power-of-two aligned which will make gcc use
multiply instructions instead of shifts.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
David Gibson [Mon, 1 Feb 2016 00:14:15 +0000 (11:14 +1100)]
vfio: Enable VFIO device for powerpc
ec53500f "kvm: Add VFIO device" added a special KVM pseudo-device which is
used to handle any necessary interactions between KVM and VFIO.
Currently that device is built on x86 and ARM, but not powerpc, although
powerpc does support both KVM and VFIO. This makes things awkward in
userspace
Currently qemu prints an alarming error message if you attempt to use VFIO
and it can't initialize the KVM VFIO device. We don't want to remove the
warning, because lack of the KVM VFIO device could mean coherency problems
on x86. On powerpc, however, the error is harmless but looks disturbing,
and a test based on host architecture in qemu would be ugly, and break if
we do need the KVM VFIO device for something important in future.
There's nothing preventing the KVM VFIO device from being built for
powerpc, so this patch turns it on. It won't actually do anything, since
we don't define any of the arch_*() hooks, but it will make qemu happy and
we can extend it in future if we need to.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
KVM: s390: bail out early on fatal signal in dirty logging
A KVM_GET_DIRTY_LOG ioctl might take a long time.
This can result in fatal signals seemingly being ignored.
Lets bail out during the dirty bit sync, if a fatal signal
is pending.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: do not take mmap_sem on dirty log query
Dirty log query can take a long time for huge guests.
Holding the mmap_sem for very long times can cause some unwanted
latencies.
Turns out that we do not need to hold the mmap semaphore.
We hold the slots_lock for gfn->hva translation and walk the page
tables with that address, so no need to look at the VMAs. KVM also
holds a reference to the mm, which should prevent other things
going away. During the walk we take the necessary ptl locks.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: remove old fragment of vector registers
Since commit 9977e886cbbc ("s390/kernel: lazy restore fpu registers"),
vregs in struct sie_page is unsed. We can safely remove the field and
the definition.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: instruction-fetching exceptions on SIE faults
On instruction-fetch exceptions, we have to forward the PSW by any
valid ilc and correctly use that ilc when injecting the irq. Injection
will already take care of rewinding the PSW if we injected a nullifying
program irq, so we don't need special handling prior to injection.
Until now, autodetection would have guessed an ilc of 0.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
On SIE faults, the ilc cannot be detected automatically, as the icptcode
is 0. The ilc indicated in the program irq will always be 0. Therefore we
have to manually specify the ilc in order to tell the guest which ilen was
used when forwarding the PSW.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: irq delivery should not rely on icptcode
Program irq injection during program irq intercepts is the last candidates
that injects nullifying irqs and relies on delivery to do the right thing.
As we should not rely on the icptcode during any delivery (because that
value will not be migrated), let's add a flag, telling prog IRQ delivery
to not rewind the PSW in case of nullifying prog IRQs.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: clean up prog irq injection on prog irq icpts
__extract_prog_irq() is used only once for getting the program check data
in one place. Let's combine it with an injection function to avoid a memset
and to prevent misuse on injection by simplifying the interface to only
have the VCPU as parameter.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Let's use our fresh new function read_guest_instr() to access
guest storage via the correct addressing schema.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
When an instruction is to be fetched, special handling applies to
secondary-space mode and access-register mode. The instruction is to be
fetched from primary space.
We can easily support this by selecting the right asce for translation.
Access registers will never be used during translation, so don't
include them in the interface. As we only want to read from the current
PSW address for now, let's also hide that detail.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We will need special handling when fetching instructions, so let's
introduce new guest access modes GACC_FETCH and GACC_STORE instead
of a write flag. An additional patch will then introduce GACC_IFETCH.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We have to migrate the program irq ilc and someday we will have to
specify the ilc without KVM trying to autodetect the value.
Let's reuse one of the spare fields in our program irq that should
always be set to 0 by user space. Because we also want to make use
of 0 ilcs ("not available"), we need a validity indicator.
If no valid ilc is given, we try to autodetect the ilc via the current
icptcode and icptstatus + parameter and store the valid ilc in the
irq structure.
This has a nice effect: QEMU's making use of KVM_S390_IRQ /
KVM_S390_SET_IRQ_STATE / KVM_S390_GET_IRQ_STATE for migration will
directly migrate the ilc without any changes.
Please note that we use bit 0 as validity and bit 1,2 for the ilc, so
by applying the ilc mask we directly get the ilen which is usually what
we work with.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We have some confusion about ilc vs. ilen in our current code. So let's
correctly use the term ilen when dealing with (ilc << 1).
Program irq injection didn't take care of the correct ilc in case of
irqs triggered by EXECUTE functions, let's provide one function
kvm_s390_get_ilen() to take care of all that.
Also, manually specifying in intercept handlers the size of the
instruction (and sometimes overwriting that value for EXECUTE internally)
doesn't make too much sense. So also provide the functions:
- kvm_s390_retry_instr to retry the currently intercepted instruction
- kvm_s390_rewind_psw to rewind the PSW without internal overwrites
- kvm_s390_forward_psw to forward the PSW
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
As we already store the floating point registers in the vector save area
in floating point register format when we don't have MACHINE_HAS_VX, we can
directly expose them to user space using a new sync flag.
The floating point registers will be valid when KVM_SYNC_FPRS is set. The
fpc will also be valid when KVM_SYNC_FPRS is set.
Either KVM_SYNC_FPRS or KVM_SYNC_VRS will be enabled, never both.
Let's also change two positions where we access vrs, making the code easier
to read and one comment superfluous.
Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
If we have MACHINE_HAS_VX, the floating point registers are stored
in the vector register format, event if the guest isn't enabled for vector
registers. So we can allow KVM_SYNC_VRS as soon as MACHINE_HAS_VX is
available.
This can in return be used by user space to support floating point
registers via struct kvm_run when the machine has vector registers.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Paolo Bonzini [Fri, 8 Jan 2016 12:48:51 +0000 (13:48 +0100)]
KVM: x86: consolidate different ways to test for in-kernel LAPIC
Different pieces of code checked for vcpu->arch.apic being (non-)NULL,
or used kvm_vcpu_has_lapic (more optimized) or lapic_in_kernel.
Replace everything with lapic_in_kernel's name and kvm_vcpu_has_lapic's
implementation.
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Feng Wu [Mon, 25 Jan 2016 08:53:34 +0000 (16:53 +0800)]
KVM: x86: Add lowest-priority support for vt-d posted-interrupts
Use vector-hashing to deliver lowest-priority interrupts for
VT-d posted-interrupts. This patch extends kvm_intr_is_single_vcpu()
to support lowest-priority handling.
Feng Wu [Mon, 25 Jan 2016 08:53:33 +0000 (16:53 +0800)]
KVM: x86: Use vector-hashing to deliver lowest-priority interrupts
Use vector-hashing to deliver lowest-priority interrupts, As an
example, modern Intel CPUs in server platform use this method to
handle lowest-priority interrupts.
Paolo Bonzini [Fri, 22 Jan 2016 10:39:22 +0000 (11:39 +0100)]
KVM: x86: introduce do_shl32_div32
This is similar to the existing div_frac function, but it returns the
remainder too. Unlike div_frac, it can be used to implement long
division, e.g. (a << 64) / b for 32-bit a and b.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linus Torvalds [Mon, 8 Feb 2016 18:32:30 +0000 (10:32 -0800)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"KVM-ARM fixes, mostly coming from the PMU work"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
arm64: KVM: Fix guest dead loop when register accessor returns false
arm64: KVM: Fix comments of the CP handler
arm64: KVM: Fix wrong use of the CPSR MODE mask for 32bit guests
arm64: KVM: Obey RES0/1 reserved bits when setting CPTR_EL2
arm64: KVM: Fix AArch64 guest userspace exception injection
Linus Torvalds [Mon, 8 Feb 2016 18:20:06 +0000 (10:20 -0800)]
Merge tag 'regmap-fix-v4.5-big-endian' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap fix from Mark Brown:
"A single revert back to v4.4 endianness handling.
Commit 29bb45f25ff3 ("regmap-mmio: Use native endianness for
read/write") attempted to fix some long standing bugs in the MMIO
implementation for big endian systems caused by duplicate byte
swapping in both regmap and readl()/writel(). Sadly the fix makes
things worse rather than better, so revert it for now"
* tag 'regmap-fix-v4.5-big-endian' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: mmio: Revert to v4.4 endianness handling
Paolo Bonzini [Mon, 8 Feb 2016 15:20:51 +0000 (16:20 +0100)]
Merge tag 'kvm-arm-for-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master
KVM/ARM fixes for v4.5-rc2
A few random fixes, mostly coming from the PMU work by Shannon:
- fix for injecting faults coming from the guest's userspace
- cleanup for our CPTR_EL2 accessors (reserved bits)
- fix for a bug impacting perf (user/kernel discrimination)
- fix for a 32bit sysreg handling bug
Linus Torvalds [Sun, 7 Feb 2016 23:23:20 +0000 (15:23 -0800)]
Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"The first real batch of fixes for this release cycle, so there are a
few more than usual.
Most of these are fixes and tweaks to board support (DT bugfixes,
etc). I've also picked up a couple of small cleanups that seemed
innocent enough that there was little reason to wait (const/
__initconst and Kconfig deps).
Quite a bit of the changes on OMAP were due to fixes to no longer
write to rodata from assembly when ARM_KERNMEM_PERMS was enabled, but
there were also other fixes.
Kirkwood had a bunch of gpio fixes for some boards. OMAP had RTC
fixes on OMAP5, and Nomadik had changes to MMC parameters in DT.
All in all, mostly the usual mix of various fixes"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (46 commits)
ARM: multi_v7_defconfig: enable DW_WATCHDOG
ARM: nomadik: fix up SD/MMC DT settings
ARM64: tegra: Add chosen node for tegra132 norrin
ARM: realview: use "depends on" instead of "if" after prompt
ARM: tango: use "depends on" instead of "if" after prompt
ARM: tango: use const and __initconst for smp_operations
ARM: realview: use const and __initconst for smp_operations
bus: uniphier-system-bus: revive tristate prompt
arm64: dts: Add missing DMA Abort interrupt to Juno
bus: vexpress-config: Add missing of_node_put
ARM: dts: am57xx: sbc-am57x: correct Eth PHY settings
ARM: dts: am57xx: cl-som-am57x: fix CPSW EMAC pinmux
ARM: dts: am57xx: sbc-am57x: fix UART3 pinmux
ARM: dts: am57xx: cl-som-am57x: update SPI Flash frequency
ARM: dts: am57xx: cl-som-am57x: set HOST mode for USB2
ARM: dts: am57xx: sbc-am57x: fix SB-SOM EEPROM I2C address
ARM: dts: LogicPD Torpedo: Revert Duplicative Entries
ARM: dts: am437x: pixcir_tangoc: use correct flags for irq types
ARM: dts: am4372: fix irq type for arm twd and global timer
ARM: dts: at91: sama5d4 xplained: fix phy0 IRQ type
...
Linus Torvalds [Sun, 7 Feb 2016 06:14:46 +0000 (22:14 -0800)]
Merge tag 'usb-4.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are some USB fixes for 4.5-rc3.
The usual, xhci fixes for reported issues, combined with some small
gadget driver fixes, and a MAINTAINERS file update. All have been in
linux-next with no reported issues"
* tag 'usb-4.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
xhci: harden xhci_find_next_ext_cap against device removal
xhci: Fix list corruption in urb dequeue at host removal
usb: host: xhci-plat: fix NULL pointer in probe for device tree case
usb: xhci-mtk: fix AHB bus hang up caused by roothubs polling
usb: xhci-mtk: fix bpkts value of LS/HS periodic eps not behind TT
usb: xhci: apply XHCI_PME_STUCK_QUIRK to Intel Broxton-M platforms
usb: xhci: set SSIC port unused only if xhci_suspend succeeds
usb: xhci: add a quirk bit for ssic port unused
usb: xhci: handle both SSIC ports in PME stuck quirk
usb: dwc3: gadget: set the OTG flag in dwc3 gadget driver.
Revert "xhci: don't finish a TD if we get a short-transfer event mid TD"
MAINTAINERS: fix my email address
usb: dwc2: Fix probe problem on bcm2835
Revert "usb: dwc2: Move reset into dwc2_get_hwparams()"
usb: musb: ux500: Fix NULL pointer dereference at system PM
usb: phy: mxs: declare variable with initialized value
usb: phy: msm: fix error handling in probe.
Linus Torvalds [Sun, 7 Feb 2016 06:13:16 +0000 (22:13 -0800)]
Merge tag 'staging-4.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO driver fixes from Greg KH:
"Here are some IIO and staging driver fixes for 4.5-rc3.
All of them, except one, are for IIO drivers, and one is for a speakup
driver fix caused by some earlier patches, to resolve a reported build
failure"
* tag 'staging-4.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
Staging: speakup: Fix allyesconfig build on mn10300
iio: dht11: Use boottime
iio: ade7753: avoid uninitialized data
iio: pressure: mpl115: fix temperature offset sign
iio: imu: Fix dependencies for !HAS_IOMEM archs
staging: iio: Fix dependencies for !HAS_IOMEM archs
iio: adc: Fix dependencies for !HAS_IOMEM archs
iio: inkern: fix a NULL dereference on error
iio:adc:ti_am335x_adc Fix buffered mode by identifying as software buffer.
iio: light: acpi-als: Report data as processed
iio: dac: mcp4725: set iio name property in sysfs
iio: add HAS_IOMEM dependency to VF610_ADC
iio: add IIO_TRIGGER dependency to STK8BA50
iio: proximity: lidar: correct return value
iio-light: Use a signed return type for ltr501_match_samp_freq()
Linus Torvalds [Sat, 6 Feb 2016 04:20:07 +0000 (20:20 -0800)]
Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
"22 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (22 commits)
epoll: restrict EPOLLEXCLUSIVE to POLLIN and POLLOUT
radix-tree: fix oops after radix_tree_iter_retry
MAINTAINERS: trim the file triggers for ABI/API
dax: dirty inode only if required
thp: make deferred_split_scan() work again
mm: replace vma_lock_anon_vma with anon_vma_lock_read/write
ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup
um: asm/page.h: remove the pte_high member from struct pte_t
mm, hugetlb: don't require CMA for runtime gigantic pages
mm/hugetlb: fix gigantic page initialization/allocation
mm: downgrade VM_BUG in isolate_lru_page() to warning
mempolicy: do not try to queue pages from !vma_migratable()
mm, vmstat: fix wrong WQ sleep when memory reclaim doesn't make any progress
vmstat: make vmstat_update deferrable
mm, vmstat: make quiet_vmstat lighter
mm/Kconfig: correct description of DEFERRED_STRUCT_PAGE_INIT
memblock: don't mark memblock_phys_mem_size() as __init
dump_stack: avoid potential deadlocks
mm: validate_mm browse_rb SMP race condition
m32r: fix build failure due to SMP and MMU
...
Linus Torvalds [Sat, 6 Feb 2016 03:52:57 +0000 (19:52 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph fixes from Sage Weil:
"We have a few wire protocol compatibility fixes, ports of a few recent
CRUSH mapping changes, and a couple error path fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: MOSDOpReply v7 encoding
libceph: advertise support for TUNABLES5
crush: decode and initialize chooseleaf_stable
crush: add chooseleaf_stable tunable
crush: ensure take bucket value is valid
crush: ensure bucket id is valid before indexing buckets array
ceph: fix snap context leak in error path
ceph: checking for IS_ERR instead of NULL
Linus Torvalds [Sat, 6 Feb 2016 03:38:15 +0000 (19:38 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Fixes all over the place:
- amdkfd: two static checker fixes
- mst: a bunch of static checker and spec/hw interaction fixes
- amdgpu: fix Iceland hw properly, and some fiji bugs, along with
some write-combining fixes.
- exynos: some regression fixes
- adv7511: fix some EDID reading issues"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (38 commits)
drm/dp/mst: deallocate payload on port destruction
drm/dp/mst: Reverse order of MST enable and clearing VC payload table.
drm/dp/mst: move GUID storage from mgr, port to only mst branch
drm/dp/mst: change MST detection scheme
drm/dp/mst: Calculate MST PBN with 31.32 fixed point
drm: Add drm_fixp_from_fraction and drm_fixp2int_ceil
drm/mst: Add range check for max_payloads during init
drm/mst: Don't ignore the MST PBN self-test result
drm: fix missing reference counting decrease
drm/amdgpu: disable uvd and vce clockgating on Fiji
drm/amdgpu: remove exp hardware support from iceland
drm/amdgpu: load MEC ucode manually on iceland
drm/amdgpu: don't load MEC2 on topaz
drm/amdgpu: drop topaz support from gmc8 module
drm/amdgpu: pull topaz gmc bits into gmc_v7
drm/amdgpu: The VI specific EXE bit should only apply to GMC v8.0 above
drm/amdgpu: iceland use CI based MC IP
drm/amdgpu: move gmc7 support out of CIK dependency
drm/amdgpu/gfx7: enable cp inst/reg error interrupts
drm/amdgpu/gfx8: enable cp inst/reg error interrupts
...
Linus Torvalds [Sat, 6 Feb 2016 02:11:23 +0000 (18:11 -0800)]
Merge tag 'pm+acpi-4.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI fixes from Rafael Wysocki:
"These are: a fix for a recently introduced false-positive warnings
about PM domain pointers being changed inappropriately (harmless but
annoying), an MCH size workaround quirk for one more platform, a
compiler warning fix (generic power domains framework), an ACPI LPSS
(Intel SoCs) driver fixup and a cleanup of the ACPI CPPC core code.
Specifics:
- PM core fix to avoid false-positive warnings generated when the
pm_domain field is cleared for a device that appears to be bound to
a driver (Rafael Wysocki).
- New MCH size workaround quirk for Intel Haswell-ULT (Josh Boyer).
- Fix for an "unused function" compiler warning in the generic power
domains framework (Ulf Hansson).
- Fixup for the ACPI driver for Intel SoCs (acpi-lpss) to set the PM
domain pointer of a device properly in one place that was
overlooked by a recent PM core update (Andy Shevchenko).
- Removal of a redundant function declaration in the ACPI CPPC core
code (Timur Tabi)"
* tag 'pm+acpi-4.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: Avoid false-positive warnings in dev_pm_domain_set()
PM / Domains: Silence compiler warning for an unused function
ACPI / CPPC: remove redundant mbox_send_message() declaration
ACPI / LPSS: set PM domain via helper setter
PNP: Add Haswell-ULT to Intel MCH size workaround
Jason Baron [Fri, 5 Feb 2016 23:37:04 +0000 (15:37 -0800)]
epoll: restrict EPOLLEXCLUSIVE to POLLIN and POLLOUT
In the current implementation of the EPOLLEXCLUSIVE flag (added for
4.5-rc1), if epoll waiters create different POLL* sets and register them
as exclusive against the same target fd, the current implementation will
stop waking any further waiters once it finds the first idle waiter.
This means that waiters could miss wakeups in certain cases.
For example, when we wake up a pipe for reading we do:
wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM); So if
one epoll set or epfd is added to pipe p with POLLIN and a second set
epfd2 is added to pipe p with POLLRDNORM, only epfd may receive the
wakeup since the current implementation will stop after it finds any
intersection of events with a waiter that is blocked in epoll_wait().
We could potentially address this by requiring all epoll waiters that
are added to p be required to pass the same set of POLL* events. IE the
first EPOLL_CTL_ADD that passes EPOLLEXCLUSIVE establishes the set POLL*
flags to be used by any other epfds that are added as EPOLLEXCLUSIVE.
However, I think it might be somewhat confusing interface as we would
have to reference count the number of users for that set, and so
userspace would have to keep track of that count, or we would need a
more involved interface. It also adds some shared state that we'd have
store somewhere. I don't think anybody will want to bloat
__wait_queue_head for this.
I think what we could do instead, is to simply restrict EPOLLEXCLUSIVE
such that it can only be specified with EPOLLIN and/or EPOLLOUT. So
that way if the wakeup includes 'POLLIN' and not 'POLLOUT', we can stop
once we hit the first idle waiter that specifies the EPOLLIN bit, since
any remaining waiters that only have 'POLLOUT' set wouldn't need to be
woken. Likewise, we can do the same thing if 'POLLOUT' is in the wakeup
bit set and not 'POLLIN'. If both 'POLLOUT' and 'POLLIN' are set in the
wake bit set (there is at least one example of this I saw in fs/pipe.c),
then we just wake the entire exclusive list. Having both 'POLLOUT' and
'POLLIN' both set should not be on any performance critical path, so I
think that's ok (in fs/pipe.c its in pipe_release()). We also continue
to include EPOLLERR and EPOLLHUP by default in any exclusive set. Thus,
the user can specify EPOLLERR and/or EPOLLHUP but is not required to do
so.
Since epoll waiters may be interested in other events as well besides
EPOLLIN, EPOLLOUT, EPOLLERR and EPOLLHUP, these can still be added by
doing a 'dup' call on the target fd and adding that as one normally
would with EPOLL_CTL_ADD. Since I think that the POLLIN and POLLOUT
events are what we are interest in balancing, I think that the 'dup'
thing could perhaps be added to only one of the waiter threads.
However, I think that EPOLLIN, EPOLLOUT, EPOLLERR and EPOLLHUP should be
sufficient for the majority of use-cases.
Since EPOLLEXCLUSIVE is intended to be used with a target fd shared
among multiple epfds, where between 1 and n of the epfds may receive an
event, it does not satisfy the semantics of EPOLLONESHOT where only 1
epfd would get an event. Thus, it is not allowed to be specified in
conjunction with EPOLLEXCLUSIVE.
EPOLL_CTL_MOD is also not allowed if the fd was previously added as
EPOLLEXCLUSIVE. It seems with the limited number of flags to not be as
interesting, but this could be relaxed at some further point.
Signed-off-by: Jason Baron <jbaron@akamai.com> Tested-by: Madars Vitolins <m@silodev.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Eric Wong <normalperson@yhbt.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Helper radix_tree_iter_retry() resets next_index to the current index.
In following radix_tree_next_slot current chunk size becomes zero. This
isn't checked and it tries to dereference null pointer in slot.
Tagged iterator is fine because retry happens only at slot 0 where tag
bitmask in iter->tags is filled with single bit.
Fixes: 46437f9a554f ("radix-tree: fix race in gang lookup") Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ohad Ben-Cohen <ohad@wizery.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit ea8f8fc8631 ("MAINTAINERS: add linux-api for review of API/ABI
changes") added file triggers for various paths that likely indicated
API/ABI changes. However, catching all changes in Documentation/ABI/
and include/uapi/ produces a large volume of mail to linux-api, rather
than only API/ABI changes. Drop those two entries, but leave
include/linux/syscalls.h and kernel/sys_ni.c to catch syscall-related
changes.
Dmitry Monakhov [Fri, 5 Feb 2016 23:36:55 +0000 (15:36 -0800)]
dax: dirty inode only if required
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to iterate over split_queue, not local empty list to get
anything split from the shrinker.
Fixes: e3ae19535c66 ("thp: limit number of object to scan on deferred_split_scan()") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: replace vma_lock_anon_vma with anon_vma_lock_read/write
Sequence vma_lock_anon_vma() - vma_unlock_anon_vma() isn't safe if
anon_vma appeared between lock and unlock. We have to check anon_vma
first or call anon_vma_prepare() to be sure that it's here. There are
only few users of these legacy helpers. Let's get rid of them.
This patch fixes anon_vma lock imbalance in validate_mm(). Write lock
isn't required here, read lock is enough.
And reorders expand_downwards/expand_upwards: security_mmap_addr() and
wrapping-around check don't have to be under anon vma lock.
Link: https://lkml.kernel.org/r/CACT4Y+Y908EjM2z=706dv4rV6dWtxTLK9nFg9_7DhRMLppBo2g@mail.gmail.com Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xuejiufei [Fri, 5 Feb 2016 23:36:47 +0000 (15:36 -0800)]
ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup
When recovery master down, dlm_do_local_recovery_cleanup() only remove
the $RECOVERY lock owned by dead node, but do not clear the refmap bit.
Which will make umount thread falling in dead loop migrating $RECOVERY
to the dead node.
Signed-off-by: xuejiufei <xuejiufei@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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