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>
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>
__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>
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>
Do for kvm_cpu_has_pending_timer and kvm_inject_pending_timer_irqs
what the other irq.c routines have been doing.
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Usually the in-kernel APIC's existence is checked in the caller. Do not
bother checking it again in lapic.c.
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add host irq information in trace event, so we can better understand
which irq is in posted mode.
Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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.
Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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.
Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the interrupt is not single destination any more, we need
to change back IRTE to remapped mode explicitly.
Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
Commit 29bb45f25f (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() which affected MIPS systems as when they are in big
endian mode they flip the endianness of all registers in the system, not
just the CPU. MIPS systems had worked around this by declaring regmap
using IPs as little endian which is inaccurate, unfortunately the issue
had not been reported.
Sadly the fix makes things worse rather than better. By changing the
behaviour to match the documentation it caused behaviour changes for
other IPs which broke them and by using the __raw I/O accessors to avoid
the endianness swapping in readl()/writel() it removed some memory
ordering guarantees and could potentially generate unvirtualisable
instructions on some architectures.
Unfortunately sorting out all this mess in any half way sensible fashion
was far too invasive to go in during an -rc cycle so instead let's go
back to the old broken behaviour for v4.5, the better fixes are already
queued for v4.6. This does mean that we keep the broken MIPS DTs for
another release but that seems the least bad way of handling the
situation.
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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 29bb45f25f ("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
Fix the doubled "started" and tidy up the following sentences.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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
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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
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.
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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
...
Pull mailbox fixes from Jassi Brar:
- fix getting element from the pcc-channels array by simply indexing
into it
- prevent building mailbox-test driver for archs that don't have IOMEM
* 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
mailbox: Fix dependencies for !HAS_IOMEM archs
mailbox: pcc: fix channel calculation in get_pcc_channel()
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.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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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.
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.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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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()
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
...
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
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
...
- 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).
/
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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
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: 46437f9a55 ("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 ea8f8fc863 ("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.
[josh@joshtriplett.org: redid changelog]
Signed-off-by: Michael Kerrisk <mtk.man-pages@gmail.com>
Acked-by: Shuah khan <shuahkh@osg.samsung.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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: e3ae19535c ("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>
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>
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>
Commit 16da306849 ("um: kill pfn_t") introduced a compile warning for
defconfig (SUBARCH=i386):
arch/um/kernel/skas/mmu.c:38:206:
warning: right shift count >= width of type [-Wshift-count-overflow]
Aforementioned patch changes the definition of the phys_to_pfn() macro
from
((pfn_t) ((p) >> PAGE_SHIFT))
to
((p) >> PAGE_SHIFT)
This effectively changes the phys_to_pfn() expansion's type from
unsigned long long to unsigned long.
Through the callchain init_stub_pte() => mk_pte(), the expansion of
phys_to_pfn() is (indirectly) fed into the 'phys' argument of the
pte_set_val(pte, phys, prot) macro, eventually leading to
(pte).pte_high = (phys) >> 32;
This results in the warning from above.
Since UML only deals with 32 bit addresses, the upper 32 bits from
'phys' used to be always zero anyway. Also, all page protection flags
defined by UML don't use any bits beyond bit 9. Since the contents of a
PTE are defined within architecture scope only, the ->pte_high member
can be safely removed.
Remove the ->pte_high member from struct pte_t.
Rename ->pte_low to ->pte.
Adapt the pte helper macros in arch/um/include/asm/page.h.
Noteworthy is the pte_copy() macro where a smp_wmb() gets dropped. This
write barrier doesn't seem to be paired with any read barrier though and
thus, was useless anyway.
Fixes: 16da306849 ("um: kill pfn_t")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 944d9fec8d ("hugetlb: add support for gigantic page allocation
at runtime") has added the runtime gigantic page allocation via
alloc_contig_range(), making this support available only when CONFIG_CMA
is enabled. Because it doesn't depend on MIGRATE_CMA pageblocks and the
associated infrastructure, it is possible with few simple adjustments to
require only CONFIG_MEMORY_ISOLATION instead of full CONFIG_CMA.
After this patch, alloc_contig_range() and related functions are
available and used for gigantic pages with just CONFIG_MEMORY_ISOLATION
enabled. Note CONFIG_CMA selects CONFIG_MEMORY_ISOLATION. This allows
supporting runtime gigantic pages without the CMA-specific checks in
page allocator fastpaths.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Attempting to preallocate 1G gigantic huge pages at boot time with
"hugepagesz=1G hugepages=1" on the kernel command line will prevent
booting with the following:
kernel BUG at mm/hugetlb.c:1218!
When mapcount accounting was reworked, the setting of
compound_mapcount_ptr in prep_compound_gigantic_page was overlooked. As
a result, the validation of mapcount in free_huge_page fails.
The "BUG_ON" checks in free_huge_page were also changed to
"VM_BUG_ON_PAGE" to assist with debugging.
Fixes: 53f9263bab ("mm: rework mapcount accounting to enable 4k mapping of THPs")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Calling isolate_lru_page() is wrong and shouldn't happen, but it not
nessesary fatal: the page just will not be isolated if it's not on LRU.
Let's downgrade the VM_BUG_ON_PAGE() to WARN_RATELIMIT().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Maybe I miss some point, but I don't see a reason why we try to queue
pages from non migratable VMAs.
This testcase steps on VM_BUG_ON_PAGE() in isolate_lru_page():
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/mman.h>
#include <numaif.h>
#define SIZE 0x2000
int foo;
int main()
{
int fd;
char *p;
unsigned long mask = 2;
fd = open("/dev/sg0", O_RDWR);
p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
/* Faultin pages */
foo = p[0] + p[0x1000];
mbind(p, SIZE, MPOL_BIND, &mask, 4, MPOL_MF_MOVE | MPOL_MF_STRICT);
return 0;
}
The only case when we can queue pages from such VMA is MPOL_MF_STRICT
plus MPOL_MF_MOVE or MPOL_MF_MOVE_ALL for VMA which has pages on LRU,
but gfp mask is not sutable for migaration (see mapping_gfp_mask() check
in vma_migratable()). That's looks like a bug to me.
Let's filter out non-migratable vma at start of queue_pages_test_walk()
and go to queue_pages_pte_range() only if MPOL_MF_MOVE or
MPOL_MF_MOVE_ALL flag is set.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Stancek has reported that system occasionally hanging after "oom01"
testcase from LTP triggers OOM. Guessing from a result that there is a
kworker thread doing memory allocation and the values between "Node 0
Normal free:" and "Node 0 Normal:" differs when hanging, vmstat is not
up-to-date for some reason.
According to commit 373ccbe592 ("mm, vmstat: allow WQ concurrency to
discover memory reclaim doesn't make any progress"), it meant to force
the kworker thread to take a short sleep, but it by error used
schedule_timeout(1). We missed that schedule_timeout() in state
TASK_RUNNING doesn't do anything.
Fix it by using schedule_timeout_uninterruptible(1) which forces the
kworker thread to take a short sleep in order to make sure that vmstat
is up-to-date.
Fixes: 373ccbe592 ("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Cristopher Lameter <clameter@sgi.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Arkadiusz Miskiewicz <arekm@maven.pl>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 0eb77e9880 ("vmstat: make vmstat_updater deferrable again and
shut down on idle") made vmstat_shepherd deferrable. vmstat_update
itself is still useing standard timer which might interrupt idle task.
This is possible because "mm, vmstat: make quiet_vmstat lighter" removed
cancel_delayed_work from the quiet_vmstat.
Change vmstat_work to use DEFERRABLE_WORK to prevent from pointless
wakeups from the idle context.
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike has reported a considerable overhead of refresh_cpu_vm_stats from
the idle entry during pipe test:
12.89% [kernel] [k] refresh_cpu_vm_stats.isra.12
4.75% [kernel] [k] __schedule
4.70% [kernel] [k] mutex_unlock
3.14% [kernel] [k] __switch_to
This is caused by commit 0eb77e9880 ("vmstat: make vmstat_updater
deferrable again and shut down on idle") which has placed quiet_vmstat
into cpu_idle_loop. The main reason here seems to be that the idle
entry has to get over all zones and perform atomic operations for each
vmstat entry even though there might be no per cpu diffs. This is a
pointless overhead for _each_ idle entry.
Make sure that quiet_vmstat is as light as possible.
First of all it doesn't make any sense to do any local sync if the
current cpu is already set in oncpu_stat_off because vmstat_update puts
itself there only if there is nothing to do.
Then we can check need_update which should be a cheap way to check for
potential per-cpu diffs and only then do refresh_cpu_vm_stats.
The original patch also did cancel_delayed_work which we are not doing
here. There are two reasons for that. Firstly cancel_delayed_work from
idle context will blow up on RT kernels (reported by Mike):
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.5.0-rt3 #7
Hardware name: MEDION MS-7848/MS-7848, BIOS M7848W08.20C 09/23/2013
Call Trace:
dump_stack+0x49/0x67
___might_sleep+0xf5/0x180
rt_spin_lock+0x20/0x50
try_to_grab_pending+0x69/0x240
cancel_delayed_work+0x26/0xe0
quiet_vmstat+0x75/0xa0
cpu_idle_loop+0x38/0x3e0
cpu_startup_entry+0x13/0x20
start_secondary+0x114/0x140
And secondly, even on !RT kernels it might add some non trivial overhead
which is not necessary. Even if the vmstat worker wakes up and preempts
idle then it will be most likely a single shot noop because the stats
were already synced and so it would end up on the oncpu_stat_off anyway.
We just need to teach both vmstat_shepherd and vmstat_update to stop
scheduling the worker if there is nothing to do.
[mgalbraith@suse.de: cancel pending work of the cpu_stat_off CPU]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The description mentions kswapd threads, while the deferred struct page
initialization is actually done by one-off "pgdatinitX" threads.
Fix the description so that potentially users are not confused about
pgdatinit threads using CPU after boot instead of kswapd.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At the moment memblock_phys_mem_size() is marked as __init, and so is
discarded after boot. This is different from most of the memblock
functions which are marked __init_memblock, and are only discarded after
boot if memory hotplug is not configured.
To allow for upcoming code which will need memblock_phys_mem_size() in
the hotplug path, change it from __init to __init_memblock.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some servers experienced fatal deadlocks because of a combination of
bugs, leading to multiple cpus calling dump_stack().
The checksumming bug was fixed in commit 34ae6a1aa0 ("ipv6: update
skb->csum when CE mark is propagated").
The second problem is a faulty locking in dump_stack()
CPU1 runs in process context and calls dump_stack(), grabs dump_lock.
CPU2 receives a TCP packet under softirq, grabs socket spinlock, and
call dump_stack() from netdev_rx_csum_fault().
dump_stack() spins on atomic_cmpxchg(&dump_lock, -1, 2), since
dump_lock is owned by CPU1
While dumping its stack, CPU1 is interrupted by a softirq, and happens
to process a packet for the TCP socket locked by CPU2.
CPU1 spins forever in spin_lock() : deadlock
Stack trace on CPU1 looked like :
NMI backtrace for cpu 1
RIP: _raw_spin_lock+0x25/0x30
...
Call Trace:
<IRQ>
tcp_v6_rcv+0x243/0x620
ip6_input_finish+0x11f/0x330
ip6_input+0x38/0x40
ip6_rcv_finish+0x3c/0x90
ipv6_rcv+0x2a9/0x500
process_backlog+0x461/0xaa0
net_rx_action+0x147/0x430
__do_softirq+0x167/0x2d0
call_softirq+0x1c/0x30
do_softirq+0x3f/0x80
irq_exit+0x6e/0xc0
smp_call_function_single_interrupt+0x35/0x40
call_function_single_interrupt+0x6a/0x70
<EOI>
printk+0x4d/0x4f
printk_address+0x31/0x33
print_trace_address+0x33/0x3c
print_context_stack+0x7f/0x119
dump_trace+0x26b/0x28e
show_trace_log_lvl+0x4f/0x5c
show_stack_log_lvl+0x104/0x113
show_stack+0x42/0x44
dump_stack+0x46/0x58
netdev_rx_csum_fault+0x38/0x3c
__skb_checksum_complete_head+0x6e/0x80
__skb_checksum_complete+0x11/0x20
tcp_rcv_established+0x2bd5/0x2fd0
tcp_v6_do_rcv+0x13c/0x620
sk_backlog_rcv+0x15/0x30
release_sock+0xd2/0x150
tcp_recvmsg+0x1c1/0xfc0
inet_recvmsg+0x7d/0x90
sock_recvmsg+0xaf/0xe0
___sys_recvmsg+0x111/0x3b0
SyS_recvmsg+0x5c/0xb0
system_call_fastpath+0x16/0x1b
Fixes: b58d977432 ("dump_stack: serialize the output from dump_stack()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
