Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
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Pull DeviceTree fixes from Rob Herring:
"Two small DT fixes:
- Fix error handling in of_irq_to_resource_table() due to
of_irq_to_resource() error return changes.
- Fix dtx_diff script due to dts include path changes"
* tag 'devicetree-fixes-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
of: irq: fix of_irq_to_resource() error check
scripts/dtc: dtx_diff - update include dts paths to match build
Pull NFS client fixes from Anna Schumaker:
"More NFS client bugfixes for 4.13.
Most of these fix locking bugs that Ben and Neil noticed, but I also
have a patch to fix one more access bug that was reported after last
week.
Stable fixes:
- Fix a race where CB_NOTIFY_LOCK fails to wake a waiter
- Invalidate file size when taking a lock to prevent corruption
Other fixes:
- Don't excessively generate tiny writes with fallocate
- Use the raw NFS access mask in nfs4_opendata_access()"
* tag 'nfs-for-4.13-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFSv4.1: Fix a race where CB_NOTIFY_LOCK fails to wake a waiter
NFS: Optimize fallocate by refreshing mapping when needed.
NFS: invalidate file size when taking a lock.
NFS: Use raw NFS access mask in nfs4_opendata_access()
of_irq_to_resource() has recently been fixed to return negative error #'s
along with 0, however of_irq_to_resource_table() still only regards 0 as
invalid IRQ -- fix it up.
Fixes: 7a4228bbff76 ("of: irq: use of_irq_get() in of_irq_to_resource()")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Pull xfs fixes from Darrick Wong:
- fix firstfsb variables that we left uninitialized, which could lead
to locking problems.
- check for NULL metadata buffer pointers before using them.
- don't allow btree cursor manipulation if the btree block is corrupt.
Better to just shut down.
- fix infinite loop problems in quotacheck.
- fix buffer overrun when validating directory blocks.
- fix deadlock problem in bunmapi.
* tag 'xfs-4.13-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix multi-AG deadlock in xfs_bunmapi
xfs: check that dir block entries don't off the end of the buffer
xfs: fix quotacheck dquot id overflow infinite loop
xfs: check _alloc_read_agf buffer pointer before using
xfs: set firstfsb to NULLFSBLOCK before feeding it to _bmapi_write
xfs: check _btree_check_block value
nfs4_retry_setlk() sets the task's state to TASK_INTERRUPTIBLE within the
same region protected by the wait_queue's lock after checking for a
notification from CB_NOTIFY_LOCK callback. However, after releasing that
lock, a wakeup for that task may race in before the call to
freezable_schedule_timeout_interruptible() and set TASK_WAKING, then
freezable_schedule_timeout_interruptible() will set the state back to
TASK_INTERRUPTIBLE before the task will sleep. The result is that the task
will sleep for the entire duration of the timeout.
Since we've already set TASK_INTERRUPTIBLE in the locked section, just use
freezable_schedule_timout() instead.
Fixes: a1d617d8f134 ("nfs: allow blocking locks to be awoken by lock callbacks")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Update the cpp include flags for compiling device tree dts files
to match the changes made to the kernel build process in
commit d5d332d3f7e8 ("devicetree: Move include prefixes from arch
to separate directory").
Cc: <stable@vger.kernel.org> # 4.12
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Pull KVM fixes from Paolo Bonzini:
"s390:
- SRCU fix
PPC:
- host crash fixes
x86:
- bugfixes, including making nested posted interrupts really work
Generic:
- tweaks to kvm_stat and to uevents"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: LAPIC: Fix reentrancy issues with preempt notifiers
tools/kvm_stat: add '-f help' to get the available event list
tools/kvm_stat: use variables instead of hard paths in help output
KVM: nVMX: Fix loss of L2's NMI blocking state
KVM: nVMX: Fix posted intr delivery when vcpu is in guest mode
x86: irq: Define a global vector for nested posted interrupts
KVM: x86: do mask out upper bits of PAE CR3
KVM: make pid available for uevents without debugfs
KVM: s390: take srcu lock when getting/setting storage keys
KVM: VMX: remove unused field
KVM: PPC: Book3S HV: Fix host crash on changing HPT size
KVM: PPC: Book3S HV: Enable TM before accessing TM registers
Just like in the allocator we must avoid touching multiple AGs out of
order when freeing blocks, as freeing still locks the AGF and can cause
the same AB-BA deadlocks as in the allocation path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
posix_fallocate() will allocate space in an NFS file by considering
the last byte of every 4K block. If it is before EOF, it will read
the byte and if it is zero, a zero is written out. If it is after EOF,
the zero is unconditionally written.
For the blocks beyond EOF, if NFS believes its cache is valid, it will
expand these writes to write full pages, and then will merge the pages.
This results if (typically) 1MB writes. If NFS believes its cache is
not valid (particularly if NFS_INO_INVALID_DATA or
NFS_INO_REVAL_PAGECACHE are set - see nfs_write_pageuptodate()), it will
send the individual 1-byte writes. This results in (typically) 256 times
as many RPC requests, and can be substantially slower.
Currently nfs_revalidate_mapping() is only used when reading a file or
mmapping a file, as these are times when the content needs to be
up-to-date. Writes don't generally need the cache to be up-to-date, but
writes beyond EOF can benefit, particularly in the posix_fallocate()
case.
So this patch calls nfs_revalidate_mapping() when writing beyond EOF -
i.e. when there is a gap between the end of the file and the start of
the write. If the cache is thought to be out of date (as happens after
taking a file lock), this will cause a GETATTR, and the two flags
mentioned above will be cleared. With this, posix_fallocate() on a
newly locked file does not generate excessive tiny writes.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Pull xen fixes from Juergen Gross:
"Three minor cleanups for xen related drivers"
* tag 'for-linus-4.13b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: dont fiddle with event channel masking in suspend/resume
xen: selfballoon: remove unnecessary static in frontswap_selfshrink()
xen: Drop un-informative message during boot
Two commits which fix host crashes.
Signed-off-by: Paolo BOnzini <pbonzini@redhat.com>
When we're checking the entries in a directory buffer, make sure that
the entry length doesn't push us off the end of the buffer. Found via
xfs/388 writing ones to the length fields.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>