And it should have gone in through the x86 tree :(
Reported-by: Colin King <colin.king@canonical.com> Reported-by: Ingo Molnar <mingo@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Joel Holdsworth [Wed, 14 Jun 2017 15:36:33 +0000 (10:36 -0500)]
of: Add vendor prefix for Lattice Semiconductor
Lattice Semiconductor Corporation is a manufacturer of integrated
circuits and IP products, including low-power FPGAs, video connectivity
devices and millimeter wave wireless products.
Website: http://latticesemi.com
Signed-off-by: Joel Holdsworth <joel@airwebreathe.org.uk> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Moritz Fischer <moritz.fischer@ettus.com> Signed-off-by: Alan Tull <atull@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fpga: Add flag to indicate SPI bitstream is bit-reversed
Add a flag that is passed to the write_init() callback,
indicating that the SPI bitstream starts with LSB first.
SPI controllers usually send data with MSB first. If an
FPGA expects bitstream data as LSB first, the data must
be reversed either by the SPI controller or by the driver.
Alternatively the bitstream could be prepared as bit-reversed
to avoid the bit-swapping while sending. This flag indicates
such bit-reversed SPI bitstream. The low-level driver will
deal with the flag and perform bit-reversing if needed.
charlcd_ops are not supposed to change at runtime. All functions
working with charlcd_ops provided by <misc/charlcd.h> work with
const charlcd_ops. So mark the non-const structs as const.
File size before:
text data bss dec hex filename
12750 560 362 13672 3568 drivers/auxdisplay/panel.o
File size After adding 'const':
text data bss dec hex filename
12942 368 362 13672 3568 drivers/auxdisplay/panel.o
Colin Ian King [Mon, 10 Jul 2017 15:08:32 +0000 (16:08 +0100)]
char/mwave: make some arrays static const to make object code smaller
Don't populate arrays on the stack but make them static. Makes
the object code smaller. Also remove temporary variables that
have hard coded array sizes and just use ARRAY_SIZE instead and
wrap some lines that are wider than 80 chars to clean up some
checkpatch warnings.
Before:
text data bss dec hex filename
11141 2008 64 13213 339d drivers/char/mwave/smapi.o
After:
text data bss dec hex filename
10697 2352 64 13113 3339 drivers/char/mwave/smapi.o
Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Vitaly Kuznetsov [Sun, 25 Jun 2017 17:06:41 +0000 (10:06 -0700)]
x86/hyper-v: stash the max number of virtual/logical processor
Max virtual processor will be needed for 'extended' hypercalls supporting
more than 64 vCPUs. While on it, unify on 'Hyper-V' in mshyperv.c as we
currently have a mix, report acquired misc features as well.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Vitaly Kuznetsov [Sun, 25 Jun 2017 17:06:40 +0000 (10:06 -0700)]
x86/hyper-v: include hyperv/ only when CONFIG_HYPERV is set
Code is arch/x86/hyperv/ is only needed when CONFIG_HYPERV is set, the
'basic' support and detection lives in arch/x86/kernel/cpu/mshyperv.c
which is included when CONFIG_HYPERVISOR_GUEST is set.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When iterating over incoming ring elements from the host, prefetch
the next descriptor so that it is cache hot.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't signal host if it has disabled interrupts for that
ring buffer. Check the feature bit to see if host supports
pending send size flag.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't need cached read index anymore now that packet iterator
is used. The iterator has the original read index until the
visible read_index is updated.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function hv_signal_on_read was defined in hyperv.h and
only used in one place in ring_buffer code. Clearer to just
move it inline there.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The elements ring_data_start_offset and priv_write_index
are not used.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With new iterator functions (and the double mapping) the ring buffer
read function can be greatly simplified.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Logan Gunthorpe [Fri, 16 Jun 2017 23:48:21 +0000 (17:48 -0600)]
block: order /proc/devices by major number
Presently, the order of the block devices listed in /proc/devices is not
entirely sequential. If a block device has a major number greater than
BLKDEV_MAJOR_HASH_SIZE (255), it will be ordered as if its major were
module 255. For example, 511 appears after 1.
This patch cleans that up and prints each major number in the correct
order, regardless of where they are stored in the hash table.
In order to do this, we introduce BLKDEV_MAJOR_MAX as an artificial
limit (chosen to be 512). It will then print all devices in major
order number from 0 to the maximum.
Logan Gunthorpe [Thu, 15 Jun 2017 20:05:21 +0000 (14:05 -0600)]
char_dev: order /proc/devices by major number
Presently, the order of the char devices listed in /proc/devices is not
entirely sequential. If a char device has a major number greater than
CHRDEV_MAJOR_HASH_SIZE (255), it will be ordered as if its major were
module 255. For example, 511 appears after 1.
This patch cleans that up and prints each major number in the correct
order, regardless of where they are stored in the hash table.
In order to do this, we introduce CHRDEV_MAJOR_MAX as an artificial
limit (chosen to be 511). It will then print all devices in major
order number from 0 to the maximum.
Logan Gunthorpe [Thu, 15 Jun 2017 20:05:20 +0000 (14:05 -0600)]
char_dev: extend dynamic allocation of majors into a higher range
We've run into problems with running out of dynamicly assign char
device majors particullarly on automated test systems with
all-yes-configs. Roughly 40 dynamic assignments can be made with such
kernels at this time while space is reserved for only 20.
Currently, the kernel only prints a warning when dynamic allocation
overflows the reserved region. And when this happens drivers that have
fixed assignments can randomly fail depending on the order of
initialization of other drivers. Thus, adding a new char device can cause
unexpected failures in completely unrelated parts of the kernel.
This patch solves the problem by extending dynamic major number
allocations down from 511 once the 234-254 region fills up. Fixed
majors already exist above 255 so the infrastructure to support
high number majors is already in place. The patch reserves an
additional 128 major numbers which should hopefully last us a while.
Kernels that don't require more than 20 dynamic majors assigned (which
is pretty typical) should not be affected by this change.
Tomas Winkler [Wed, 14 Jun 2017 07:03:15 +0000 (10:03 +0300)]
mei: me: use an index instead of a pointer for private data
Device 'new_id' interface is useful for testing of not yet published
hardware on older kernels and for internally used device ids on
simulation platforms.
However currently with the device configuration held in device_id driver
data as a pointer to mei_cfg structure it is hard, as one need to locate
the address of the correct structure.
A recommended way of doing that is to use and index instead of a
pointer.
This patch adds a new list of configuration mei_cfg_list[]
indexed via enum mei_cfg_idx.
In addition it cleanups ich platform naming, renames legacy
generation to ich and what was ich to ich10.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some platforms, currently Broxton, Apollo Lake and Kaby Lake,
ME FW may be busy with internal bookkeeping and answering late
to the start message.
As a mitigation, the driver requests for a synchronous probing
to prevent stalling of the overall boot process. For example,
on a Apollo Lake platform the overall boot time has reduced from
~0.9 to ~0.6 seconds on average.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Martijn Coenen [Thu, 29 Jun 2017 19:02:10 +0000 (12:02 -0700)]
binder: fix death race conditions
A race existed where one thread could register
a death notification for a node, while another
thread was cleaning up that node and sending
out death notifications for its references,
causing simultaneous access to ref->death
because different locks were held.
Todd Kjos [Thu, 29 Jun 2017 19:02:09 +0000 (12:02 -0700)]
binder: protect against stale pointers in print_binder_transaction
When printing transactions there were several race conditions
that could cause a stale pointer to be deferenced. Fixed by
reading the pointer once and using it if valid (which is
safe). The transaction buffer also needed protection via proc
lock, so it is only printed if we are holding the correct lock.
Todd Kjos [Thu, 29 Jun 2017 19:02:08 +0000 (12:02 -0700)]
binder: protect binder_ref with outer lock
Use proc->outer_lock to protect the binder_ref structure.
The outer lock allows functions operating on the binder_ref
to do nested acquires of node and inner locks as necessary
to attach refs to nodes atomically.
Binder refs must never be accesssed without holding the
outer lock.
Martijn Coenen [Thu, 29 Jun 2017 19:02:06 +0000 (12:02 -0700)]
binder: protect transaction_stack with inner lock.
This makes future changes to priority inheritance
easier, since we want to be able to look at a thread's
transaction stack when selecting a thread to inherit
priority for.
It also allows us to take just a single lock in a
few paths, where we used to take two in succession.
Todd Kjos [Thu, 29 Jun 2017 19:02:05 +0000 (12:02 -0700)]
binder: protect proc->threads with inner_lock
proc->threads will need to be accessed with higher
locks of other processes held so use proc->inner_lock
to protect it. proc->tmp_ref now needs to be protected
by proc->inner_lock.
Todd Kjos [Thu, 29 Jun 2017 19:02:02 +0000 (12:02 -0700)]
binder: add spinlocks to protect todo lists
The todo lists in the proc, thread, and node structures
are accessed by other procs/threads to place work
items on the queue.
The todo lists are protected by the new proc->inner_lock.
No locks should ever be nested under these locks. As the
name suggests, an outer lock will be introduced in
a later patch.
Todd Kjos [Thu, 29 Jun 2017 19:02:01 +0000 (12:02 -0700)]
binder: use inner lock to sync work dq and node counts
For correct behavior we need to hold the inner lock when
dequeuing and processing node work in binder_thread_read.
We now hold the inner lock when we enter the switch statement
and release it after processing anything that might be
affected by other threads.
We also need to hold the inner lock to protect the node
weak/strong ref tracking fields as long as node->proc
is non-NULL (if it is NULL then we are guaranteed that
we don't have any node work queued).
This means that other functions that manipulate these fields
must hold the inner lock. Refactored these functions to use
the inner lock.
Todd Kjos [Thu, 29 Jun 2017 19:02:00 +0000 (12:02 -0700)]
binder: introduce locking helper functions
There are 3 main spinlocks which must be acquired in this
order:
1) proc->outer_lock : protects most fields of binder_proc,
binder_thread, and binder_ref structures. binder_proc_lock()
and binder_proc_unlock() are used to acq/rel.
2) node->lock : protects most fields of binder_node.
binder_node_lock() and binder_node_unlock() are
used to acq/rel
3) proc->inner_lock : protects the thread and node lists
(proc->threads, proc->nodes) and all todo lists associated
with the binder_proc (proc->todo, thread->todo,
proc->delivered_death and node->async_todo).
binder_inner_proc_lock() and binder_inner_proc_unlock()
are used to acq/rel
Any lock under procA must never be nested under any lock at the same
level or below on procB.
Functions that require a lock held on entry indicate which lock
in the suffix of the function name:
Todd Kjos [Thu, 29 Jun 2017 19:01:59 +0000 (12:01 -0700)]
binder: use node->tmp_refs to ensure node safety
When obtaining a node via binder_get_node(),
binder_get_node_from_ref() or binder_new_node(),
increment node->tmp_refs to take a
temporary reference on the node to ensure the node
persists while being used. binder_put_node() must
be called to remove the temporary reference.
Todd Kjos [Thu, 29 Jun 2017 19:01:58 +0000 (12:01 -0700)]
binder: refactor binder ref inc/dec for thread safety
Once locks are added, binder_ref's will only be accessed
safely with the proc lock held. Refactor the inc/dec paths
to make them atomic with the binder_get_ref* paths and
node inc/dec. For example, instead of:
Todd Kjos [Thu, 29 Jun 2017 19:01:57 +0000 (12:01 -0700)]
binder: make sure accesses to proc/thread are safe
binder_thread and binder_proc may be accessed by other
threads when processing transaction. Therefore they
must be prevented from being freed while a transaction
is in progress that references them.
This is done by introducing a temporary reference
counter for threads and procs that indicates that the
object is in use and must not be freed. binder_thread_dec_tmpref()
and binder_proc_dec_tmpref() are used to decrement
the temporary reference.
It is safe to free a binder_thread if there
is no reference and it has been released
(indicated by thread->is_dead).
It is safe to free a binder_proc if it has no
remaining threads and no reference.
A spinlock is added to the binder_transaction
to safely access and set references for t->from
and for debug code to safely access t->to_thread
and t->to_proc.
Todd Kjos [Thu, 29 Jun 2017 19:01:56 +0000 (12:01 -0700)]
binder: make sure target_node has strong ref
When initiating a transaction, the target_node must
have a strong ref on it. Then we take a second
strong ref to make sure the node survives until the
transaction is complete.
Since errors are tracked in the return_error/return_error2
fields of the binder_thread object and BR_TRANSACTION_COMPLETEs
can be tracked either in those fields or via the thread todo
work list, it is possible for errors to be reported ahead
of the associated txn complete.
Use the thread todo work list for errors to guarantee
order. Also changed binder_send_failed_reply to pop
the transaction even if it failed to send a reply.
Todd Kjos [Thu, 29 Jun 2017 19:01:54 +0000 (12:01 -0700)]
binder: refactor binder_pop_transaction
binder_pop_transaction needs to be split into 2 pieces to
to allow the proc lock to be held on entry to dequeue the
transaction stack, but no lock when kfree'ing the transaction.
Split into binder_pop_transaction_locked and binder_free_transaction
(the actual locks are still to be added).
Todd Kjos [Thu, 29 Jun 2017 19:01:53 +0000 (12:01 -0700)]
binder: use atomic for transaction_log index
The log->next index for the transaction log was
not protected when incremented. This led to a
case where log->next++ resulted in an index
larger than ARRAY_SIZE(log->entry) and eventually
a bad access to memory.
Fixed by making the log index an atomic64 and
converting to an array by using "% ARRAY_SIZE(log->entry)"
Also added "complete" field to the log entry which is
written last to tell the print code whether the
entry is complete
Todd Kjos [Thu, 29 Jun 2017 19:01:49 +0000 (12:01 -0700)]
binder: don't modify thread->looper from other threads
The looper member of struct binder_thread is a bitmask
of control bits. All of the existing bits are modified
by the affected thread except for BINDER_LOOPER_STATE_NEED_RETURN
which can be modified in binder_deferred_flush() by
another thread.
To avoid adding a spinlock around all read-mod-writes to
modify a bit, the BINDER_LOOPER_STATE_NEED_RETURN flag
is replaced by a separate field in struct binder_thread.
Todd Kjos [Thu, 29 Jun 2017 19:01:48 +0000 (12:01 -0700)]
binder: avoid race conditions when enqueuing txn
Currently, the transaction complete work item is queued
after the transaction. This means that it is possible
for the transaction to be handled and a reply to be
enqueued in the current thread before the transaction
complete is enqueued, which violates the protocol
with userspace who may not expect the transaction
complete. Fixed by always enqueing the transaction
complete first.
Also, once the transaction is enqueued, it is unsafe
to access since it might be freed. Currently,
t->flags is accessed to determine whether a sync
wake is needed. Changed to access tr->flags
instead.
Todd Kjos [Thu, 29 Jun 2017 19:01:47 +0000 (12:01 -0700)]
binder: refactor queue management in binder_thread_read
In binder_thread_read, the BINDER_WORK_NODE command is used
to communicate the references on the node to userspace. It
can take a couple of iterations in the loop to construct
the list of commands for user space. When locking is added,
the lock would need to be release on each iteration which
means the state could change. The work item is not dequeued
during this process which prevents a simpler queue management
that can just dequeue up front and handle the work item.
Fixed by changing the BINDER_WORK_NODE algorithm in
binder_thread_read to determine which commands to send
to userspace atomically in 1 pass so it stays consistent
with the kernel view.
The work item is now dequeued immediately since only
1 pass is needed.
Todd Kjos [Thu, 29 Jun 2017 19:01:46 +0000 (12:01 -0700)]
binder: add log information for binder transaction failures
Add additional information to determine the cause of binder
failures. Adds the following to failed transaction log and
kernel messages:
return_error : value returned for transaction
return_error_param : errno returned by binder allocator
return_error_line : line number where error detected
Also, return BR_DEAD_REPLY if an allocation error indicates
a dead proc (-ESRCH)
Todd Kjos [Thu, 29 Jun 2017 19:01:42 +0000 (12:01 -0700)]
binder: remove binder_debug_no_lock mechanism
With the global lock, there was a mechanism to access
binder driver debugging information with the global
lock disabled to debug deadlocks or other issues.
This mechanism is rarely (if ever) used anymore
and wasn't needed during the development of
fine-grained locking in the binder driver.
Removing it.
Todd Kjos [Thu, 29 Jun 2017 19:01:40 +0000 (12:01 -0700)]
binder: separate out binder_alloc functions
Continuation of splitting the binder allocator from the binder
driver. Separate binder_alloc functions from normal binder
functions. Protect the allocator with a separate mutex.
Todd Kjos [Thu, 29 Jun 2017 19:01:38 +0000 (12:01 -0700)]
binder: separate binder allocator structure from binder proc
The binder allocator is logically separate from the rest
of the binder drivers. Separating the data structures
to prepare for splitting into separate file with separate
locking.
Riley Andrews [Thu, 29 Jun 2017 19:01:37 +0000 (12:01 -0700)]
binder: Use wake up hint for synchronous transactions.
Use wake_up_interruptible_sync() to hint to the scheduler binder
transactions are synchronous wakeups. Disable preemption while waking
to avoid ping-ponging on the binder lock.
Todd Kjos [Thu, 29 Jun 2017 19:01:36 +0000 (12:01 -0700)]
binder: use group leader instead of open thread
The binder allocator assumes that the thread that
called binder_open will never die for the lifetime of
that proc. That thread is normally the group_leader,
however it may not be. Use the group_leader instead
of current.
The patch introduced a race in the binder driver. An attempt to fix the
race was submitted in "[PATCH v2] android: binder: fix dangling pointer
comparison", however the conclusion in the discussion for that patch
was that the original patch should be reverted.
The reversion is being done as part of the fine-grained locking
patchset since the patch would need to be refactored when
proc->vmm_vm_mm is removed from struct binder_proc and added
in the binder allocator.
Merge tag 'standardize-docs' of git://git.lwn.net/linux
Pull documentation format standardization from Jonathan Corbet:
"This series converts a number of top-level documents to the RST format
without incorporating them into the Sphinx tree. The hope is to bring
some uniformity to kernel documentation and, perhaps more importantly,
have our existing docs serve as an example of the desired formatting
for those that will be added later.
Mauro has gone through and fixed up a lot of top-level documentation
files to make them conform to the RST format, but without moving or
renaming them in any way. This will help when we incorporate the ones
we want to keep into the Sphinx doctree, but the real purpose is to
bring a bit of uniformity to our documentation and let the top-level
docs serve as examples for those writing new ones"
* tag 'standardize-docs' of git://git.lwn.net/linux: (84 commits)
docs: kprobes.txt: Fix whitespacing
tee.txt: standardize document format
cgroup-v2.txt: standardize document format
dell_rbu.txt: standardize document format
zorro.txt: standardize document format
xz.txt: standardize document format
xillybus.txt: standardize document format
vfio.txt: standardize document format
vfio-mediated-device.txt: standardize document format
unaligned-memory-access.txt: standardize document format
this_cpu_ops.txt: standardize document format
svga.txt: standardize document format
static-keys.txt: standardize document format
smsc_ece1099.txt: standardize document format
SM501.txt: standardize document format
siphash.txt: standardize document format
sgi-ioc4.txt: standardize document format
SAK.txt: standardize document format
rpmsg.txt: standardize document format
robust-futexes.txt: standardize document format
...
Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random
Pull random updates from Ted Ts'o:
"Add wait_for_random_bytes() and get_random_*_wait() functions so that
callers can more safely get random bytes if they can block until the
CRNG is initialized.
Also print a warning if get_random_*() is called before the CRNG is
initialized. By default, only one single-line warning will be printed
per boot. If CONFIG_WARN_ALL_UNSEEDED_RANDOM is defined, then a
warning will be printed for each function which tries to get random
bytes before the CRNG is initialized. This can get spammy for certain
architecture types, so it is not enabled by default"
* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
random: reorder READ_ONCE() in get_random_uXX
random: suppress spammy warnings about unseeded randomness
random: warn when kernel uses unseeded randomness
net/route: use get_random_int for random counter
net/neighbor: use get_random_u32 for 32-bit hash random
rhashtable: use get_random_u32 for hash_rnd
ceph: ensure RNG is seeded before using
iscsi: ensure RNG is seeded before use
cifs: use get_random_u32 for 32-bit lock random
random: add get_random_{bytes,u32,u64,int,long,once}_wait family
random: add wait_for_random_bytes() API
Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull ->s_options removal from Al Viro:
"Preparations for fsmount/fsopen stuff (coming next cycle). Everything
gets moved to explicit ->show_options(), killing ->s_options off +
some cosmetic bits around fs/namespace.c and friends. Basically, the
stuff needed to work with fsmount series with minimum of conflicts
with other work.
It's not strictly required for this merge window, but it would reduce
the PITA during the coming cycle, so it would be nice to have those
bits and pieces out of the way"
* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
isofs: Fix isofs_show_options()
VFS: Kill off s_options and helpers
orangefs: Implement show_options
9p: Implement show_options
isofs: Implement show_options
afs: Implement show_options
affs: Implement show_options
befs: Implement show_options
spufs: Implement show_options
bpf: Implement show_options
ramfs: Implement show_options
pstore: Implement show_options
omfs: Implement show_options
hugetlbfs: Implement show_options
VFS: Don't use save/replace_mount_options if not using generic_show_options
VFS: Provide empty name qstr
VFS: Make get_filesystem() return the affected filesystem
VFS: Clean up whitespace in fs/namespace.c and fs/super.c
Provide a function to create a NUL-terminated string from unterminated data
Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uacess-unaligned removal from Al Viro:
"That stuff had just one user, and an exotic one, at that - binfmt_flat
on arm and m68k"
* 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
kill {__,}{get,put}_user_unaligned()
binfmt_flat: flat_{get,put}_addr_from_rp() should be able to fail
Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull network field-by-field copy-in updates from Al Viro:
"This part of the misc compat queue was held back for review from
networking folks and since davem has jus ACKed those..."
* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
get_compat_bpf_fprog(): don't copyin field-by-field
get_compat_msghdr(): get rid of field-by-field copyin
copy_msghdr_from_user(): get rid of field-by-field copyin
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
"Boston platform support:
- Document DT bindings
- Add CLK driver for board clocks
CM:
- Avoid per-core locking with CM3 & higher
- WARN on attempt to lock invalid VP, not BUG
CPS:
- Select CONFIG_SYS_SUPPORTS_SCHED_SMT for MIPSr6
- Prevent multi-core with dcache aliasing
- Handle cores not powering down more gracefully
- Handle spurious VP starts more gracefully
DSP:
- Add lwx & lhx missaligned access support
eBPF:
- Add MIPS support along with many supporting change to add the
required infrastructure
Generic arch code:
- Misc sysmips MIPS_ATOMIC_SET fixes
- Drop duplicate HAVE_SYSCALL_TRACEPOINTS
- Negate error syscall return in trace
- Correct forced syscall errors
- Traced negative syscalls should return -ENOSYS
- Allow samples/bpf/tracex5 to access syscall arguments for sane
traces
- Cleanup from old Kconfig options in defconfigs
- Fix PREF instruction usage by memcpy for MIPS R6
- Fix various special cases in the FPU eulation
- Fix some special cases in MIPS16e2 support
- Fix MIPS I ISA /proc/cpuinfo reporting
- Sort MIPS Kconfig alphabetically
- Fix minimum alignment requirement of IRQ stack as required by
ABI / GCC
- Fix special cases in the module loader
- Perform post-DMA cache flushes on systems with MAARs
- Probe the I6500 CPU
- Cleanup cmpxchg and add support for 1 and 2 byte operations
- Use queued read/write locks (qrwlock)
- Use queued spinlocks (qspinlock)
- Add CPU shared FTLB feature detection
- Handle tlbex-tlbp race condition
- Allow storing pgd in C0_CONTEXT for MIPSr6
- Use current_cpu_type() in m4kc_tlbp_war()
- Support Boston in the generic kernel
Generic platform:
- yamon-dt: Pull YAMON DT shim code out of SEAD-3 board
- yamon-dt: Support > 256MB of RAM
- yamon-dt: Use serial* rather than uart* aliases
- Abstract FDT fixup application
- Set RTC_ALWAYS_BCD to 0
- Add a MAINTAINERS entry
core kernel:
- qspinlock.c: include linux/prefetch.h
Loongson 3:
- Add support
Perf:
- Add I6500 support
SEAD-3:
- Remove GIC timer from DT
- Set interrupt-parent per-device, not at root node
- Fix GIC interrupt specifiers
SMP:
- Skip IPI setup if we only have a single CPU
VDSO:
- Make comment match reality
- Improvements to time code in VDSO"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (86 commits)
locking/qspinlock: Include linux/prefetch.h
MIPS: Fix MIPS I ISA /proc/cpuinfo reporting
MIPS: Fix minimum alignment requirement of IRQ stack
MIPS: generic: Support MIPS Boston development boards
MIPS: DTS: img: Don't attempt to build-in all .dtb files
clk: boston: Add a driver for MIPS Boston board clocks
dt-bindings: Document img,boston-clock binding
MIPS: Traced negative syscalls should return -ENOSYS
MIPS: Correct forced syscall errors
MIPS: Negate error syscall return in trace
MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select
MIPS16e2: Provide feature overrides for non-MIPS16 systems
MIPS: MIPS16e2: Report ASE presence in /proc/cpuinfo
MIPS: MIPS16e2: Subdecode extended LWSP/SWSP instructions
MIPS: MIPS16e2: Identify ASE presence
MIPS: VDSO: Fix a mismatch between comment and preprocessor constant
MIPS: VDSO: Add implementation of gettimeofday() fallback
MIPS: VDSO: Add implementation of clock_gettime() fallback
MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse()
MIPS: Use current_cpu_type() in m4kc_tlbp_war()
...
Merge branch 'for-linus-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
"Mostly fixes for UML:
- First round of fixes for PTRACE_GETRESET/SETREGSET
- A printf vs printk cleanup
- Minor improvements"
* 'for-linus-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Correctly check for PTRACE_GETRESET/SETREGSET
um: v2: Use generic NOTES macro
um: Add kerneldoc for userspace_tramp() and start_userspace()
um: Add kerneldoc for segv_handler
um: stub-data.h: remove superfluous include
um: userspace - be more verbose in ptrace set regs error
um: add dummy ioremap and iounmap functions
um: Allow building and running on older hosts
um: Avoid longjmp/setjmp symbol clashes with libpthread.a
um: console: Ignore console= option
um: Use os_warn to print out pre-boot warning/error messages
um: Add os_warn() for pre-boot warning/error messages
um: Use os_info for the messages on normal path
um: Add os_info() for pre-boot information messages
um: Use printk instead of printf in make_uml_dir
Merge tag 'upstream-4.13-rc1' of git://git.infradead.org/linux-ubifs
Pull UBIFS updates from Richard Weinberger:
- Updates and fixes for the file encryption mode
- Minor improvements
- Random fixes
* tag 'upstream-4.13-rc1' of git://git.infradead.org/linux-ubifs:
ubifs: Set double hash cookie also for RENAME_EXCHANGE
ubifs: Massage assert in ubifs_xattr_set() wrt. init_xattrs
ubifs: Don't leak kernel memory to the MTD
ubifs: Change gfp flags in page allocation for bulk read
ubifs: Fix oops when remounting with no_bulk_read.
ubifs: Fail commit if TNC is obviously inconsistent
ubifs: allow userspace to map mounts to volumes
ubifs: Wire-up statx() support
ubifs: Remove dead code from ubifs_get_link()
ubifs: Massage debug prints wrt. fscrypt
ubifs: Add assert to dent_key_init()
ubifs: Fix unlink code wrt. double hash lookups
ubifs: Fix data node size for truncating uncompressed nodes
ubifs: Don't encrypt special files on creation
ubifs: Fix memory leak in RENAME_WHITEOUT error path in do_rename
ubifs: Fix inode data budget in ubifs_mknod
ubifs: Correctly evict xattr inodes
ubifs: Unexport ubifs_inode_slab
ubifs: don't bother checking for encryption key in ->mmap()
ubifs: require key for truncate(2) of encrypted file
Merge tag 'kvm-4.13-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Radim Krčmář:
"Second batch of KVM updates for v4.13
Common:
- add uevents for VM creation/destruction
- annotate and properly access RCU-protected objects
s390:
- rename IOCTL added in the first v4.13 merge
x86:
- emulate VMLOAD VMSAVE feature in SVM
- support paravirtual asynchronous page fault while nested
- add Hyper-V userspace interfaces for better migration
- improve master clock corner cases
- extend internal error reporting after EPT misconfig
- correct single-stepping of emulated instructions in SVM
- handle MCE during VM entry
- fix nVMX VM entry checks and nVMX VMCS shadowing"
* tag 'kvm-4.13-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
kvm: x86: hyperv: make VP_INDEX managed by userspace
KVM: async_pf: Let guest support delivery of async_pf from guest mode
KVM: async_pf: Force a nested vmexit if the injected #PF is async_pf
KVM: async_pf: Add L1 guest async_pf #PF vmexit handler
KVM: x86: Simplify kvm_x86_ops->queue_exception parameter list
kvm: x86: hyperv: add KVM_CAP_HYPERV_SYNIC2
KVM: x86: make backwards_tsc_observed a per-VM variable
KVM: trigger uevents when creating or destroying a VM
KVM: SVM: Enable Virtual VMLOAD VMSAVE feature
KVM: SVM: Add Virtual VMLOAD VMSAVE feature definition
KVM: SVM: Rename lbr_ctl field in the vmcb control area
KVM: SVM: Prepare for new bit definition in lbr_ctl
KVM: SVM: handle singlestep exception when skipping emulated instructions
KVM: x86: take slots_lock in kvm_free_pit
KVM: s390: Fix KVM_S390_GET_CMMA_BITS ioctl definition
kvm: vmx: Properly handle machine check during VM-entry
KVM: x86: update master clock before computing kvmclock_offset
kvm: nVMX: Shadow "high" parts of shadowed 64-bit VMCS fields
kvm: nVMX: Fix nested_vmx_check_msr_bitmap_controls
kvm: nVMX: Validate the I/O bitmaps on nested VM-entry
...
Avoid the READ_ONCE in commit 4a072c71f49b ("random: silence compiler
warnings and fix race") if we can leave the function after
arch_get_random_XXX().
Cc: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Theodore Ts'o [Thu, 8 Jun 2017 08:16:59 +0000 (04:16 -0400)]
random: suppress spammy warnings about unseeded randomness
Unfortunately, on some models of some architectures getting a fully
seeded CRNG is extremely difficult, and so this can result in dmesg
getting spammed for a surprisingly long time. This is really bad from
a security perspective, and so architecture maintainers really need to
do what they can to get the CRNG seeded sooner after the system is
booted. However, users can't do anything actionble to address this,
and spamming the kernel messages log will only just annoy people.
For developers who want to work on improving this situation,
CONFIG_WARN_UNSEEDED_RANDOM has been renamed to
CONFIG_WARN_ALL_UNSEEDED_RANDOM. By default the kernel will always
print the first use of unseeded randomness. This way, hopefully the
security obsessed will be happy that there is _some_ indication when
the kernel boots there may be a potential issue with that architecture
or subarchitecture. To see all uses of unseeded randomness,
developers can enable CONFIG_WARN_ALL_UNSEEDED_RANDOM.
Merge tag 'xfs-4.13-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull XFS fixes from Darrick Wong:
"Largely debugging and regression fixes.
- Add some locking assertions for the _ilock helpers.
- Revert the XFS_QMOPT_NOLOCK patch; after discussion with hch the
online fsck patch that would have needed it has been redesigned and
no longer needs it.
- Fix behavioral regression of SEEK_HOLE/DATA with negative offsets
to match 4.12-era XFS behavior"
* tag 'xfs-4.13-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
vfs: in iomap seek_{hole,data}, return -ENXIO for negative offsets
Revert "xfs: grab dquots without taking the ilock"
xfs: assert locking precondition in xfs_readlink_bmap_ilocked
xfs: assert locking precondіtion in xfs_attr_list_int_ilocked
xfs: fixup xfs_attr_get_ilocked
Merge branch 'for-4.13-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"We've identified and fixed a silent corruption (introduced by code in
the first pull), a fixup after the blk_status_t merge and two fixes to
incremental send that Filipe has been hunting for some time"
* 'for-4.13-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix unexpected return value of bio_readpage_error
btrfs: btrfs_create_repair_bio never fails, skip error handling
btrfs: cloned bios must not be iterated by bio_for_each_segment_all
Btrfs: fix write corruption due to bio cloning on raid5/6
Btrfs: incremental send, fix invalid memory access
Btrfs: incremental send, fix invalid path for link commands
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull a few more input updates from Dmitry Torokhov:
- multi-touch handling for Xen
- fix for long-standing bug causing crashes in i8042 on boot
- change to gpio_keys to better handle key presses during system state
transition
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: i8042 - fix crash at boot time
Input: gpio_keys - handle the missing key press event in resume phase
Input: xen-kbdfront - add multi-touch support
Merge tag 'devprop-fix-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull device properties framework fix from Rafael Wysocki:
"This fixes a problem with bool properties that could be seen as "true"
when the property was not present at all by adding a special helper
for bool properties with checks for all of the requisute conditions
(Sakari Ailus)"
* tag 'devprop-fix-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
device property: Introduce fwnode_call_bool_op() for ops that return bool
Merge tag 'acpi-fixes-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes from Rafael Wysocki:
"These fix the return value of an IRQ mapping routine in the ACPI core,
fix an EC driver issue causing abnormal fan behavior after system
resume on some systems and add quirks for ACPI device objects that
need to be treated as "always present" to work around bogus
implementations of the _STA control method.
Specifics:
- Fix the return value of acpi_gsi_to_irq() to make the GSI to IRQ
mapping work on the Mustang (ARM64) platform (Mark Salter).
- Fix an EC driver issue that causes fans to behave abnormally after
system resume on some systems which turns out to be related to
switching over the EC into the polling mode during the noirq stages
of system suspend and resume (Lv Zheng).
- Add quirks for ACPI device objects that need to be treated as
"always present", because their _STA methods are designed to work
around Windows driver bugs and return garbage from our perspective
(Hans de Goede)"
* tag 'acpi-fixes-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / x86: Add KIOX000A accelerometer on GPD win to always_present_ids array
ACPI / x86: Add Dell Venue 11 Pro 7130 touchscreen to always_present_ids
ACPI / x86: Allow matching always_present_id array entries by DMI
Revert "ACPI / EC: Enable event freeze mode..." to fix a regression
ACPI / EC: Drop EC noirq hooks to fix a regression
ACPI / irq: Fix return code of acpi_gsi_to_irq()
Merge tag 'pm-fixes-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix a recently exposed issue in the PCI device wakeup code and
one older problem related to PCI device wakeup that has been reported
recently, modify one more piece of computations in intel_pstate to get
rid of a rounding error, fix a possible race in the schedutil cpufreq
governor, fix the device PM QoS sysfs interface to correctly handle
invalid user input, fix return values of two probe routines in devfreq
drivers and constify an attribute_group structure in devfreq.
Specifics:
- Avoid clearing the PCI PME Enable bit for devices as a result of
config space restoration which confuses AML executed afterward and
causes wakeup events to be lost on some systems (Rafael Wysocki).
- Fix the native PCIe PME interrupts handling in the cases when the
PME IRQ is set up as a system wakeup one so that runtime PM remote
wakeup works as expected after system resume on systems where that
happens (Rafael Wysocki).
- Fix the device PM QoS sysfs interface to handle invalid user input
correctly instead of using an unititialized variable value as the
latency tolerance for the device at hand (Dan Carpenter).
- Get rid of one more rounding error from intel_pstate computations
(Srinivas Pandruvada).
- Fix the schedutil cpufreq governor to prevent it from possibly
accessing unititialized data structures from governor callbacks in
some cases on systems when multiple CPUs share a single cpufreq
policy object (Vikram Mulukutla).
- Fix the return values of probe routines in two devfreq drivers
(Gustavo Silva).
- Constify an attribute_group structure in devfreq (Arvind Yadav)"
* tag 'pm-fixes-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PCI / PM: Fix native PME handling during system suspend/resume
PCI / PM: Restore PME Enable after config space restoration
cpufreq: schedutil: Fix sugov_start() versus sugov_update_shared() race
PM / QoS: return -EINVAL for bogus strings
cpufreq: intel_pstate: Fix ratio setting for min_perf_pct
PM / devfreq: constify attribute_group structures.
PM / devfreq: tegra: fix error return code in tegra_devfreq_probe()
PM / devfreq: rk3399_dmc: fix error return code in rk3399_dmcfreq_probe()
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
kmod: throttle kmod thread limit
kmod: add test driver to stress test the module loader
MAINTAINERS: give kmod some maintainer love
xtensa: use generic fb.h
fault-inject: add /proc/<pid>/fail-nth
fault-inject: simplify access check for fail-nth
fault-inject: make fail-nth read/write interface symmetric
fault-inject: parse as natural 1-based value for fail-nth write interface
fault-inject: automatically detect the number base for fail-nth write interface
kernel/watchdog.c: use better pr_fmt prefix
MAINTAINERS: move the befs tree to kernel.org
lib/atomic64_test.c: add a test that atomic64_inc_not_zero() returns an int
mm: fix overflow check in expand_upwards()
Daniel Micay [Fri, 14 Jul 2017 21:28:12 +0000 (17:28 -0400)]
replace incorrect strscpy use in FORTIFY_SOURCE
Using strscpy was wrong because FORTIFY_SOURCE is passing the maximum
possible size of the outermost object, but strscpy defines the count
parameter as the exact buffer size, so this could copy past the end of
the source. This would still be wrong with the planned usage of
__builtin_object_size(p, 1) for intra-object overflow checks since it's
the maximum possible size of the specified object with no guarantee of
it being that large.
Reuse of the fortified functions like this currently makes the runtime
error reporting less precise but that can be improved later on.
Noticed by Dave Jones and KASAN.
Signed-off-by: Daniel Micay <danielmicay@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Reported-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull arch/tile updates from Chris Metcalf:
"This adds support for an <arch/intreg.h> to help with removing
__need_xxx #defines from glibc, and removes some dead code in
arch/tile/mm/init.c"
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
mm, tile: drop arch_{add,remove}_memory
tile: prefer <arch/intreg.h> to __need_int_reg_t
Merge tag 'powerpc-4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Nothing that really stands out, just a bunch of fixes that have come
in in the last couple of weeks.
None of these are actually fixes for code that is new in 4.13. It's
roughly half older bugs, with fixes going to stable, and half
fixes/updates for Power9.
Thanks to: Aneesh Kumar K.V, Anton Blanchard, Balbir Singh, Benjamin
Herrenschmidt, Madhavan Srinivasan, Michael Neuling, Nicholas Piggin,
Oliver O'Halloran"
* tag 'powerpc-4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64: Fix atomic64_inc_not_zero() to return an int
powerpc: Fix emulation of mfocrf in emulate_step()
powerpc: Fix emulation of mcrf in emulate_step()
powerpc/perf: Add POWER9 alternate PM_RUN_CYC and PM_RUN_INST_CMPL events
powerpc/perf: Fix SDAR_MODE value for continous sampling on Power9
powerpc/asm: Mark cr0 as clobbered in mftb()
powerpc/powernv: Fix local TLB flush for boot and MCE on POWER9
powerpc/mm/radix: Synchronize updates to the process table
powerpc/mm/radix: Properly clear process table entry
powerpc/powernv: Tell OPAL about our MMU mode on POWER9
powerpc/kexec: Fix radix to hash kexec due to IAMR/AMOR
If we reach the limit of modprobe_limit threads running the next
request_module() call will fail. The original reason for adding a kill
was to do away with possible issues with in old circumstances which would
create a recursive series of request_module() calls.
We can do better than just be super aggressive and reject calls once we've
reached the limit by simply making pending callers wait until the
threshold has been reduced, and then throttling them in, one by one.
This throttling enables requests over the kmod concurrent limit to be
processed once a pending request completes. Only the first item queued up
to wait is woken up. The assumption here is once a task is woken it will
have no other option to also kick the queue to check if there are more
pending tasks -- regardless of whether or not it was successful.
By throttling and processing only max kmod concurrent tasks we ensure we
avoid unexpected fatal request_module() calls, and we keep memory
consumption on module loading to a minimum.
With x86_64 qemu, with 4 cores, 4 GiB of RAM it takes the following run
time to run both tests:
time ./kmod.sh -t 0008
real 0m16.366s
user 0m0.883s
sys 0m8.916s
time ./kmod.sh -t 0009
real 0m50.803s
user 0m0.791s
sys 0m9.852s
Link: http://lkml.kernel.org/r/20170628223155.26472-4-mcgrof@kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Jessica Yu <jeyu@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michal Marek <mmarek@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kmod: add test driver to stress test the module loader
This adds a new stress test driver for kmod: the kernel module loader.
The new stress test driver, test_kmod, is only enabled as a module right
now. It should be possible to load this as built-in and load tests
early (refer to the force_init_test module parameter), however since a
lot of test can get a system out of memory fast we leave this disabled
for now.
Using a system with 1024 MiB of RAM can *easily* get your kernel OOM
fast with this test driver.
The test_kmod driver exposes API knobs for us to fine tune simple
request_module() and get_fs_type() calls. Since these API calls only
allow each one parameter a test driver for these is rather simple.
Other factors that can help out test driver though are the number of
calls we issue and knowing current limitations of each. This exposes
configuration as much as possible through userspace to be able to build
tests directly from userspace.
Since it allows multiple misc devices its will eventually (once we add a
knob to let us create new devices at will) also be possible to perform
more tests in parallel, provided you have enough memory.
We only enable tests we know work as of right now.
0001 - Simple test - 1 thread for empty string
0002 - Simple test - 1 thread for modules/filesystems that do not exist
0003 - Simple test - 1 thread for get_fs_type() only
0004 - Simple test - 2 threads for get_fs_type() only
0005 - multithreaded tests with default setup - request_module() only
0006 - multithreaded tests with default setup - get_fs_type() only
0007 - multithreaded tests with default setup test request_module() and get_fs_type()
0008 - multithreaded - push kmod_concurrent over max_modprobes for request_module()
0009 - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()
The following test cases currently fail, as such they are not currently
enabled by default:
To be sure to run them as intended please unload both of the modules:
o test_module
o xfs
And ensure they are not loaded on your system prior to testing them. If
you use these paritions for your rootfs you can change the default test
driver used for get_fs_type() by exporting it into your environment. For
example of other test defaults you can override refer to kmod.sh
allow_user_defaults().
Behind the scenes this is how we fine tune at a test case prior to
hitting a trigger to run it:
The kmod.sh script uses the above constructs to build different test cases.
A bit of interpretation of the current failures follows, first two
premises:
a) When request_module() is used userspace figures out an optimized
version of module order for us. Once it finds the modules it needs, as
per depmod symbol dep map, it will finit_module() the respective
modules which are needed for the original request_module() request.
b) We have an optimization in place whereby if a kernel uses
request_module() on a module already loaded we never bother userspace
as the module already is loaded. This is all handled by kernel/kmod.c.
A few things to consider to help identify root causes of issues:
0) kmod 19 has a broken heuristic for modules being assumed to be
built-in to your kernel and will return 0 even though request_module()
failed. Upgrade to a newer version of kmod.
1) A get_fs_type() call for "xfs" will request_module() for "fs-xfs",
not for "xfs". The optimization in kernel described in b) fails to
catch if we have a lot of consecutive get_fs_type() calls. The reason
is the optimization in place does not look for aliases. This means two
consecutive get_fs_type() calls will bump kmod_concurrent, whereas
request_module() will not.
This one explanation why test case 0009 fails at least once for
get_fs_type().
2) If a module fails to load --- for whatever reason (kmod_concurrent
limit reached, file not yet present due to rootfs switch, out of
memory) we have a period of time during which module request for the
same name either with request_module() or get_fs_type() will *also*
fail to load even if the file for the module is ready.
This explains why *multiple* NULLs are possible on test 0009.
3) finit_module() consumes quite a bit of memory.
4) Filesystems typically also have more dependent modules than other
modules, its important to note though that even though a get_fs_type()
call does not incur additional kmod_concurrent bumps, since userspace
loads dependencies it finds it needs via finit_module_fd(), it *will*
take much more memory to load a module with a lot of dependencies.
Because of 3) and 4) we will easily run into out of memory failures with
certain tests. For instance test 0006 fails on qemu with 1024 MiB of RAM.
It panics a box after reaping all userspace processes and still not
having enough memory to reap.
[arnd@arndb.de: add dependencies for test module] Link: http://lkml.kernel.org/r/20170630154834.3689272-1-arnd@arndb.de Link: http://lkml.kernel.org/r/20170628223155.26472-3-mcgrof@kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Jessica Yu <jeyu@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michal Marek <mmarek@suse.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The arch uses a verbatim copy of the asm-generic version and does not
add any own implementations to the header, so use asm-generic/fb.h
instead of duplicating code.
Link: http://lkml.kernel.org/r/20170517083545.2115-1-tklauser@distanz.ch Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Fri, 14 Jul 2017 21:49:57 +0000 (14:49 -0700)]
fault-inject: simplify access check for fail-nth
The fail-nth file is created with 0666 and the access is permitted if
and only if the task is current.
This file is owned by the currnet user. So we can create it with 0644
and allow the owner to write it. This enables to watch the status of
task->fail_nth from another processes.
Akinobu Mita [Fri, 14 Jul 2017 21:49:54 +0000 (14:49 -0700)]
fault-inject: make fail-nth read/write interface symmetric
The read interface for fail-nth looks a bit odd. Read from this file
returns "NYYYY..." or "YYYYY..." (this makes me surprise when cat this
file). Because there is no EOF condition. The first character
indicates current->fail_nth is zero or not, and then current->fail_nth
is reset to zero.
Just returning task->fail_nth value is more natural to understand.
Akinobu Mita [Fri, 14 Jul 2017 21:49:52 +0000 (14:49 -0700)]
fault-inject: parse as natural 1-based value for fail-nth write interface
The value written to fail-nth file is parsed as 0-based. Parsing as
one-based is more natural to understand and it enables to cancel the
previous setup by simply writing '0'.
This change also converts task->fail_nth from signed to unsigned int.
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