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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / Hibernate: Drop the check of swap space size for compressed image
PM / shmobile: fix A3SP suspend method
PM / Domains: Skip governor functions for CONFIG_PM_RUNTIME unset
PM / Domains: Fix build for CONFIG_PM_SLEEP unset
PM: Make sysrq-o be available for CONFIG_PM unset
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For compressed image, the space required is not known until
we finish compressing and writing all pages.
This patch drops the check, and if swap space is not enough
finally, system can still restore to normal after writing
swap fails for compressed images.
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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After commit 1eb208aea3179dd2fc0cdeea45ef869d75b4fe70, "PM: Make
CONFIG_PM depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME)", the
files under kernel/power are not built unless CONFIG_PM_SLEEP or
CONFIG_PM_RUNTIME is set. In particular, this causes
kernel/power/poweroff.c to be omitted, even though it should be
compiled, because CONFIG_MAGIC_SYSRQ is set.
Fix the problem by causing kernel/power/Makefile to be processed
for CONFIG_PM unset too.
Reported-and-tested-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
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Recent changes to kernel/module.c caused the following compile
error:
kernel/module.c: In function ‘show_taint’:
kernel/module.c:1024:2: error: implicit declaration of function ‘module_flags_taint’ [-Werror=implicit-function-declaration]
cc1: some warnings being treated as errors
Correct this error by moving the definition of module_flags_taint
outside of the #ifdef CONFIG_MODULE_UNLOAD section.
Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* 'for-3.3/core' of git://git.kernel.dk/linux-block: (37 commits)
Revert "block: recursive merge requests"
block: Stop using macro stubs for the bio data integrity calls
blockdev: convert some macros to static inlines
fs: remove unneeded plug in mpage_readpages()
block: Add BLKROTATIONAL ioctl
block: Introduce blk_set_stacking_limits function
block: remove WARN_ON_ONCE() in exit_io_context()
block: an exiting task should be allowed to create io_context
block: ioc_cgroup_changed() needs to be exported
block: recursive merge requests
block, cfq: fix empty queue crash caused by request merge
block, cfq: move icq creation and rq->elv.icq association to block core
block, cfq: restructure io_cq creation path for io_context interface cleanup
block, cfq: move io_cq exit/release to blk-ioc.c
block, cfq: move icq cache management to block core
block, cfq: move io_cq lookup to blk-ioc.c
block, cfq: move cfqd->icq_list to request_queue and add request->elv.icq
block, cfq: reorganize cfq_io_context into generic and cfq specific parts
block: remove elevator_queue->ops
block: reorder elevator switch sequence
...
Fix up conflicts in:
- block/blk-cgroup.c
Switch from can_attach_task to can_attach
- block/cfq-iosched.c
conflict with now removed cic index changes (we now use q->id instead)
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cic is association between io_context and request_queue. A cic is
linked from both ioc and q and should be destroyed when either one
goes away. As ioc and q both have their own locks, locking becomes a
bit complex - both orders work for removal from one but not from the
other.
Currently, cfq tries to circumvent this locking order issue with RCU.
ioc->lock nests inside queue_lock but the radix tree and cic's are
also protected by RCU allowing either side to walk their lists without
grabbing lock.
This rather unconventional use of RCU quickly devolves into extremely
fragile convolution. e.g. The following is from cfqd going away too
soon after ioc and q exits raced.
general protection fault: 0000 [#1] PREEMPT SMP
CPU 2
Modules linked in:
[ 88.503444]
Pid: 599, comm: hexdump Not tainted 3.1.0-rc10-work+ #158 Bochs Bochs
RIP: 0010:[<ffffffff81397628>] [<ffffffff81397628>] cfq_exit_single_io_context+0x58/0xf0
...
Call Trace:
[<ffffffff81395a4a>] call_for_each_cic+0x5a/0x90
[<ffffffff81395ab5>] cfq_exit_io_context+0x15/0x20
[<ffffffff81389130>] exit_io_context+0x100/0x140
[<ffffffff81098a29>] do_exit+0x579/0x850
[<ffffffff81098d5b>] do_group_exit+0x5b/0xd0
[<ffffffff81098de7>] sys_exit_group+0x17/0x20
[<ffffffff81b02f2b>] system_call_fastpath+0x16/0x1b
The only real hot path here is cic lookup during request
initialization and avoiding extra locking requires very confined use
of RCU. This patch makes cic removal from both ioc and request_queue
perform double-locking and unlink immediately.
* From q side, the change is almost trivial as ioc->lock nests inside
queue_lock. It just needs to grab each ioc->lock as it walks
cic_list and unlink it.
* From ioc side, it's a bit more difficult because of inversed lock
order. ioc needs its lock to walk its cic_list but can't grab the
matching queue_lock and needs to perform unlock-relock dancing.
Unlinking is now wholly done from put_io_context() and fast path is
optimized by using the queue_lock the caller already holds, which is
by far the most common case. If the ioc accessed multiple devices,
it tries with trylock. In unlikely cases of fast path failure, it
falls back to full double-locking dance from workqueue.
Double-locking isn't the prettiest thing in the world but it's *far*
simpler and more understandable than RCU trick without adding any
meaningful overhead.
This still leaves a lot of now unnecessary RCU logics. Future patches
will trim them.
-v2: Vivek pointed out that cic->q was being dereferenced after
cic->release() was called. Updated to use local variable @this_q
instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Ignoring copy_io() during fork, io_context can be allocated from two
places - current_io_context() and set_task_ioprio(). The former is
always called from local task while the latter can be called from
different task. The synchornization between them are peculiar and
dubious.
* current_io_context() doesn't grab task_lock() and assumes that if it
saw %NULL ->io_context, it would stay that way until allocation and
assignment is complete. It has smp_wmb() between alloc/init and
assignment.
* set_task_ioprio() grabs task_lock() for assignment and does
smp_read_barrier_depends() between "ioc = task->io_context" and "if
(ioc)". Unfortunately, this doesn't achieve anything - the latter
is not a dependent load of the former. ie, if ioc itself were being
dereferenced "ioc->xxx", it would mean something (not sure what tho)
but as the code currently stands, the dependent read barrier is
noop.
As only one of the the two test-assignment sequences is task_lock()
protected, the task_lock() can't do much about race between the two.
Nothing prevents current_io_context() and set_task_ioprio() allocating
its own ioc for the same task and overwriting the other's.
Also, set_task_ioprio() can race with exiting task and create a new
ioc after exit_io_context() is finished.
ioc get/put doesn't have any reason to be complex. The only hot path
is accessing the existing ioc of %current, which is simple to achieve
given that ->io_context is never destroyed as long as the task is
alive. All other paths can happily go through task_lock() like all
other task sub structures without impacting anything.
This patch updates ioc get/put so that it becomes more conventional.
* alloc_io_context() is replaced with get_task_io_context(). This is
the only interface which can acquire access to ioc of another task.
On return, the caller has an explicit reference to the object which
should be put using put_io_context() afterwards.
* The functionality of current_io_context() remains the same but when
creating a new ioc, it shares the code path with
get_task_io_context() and always goes through task_lock().
* get_io_context() now means incrementing ref on an ioc which the
caller already has access to (be that an explicit refcnt or implicit
%current one).
* PF_EXITING inhibits creation of new io_context and once
exit_io_context() is finished, it's guaranteed that both ioc
acquisition functions return %NULL.
* All users are updated. Most are trivial but
smp_read_barrier_depends() removal from cfq_get_io_context() needs a
bit of explanation. I suppose the original intention was to ensure
ioc->ioprio is visible when set_task_ioprio() allocates new
io_context and installs it; however, this wouldn't have worked
because set_task_ioprio() doesn't have wmb between init and install.
There are other problems with this which will be fixed in another
patch.
* While at it, use NUMA_NO_NODE instead of -1 for wildcard node
specification.
-v2: Vivek spotted contamination from debug patch. Removed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
perf tools: Fix compile error on x86_64 Ubuntu
perf report: Fix --stdio output alignment when --showcpuutilization used
perf annotate: Get rid of field_sep check
perf annotate: Fix usage string
perf kmem: Fix a memory leak
perf kmem: Add missing closedir() calls
perf top: Add error message for EMFILE
perf test: Change type of '-v' option to INCR
perf script: Add missing closedir() calls
tracing: Fix compile error when static ftrace is enabled
recordmcount: Fix handling of elf64 big-endian objects.
perf tools: Add const.h to MANIFEST to make perf-tar-src-pkg work again
perf tools: Add support for guest/host-only profiling
perf kvm: Do guest-only counting by default
perf top: Don't update total_period on process_sample
perf hists: Stop using 'self' for struct hist_entry
perf hists: Rename total_session to total_period
x86: Add counter when debug stack is used with interrupts enabled
x86: Allow NMIs to hit breakpoints in i386
x86: Keep current stack in NMI breakpoints
...
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core
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There are four places where new filter for a given filter string is
created, which involves several different steps. This patch factors
those steps into create_[system_]filter() functions which in turn make
use of create_filter_{start|finish}() for common parts.
The only functional change is that if replace_filter_string() is
requested and fails, creation fails without any side effect instead of
being ignored.
Note that system filter is now installed after the processing is
complete which makes freeing before and then restoring filter string
on error unncessary.
-v2: Rebased to resolve conflict with 49aa29513e and updated both
create_filter() functions to always set *filterp instead of
requiring the caller to clear it to %NULL on entry.
Link: http://lkml.kernel.org/r/1323988305-1469-2-git-send-email-tj@kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Add stacktrace_filter= to the kernel command line that lets
the user pick specific functions to check the stack on.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Change set_ftrace_early_filter() to ftrace_set_early_filter()
and make it a global function. This will allow other subsystems
in the kernel to be able to enable function tracing at start
up and reuse the ftrace function parsing code.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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The stack_tracer is used to look at every function and check
if the current stack is bigger than the last recorded max stack size.
When a new max is found, then it saves that stack off.
Currently the stack tracer is limited by the global_ops of
the function tracer. As the stack tracer has nothing to do with
the ftrace function tracer, except that it uses it as its internal
engine, the stack tracer should have its own list.
A new file is added to the tracing debugfs directory called:
stack_trace_filter
that can be used to select which functions you want to check the stack
on.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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The set_ftrace_filter shows "hashed" functions, which are functions
that are added with operations to them (like traceon and traceoff).
As other subsystems may be able to show what functions they are
using for function tracing, the hash items should no longer
be shown just because the FILTER flag is set. As they have nothing
to do with other subsystems filters.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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The function tracer is set up to allow any other subsystem (like perf)
to use it. Ftrace already has a way to list what functions are enabled
by the global_ops. It would be very helpful to let other users of
the function tracer to be able to use the same code.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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There are two types of hashes in the ftrace_ops; one type
is the filter_hash and the other is the notrace_hash. Either
one may be null, meaning it has no elements. But when elements
are added, the hash is allocated.
Throughout the code, a check needs to be made to see if a hash
exists or the hash has elements, but the check if the hash exists
is usually missing causing the possible "NULL pointer dereference bug".
Add a helper routine called "ftrace_hash_empty()" that returns
true if the hash doesn't exist or its count is zero. As they mean
the same thing.
Last-bug-reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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When disabling the "notrace" records, that means we want to trace them.
If the notrace_hash is zero, it means that we want to trace all
records. But to disable a zero notrace_hash means nothing.
The check for the notrace_hash count was incorrect with:
if (hash && !hash->count)
return
With the correct comment above it that states that we do nothing
if the notrace_hash has zero count. But !hash also means that
the notrace hash has zero count. I think this was done to
protect against dereferencing NULL. But if !hash is true, then
we go through the following loop without doing a single thing.
Fix it to:
if (!hash || !hash->count)
return;
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Now that each set of pages in the function list are sorted by
ip, we can use bsearch to find a record within each set of pages.
This speeds up the ftrace_location() function by magnitudes.
For archs (like x86) that need to add a breakpoint at every function
that will be converted from a nop to a callback and vice versa,
the breakpoint callback needs to know if the breakpoint was for
ftrace or not. It requires finding the breakpoint ip within the
records. Doing a linear search is extremely inefficient. It is
a must to be able to do a fast binary search to find these locations.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Sort records by ip locations of the ftrace mcount calls on each of the
set of pages in the function list. This helps in localizing cache
usuage when updating the function locations, as well as gives us
the ability to quickly find an ip location in the list.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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As new functions come in to be initalized from mcount to nop,
they are done by groups of pages. Whether it is the core kernel
or a module. There's no need to keep track of these on a per record
basis.
At startup, and as any module is loaded, the functions to be
traced are stored in a group of pages and added to the function
list at the end. We just need to keep a pointer to the first
page of the list that was added, and use that to know where to
start on the list for initializing functions.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Allocate the mcount record pages as a group of pages as big
as can be allocated and waste no more than a single page.
Grouping the mcount pages as much as possible helps with cache
locality, as we do not need to redirect with descriptors as we
cross from page to page. It also allows us to do more with the
records later on (sort them with bigger benefits).
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Records that are added to the function trace table are
permanently there, except for modules. By separating out the
modules to their own pages that can be freed in one shot
we can remove the "freed" flag and simplify some of the record
management.
Another benefit of doing this is that we can also move the
records around; sort them.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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The stop machine method to modify all functions in the kernel
(some 20,000 of them) is the safest way to do so across all archs.
But some archs may not need this big hammer approach to modify code
on SMP machines, and can simply just update the code it needs.
Adding a weak function arch_ftrace_update_code() that now does the
stop machine, will also let any arch override this method.
If the arch needs to check the system and then decide if it can
avoid stop machine, it can still call ftrace_run_stop_machine() to
use the old method.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Multiple users of the function tracer can register their functions
with the ftrace_ops structure. The accounting within ftrace will
update the counter on each function record that is being traced.
When the ftrace_ops filtering adds or removes functions, the
function records will be updated accordingly if the ftrace_ops is
still registered.
When a ftrace_ops is removed, the counter of the function records,
that the ftrace_ops traces, are decremented. When they reach zero
the functions that they represent are modified to stop calling the
mcount code.
When changes are made, the code is updated via stop_machine() with
a command passed to the function to tell it what to do. There is an
ENABLE and DISABLE command that tells the called function to enable
or disable the functions. But the ENABLE is really a misnomer as it
should just update the records, as records that have been enabled
and now have a count of zero should be disabled.
The DISABLE command is used to disable all functions regardless of
their counter values. This is the big off switch and is not the
complement of the ENABLE command.
To make matters worse, when a ftrace_ops is unregistered and there
is another ftrace_ops registered, neither the DISABLE nor the
ENABLE command are set when calling into the stop_machine() function
and the records will not be updated to match their counter. A command
is passed to that function that will update the mcount code to call
the registered callback directly if it is the only one left. This
means that the ftrace_ops that is still registered will have its callback
called by all functions that have been set for it as well as the ftrace_ops
that was just unregistered.
Here's a way to trigger this bug. Compile the kernel with
CONFIG_FUNCTION_PROFILER set and with CONFIG_FUNCTION_GRAPH not set:
CONFIG_FUNCTION_PROFILER=y
# CONFIG_FUNCTION_GRAPH is not set
This will force the function profiler to use the function tracer instead
of the function graph tracer.
# cd /sys/kernel/debug/tracing
# echo schedule > set_ftrace_filter
# echo function > current_tracer
# cat set_ftrace_filter
schedule
# cat trace
# tracer: nop
#
# entries-in-buffer/entries-written: 692/68108025 #P:4
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
kworker/0:2-909 [000] .... 531.235574: schedule <-worker_thread
<idle>-0 [001] .N.. 531.235575: schedule <-cpu_idle
kworker/0:2-909 [000] .... 531.235597: schedule <-worker_thread
sshd-2563 [001] .... 531.235647: schedule <-schedule_hrtimeout_range_clock
# echo 1 > function_profile_enabled
# echo 0 > function_porfile_enabled
# cat set_ftrace_filter
schedule
# cat trace
# tracer: function
#
# entries-in-buffer/entries-written: 159701/118821262 #P:4
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
<idle>-0 [002] ...1 604.870655: local_touch_nmi <-cpu_idle
<idle>-0 [002] d..1 604.870655: enter_idle <-cpu_idle
<idle>-0 [002] d..1 604.870656: atomic_notifier_call_chain <-enter_idle
<idle>-0 [002] d..1 604.870656: __atomic_notifier_call_chain <-atomic_notifier_call_chain
The same problem could have happened with the trace_probe_ops,
but they are modified with the set_frace_filter file which does the
update at closure of the file.
The simple solution is to change ENABLE to UPDATE and call it every
time an ftrace_ops is unregistered.
Link: http://lkml.kernel.org/r/1323105776-26961-3-git-send-email-jolsa@redhat.com
Cc: stable@vger.kernel.org # 3.0+
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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* 'for-linus' of git://selinuxproject.org/~jmorris/linux-security:
capabilities: remove __cap_full_set definition
security: remove the security_netlink_recv hook as it is equivalent to capable()
ptrace: do not audit capability check when outputing /proc/pid/stat
capabilities: remove task_ns_* functions
capabitlies: ns_capable can use the cap helpers rather than lsm call
capabilities: style only - move capable below ns_capable
capabilites: introduce new has_ns_capabilities_noaudit
capabilities: call has_ns_capability from has_capability
capabilities: remove all _real_ interfaces
capabilities: introduce security_capable_noaudit
capabilities: reverse arguments to security_capable
capabilities: remove the task from capable LSM hook entirely
selinux: sparse fix: fix several warnings in the security server cod
selinux: sparse fix: fix warnings in netlink code
selinux: sparse fix: eliminate warnings for selinuxfs
selinux: sparse fix: declare selinux_disable() in security.h
selinux: sparse fix: move selinux_complete_init
selinux: sparse fix: make selinux_secmark_refcount static
SELinux: Fix RCU deref check warning in sel_netport_insert()
Manually fix up a semantic mis-merge wrt security_netlink_recv():
- the interface was removed in commit fd7784615248 ("security: remove
the security_netlink_recv hook as it is equivalent to capable()")
- a new user of it appeared in commit a38f7907b926 ("crypto: Add
userspace configuration API")
causing no automatic merge conflict, but Eric Paris pointed out the
issue.
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Once upon a time netlink was not sync and we had to get the effective
capabilities from the skb that was being received. Today we instead get
the capabilities from the current task. This has rendered the entire
purpose of the hook moot as it is now functionally equivalent to the
capable() call.
Signed-off-by: Eric Paris <eparis@redhat.com>
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Reading /proc/pid/stat of another process checks if one has ptrace permissions
on that process. If one does have permissions it outputs some data about the
process which might have security and attack implications. If the current
task does not have ptrace permissions the read still works, but those fields
are filled with inocuous (0) values. Since this check and a subsequent denial
is not a violation of the security policy we should not audit such denials.
This can be quite useful to removing ptrace broadly across a system without
flooding the logs when ps is run or something which harmlessly walks proc.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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task_ in the front of a function, in the security subsystem anyway, means
to me at least, that we are operating with that task as the subject of the
security decision. In this case what it means is that we are using current as
the subject but we use the task to get the right namespace. Who in the world
would ever realize that's what task_ns_capability means just by the name? This
patch eliminates the task_ns functions entirely and uses the has_ns_capability
function instead. This means we explicitly open code the ns in question in
the caller. I think it makes the caller a LOT more clear what is going on.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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Just to reduce the number of places to change if we every change the LSM
hook, use the capability helpers internally when possible.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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Although the current code is fine for consistency this moves the capable
code below the function it calls in the c file. It doesn't actually change
code.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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For consistency in interfaces, introduce a new interface called
has_ns_capabilities_noaudit. It checks if the given task has the given
capability in the given namespace. Use this new function by
has_capabilities_noaudit.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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Declare the more specific has_ns_capability first in the code and then call it
from has_capability. The declaration reversal isn't stricty necessary since
they are both declared in header files, but it just makes sense to put more
specific functions first in the code.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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The name security_real_capable and security_real_capable_noaudit just don't
make much sense to me. Convert them to use security_capable and
security_capable_noaudit.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
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security_capable takes ns, cred, cap. But the LSM capable() hook takes
cred, ns, cap. The capability helper functions also take cred, ns, cap.
Rather than flip argument order just to flip it back, leave them alone.
Heck, this should be a little faster since argument will be in the right
place!
Signed-off-by: Eric Paris <eparis@redhat.com>
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Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1
* tag 'for-linus' of git://github.com/rustyrussell/linux:
module_param: check that bool parameters really are bool.
intelfbdrv.c: bailearly is an int module_param
paride/pcd: fix bool verbose module parameter.
module_param: make bool parameters really bool (drivers & misc)
module_param: make bool parameters really bool (arch)
module_param: make bool parameters really bool (core code)
kernel/async: remove redundant declaration.
printk: fix unnecessary module_param_name.
lirc_parallel: fix module parameter description.
module_param: avoid bool abuse, add bint for special cases.
module_param: check type correctness for module_param_array
modpost: use linker section to generate table.
modpost: use a table rather than a giant if/else statement.
modules: sysfs - export: taint, coresize, initsize
kernel/params: replace DEBUGP with pr_debug
module: replace DEBUGP with pr_debug
module: struct module_ref should contains long fields
module: Fix performance regression on modules with large symbol tables
module: Add comments describing how the "strmap" logic works
Fix up conflicts in scripts/mod/file2alias.c due to the new linker-
generated table approach to adding __mod_*_device_table entries. The
ARM sa11x0 mcp bus needed to be converted to that too.
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module_param(bool) used to counter-intuitively take an int. In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.
It's time to remove the int/unsigned int option. For this version
it'll simply give a warning, but it'll break next kernel version.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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It's in linux/init.h, and I'm about to change it to a bool.
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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You don't need module_param_name if the name is the same!
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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For historical reasons, we allow module_param(bool) to take an int (or
an unsigned int). That's going away.
A few drivers really want an int: they set it to -1 and a parameter
will set it to 0 or 1. This sucks: reading them from sysfs will give
'Y' for both -1 and 1, but if we change it to an int, then the users
might be broken (if they did "param" instead of "param=1").
Use a new 'bint' parser for them.
(ntfs has a different problem: it needs an int for debug_msgs because
it's also exposed via sysctl.)
Cc: Steve Glendinning <steve.glendinning@smsc.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Cc: Christoph Raisch <raisch@de.ibm.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: linux390@de.ibm.com
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: lm-sensors@lm-sensors.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: alsa-devel@alsa-project.org
Acked-by: Takashi Iwai <tiwai@suse.de> (For the sound part)
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> (For the hwmon driver)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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Recent tools do not want to use /proc to retrieve module information. A few
values are currently missing from sysfs to replace the information available
in /proc/modules.
This adds /sys/module/*/{coresize,initsize,taint} attributes.
TAINT_PROPRIETARY_MODULE (P) and TAINT_OOT_MODULE (O) flags are both always
shown now, and do no longer exclude each other, also in /proc/modules.
Replace the open-coded sysfs attribute initializers with the __ATTR() macro.
Add the new attributes to Documentation/ABI.
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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Use more flexible pr_debug. This allows:
echo "module params +p" > /dbg/dynamic_debug/control
to turn on debug messages when needed.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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Use more flexible pr_debug. This allows:
echo "module module +p" > /dbg/dynamic_debug/control
to turn on debug messages when needed.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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module_ref contains two "unsigned int" fields.
Thats now too small, since some machines can open more than 2^32 files.
Check commit 518de9b39e8 (fs: allow for more than 2^31 files) for
reference.
We can add an aligned(2 * sizeof(unsigned long)) attribute to force
alloc_percpu() allocating module_ref areas in single cache lines.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Tejun Heo <tj@kernel.org>
CC: Robin Holt <holt@sgi.com>
CC: David Miller <davem@davemloft.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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Looking at /proc/kallsyms, one starts to ponder whether all of the extra
strtab-related complexity in module.c is worth the memory savings.
Instead of making the add_kallsyms() loop even more complex, I tried the
other route of deleting the strmap logic and naively copying each string
into core_strtab with no consideration for consolidating duplicates.
Performance on an "already exists" insmod of nvidia.ko (runs
add_kallsyms() but does not actually initialize the module):
Original scheme: 1.230s
With naive copying: 0.058s
Extra space used: 35k (of a 408k module).
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <73defb5e4bca04a6431392cc341112b1@localhost>
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Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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When we restore a task we need to set up text, data and data heap sizes
from userspace to the values a task had at checkpoint time. This patch
adds auxilary prctl codes for that.
While most of them have a statistical nature (their values are involved
into calculation of /proc/<pid>/statm output) the start_brk and brk values
are used to compute an allowed size of program data segment expansion.
Which means an arbitrary changes of this values might be dangerous
operation. So to restrict access the following requirements applied to
prctl calls:
- The process has to have CAP_SYS_ADMIN capability granted.
- For all opcodes except start_brk/brk members an appropriate
VMA area must exist and should fit certain VMA flags,
such as:
- code segment must be executable but not writable;
- data segment must not be executable.
start_brk/brk values must not intersect with data segment and must not
exceed RLIMIT_DATA resource limit.
Still the main guard is CAP_SYS_ADMIN capability check.
Note the kernel should be compiled with CONFIG_CHECKPOINT_RESTORE support
otherwise these prctl calls will return -EINVAL.
[akpm@linux-foundation.org: cache current->mm in a local, saving 200 bytes text]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When an oops causes a panic and panic prints another backtrace it's pretty
common to have the original oops data be scrolled away on a 80x50 screen.
The second backtrace is quite redundant and not needed anyways.
So don't print the panic backtrace when oops_in_progress is true.
[akpm@linux-foundation.org: add comment]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The sysctl works on the current task's pid namespace, getting and setting
its last_pid field.
Writing is allowed for CAP_SYS_ADMIN-capable tasks thus making it possible
to create a task with desired pid value. This ability is required badly
for the checkpoint/restore in userspace.
This approach suits all the parties for now.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When two CPUs call panic at the same time there is a possible race
condition that can stop kdump. The first CPU calls crash_kexec() and the
second CPU calls smp_send_stop() in panic() before crash_kexec() finished
on the first CPU. So the second CPU stops the first CPU and therefore
kdump fails:
1st CPU:
panic()->crash_kexec()->mutex_trylock(&kexec_mutex)-> do kdump
2nd CPU:
panic()->crash_kexec()->kexec_mutex already held by 1st CPU
->smp_send_stop()-> stop 1st CPU (stop kdump)
This patch fixes the problem by introducing a spinlock in panic that
allows only one CPU to process crash_kexec() and the subsequent panic
code.
All other CPUs call the weak function panic_smp_self_stop() that stops the
CPU itself. This function can be overloaded by architecture code. For
example "tile" can use their lower-power "nap" instruction for that.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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