31 Oct, 2011
2 commits
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There are files which use module_param and MODULE_PARM_DESC
back to back. They only include moduleparam.h which makes sense,
but the implicit presence of module.h everywhere hid the fact
that MODULE_PARM_DESC wasn't in moduleparam.h at all. Relocate
the macro to moduleparam.h so that the moduleparam infrastructure
can be used independently of module.hSigned-off-by: Paul Gortmaker
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A lot of files pull in module.h when all they are really
looking for is the basic EXPORT_SYMBOL functionality. The
recent data from Ingo[1] shows that this is one of several
instances that has a significant impact on compile times,
and it should be targeted for factoring out (as done here).Note that several commonly used header files in include/*
directly include themselves (some 34 of them!)
The most commonly used ones of these will have to be made
independent of module.h before the full benefit of this change
can be realized.We also transition THIS_MODULE from module.h to export.h,
since there are lots of files with subsystem structs that
in turn will have a struct module *owner and only be doing:.owner = THIS_MODULE;
and absolutely nothing else modular. So, we also want to have
the THIS_MODULE definition present in the lightweight header.[1] https://lkml.org/lkml/2011/5/23/76
Signed-off-by: Paul Gortmaker
11 Aug, 2011
1 commit
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Copy the information needed from struct module into a local module list
held within tracepoint.c from within the module coming/going notifier.This vastly simplifies locking of tracepoint registration /
unregistration, because we don't have to take the module mutex to
register and unregister tracepoints anymore. Steven Rostedt ran into
dependency problems related to modules mutex vs kprobes mutex vs ftrace
mutex vs tracepoint mutex that seems to be hard to fix without removing
this dependency between tracepoint and module mutex. (note: it should be
investigated whether kprobes could benefit of being dissociated from the
modules mutex too.)This also fixes module handling of tracepoint list iterators, because it
was expecting the list to be sorted by pointer address. Given we have
control on our own list now, it's OK to sort this list which has
tracepoints as its only purpose. The reason why this sorting is required
is to handle the fact that seq files (and any read() operation from
user-space) cannot hold the tracepoint mutex across multiple calls, so
list entries may vanish between calls. With sorting, the tracepoint
iterator becomes usable even if the list don't contain the exact item
pointed to by the iterator anymore.Signed-off-by: Mathieu Desnoyers
Acked-by: Jason Baron
CC: Ingo Molnar
CC: Lai Jiangshan
CC: Peter Zijlstra
CC: Thomas Gleixner
CC: Masami Hiramatsu
Link: http://lkml.kernel.org/r/20110810191839.GC8525@Krystal
Signed-off-by: Steven Rostedt
24 Jul, 2011
2 commits
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Userspace wants to manage module parameters with udev rules.
This currently only works for loaded modules, but not for
built-in ones.To allow access to the built-in modules we need to
re-trigger all module load events that happened before any
userspace was running. We already do the same thing for all
devices, subsystems(buses) and drivers.This adds the currently missing /sys/module//uevent files
to all module entries.Signed-off-by: Kay Sievers
Signed-off-by: Rusty Russell (split & trivial fix) -
This simplifies the next patch, where we have an attribute on a
builtin module (ie. module == NULL).Signed-off-by: Kay Sievers
Signed-off-by: Rusty Russell (split into 2)
19 May, 2011
5 commits
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This patch places every exported symbol in its own section
(i.e. "___ksymtab+printk"). Thus the linker will use its SORT() directive
to sort and finally merge all symbol in the right and final section
(i.e. "__ksymtab").The symbol prefixed archs use an underscore as prefix for symbols.
To avoid collision we use a different character to create the temporary
section names.This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: Alessio Igor Bogani
Signed-off-by: Rusty Russell (folded in '+' fixup)
Tested-by: Dirk Behme -
Instead of having a callback function for each symbol in the kernel,
have a callback for each array of symbols.This eases the logic when we move to sorted symbols and binary search.
Signed-off-by: Rusty Russell
Signed-off-by: Alessio Igor Bogani -
Reorder struct module to remove 24 bytes of alignment padding on 64 bit
builds when the CONFIG_TRACE options are selected. This allows the
structure to fit into one fewer cache lines, and its size drops from 592
to 568 on x86_64.Signed-off-by: Richard Kennedy
Signed-off-by: Rusty Russell -
Doing so prevents the following warning from sparse:
CHECK kernel/params.c
kernel/params.c:817:9: warning: symbol '__modver_version_show' was not
declared. Should it be static?since kernel/params.c is never compiled with MODULE being set.
Signed-off-by: Dmitry Torokhov
Signed-off-by: Rusty Russell -
On m68k natural alignment is 2-byte boundary but we are trying to
align structures in __modver section on sizeof(void *) boundary.
This causes trouble when we try to access elements in this section
in array-like fashion when create "version" attributes for built-in
modules.Moreover, as DaveM said, we can't reliably put structures into
independent objects, put them into a special section, and then expect
array access over them (via the section boundaries) after linking the
objects together to just "work" due to variable alignment choices in
different situations. The only solution that seems to work reliably
is to make an array of plain pointers to the objects in question and
put those pointers in the special section.Reported-by: Geert Uytterhoeven
Signed-off-by: Dmitry Torokhov
Signed-off-by: Rusty Russell
22 Feb, 2011
1 commit
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We force particular alignment when we generate attribute structures
when generation MODULE_VERSION() data and we need to make sure that
this alignment is followed when we iterate over these structures,
otherwise we may crash on platforms whose natural alignment is not
sizeof(void *), such as m68k.Reported-by: Geert Uytterhoeven
Signed-off-by: Dmitry Torokhov
[ There are more issues here, but the fixes are incredibly ugly - Linus ]
Signed-off-by: Linus Torvalds
03 Feb, 2011
2 commits
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Make the tracepoints more robust, making them solid enough to handle compiler
changes by not relying on anything based on compiler-specific behavior with
respect to structure alignment. Implement an approach proposed by David Miller:
use an array of const pointers to refer to the individual structures, and export
this pointer array through the linker script rather than the structures per se.
It will consume 32 extra bytes per tracepoint (24 for structure padding and 8
for the pointers), but are less likely to break due to compiler changes.History:
commit 7e066fb8 tracepoints: add DECLARE_TRACE() and DEFINE_TRACE()
added the aligned(32) type and variable attribute to the tracepoint structures
to deal with gcc happily aligning statically defined structures on 32-byte
multiples.One attempt was to use a 8-byte alignment for tracepoint structures by applying
both the variable and type attribute to tracepoint structures definitions and
declarations. It worked fine with gcc 4.5.1, but broke with gcc 4.4.4 and 4.4.5.The reason is that the "aligned" attribute only specify the _minimum_ alignment
for a structure, leaving both the compiler and the linker free to align on
larger multiples. Because tracepoint.c expects the structures to be placed as an
array within each section, up-alignment cause NULL-pointer exceptions due to the
extra unexpected padding.(this patch applies on top of -tip)
Signed-off-by: Mathieu Desnoyers
Acked-by: David S. Miller
LKML-Reference:
CC: Frederic Weisbecker
CC: Ingo Molnar
CC: Thomas Gleixner
CC: Andrew Morton
CC: Peter Zijlstra
CC: Rusty Russell
Signed-off-by: Steven Rostedt -
Currently the trace_event structures are placed in the _ftrace_events
section, and at link time, the linker makes one large array of all
the trace_event structures. On boot up, this array is read (much like
the initcall sections) and the events are processed.The problem is that there is no guarantee that gcc will place complex
structures nicely together in an array format. Two structures in the
same file may be placed awkwardly, because gcc has no clue that they
are suppose to be in an array.A hack was used previous to force the alignment to 4, to pack the
structures together. But this caused alignment issues with other
architectures (sparc).Instead of packing the structures into an array, the structures' addresses
are now put into the _ftrace_event section. As pointers are always the
natural alignment, gcc should always pack them tightly together
(otherwise initcall, extable, etc would also fail).By having the pointers to the structures in the section, we can still
iterate the trace_events without causing unnecessary alignment problems
with other architectures, or depending on the current behaviour of
gcc that will likely change in the future just to tick us kernel developers
off a little more.The _ftrace_event section is also moved into the .init.data section
as it is now only needed at boot up.Suggested-by: David Miller
Cc: Mathieu Desnoyers
Acked-by: David S. Miller
Signed-off-by: Steven Rostedt
24 Jan, 2011
2 commits
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lib/built-in.o:(__modver+0x8): undefined reference to `__modver_version_show'
lib/built-in.o:(__modver+0x2c): undefined reference to `__modver_version_show'Simplest to just not emit anything: if they've disabled SYSFS they probably
want the smallest kernel possible.Reported-by: Randy Dunlap
Signed-off-by: Rusty Russell -
Currently only drivers that are built as modules have their versions
shown in /sys/module//version, but this information might
also be useful for built-in drivers as well. This especially important
for drivers that do not define any parameters - such drivers, if
built-in, are completely invisible from userspace.This patch changes MODULE_VERSION() macro so that in case when we are
compiling built-in module, version information is stored in a separate
section. Kernel then uses this data to create 'version' sysfs attribute
in the same fashion it creates attributes for module parameters.Signed-off-by: Dmitry Torokhov
Signed-off-by: Rusty Russell
23 Dec, 2010
1 commit
24 Nov, 2010
1 commit
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Commit 9bea7f23952d5948f8e5dfdff4de09bb9981fb5f renamed use_module to
ref_module (and changed its return value), but forgot to update this
prototype in module.h.Signed-off-by: Anders Kaseorg
Acked-by: WANG Cong
Signed-off-by: Rusty Russell
18 Nov, 2010
1 commit
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This patch is a logical extension of the protection provided by
CONFIG_DEBUG_RODATA to LKMs. The protection is provided by
splitting module_core and module_init into three logical parts
each and setting appropriate page access permissions for each
individual section:1. Code: RO+X
2. RO data: RO+NX
3. RW data: RW+NXIn order to achieve proper protection, layout_sections() have
been modified to align each of the three parts mentioned above
onto page boundary. Next, the corresponding page access
permissions are set right before successful exit from
load_module(). Further, free_module() and sys_init_module have
been modified to set module_core and module_init as RW+NX right
before calling module_free().By default, the original section layout and access flags are
preserved. When compiled with CONFIG_DEBUG_SET_MODULE_RONX=y,
the patch will page-align each group of sections to ensure that
each page contains only one type of content and will enforce
RO/NX for each group of pages.-v1: Initial proof-of-concept patch.
-v2: The patch have been re-written to reduce the number of #ifdefs
and to make it architecture-agnostic. Code formatting has also
been corrected.
-v3: Opportunistic RO/NX protection is now unconditional. Section
page-alignment is enabled when CONFIG_DEBUG_RODATA=y.
-v4: Removed most macros and improved coding style.
-v5: Changed page-alignment and RO/NX section size calculation
-v6: Fixed comments. Restricted RO/NX enforcement to x86 only
-v7: Introduced CONFIG_DEBUG_SET_MODULE_RONX, added
calls to set_all_modules_text_rw() and set_all_modules_text_ro()
in ftrace
-v8: updated for compatibility with linux 2.6.33-rc5
-v9: coding style fixes
-v10: more coding style fixes
-v11: minor adjustments for -tip
-v12: minor adjustments for v2.6.35-rc2-tip
-v13: minor adjustments for v2.6.37-rc1-tipSigned-off-by: Siarhei Liakh
Signed-off-by: Xuxian Jiang
Acked-by: Arjan van de Ven
Reviewed-by: James Morris
Signed-off-by: H. Peter Anvin
Cc: Andi Kleen
Cc: Rusty Russell
Cc: Stephen Rothwell
Cc: Dave Jones
Cc: Kees Cook
Cc: Linus Torvalds
LKML-Reference:
[ minor cleanliness edits, -v14: build failure fix ]
Signed-off-by: Ingo Molnar
08 Oct, 2010
1 commit
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Conflicts:
arch/x86/kernel/module.cMerge reason: Resolve the conflict, pick up fixes.
Signed-off-by: Ingo Molnar
06 Oct, 2010
1 commit
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With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible to do most of the module loading in parallel.However, that whole conversion totally missed the rather obscure code
that adds a new module to the list for BUG() handling. That code was
doubly obscure because (a) the code itself lives in lib/bugs.c (for
dubious reasons) and (b) it gets called from the architecture-specific
"module_finalize()" rather than from generic code.Calling it from arch-specific code makes no sense what-so-ever to begin
with, and is now actively wrong since that code isn't protected by the
module loading lock any more.So this commit moves the "module_bug_{finalize,cleanup}()" calls away
from the arch-specific code, and into the generic code - and in the
process protects it with the module_mutex so that the list operations
are now safe.Future fixups:
- move the module list handling code into kernel/module.c where it
belongs.
- get rid of 'module_bug_list' and just use the regular list of modules
(called 'modules' - imagine that) that we already create and maintain
for other reasons.Reported-and-tested-by: Thomas Gleixner
Cc: Rusty Russell
Cc: Adrian Bunk
Cc: Andrew Morton
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds
23 Sep, 2010
1 commit
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base patch to implement 'jump labeling'. Based on a new 'asm goto' inline
assembly gcc mechanism, we can now branch to labels from an 'asm goto'
statment. This allows us to create a 'no-op' fastpath, which can subsequently
be patched with a jump to the slowpath code. This is useful for code which
might be rarely used, but which we'd like to be able to call, if needed.
Tracepoints are the current usecase that these are being implemented for.Acked-by: David S. Miller
Signed-off-by: Jason Baron
LKML-Reference:[ cleaned up some formating ]
Signed-off-by: Steven Rostedt
05 Jun, 2010
3 commits
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These were placed in the header in ef665c1a06 to get the various
SYSFS/MODULE config combintations to compile.That may have been necessary then, but it's not now. These functions
are all local to module.c.Signed-off-by: Rusty Russell
Cc: Randy Dunlap -
Linus changed the structure, and luckily this didn't compile any more.
Reported-by: Stephen Rothwell
Signed-off-by: Rusty Russell
Cc: Jason Wessel
Cc: Martin Hicks -
When adding a module that depends on another one, we used to create a
one-way list of "modules_which_use_me", so that module unloading could
see who needs a module.It's actually quite simple to make that list go both ways: so that we
not only can see "who uses me", but also see a list of modules that are
"used by me".In fact, we always wanted that list in "module_unload_free()": when we
unload a module, we want to also release all the other modules that are
used by that module. But because we didn't have that list, we used to
first iterate over all modules, and then iterate over each "used by me"
list of that module.By making the list two-way, we simplify module_unload_free(), and it
allows for some trivial fixes later too.Signed-off-by: Linus Torvalds
Signed-off-by: Rusty Russell (cleaned & rebased)
08 Apr, 2010
1 commit
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Conflicts:
include/linux/module.h
kernel/module.cSemantic conflict:
include/trace/events/module.hMerge reason: Resolve the conflict with upstream commit 5fbfb18 ("Fix up
possibly racy module refcounting")Signed-off-by: Ingo Molnar
06 Apr, 2010
1 commit
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Module refcounting is implemented with a per-cpu counter for speed.
However there is a race when tallying the counter where a reference may
be taken by one CPU and released by another. Reference count summation
may then see the decrement without having seen the previous increment,
leading to lower than expected count. A module which never has its
actual reference drop below 1 may return a reference count of 0 due to
this race.Module removal generally runs under stop_machine, which prevents this
race causing bugs due to removal of in-use modules. However there are
other real bugs in module.c code and driver code (module_refcount is
exported) where the callers do not run under stop_machine.Fix this by maintaining running per-cpu counters for the number of
module refcount increments and the number of refcount decrements. The
increments are tallied after the decrements, so any decrement seen will
always have its corresponding increment counted. The final refcount is
the difference of the total increments and decrements, preventing a
low-refcount from being returned.Signed-off-by: Nick Piggin
Acked-by: Rusty Russell
Signed-off-by: Linus Torvalds
01 Apr, 2010
1 commit
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Remove the @refcnt argument, because it has side-effects, and arguments with
side-effects are not skipped by the jump over disabled instrumentation and are
executed even when the tracepoint is disabled.This was also causing a GPF as found by Randy Dunlap:
Subject: 2.6.33 GP fault only when built with tracing
LKML-Reference:Note, the current 2.6.34-rc has a fix for the actual cause of the GPF,
but this fixes one of its triggers.Tested-by: Randy Dunlap
Acked-by: Mathieu Desnoyers
Signed-off-by: Li Zefan
LKML-Reference:
Signed-off-by: Steven Rostedt
31 Mar, 2010
1 commit
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Fix build for CONFIG_MODULES not enabled by providing a stub
for is_module_percpu_address().kernel/lockdep.c:605: error: implicit declaration of function 'is_module_percpu_address'
Signed-off-by: Randy Dunlap
Signed-off-by: Tejun Heo
29 Mar, 2010
2 commits
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lockdep has custom code to check whether a pointer belongs to static
percpu area which is somewhat broken. Implement proper
is_kernel/module_percpu_address() and replace the custom code.On UP, percpu variables are regular static variables and can't be
distinguished from them. Always return %false on UP.Signed-off-by: Tejun Heo
Acked-by: Peter Zijlstra
Cc: Rusty Russell
Cc: Ingo Molnar -
Better encapsulate module static percpu area handling so that code
outsidef of CONFIG_SMP ifdef doesn't deal with mod->percpu directly
and add mod->percpu_size and record percpu_size in it. Both percpu
fields are compiled out on UP. While at it, mark mod->percpu w/
__percpu.This is to prepare for is_module_percpu_address().
Signed-off-by: Tejun Heo
Acked-by: Rusty Russell
13 Mar, 2010
1 commit
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Extern declarations in sysctl.c should be moved to their own header file,
and then include them in relavant .c files.Move modprobe_path extern declaration to linux/kmod.h
Move modules_disabled extern declaration to linux/module.hSigned-off-by: Dave Young
Cc: Rusty Russell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Feb, 2010
1 commit
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Add __percpu sparse annotations to core subsystems.
These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors. This patch doesn't affect normal builds.Signed-off-by: Tejun Heo
Reviewed-by: Christoph Lameter
Acked-by: Paul E. McKenney
Cc: Jens Axboe
Cc: linux-mm@kvack.org
Cc: Rusty Russell
Cc: Dipankar Sarma
Cc: Peter Zijlstra
Cc: Andrew Morton
Cc: Eric Biederman
05 Jan, 2010
2 commits
-
ringbuffer*.c are the last users of local.h.
Remove the include from modules.h and add it to ringbuffer files.
Signed-off-by: Christoph Lameter
Signed-off-by: Tejun Heo -
Use cpu ops to deal with the per cpu data instead of a local_t. Reduces memory
requirements, cache footprint and decreases cycle counts.The this_cpu_xx operations are also used for !SMP mode. Otherwise we could
not drop the use of __module_ref_addr() which would make per cpu data handling
complicated. this_cpu_xx operations have their own fallback for !SMP.V8-V9:
- Leave include asm/module.h since ringbuffer.c depends on it. Nothing else
does though. Another patch will deal with that.
- Remove spurious free.Signed-off-by: Christoph Lameter
Acked-by: Rusty Russell
Signed-off-by: Tejun Heo
15 Dec, 2009
1 commit
-
The next commit will require the use of MODULE_SYMBOL_PREFIX in
.tmp_exports-asm.S. Currently it is mixed in with C structure
definitions in "asm/module.h". Move the definition of this arch option
into Kconfig, so it can be easily accessed by any code.This also lets modpost.c use the same definition. Previously modpost
relied on a hardcoded list of architectures in mk_elfconfig.c.A build test for blackfin, one of the two MODULE_SYMBOL_PREFIX archs,
showed the generated code was unchanged. vmlinux was identical save
for build ids, and an apparently randomized suffix on a single "__key"
symbol in the kallsyms data).Signed-off-by: Alan Jenkins
Acked-by: Mike Frysinger (blackfin)
CC: Sam Ravnborg
Signed-off-by: Rusty Russell
24 Sep, 2009
3 commits
-
For the longest time now we've been using multiple MODULE_AUTHOR()
statements when a module has more than one author, but the comment here
disagrees.Signed-off-by: Johannes Berg
Cc: Jiri Kosina
Cc: Luciano Coelho
Signed-off-by: Andrew Morton
Signed-off-by: Rusty Russell -
Also remove all parts of the string table (referenced by the symbol
table) that are not needed for kallsyms use (i.e. which were only
referenced by symbols discarded by the previous patch, or not
referenced at all for whatever reason).Signed-off-by: Jan Beulich
Signed-off-by: Rusty Russell -
Discard all symbols not interesting for kallsyms use: absolute,
section, and in the common case (!KALLSYMS_ALL) data ones.Signed-off-by: Jan Beulich
Signed-off-by: Rusty Russell
19 Sep, 2009
1 commit
-
Now that the last users of markers have migrated to the event
tracer we can kill off the (now orphan) support code.Signed-off-by: Christoph Hellwig
Acked-by: Mathieu Desnoyers
Cc: Steven Rostedt
Cc: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar
17 Aug, 2009
1 commit
-
Add trace points to trace module_load, module_free, module_get,
module_put and module_request, and use trace_event facility to
get the trace output.Here's the sample output:
TASK-PID CPU# TIMESTAMP FUNCTION
| | | | |
-42 [000] 1.758380: module_request: fb0 wait=1 call_site=fb_open
...
-60 [000] 3.269403: module_load: scsi_wait_scan
-60 [000] 3.269432: module_put: scsi_wait_scan call_site=sys_init_module refcnt=0
-61 [001] 3.273168: module_free: scsi_wait_scan
...
-1021 [000] 13.836081: module_load: sunrpc
-1021 [000] 13.840589: module_put: sunrpc call_site=sys_init_module refcnt=-1
-1027 [000] 13.848098: module_get: sunrpc call_site=try_module_get refcnt=0
-1027 [000] 13.848308: module_get: sunrpc call_site=get_filesystem refcnt=1
-1027 [000] 13.848692: module_put: sunrpc call_site=put_filesystem refcnt=0
...
modprobe-2587 [001] 1088.437213: module_load: trace_events_sample F
modprobe-2587 [001] 1088.437786: module_put: trace_events_sample call_site=sys_init_module refcnt=0Note:
- the taints flag can be 'F', 'C' and/or 'P' if mod->taints != 0
- the module refcnt is percpu, so it can be negative in a
specific cpuSigned-off-by: Li Zefan
Acked-by: Rusty Russell
Cc: Steven Rostedt
Cc: Frederic Weisbecker
Cc: Rusty Russell
LKML-Reference:
Signed-off-by: Ingo Molnar