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GCC 9 introduces a new option, -flive-patching. It disables certain
optimizations which could make a compilation unsafe for later live
patching of the running kernel.
The option is used only if CONFIG_LIVEPATCH is enabled and $(CC)
supports it.
Performance impact of the option was measured on three different
Intel machines - two bigger NUMA boxes and one smaller UMA box. Kernel
intensive (IO, scheduling, networking) benchmarks were selected, plus a
set of HPC workloads from NAS Parallel Benchmark. The tests were done on
upstream kernel 5.0-rc8 with openSUSE Leap 15.0 userspace.
The majority of the tests is unaffected. The only significant exception
is the scheduler section which suffers 1-3% degradation.
Evaluated-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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The atomic replace allows to create cumulative patches. They are useful when
you maintain many livepatches and want to remove one that is lower on the
stack. In addition it is very useful when more patches touch the same function
and there are dependencies between them.
It's also a feature some of the distros are using already to distribute
their patches.
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Ability to send fake signal to blocking tasks automatically, instead of
requiring manual intervention, from Miroslav Benes
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Document change towards group maintainership of livepatching code
samples/ warning fix from Nicholas Mc Guire
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The livepatch selftest functions.sh library uses "$*" and an
intermediate variable to extract and then pass arguments from function
to function call. The effect of this combination is that the argument
list is flattened into a single argument. Sometimes this is benign, but
in cases like __load_mod(), the modprobe invocation will interpret all
the module parameters as a single parameter.
Drop the intermediate variable and use the "$@" special parameter as
described in the bash manual.
Link: https://www.gnu.org/software/bash/manual/bash.html#Special-Parameters
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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Livepatches can no longer get enabled and disabled repeatedly.
The list klp_patches contains only enabled patches and eventually
the patch in transition.
The module coming and going callbacks do no longer need to check
for these state. They have to proceed with all listed patches.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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Add proper error handling when allocating or getting shadow variables
in the selftest. It prevents an invalid pointer access in some situations.
It shows the good programming practice in the others.
The error codes are just the best guess and specific for this particular
test. In general, klp_shadow_alloc() returns NULL also when the given
shadow variable has already been allocated. In addition, both
klp_shadow_alloc() and klp_shadow_get_or_alloc() might fail from
other reasons when the constructor fails.
Note, that the error code is not really important even in the real life.
The use of shadow variables should be transparent for the original
livepatched code.
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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Fixes the following smatch warning:
lib/livepatch/test_klp_shadow_vars.c:47 ptr_id() warn: returning -1 instead of -ENOMEM is sloppy
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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There are already macros to iterate over struct klp_func and klp_object.
Add also klp_for_each_patch(). But make it internal because also
klp_patches list is internal.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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As a result of an unsupported operation is better to use EOPNOTSUPP
as error code.
ENOSYS is only used for 'invalid syscall nr' and nothing else.
Signed-off-by: Alice Ferrazzi <alice.ferrazzi@miraclelinux.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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The livepatch selftest scripts turn on dynamic_debug of livepatch
kernel source to determine expected behavior. TEST_LIVEPATCH should
therefore include DYNAMIC_DEBUG in its list of dependencies.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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Sparse reported warnings about non-static symbols. For the variables
a simple static attribute is fine - for the functions referenced by
livepatch via klp_func the symbol-names must be unmodified in the
symbol table and the patchable code has to be emitted. The resolution
is to attach __used attribute to the shared statically declared functions.
Link: https://lore.kernel.org/lkml/1544965657-26804-1-git-send-email-hofrat@osadl.org/
Suggested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Update MAINTAINERS for livepatching to reflect status quo better.
Also move the tree to a shared location, as we are moving more
towards group maintainership model.
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The fake signal is send automatically now. We can rely on it completely
and remove the sysfs attribute.
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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An administrator may send a fake signal to all remaining blocking tasks
of a running transition by writing to
/sys/kernel/livepatch/<patch>/signal attribute. Let's do it
automatically after 15 seconds. The timeout is chosen deliberately. It
gives the tasks enough time to transition themselves.
Theoretically, sending it once should be more than enough. However,
every task must get outside of a patched function to be successfully
transitioned. It could prove not to be simple and resending could be
helpful in that case.
A new workqueue job could be a cleaner solution to achieve it, but it
could also introduce deadlocks and cause more headaches with
synchronization and cancelling.
[jkosina@suse.cz: removed added newline]
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Add a few livepatch modules and simple target modules that the included
regression suite can run tests against:
- basic livepatching (multiple patches, atomic replace)
- pre/post (un)patch callbacks
- shadow variable API
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Tested-by: Miroslav Benes <mbenes@suse.cz>
Tested-by: Alice Ferrazzi <alice.ferrazzi@gmail.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The atomic replace and cumulative patches were introduced as a more secure
way to handle dependent patches. They simplify the logic:
+ Any new cumulative patch is supposed to take over shadow variables
and changes made by callbacks from previous livepatches.
+ All replaced patches are discarded and the modules can be unloaded.
As a result, there is only one scenario when a cumulative livepatch
gets disabled.
The different handling of "normal" and cumulative patches might cause
confusion. It would make sense to keep only one mode. On the other hand,
it would be rude to enforce using the cumulative livepatches even for
trivial and independent (hot) fixes.
However, the stack of patches is not really necessary any longer.
The patch ordering was never clearly visible via the sysfs interface.
Also the "normal" patches need a lot of caution anyway.
Note that the list of enabled patches is still necessary but the ordering
is not longer enforced.
Otherwise, the code is ready to disable livepatches in an random order.
Namely, klp_check_stack_func() always looks for the function from
the livepatch that is being disabled. klp_func structures are just
removed from the related func_stack. Finally, the ftrace handlers
is removed only when the func_stack becomes empty.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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User documentation for the atomic replace feature. It makes it easier
to maintain livepatches using so-called cumulative patches.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Replaced patches are removed from the stack when the transition is
finished. It means that Nop structures will never be needed again
and can be removed. Why should we care?
+ Nop structures give the impression that the function is patched
even though the ftrace handler has no effect.
+ Ftrace handlers do not come for free. They cause slowdown that might
be visible in some workloads. The ftrace-related slowdown might
actually be the reason why the function is no longer patched in
the new cumulative patch. One would expect that cumulative patch
would help solve these problems as well.
+ Cumulative patches are supposed to replace any earlier version of
the patch. The amount of NOPs depends on which version was replaced.
This multiplies the amount of scenarios that might happen.
One might say that NOPs are innocent. But there are even optimized
NOP instructions for different processors, for example, see
arch/x86/kernel/alternative.c. And klp_ftrace_handler() is much
more complicated.
+ It sounds natural to clean up a mess that is no longer needed.
It could only be worse if we do not do it.
This patch allows to unpatch and free the dynamic structures independently
when the transition finishes.
The free part is a bit tricky because kobject free callbacks are called
asynchronously. We could not wait for them easily. Fortunately, we do
not have to. Any further access can be avoided by removing them from
the dynamic lists.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Sometimes we would like to revert a particular fix. Currently, this
is not easy because we want to keep all other fixes active and we
could revert only the last applied patch.
One solution would be to apply new patch that implemented all
the reverted functions like in the original code. It would work
as expected but there will be unnecessary redirections. In addition,
it would also require knowing which functions need to be reverted at
build time.
Another problem is when there are many patches that touch the same
functions. There might be dependencies between patches that are
not enforced on the kernel side. Also it might be pretty hard to
actually prepare the patch and ensure compatibility with the other
patches.
Atomic replace && cumulative patches:
A better solution would be to create cumulative patch and say that
it replaces all older ones.
This patch adds a new "replace" flag to struct klp_patch. When it is
enabled, a set of 'nop' klp_func will be dynamically created for all
functions that are already being patched but that will no longer be
modified by the new patch. They are used as a new target during
the patch transition.
The idea is to handle Nops' structures like the static ones. When
the dynamic structures are allocated, we initialize all values that
are normally statically defined.
The only exception is "new_func" in struct klp_func. It has to point
to the original function and the address is known only when the object
(module) is loaded. Note that we really need to set it. The address is
used, for example, in klp_check_stack_func().
Nevertheless we still need to distinguish the dynamically allocated
structures in some operations. For this, we add "nop" flag into
struct klp_func and "dynamic" flag into struct klp_object. They
need special handling in the following situations:
+ The structures are added into the lists of objects and functions
immediately. In fact, the lists were created for this purpose.
+ The address of the original function is known only when the patched
object (module) is loaded. Therefore it is copied later in
klp_init_object_loaded().
+ The ftrace handler must not set PC to func->new_func. It would cause
infinite loop because the address points back to the beginning of
the original function.
+ The various free() functions must free the structure itself.
Note that other ways to detect the dynamic structures are not considered
safe. For example, even the statically defined struct klp_object might
include empty funcs array. It might be there just to run some callbacks.
Also note that the safe iterator must be used in the free() functions.
Otherwise already freed structures might get accessed.
Special callbacks handling:
The callbacks from the replaced patches are _not_ called by intention.
It would be pretty hard to define a reasonable semantic and implement it.
It might even be counter-productive. The new patch is cumulative. It is
supposed to include most of the changes from older patches. In most cases,
it will not want to call pre_unpatch() post_unpatch() callbacks from
the replaced patches. It would disable/break things for no good reasons.
Also it should be easier to handle various scenarios in a single script
in the new patch than think about interactions caused by running many
scripts from older patches. Not to say that the old scripts even would
not expect to be called in this situation.
Removing replaced patches:
One nice effect of the cumulative patches is that the code from the
older patches is no longer used. Therefore the replaced patches can
be removed. It has several advantages:
+ Nops' structs will no longer be necessary and might be removed.
This would save memory, restore performance (no ftrace handler),
allow clear view on what is really patched.
+ Disabling the patch will cause using the original code everywhere.
Therefore the livepatch callbacks could handle only one scenario.
Note that the complication is already complex enough when the patch
gets enabled. It is currently solved by calling callbacks only from
the new cumulative patch.
+ The state is clean in both the sysfs interface and lsmod. The modules
with the replaced livepatches might even get removed from the system.
Some people actually expected this behavior from the beginning. After all
a cumulative patch is supposed to "completely" replace an existing one.
It is like when a new version of an application replaces an older one.
This patch does the first step. It removes the replaced patches from
the list of patches. It is safe. The consistency model ensures that
they are no longer used. By other words, each process works only with
the structures from klp_transition_patch.
The removal is done by a special function. It combines actions done by
__disable_patch() and klp_complete_transition(). But it is a fast
track without all the transaction-related stuff.
Signed-off-by: Jason Baron <jbaron@akamai.com>
[pmladek@suse.com: Split, reuse existing code, simplified]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Currently klp_patch contains a pointer to a statically allocated array of
struct klp_object and struct klp_objects contains a pointer to a statically
allocated array of klp_func. In order to allow for the dynamic allocation
of objects and functions, link klp_patch, klp_object, and klp_func together
via linked lists. This allows us to more easily allocate new objects and
functions, while having the iterator be a simple linked list walk.
The static structures are added to the lists early. It allows to add
the dynamically allocated objects before klp_init_object() and
klp_init_func() calls. Therefore it reduces the further changes
to the code.
This patch does not change the existing behavior.
Signed-off-by: Jason Baron <jbaron@akamai.com>
[pmladek@suse.com: Initialize lists before init calls]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The possibility to re-enable a registered patch was useful for immediate
patches where the livepatch module had to stay until the system reboot.
The improved consistency model allows to achieve the same result by
unloading and loading the livepatch module again.
Also we are going to add a feature called atomic replace. It will allow
to create a patch that would replace all already registered patches.
The aim is to handle dependent patches more securely. It will obsolete
the stack of patches that helped to handle the dependencies so far.
Then it might be unclear when a cumulative patch re-enabling is safe.
It would be complicated to support the many modes. Instead we could
actually make the API and code easier to understand.
Therefore, remove the two step public API. All the checks and init calls
are moved from klp_register_patch() to klp_enabled_patch(). Also the patch
is automatically freed, including the sysfs interface when the transition
to the disabled state is completed.
As a result, there is never a disabled patch on the top of the stack.
Therefore we do not need to check the stack in __klp_enable_patch().
And we could simplify the check in __klp_disable_patch().
Also the API and logic is much easier. It is enough to call
klp_enable_patch() in module_init() call. The patch can be disabled
by writing '0' into /sys/kernel/livepatch/<patch>/enabled. Then the module
can be removed once the transition finishes and sysfs interface is freed.
The only problem is how to free the structures and kobjects safely.
The operation is triggered from the sysfs interface. We could not put
the related kobject from there because it would cause lock inversion
between klp_mutex and kernfs locks, see kn->count lockdep map.
Therefore, offload the free task to a workqueue. It is perfectly fine:
+ The patch can no longer be used in the livepatch operations.
+ The module could not be removed until the free operation finishes
and module_put() is called.
+ The operation is asynchronous already when the first
klp_try_complete_transition() fails and another call
is queued with a delay.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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module_put() is currently never called in klp_complete_transition() when
klp_force is set. As a result, we might keep the reference count even when
klp_enable_patch() fails and klp_cancel_transition() is called.
This might give the impression that a module might get blocked in some
strange init state. Fortunately, it is not the case. The reference count
is ignored when mod->init fails and erroneous modules are always removed.
Anyway, this might be confusing. Instead, this patch moves
the global klp_forced flag into struct klp_patch. As a result,
we block only modules that might still be in use after a forced
transition. Newly loaded livepatches might be eventually completely
removed later.
It is not a big deal. But the code is at least consistent with
the reality.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The code for freeing livepatch structures is a bit scattered and tricky:
+ direct calls to klp_free_*_limited() and kobject_put() are
used to release partially initialized objects
+ klp_free_patch() removes the patch from the public list
and releases all objects except for patch->kobj
+ object_put(&patch->kobj) and the related wait_for_completion()
are called directly outside klp_mutex; this code is duplicated;
Now, we are going to remove the registration stage to simplify the API
and the code. This would require handling more situations in
klp_enable_patch() error paths.
More importantly, we are going to add a feature called atomic replace.
It will need to dynamically create func and object structures. We will
want to reuse the existing init() and free() functions. This would
create even more error path scenarios.
This patch implements more straightforward free functions:
+ checks kobj_added flag instead of @limit[*]
+ initializes patch->list early so that the check for empty list
always works
+ The action(s) that has to be done outside klp_mutex are done
in separate klp_free_patch_finish() function. It waits only
when patch->kobj was really released via the _start() part.
The patch does not change the existing behavior.
[*] We need our own flag to track that the kobject was successfully
added to the hierarchy. Note that kobj.state_initialized only
indicates that kobject has been initialized, not whether is has
been added (and needs to be removed on cleanup).
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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We are going to simplify the API and code by removing the registration
step. This would require calling init/free functions from enable/disable
ones.
This patch just moves the code to prevent more forward declarations.
This patch does not change the code except for two forward declarations.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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The address of the to be patched function and new function is stored
in struct klp_func as:
void *new_func;
unsigned long old_addr;
The different naming scheme and type are derived from the way
the addresses are set. @old_addr is assigned at runtime using
kallsyms-based search. @new_func is statically initialized,
for example:
static struct klp_func funcs[] = {
{
.old_name = "cmdline_proc_show",
.new_func = livepatch_cmdline_proc_show,
}, { }
};
This patch changes unsigned long old_addr -> void *old_func. It removes
some confusion when these address are later used in the code. It is
motivated by a followup patch that adds special NOP struct klp_func
where we want to assign func->new_func = func->old_addr respectively
func->new_func = func->old_func.
This patch does not modify the existing behavior.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Alice Ferrazzi <alice.ferrazzi@gmail.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatch update from Jiri Kosina:
"Return value checking fixup in livepatching samples, from Nicholas Mc
Guire"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
livepatch: check kzalloc return values
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git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal management updates from Zhang Rui:
- Add locking for cooling device sysfs attribute in case the cooling
device state is changed by userspace and thermal framework
simultaneously. (Thara Gopinath)
- Fix a problem that passive cooling is reset improperly after system
suspend/resume. (Wei Wang)
- Cleanup the driver/thermal/ directory by moving intel and qcom
platform specific drivers to platform specific sub-directories. (Amit
Kucheria)
- Some trivial cleanups. (Lukasz Luba, Wolfram Sang)
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal/intel: fixup for Kconfig string parsing tightening up
drivers: thermal: Move QCOM_SPMI_TEMP_ALARM into the qcom subdir
drivers: thermal: Move various drivers for intel platforms into a subdir
thermal: Fix locking in cooling device sysfs update cur_state
Thermal: do not clear passive state during system sleep
thermal: zx2967_thermal: simplify getting .driver_data
thermal: st: st_thermal: simplify getting .driver_data
thermal: spear_thermal: simplify getting .driver_data
thermal: rockchip_thermal: simplify getting .driver_data
thermal: int340x_thermal: int3400_thermal: simplify getting .driver_data
thermal: remove unused function parameter
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git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
Pull thermal SoC updates from Eduardo Valentin:
- Tegra DT binding documentation for Tegra194
- Armada now supports ap806 and cp110
- RCAR thermal now supports R8A774C0 and R8A77990
- Fixes on thermal_hwmon, IMX, generic-ADC, ST, RCAR, Broadcom,
Uniphier, QCOM, Tegra, PowerClamp, and Armada thermal drivers.
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal: (22 commits)
thermal: generic-adc: Fix adc to temp interpolation
thermal: rcar_thermal: add R8A77990 support
dt-bindings: thermal: rcar-thermal: add R8A77990 support
thermal: rcar_thermal: add R8A774C0 support
dt-bindings: thermal: rcar-thermal: add R8A774C0 support
dt-bindings: cp110: document the thermal interrupt capabilities
dt-bindings: ap806: document the thermal interrupt capabilities
MAINTAINERS: thermal: add entry for Marvell MVEBU thermal driver
thermal: armada: add overheat interrupt support
thermal: st: fix Makefile typo
thermal: uniphier: Convert to SPDX identifier
thermal/intel_powerclamp: Change to use DEFINE_SHOW_ATTRIBUTE macro
thermal: tegra: soctherm: Change to use DEFINE_SHOW_ATTRIBUTE macro
dt-bindings: thermal: tegra-bpmp: Add Tegra194 support
thermal: imx: save one condition block for normal case of nvmem initialization
thermal: imx: fix for dependency on cpu-freq
thermal: tsens: qcom: do not create duplicate regmap debugfs entries
thermal: armada: Use PTR_ERR_OR_ZERO in armada_thermal_probe_legacy()
dt-bindings: thermal: rcar-gen3-thermal: All variants use 3 interrupts
thermal: broadcom: use devm_thermal_zone_of_sensor_register
...
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace sh build fix from Steven Rostedt:
"It appears that the zero-day bot did find a bug in my sh build.
And that I didn't have the bad code in my config file when I cross
compiled it, although there are a few other errors in sh that makes it
not build for me, I missed that I added one more"
* tag 'trace-v4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
sh: ftrace: Fix missing parenthesis in WARN_ON()
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Pull smb3 fixes from Steve French:
"Three fixes, one for stable, one adds the (most secure) SMB3.1.1
dialect to default list requested"
* tag '4.21-smb3-small-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb3: add smb3.1.1 to default dialect list
cifs: fix confusing warning message on reconnect
smb3: fix large reads on encrypted connections
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Pull iomap maintainer update from Darrick Wong:
"Christoph Hellwig and I have decided to take responsibility for the fs
iomap code rather than let it languish further"
* tag 'iomap-4.21-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: take responsibility for the filesystem iomap code
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Pull xfs fixlets from Darrick Wong:
"Remove a couple of unnecessary local variables"
* tag 'xfs-4.21-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: xfs_fsops: drop useless LIST_HEAD
xfs: xfs_buf: drop useless LIST_HEAD
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Pull ceph updates from Ilya Dryomov:
"A fairly quiet round: a couple of messenger performance improvements
from myself and a few cap handling fixes from Zheng"
* tag 'ceph-for-4.21-rc1' of git://github.com/ceph/ceph-client:
ceph: don't encode inode pathes into reconnect message
ceph: update wanted caps after resuming stale session
ceph: skip updating 'wanted' caps if caps are already issued
ceph: don't request excl caps when mount is readonly
ceph: don't update importing cap's mseq when handing cap export
libceph: switch more to bool in ceph_tcp_sendmsg()
libceph: use MSG_SENDPAGE_NOTLAST with ceph_tcp_sendpage()
libceph: use sock_no_sendpage() as a fallback in ceph_tcp_sendpage()
libceph: drop last_piece logic from write_partial_message_data()
ceph: remove redundant assignment
ceph: cleanup splice_dentry()
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Fixes build break on most ARM/ARM64 defconfigs:
lib/genalloc.c: In function 'gen_pool_add_virt':
lib/genalloc.c:190:10: error: implicit declaration of function 'vzalloc_node'; did you mean 'kzalloc_node'?
lib/genalloc.c:190:8: warning: assignment to 'struct gen_pool_chunk *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
lib/genalloc.c: In function 'gen_pool_destroy':
lib/genalloc.c:254:3: error: implicit declaration of function 'vfree'; did you mean 'kfree'?
Fixes: 6862d2fc8185 ('lib/genalloc.c: use vzalloc_node() to allocate the bitmap')
Cc: Huang Shijie <sjhuang@iluvatar.ai>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Skidanov <alexey.skidanov@intel.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount API prep from Al Viro:
"Mount API prereqs.
Mostly that's LSM mount options cleanups. There are several minor
fixes in there, but nothing earth-shattering (leaks on failure exits,
mostly)"
* 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (27 commits)
mount_fs: suppress MAC on MS_SUBMOUNT as well as MS_KERNMOUNT
smack: rewrite smack_sb_eat_lsm_opts()
smack: get rid of match_token()
smack: take the guts of smack_parse_opts_str() into a new helper
LSM: new method: ->sb_add_mnt_opt()
selinux: rewrite selinux_sb_eat_lsm_opts()
selinux: regularize Opt_... names a bit
selinux: switch away from match_token()
selinux: new helper - selinux_add_opt()
LSM: bury struct security_mnt_opts
smack: switch to private smack_mnt_opts
selinux: switch to private struct selinux_mnt_opts
LSM: hide struct security_mnt_opts from any generic code
selinux: kill selinux_sb_get_mnt_opts()
LSM: turn sb_eat_lsm_opts() into a method
nfs_remount(): don't leak, don't ignore LSM options quietly
btrfs: sanitize security_mnt_opts use
selinux; don't open-code a loop in sb_finish_set_opts()
LSM: split ->sb_set_mnt_opts() out of ->sb_kern_mount()
new helper: security_sb_eat_lsm_opts()
...
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull trivial vfs updates from Al Viro:
"A few cleanups + Neil's namespace_unlock() optimization"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
exec: make prepare_bprm_creds static
genheaders: %-<width>s had been there since v6; %-*s - since v7
VFS: use synchronize_rcu_expedited() in namespace_unlock()
iov_iter: reduce code duplication
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git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS fixes from Paul Burton:
"A few early MIPS fixes for 4.21:
- The Broadcom BCM63xx platform sees a fix for resetting the BCM6368
ethernet switch, and the removal of a platform device we've never
had a driver for.
- The Alchemy platform sees a few fixes for bitrot that occurred
within the past few cycles.
- We now enable vectored interrupt support for the MediaTek MT7620
SoC, which makes sense since they're supported by the SoC but in
this case also works around a bug relating to the location of
exception vectors when using a recent version of U-Boot.
- The atomic64_fetch_*_relaxed() family of functions see a fix for a
regression in MIPS64 kernels since v4.19.
- Cavium Octeon III CN7xxx systems will now disable their RGMII
interfaces rather than attempt to enable them & warn about the lack
of support for doing so, as they did since initial CN7xxx ethernet
support was added in v4.7.
- The Microsemi/Microchip MSCC SoCs gain a MAINTAINERS entry.
- .mailmap now provides consistency for Dengcheng Zhu's name &
current email address"
* tag 'mips_fixes_4.21_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: OCTEON: mark RGMII interface disabled on OCTEON III
MIPS: Fix a R10000_LLSC_WAR logic in atomic.h
MIPS: BCM63XX: drop unused and broken DSP platform device
mailmap: Update name spelling and email for Dengcheng Zhu
MIPS: ralink: Select CONFIG_CPU_MIPSR2_IRQ_VI on MT7620/8
MAINTAINERS: Add a maintainer for MSCC MIPS SoCs
MIPS: Alchemy: update dma masks for devboard devices
MIPS: Alchemy: update cpu-feature-overrides
MIPS: Alchemy: drop DB1000 IrDA support bits
MIPS: alchemy: cpu_all_mask is forbidden for clock event devices
MIPS: BCM63XX: fix switch core reset on BCM6368
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"A fix for the recent access_ok() change, which broke the build. We
recently added a use of type in order to squash a warning elsewhere
about type being unused.
A handful of other minor build fixes, and one defconfig update.
Thanks to: Christian Lamparter, Christophe Leroy, Diana Craciun,
Mathieu Malaterre"
* tag 'powerpc-4.21-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Drop use of 'type' from access_ok()
KVM: PPC: Book3S HV: radix: Fix uninitialized var build error
powerpc/configs: Add PPC4xx_OCM to ppc40x_defconfig
powerpc/4xx/ocm: Fix phys_addr_t printf warnings
powerpc/4xx/ocm: Fix compilation error due to PAGE_KERNEL usage
powerpc/fsl: Fixed warning: orphan section `__btb_flush_fixup'
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git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fix from Helge Deller:
"Fix boot issues with a series of parisc servers since kernel 4.20.
Remapping kernel text with set_kernel_text_rw() missed to remap from
lowest up until the highest huge-page aligned kernel text addresss"
* 'parisc-4.21-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Remap hugepage-aligned pages in set_kernel_text_rw()
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Pull h8300 fix from Yoshinori Sato:
"Build problem fix"
* tag 'for-4.21' of git://git.sourceforge.jp/gitroot/uclinux-h8/linux:
h8300: pci: Remove local declaration of pcibios_penalize_isa_irq
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git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull more ARM SoC updates from Olof Johansson:
"A few updates that we merged late but are low risk for regressions for
other platforms (and a few other straggling patches):
- I mis-tagged the 'drivers' branch, and missed 3 patches. Merged in
here. They're for a driver for the PL353 SRAM controller and a
build fix for the qualcomm scm driver.
- A new platform, RDA Micro RDA8810PL (Cortex-A5 w/ integrated
Vivante GPU, 256MB RAM, Wifi). This includes some acked
platform-specific drivers (serial, etc). This also include DTs for
two boards with this SoC, OrangePi 2G and OrangePi i86.
- i.MX8 is another new platform (NXP, 4x Cortex-A53 + Cortex-M4, 4K
video playback offload). This is the first i.MX 64-bit SoC.
- Some minor updates to Samsung boards (adding a few peripherals in
DTs).
- Small rework for SMP bootup on STi platforms.
- A couple of TEE driver fixes.
- A couple of new config options (bcm2835 thermal, Uniphier MDMAC)
enabled in defconfigs"
* tag 'armsoc-late' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (27 commits)
ARM: multi_v7_defconfig: enable CONFIG_UNIPHIER_MDMAC
arm64: defconfig: Re-enable bcm2835-thermal driver
MAINTAINERS: Add entry for RDA Micro SoC architecture
tty: serial: Add RDA8810PL UART driver
ARM: dts: rda8810pl: Add interrupt support for UART
dt-bindings: serial: Document RDA Micro UART
ARM: dts: rda8810pl: Add timer support
ARM: dts: Add devicetree for OrangePi i96 board
ARM: dts: Add devicetree for OrangePi 2G IoT board
ARM: dts: Add devicetree for RDA8810PL SoC
ARM: Prepare RDA8810PL SoC
dt-bindings: arm: Document RDA8810PL and reference boards
dt-bindings: Add RDA Micro vendor prefix
ARM: sti: remove pen_release and boot_lock
arm64: dts: exynos: Add Bluetooth chip to TM2(e) boards
arm64: dts: imx8mq-evk: enable watchdog
arm64: dts: imx8mq: add watchdog devices
MAINTAINERS: add i.MX8 DT path to i.MX architecture
arm64: add support for i.MX8M EVK board
arm64: add basic DTS for i.MX8MQ
...
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"I'm safely chained back up to my desk, so please pull these arm64
fixes for -rc1 that address some issues that cropped up during the
merge window:
- Prevent KASLR from mapping the top page of the virtual address
space
- Fix device-tree probing of SDEI driver
- Fix incorrect register offset definition in Hisilicon DDRC PMU
driver
- Fix compilation issue with older binutils not liking unsigned
immediates
- Fix uapi headers so that libc can provide its own sigcontext
definition
- Fix handling of private compat syscalls
- Hook up compat io_pgetevents() syscall for 32-bit tasks
- Cleanup to arm64 Makefile (including now to avoid silly conflicts)"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: compat: Hook up io_pgetevents() for 32-bit tasks
arm64: compat: Don't pull syscall number from regs in arm_compat_syscall
arm64: compat: Avoid sending SIGILL for unallocated syscall numbers
arm64/sve: Disentangle <uapi/asm/ptrace.h> from <uapi/asm/sigcontext.h>
arm64/sve: ptrace: Fix SVE_PT_REGS_OFFSET definition
drivers/perf: hisi: Fixup one DDRC PMU register offset
arm64: replace arm64-obj-* in Makefile with obj-*
arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region
firmware: arm_sdei: Fix DT platform device creation
firmware: arm_sdei: fix wrong of_node_put() in init function
arm64: entry: remove unused register aliases
arm64: smp: Fix compilation error
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Pull ARM updates from Russell King:
"Included in this update:
- Florian Fainelli noticed that userspace segfaults caused by the
lack of kernel-userspace helpers was hard to diagnose; we now issue
a warning when userspace tries to use the helpers but the kernel
has them disabled.
- Ben Dooks wants compatibility for the old ATAG serial number with
DT systems.
- Some cleanup of assembly by Nicolas Pitre.
- User accessors optimisation from Vincent Whitchurch.
- More robust kdump on SMP systems from Yufen Wang.
- Sebastian Andrzej Siewior noticed problems with the SMP "boot_lock"
on RT kernels, and so we convert the Versatile series of platforms
to use a raw spinlock instead, consolidating the Versatile
implementation. We entirely remove the boot_lock on OMAP systems,
where it's unnecessary. Further patches for other systems will be
submitted for the following merge window.
- Start switching old StrongARM-11x0 systems to use gpiolib rather
than their private GPIO implementation - mostly PCMCIA bits.
- ARM Kconfig cleanups.
- Cleanup a mostly harmless mistake in the recent Spectre patch in
4.20 (which had the effect that data that can be placed into the
init sections was incorrectly always placed in the rodata section)"
* tag 'for-4.21' of git://git.armlinux.org.uk/~rmk/linux-arm: (25 commits)
ARM: omap2: remove unnecessary boot_lock
ARM: versatile: rename and comment SMP implementation
ARM: versatile: convert boot_lock to raw
ARM: vexpress/realview: consolidate immitation CPU hotplug
ARM: fix the cockup in the previous patch
ARM: sa1100/cerf: switch to using gpio_led_register_device()
ARM: sa1100/assabet: switch to using gpio leds
ARM: sa1100/assabet: add gpio keys support for right-hand two buttons
ARM: sa1111: remove legacy GPIO interfaces
pcmcia: sa1100*: remove redundant bvd1/bvd2 setting
ARM: pxa/lubbock: switch PCMCIA to MAX1600 library
ARM: pxa/mainstone: switch PCMCIA to MAX1600 library and gpiod APIs
ARM: sa1100/neponset: switch PCMCIA to MAX1600 library and gpiod APIs
ARM: sa1100/jornada720: switch PCMCIA to gpiod APIs
pcmcia: add MAX1600 library
ARM: sa1100: explicitly register sa11x0-pcmcia devices
ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+
ARM: 8812/1: Optimise copy_{from/to}_user for !CPU_USE_DOMAINS
ARM: 8811/1: always list both ldrd/strd registers explicitly
ARM: 8808/1: kexec:offline panic_smp_self_stop CPU
...
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Pull arch/csky updates from Guo Ren:
"Here are three main features (cpu_hotplug, basic ftrace, basic perf)
and some bugfixes:
Features:
- Add CPU-hotplug support for SMP
- Add ftrace with function trace and function graph trace
- Add Perf support
- Add EM_CSKY_OLD 39
- optimize kernel panic print.
- remove syscall_exit_work
Bugfixes:
- fix abiv2 mmap(... O_SYNC) failure
- fix gdb coredump error
- remove vdsp implement for kernel
- fix qemu failure to bootup sometimes
- fix ftrace call-graph panic
- fix device tree node reference leak
- remove meaningless header-y
- fix save hi,lo,dspcr regs in switch_stack
- remove unused members in processor.h"
* tag 'csky-for-linus-4.21' of git://github.com/c-sky/csky-linux:
csky: Add perf support for C-SKY
csky: Add EM_CSKY_OLD 39
clocksource/drivers/c-sky: fixup ftrace call-graph panic
csky: ftrace call graph supported.
csky: basic ftrace supported
csky: remove unused members in processor.h
csky: optimize kernel panic print.
csky: stacktrace supported.
csky: CPU-hotplug supported for SMP
clocksource/drivers/c-sky: fixup qemu fail to bootup sometimes.
csky: fixup save hi,lo,dspcr regs in switch_stack.
csky: remove syscall_exit_work
csky: fixup remove vdsp implement for kernel.
csky: bugfix gdb coredump error.
csky: fixup abiv2 mmap(... O_SYNC) failed.
csky: define syscall_get_arch()
elf-em.h: add EM_CSKY
csky: remove meaningless header-y
csky: Don't leak device tree node reference
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Merge more updates from Andrew Morton:
- procfs updates
- various misc bits
- lib/ updates
- epoll updates
- autofs
- fatfs
- a few more MM bits
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (58 commits)
mm/page_io.c: fix polled swap page in
checkpatch: add Co-developed-by to signature tags
docs: fix Co-Developed-by docs
drivers/base/platform.c: kmemleak ignore a known leak
fs: don't open code lru_to_page()
fs/: remove caller signal_pending branch predictions
mm/: remove caller signal_pending branch predictions
arch/arc/mm/fault.c: remove caller signal_pending_branch predictions
kernel/sched/: remove caller signal_pending branch predictions
kernel/locking/mutex.c: remove caller signal_pending branch predictions
mm: select HAVE_MOVE_PMD on x86 for faster mremap
mm: speed up mremap by 20x on large regions
mm: treewide: remove unused address argument from pte_alloc functions
initramfs: cleanup incomplete rootfs
scripts/gdb: fix lx-version string output
kernel/kcov.c: mark write_comp_data() as notrace
kernel/sysctl: add panic_print into sysctl
panic: add options to print system info when panic happens
bfs: extra sanity checking and static inode bitmap
exec: separate MM_ANONPAGES and RLIMIT_STACK accounting
...
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Some non-generic ia64 configs don't build swiotlb, and thus should not
pull in the generic non-coherent DMA infrastructure.
Fixes: 68c608345c ("swiotlb: remove dma_mark_clean")
Reported-by: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This has been broken forever, and nobody ever really noticed because
it's purely a performance issue.
Long long ago, in commit 6175ddf06b61 ("x86: Clean up mem*io functions")
Brian Gerst simplified the memory copies to and from iomem, since on
x86, the instructions to access iomem are exactly the same as the
regular instructions.
That is technically true, and things worked, and nobody said anything.
Besides, back then the regular memcpy was pretty simple and worked fine.
Nobody noticed except for David Laight, that is. David has a testing a
TLP monitor he was writing for an FPGA, and has been occasionally
complaining about how memcpy_toio() writes things one byte at a time.
Which is completely unacceptable from a performance standpoint, even if
it happens to technically work.
The reason it's writing one byte at a time is because while it's
technically true that accesses to iomem are the same as accesses to
regular memory on x86, the _granularity_ (and ordering) of accesses
matter to iomem in ways that they don't matter to regular cached memory.
In particular, when ERMS is set, we default to using "rep movsb" for
larger memory copies. That is indeed perfectly fine for real memory,
since the whole point is that the CPU is going to do cacheline
optimizations and executes the memory copy efficiently for cached
memory.
With iomem? Not so much. With iomem, "rep movsb" will indeed work, but
it will copy things one byte at a time. Slowly and ponderously.
Now, originally, back in 2010 when commit 6175ddf06b61 was done, we
didn't use ERMS, and this was much less noticeable.
Our normal memcpy() was simpler in other ways too.
Because in fact, it's not just about using the string instructions. Our
memcpy() these days does things like "read and write overlapping values"
to handle the last bytes of the copy. Again, for normal memory,
overlapping accesses isn't an issue. For iomem? It can be.
So this re-introduces the specialized memcpy_toio(), memcpy_fromio() and
memset_io() functions. It doesn't particularly optimize them, but it
tries to at least not be horrid, or do overlapping accesses. In fact,
this uses the existing __inline_memcpy() function that we still had
lying around that uses our very traditional "rep movsl" loop followed by
movsw/movsb for the final bytes.
Somebody may decide to try to improve on it, but if we've gone almost a
decade with only one person really ever noticing and complaining, maybe
it's not worth worrying about further, once it's not _completely_ broken?
Reported-by: David Laight <David.Laight@aculab.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This actually enables the __put_user_goto() functionality in
unsafe_put_user().
For an example of the effect of this, this is the code generated for the
unsafe_put_user(signo, &infop->si_signo, Efault);
in the waitid() system call:
movl %ecx,(%rbx) # signo, MEM[(struct __large_struct *)_2]
It's just one single store instruction, along with generating an
exception table entry pointing to the Efault label case in case that
instruction faults.
Before, we would generate this:
xorl %edx, %edx
movl %ecx,(%rbx) # signo, MEM[(struct __large_struct *)_3]
testl %edx, %edx
jne .L309
with the exception table generated for that 'mov' instruction causing us
to jump to a stub that set %edx to -EFAULT and then jumped back to the
'testl' instruction.
So not only do we now get rid of the extra code in the normal sequence,
we also avoid unnecessarily keeping that extra error register live
across it all.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This is finally the actual reason for the odd error handling in the
"unsafe_get/put_user()" functions, introduced over three years ago.
Using a "jump to error label" interface is somewhat odd, but very
convenient as a programming interface, and more importantly, it fits
very well with simply making the target be the exception handler address
directly from the inline asm.
The reason it took over three years to actually do this? We need "asm
goto" support for it, which only became the default on x86 last year.
It's now been a year that we've forced asm goto support (see commit
e501ce957a78 "x86: Force asm-goto"), and so let's just do it here too.
[ Side note: this commit was originally done back in 2016. The above
commentary about timing is obviously about it only now getting merged
into my real upstream tree - Linus ]
Sadly, gcc still only supports "asm goto" with asms that do not have any
outputs, so we are limited to only the put_user case for this. Maybe in
several more years we can do the get_user case too.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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