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Patch series "Increase the number of bits available in page_type".
Kent wants more than 16 bits in page_type, so I resurrected this old patch
and expanded it a bit. It's a bit more efficient than our current scheme
(1 4-byte insn vs 3 insns of 13 bytes total) to test a single page type.
This patch (of 4):
An upcoming patch will convert page type from being a bitfield to a
single byte, so we will not be able to use %pG to print the page type
any more. The printing of the symbolic name will be restored in that
patch.
Link: https://lkml.kernel.org/r/20240821173914.2270383-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20240821173914.2270383-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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We only had a couple of array[] declarations, and changing them to just
use 'MAX()' instead of 'max()' fixes the issue.
This will allow us to simplify our min/max macros enormously, since they
can now unconditionally use temporary variables to avoid using the
argument values multiple times.
Cc: David Laight <David.Laight@aculab.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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On the next step it's going to get folded into a field where flags will go.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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A refcount issue can appeared in __fwnode_link_del() due to the
pr_debug() call:
WARNING: CPU: 0 PID: 901 at lib/refcount.c:25 refcount_warn_saturate+0xe5/0x110
Call Trace:
<TASK>
...
of_node_get+0x1e/0x30
of_fwnode_get+0x28/0x40
fwnode_full_name_string+0x34/0x90
fwnode_string+0xdb/0x140
...
vsnprintf+0x17b/0x630
...
__fwnode_link_del+0x25/0xa0
fwnode_links_purge+0x39/0xb0
of_node_release+0xd9/0x180
...
Indeed, an fwnode (of_node) is being destroyed and so, of_node_release()
is called because the of_node refcount reached 0.
From of_node_release() several function calls are done and lead to
a pr_debug() calls with %pfwf to print the fwnode full name.
The issue is not present if we change %pfwf to %pfwP.
To print the full name, %pfwf iterates over the current node and its
parents and obtain/drop a reference to all nodes involved.
In order to allow to print the full name (%pfwf) of a node while it is
being destroyed, do not obtain/drop a reference to this current node.
Fixes: a92eb7621b9f ("lib/vsprintf: Make use of fwnode API to obtain node names and separators")
Cc: stable@vger.kernel.org
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20231114152655.409331-1-herve.codina@bootlin.com
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* uninline simple_strntoull(),
gcc overinlines and this function is not performance critical
* reorder arguments, so that appending INT_MAX as 4th argument
generates very efficient tail call
Space savings:
add/remove: 1/0 grow/shrink: 0/3 up/down: 27/-179 (-152)
Function old new delta
simple_strntoll - 27 +27
simple_strtoull 15 10 -5
simple_strtoll 41 7 -34
vsscanf 1930 1790 -140
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/all/82a2af6e-9b6c-4a09-89d7-ca90cc1cdad1@p183/
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Patch series "lib/vsprintf: Rework header inclusions", v3.
Some patches that reduce the mess with the header inclusions related to
vsprintf.c module. Each patch has its own description, and has no
dependencies to each other, except the collisions over modifications of
the same places. Hence the series.
This patch (of 2):
kernel.h is being used as a dump for all kinds of stuff for a long time.
sprintf() and friends are used in many drivers without need of the full
kernel.h dependency train with it.
Here is the attempt on cleaning it up by splitting out sprintf() and
friends.
Link: https://lkml.kernel.org/r/20230814163344.17429-1-andriy.shevchenko@linux.intel.com
Link: https://lkml.kernel.org/r/20230814163344.17429-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
switching from a user process to a kernel thread.
- More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
Raghav.
- zsmalloc performance improvements from Sergey Senozhatsky.
- Yue Zhao has found and fixed some data race issues around the
alteration of memcg userspace tunables.
- VFS rationalizations from Christoph Hellwig:
- removal of most of the callers of write_one_page()
- make __filemap_get_folio()'s return value more useful
- Luis Chamberlain has changed tmpfs so it no longer requires swap
backing. Use `mount -o noswap'.
- Qi Zheng has made the slab shrinkers operate locklessly, providing
some scalability benefits.
- Keith Busch has improved dmapool's performance, making part of its
operations O(1) rather than O(n).
- Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
permitting userspace to wr-protect anon memory unpopulated ptes.
- Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
rather than exclusive, and has fixed a bunch of errors which were
caused by its unintuitive meaning.
- Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
which causes minor faults to install a write-protected pte.
- Vlastimil Babka has done some maintenance work on vma_merge():
cleanups to the kernel code and improvements to our userspace test
harness.
- Cleanups to do_fault_around() by Lorenzo Stoakes.
- Mike Rapoport has moved a lot of initialization code out of various
mm/ files and into mm/mm_init.c.
- Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
DRM, but DRM doesn't use it any more.
- Lorenzo has also coverted read_kcore() and vread() to use iterators
and has thereby removed the use of bounce buffers in some cases.
- Lorenzo has also contributed further cleanups of vma_merge().
- Chaitanya Prakash provides some fixes to the mmap selftesting code.
- Matthew Wilcox changes xfs and afs so they no longer take sleeping
locks in ->map_page(), a step towards RCUification of pagefaults.
- Suren Baghdasaryan has improved mmap_lock scalability by switching to
per-VMA locking.
- Frederic Weisbecker has reworked the percpu cache draining so that it
no longer causes latency glitches on cpu isolated workloads.
- Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
logic.
- Liu Shixin has changed zswap's initialization so we no longer waste a
chunk of memory if zswap is not being used.
- Yosry Ahmed has improved the performance of memcg statistics
flushing.
- David Stevens has fixed several issues involving khugepaged,
userfaultfd and shmem.
- Christoph Hellwig has provided some cleanup work to zram's IO-related
code paths.
- David Hildenbrand has fixed up some issues in the selftest code's
testing of our pte state changing.
- Pankaj Raghav has made page_endio() unneeded and has removed it.
- Peter Xu contributed some rationalizations of the userfaultfd
selftests.
- Yosry Ahmed has fixed an issue around memcg's page recalim
accounting.
- Chaitanya Prakash has fixed some arm-related issues in the
selftests/mm code.
- Longlong Xia has improved the way in which KSM handles hwpoisoned
pages.
- Peter Xu fixes a few issues with uffd-wp at fork() time.
- Stefan Roesch has changed KSM so that it may now be used on a
per-process and per-cgroup basis.
* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
shmem: restrict noswap option to initial user namespace
mm/khugepaged: fix conflicting mods to collapse_file()
sparse: remove unnecessary 0 values from rc
mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
maple_tree: fix allocation in mas_sparse_area()
mm: do not increment pgfault stats when page fault handler retries
zsmalloc: allow only one active pool compaction context
selftests/mm: add new selftests for KSM
mm: add new KSM process and sysfs knobs
mm: add new api to enable ksm per process
mm: shrinkers: fix debugfs file permissions
mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
migrate_pages_batch: fix statistics for longterm pin retry
userfaultfd: use helper function range_in_vma()
lib/show_mem.c: use for_each_populated_zone() simplify code
mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
fs/buffer: convert create_page_buffers to folio_create_buffers
fs/buffer: add folio_create_empty_buffers helper
...
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Use isodigit() to test the octal number instead of homegrown approach.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230327142721.48378-1-andriy.shevchenko@linux.intel.com
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%pGp format is used to display 'flags' field of a struct page. However,
some page flags (i.e. PG_buddy, see page-flags.h for more details) are
stored in page_type field. To display human-readable output of page_type,
introduce %pGt format.
It is important to note the meaning of bits are different in page_type.
if page_type is 0xffffffff, no flags are set. Setting PG_buddy
(0x00000080) flag results in a page_type of 0xffffff7f. Clearing a bit
actually means setting a flag. Bits in page_type are inverted when
displaying type names.
Only values for which page_type_has_type() returns true are considered as
page_type, to avoid confusion with mapcount values. if it returns false,
only raw values are displayed and not page type names.
Link: https://lkml.kernel.org/r/20230130042514.2418-3-42.hyeyoo@gmail.com
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com> [vsprintf part]
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/crng/random
Pull random number generator updates from Jason Donenfeld:
- Replace prandom_u32_max() and various open-coded variants of it,
there is now a new family of functions that uses fast rejection
sampling to choose properly uniformly random numbers within an
interval:
get_random_u32_below(ceil) - [0, ceil)
get_random_u32_above(floor) - (floor, U32_MAX]
get_random_u32_inclusive(floor, ceil) - [floor, ceil]
Coccinelle was used to convert all current users of
prandom_u32_max(), as well as many open-coded patterns, resulting in
improvements throughout the tree.
I'll have a "late" 6.1-rc1 pull for you that removes the now unused
prandom_u32_max() function, just in case any other trees add a new
use case of it that needs to converted. According to linux-next,
there may be two trivial cases of prandom_u32_max() reintroductions
that are fixable with a 's/.../.../'. So I'll have for you a final
conversion patch doing that alongside the removal patch during the
second week.
This is a treewide change that touches many files throughout.
- More consistent use of get_random_canary().
- Updates to comments, documentation, tests, headers, and
simplification in configuration.
- The arch_get_random*_early() abstraction was only used by arm64 and
wasn't entirely useful, so this has been replaced by code that works
in all relevant contexts.
- The kernel will use and manage random seeds in non-volatile EFI
variables, refreshing a variable with a fresh seed when the RNG is
initialized. The RNG GUID namespace is then hidden from efivarfs to
prevent accidental leakage.
These changes are split into random.c infrastructure code used in the
EFI subsystem, in this pull request, and related support inside of
EFISTUB, in Ard's EFI tree. These are co-dependent for full
functionality, but the order of merging doesn't matter.
- Part of the infrastructure added for the EFI support is also used for
an improvement to the way vsprintf initializes its siphash key,
replacing an sleep loop wart.
- The hardware RNG framework now always calls its correct random.c
input function, add_hwgenerator_randomness(), rather than sometimes
going through helpers better suited for other cases.
- The add_latent_entropy() function has long been called from the fork
handler, but is a no-op when the latent entropy gcc plugin isn't
used, which is fine for the purposes of latent entropy.
But it was missing out on the cycle counter that was also being mixed
in beside the latent entropy variable. So now, if the latent entropy
gcc plugin isn't enabled, add_latent_entropy() will expand to a call
to add_device_randomness(NULL, 0), which adds a cycle counter,
without the absent latent entropy variable.
- The RNG is now reseeded from a delayed worker, rather than on demand
when used. Always running from a worker allows it to make use of the
CPU RNG on platforms like S390x, whose instructions are too slow to
do so from interrupts. It also has the effect of adding in new inputs
more frequently with more regularity, amounting to a long term
transcript of random values. Plus, it helps a bit with the upcoming
vDSO implementation (which isn't yet ready for 6.2).
- The jitter entropy algorithm now tries to execute on many different
CPUs, round-robining, in hopes of hitting even more memory latencies
and other unpredictable effects. It also will mix in a cycle counter
when the entropy timer fires, in addition to being mixed in from the
main loop, to account more explicitly for fluctuations in that timer
firing. And the state it touches is now kept within the same cache
line, so that it's assured that the different execution contexts will
cause latencies.
* tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits)
random: include <linux/once.h> in the right header
random: align entropy_timer_state to cache line
random: mix in cycle counter when jitter timer fires
random: spread out jitter callback to different CPUs
random: remove extraneous period and add a missing one in comments
efi: random: refresh non-volatile random seed when RNG is initialized
vsprintf: initialize siphash key using notifier
random: add back async readiness notifier
random: reseed in delayed work rather than on-demand
random: always mix cycle counter in add_latent_entropy()
hw_random: use add_hwgenerator_randomness() for early entropy
random: modernize documentation comment on get_random_bytes()
random: adjust comment to account for removed function
random: remove early archrandom abstraction
random: use random.trust_{bootloader,cpu} command line option only
stackprotector: actually use get_random_canary()
stackprotector: move get_random_canary() into stackprotector.h
treewide: use get_random_u32_inclusive() when possible
treewide: use get_random_u32_{above,below}() instead of manual loop
treewide: use get_random_u32_below() instead of deprecated function
...
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Rather than polling every second, use the new notifier to do this at
exactly the right moment.
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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Replace the obsolete and ambiguos macro in_irq() with new
macro in_hardirq().
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221011024831.322799-1-ye.xingchen@zte.com.cn
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git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Initialize pointer hashing using the system workqueue. It avoids
taking locks in printk()/vsprintf() code path
- Misc code clean up
* tag 'printk-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: Mark __printk percpu data ready __ro_after_init
printk: Remove bogus comment vs. boot consoles
printk: Remove write only variable nr_ext_console_drivers
printk: Declare log_wait properly
printk: Make pr_flush() static
lib/vsprintf: Initialize vsprintf's pointer hash once the random core is ready.
lib/vsprintf: Remove static_branch_likely() from __ptr_to_hashval().
lib/vnsprintf: add const modifier for param 'bitmap'
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The printk code invokes vnsprintf in order to compute the complete
string before adding it into its buffer. This happens in an IRQ-off
region which leads to a warning on PREEMPT_RT in the random code if the
format strings contains a %p for pointer printing. This happens because
the random core acquires locks which become sleeping locks on PREEMPT_RT
which must not be acquired with disabled interrupts and or preemption
disabled.
By default the pointers are hashed which requires a random value on the
first invocation (either by printk or another user which comes first.
One could argue that there is no need for printk to disable interrupts
during the vsprintf() invocation which would fix the just mentioned
problem. However printk itself can be invoked in a context with
disabled interrupts which would lead to the very same problem.
Move the initialization of ptr_key into a worker and schedule it from
subsys_initcall(). This happens early but after the workqueue subsystem
is ready. Use get_random_bytes() to retrieve the random value if the RNG
core is ready, otherwise schedule a worker in two seconds and try again.
Another advantage is that it removes a lock from the vsprintf() code path.
It prevents a possible deadlock when printk("%p", ptr) is called under
the lock taken in get_random_bytes().
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
[pmladek@suse.com: Added a note about the it prevented a possible deadlock in printk().]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220927104912.622645-3-bigeasy@linutronix.de
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Using static_branch_likely() to signal that ptr_key has been filled is a
bit much given that it is not a fast path.
Replace static_branch_likely() with bool for condition and a memory
barrier for ptr_key.
Suggested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220927104912.622645-2-bigeasy@linutronix.de
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This patch adds a format specifier `%pA` to `vsprintf` which formats
a pointer as `core::fmt::Arguments`. Doing so allows us to directly
format to the internal buffer of `printf`, so we do not have to use
a temporary buffer on the stack to pre-assemble the message on
the Rust side.
This specifier is intended only to be used from Rust and not for C, so
`checkpatch.pl` is intentionally unchanged to catch any misuse.
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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There is no modification for param bitmap in function
bitmap_string() and bitmap_list_string(), so add const
modifier for it.
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220816144557.30779-1-huangguangbin2@huawei.com
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With arch randomness being used by every distro and enabled in
defconfigs, the distinction between rng_has_arch_random() and
rng_is_initialized() is now rather small. In fact, the places where they
differ are now places where paranoid users and system builders really
don't want arch randomness to be used, in which case we should respect
that choice, or places where arch randomness is known to be broken, in
which case that choice is all the more important. So this commit just
removes the function and its one user.
Reviewed-by: Petr Mladek <pmladek@suse.com> # for vsprintf.c
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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The register_random_ready_notifier() notifier is somewhat complicated,
and was already recently rewritten to use notifier blocks. It is only
used now by one consumer in the kernel, vsprintf.c, for which the async
mechanism is really overly complex for what it actually needs. This
commit removes register_random_ready_notifier() and unregister_random_
ready_notifier(), because it just adds complication with little utility,
and changes vsprintf.c to just check on `!rng_is_initialized() &&
!rng_has_arch_random()`, which will eventually be true. Performance-
wise, that code was already using a static branch, so there's basically
no overhead at all to this change.
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Petr Mladek <pmladek@suse.com> # for vsprintf.c
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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The RNG incorporates RDRAND into its state at boot and every time it
reseeds, so there's no reason for callers to use it directly. The
hashing that the RNG does on it is preferable to using the bytes raw.
The only current use case of get_random_bytes_arch() is vsprintf's
siphash key for pointer hashing, which uses it to initialize the pointer
secret earlier than usual if RDRAND is available. In order to replace
this narrow use case, just expose whether RDRAND is mixed into the RNG,
with a new function called rng_has_arch_random(). With that taken care
of, there are no users of get_random_bytes_arch() left, so it can be
removed.
Later, if trust_cpu gets turned on by default (as most distros are
doing), this one use of rng_has_arch_random() can probably go away as
well.
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Petr Mladek <pmladek@suse.com> # for vsprintf.c
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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Patch series "mm/page_owner: Extend page_owner to show memcg information", v4.
While debugging the constant increase in percpu memory consumption on a
system that spawned large number of containers, it was found that a lot
of offline mem_cgroup structures remained in place without being freed.
Further investigation indicated that those mem_cgroup structures were
pinned by some pages.
In order to find out what those pages are, the existing page_owner
debugging tool is extended to show memory cgroup information and whether
those memcgs are offline or not. With the enhanced page_owner tool, the
following is a typical page that pinned the mem_cgroup structure in my
test case:
Page allocated via order 0, mask 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 162970 (podman), ts 1097761405537 ns, free_ts 1097760838089 ns
PFN 1925700 type Movable Block 3761 type Movable Flags 0x17ffffc00c001c(uptodate|dirty|lru|reclaim|swapbacked|node=0|zone=2|lastcpupid=0x1fffff)
prep_new_page+0xac/0xe0
get_page_from_freelist+0x1327/0x14d0
__alloc_pages+0x191/0x340
alloc_pages_vma+0x84/0x250
shmem_alloc_page+0x3f/0x90
shmem_alloc_and_acct_page+0x76/0x1c0
shmem_getpage_gfp+0x281/0x940
shmem_write_begin+0x36/0xe0
generic_perform_write+0xed/0x1d0
__generic_file_write_iter+0xdc/0x1b0
generic_file_write_iter+0x5d/0xb0
new_sync_write+0x11f/0x1b0
vfs_write+0x1ba/0x2a0
ksys_write+0x59/0xd0
do_syscall_64+0x37/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
Charged to offline memcg libpod-conmon-15e4f9c758422306b73b2dd99f9d50a5ea53cbb16b4a13a2c2308a4253cc0ec8.
So the page was not freed because it was part of a shmem segment. That
is useful information that can help users to diagnose similar problems.
With cgroup v1, /proc/cgroups can be read to find out the total number
of memory cgroups (online + offline). With cgroup v2, the cgroup.stat
of the root cgroup can be read to find the number of dying cgroups (most
likely pinned by dying memcgs).
The page_owner feature is not supposed to be enabled for production
system due to its memory overhead. However, if it is suspected that
dying memcgs are increasing over time, a test environment with
page_owner enabled can then be set up with appropriate workload for
further analysis on what may be causing the increasing number of dying
memcgs.
This patch (of 4):
For *scnprintf(), vsnprintf() is always called even if the input size is
0. That is a waste of time, so just return 0 in this case.
Note that vsnprintf() will never return -1 to indicate an error. So
skipping the call to vsnprintf() when size is 0 will have no functional
impact at all.
Link: https://lkml.kernel.org/r/20220202203036.744010-1-longman@redhat.com
Link: https://lkml.kernel.org/r/20220202203036.744010-2-longman@redhat.com
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Make %pK behave the same as %p for kptr_restrict == 0 also with
no_hash_pointers parameter
- Ignore the default console in the device tree also when console=null
or console="" is used on the command line
- Document console=null and console="" behavior
- Prevent a deadlock and a livelock caused by console_lock in panic()
- Make console_lock available for panicking CPU
- Fast query for the next to-be-used sequence number
- Use the expected return values in printk.devkmsg __setup handler
- Use the correct atomic operations in wake_up_klogd() irq_work handler
- Avoid possible unaligned access when handling %4cc printing format
* tag 'printk-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: fix return value of printk.devkmsg __setup handler
vsprintf: Fix %pK with kptr_restrict == 0
printk: make suppress_panic_printk static
printk: Set console_set_on_cmdline=1 when __add_preferred_console() is called with user_specified == true
Docs: printk: add 'console=null|""' to admin/kernel-parameters
printk: use atomic updates for klogd work
printk: Drop console_sem during panic
printk: Avoid livelock with heavy printk during panic
printk: disable optimistic spin during panic
printk: Add panic_in_progress helper
vsprintf: Move space out of string literals in fourcc_string()
vsprintf: Fix potential unaligned access
printk: ringbuffer: Improve prb_next_seq() performance
|
|
|
|
We previously rolled our own randomness readiness notifier, which only
has two users in the whole kernel. Replace this with a more standard
atomic notifier block that serves the same purpose with less code. Also
unexport the symbols, because no modules use it, only unconditional
builtins. The only drawback is that it's possible for a notification
handler returning the "stop" code to prevent further processing, but
given that there are only two users, and that we're unexporting this
anyway, that doesn't seem like a significant drawback for the
simplification we receive here.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
|
|
Although kptr_restrict is set to 0 and the kernel is booted with
no_hash_pointers parameter, the content of /proc/vmallocinfo is
lacking the real addresses.
/ # cat /proc/vmallocinfo
0x(ptrval)-0x(ptrval) 8192 load_module+0xc0c/0x2c0c pages=1 vmalloc
0x(ptrval)-0x(ptrval) 12288 start_kernel+0x4e0/0x690 pages=2 vmalloc
0x(ptrval)-0x(ptrval) 12288 start_kernel+0x4e0/0x690 pages=2 vmalloc
0x(ptrval)-0x(ptrval) 8192 _mpic_map_mmio.constprop.0+0x20/0x44 phys=0x80041000 ioremap
0x(ptrval)-0x(ptrval) 12288 _mpic_map_mmio.constprop.0+0x20/0x44 phys=0x80041000 ioremap
...
According to the documentation for /proc/sys/kernel/, %pK is
equivalent to %p when kptr_restrict is set to 0.
Fixes: 5ead723a20e0 ("lib/vsprintf: no_hash_pointers prints all addresses as unhashed")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/107476128e59bff11a309b5bf7579a1753a41aca.1645087605.git.christophe.leroy@csgroup.eu
|
|
The literals "big-endian" and "little-endian" may be potentially
occurred in other places. Dropping space allows linker to
merge them by using only a single copy.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220127181233.72910-2-andriy.shevchenko@linux.intel.com
|
|
The %p4cc specifier in some cases might get an unaligned pointer.
Due to this we need to make copy to local variable once to avoid
potential crashes on some architectures due to improper access.
Fixes: af612e43de6d ("lib/vsprintf: Add support for printing V4L2 and DRM fourccs")
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220127181233.72910-1-andriy.shevchenko@linux.intel.com
|
|
Pull bitmap updates from Yury Norov:
- introduce for_each_set_bitrange()
- use find_first_*_bit() instead of find_next_*_bit() where possible
- unify for_each_bit() macros
* tag 'bitmap-5.17-rc1' of git://github.com/norov/linux:
vsprintf: rework bitmap_list_string
lib: bitmap: add performance test for bitmap_print_to_pagebuf
bitmap: unify find_bit operations
mm/percpu: micro-optimize pcpu_is_populated()
Replace for_each_*_bit_from() with for_each_*_bit() where appropriate
find: micro-optimize for_each_{set,clear}_bit()
include/linux: move for_each_bit() macros from bitops.h to find.h
cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
tools: sync tools/bitmap with mother linux
all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate
cpumask: use find_first_and_bit()
lib: add find_first_and_bit()
arch: remove GENERIC_FIND_FIRST_BIT entirely
include: move find.h from asm_generic to linux
bitops: move find_bit_*_le functions from le.h to find.h
bitops: protect find_first_{,zero}_bit properly
|
|
bitmap_list_string() is very ineffective when printing bitmaps with long
ranges of set bits because it calls find_next_bit for each bit in the
bitmap. We can do better by detecting ranges of set bits.
In my environment, before/after is 943008/31008 ns.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
|
|
The 'set' bitmap is local to this function. No concurrent access to it is
possible.
So prefer the non-atomic '__[set|clear]_bit()' function to save a few
cycles.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/1abf81a5e509d372393bd22041eed4ebc07ef9f7.1638023178.git.christophe.jaillet@wanadoo.fr
|
|
Merge more updates from Andrew Morton:
"87 patches.
Subsystems affected by this patch series: mm (pagecache and hugetlb),
procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
sysvfs, kcov, gdb, resource, selftests, and ipc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
selftests/kselftest/runner/run_one(): allow running non-executable files
virtio-mem: disallow mapping virtio-mem memory via /dev/mem
kernel/resource: disallow access to exclusive system RAM regions
kernel/resource: clean up and optimize iomem_is_exclusive()
scripts/gdb: handle split debug for vmlinux
kcov: replace local_irq_save() with a local_lock_t
kcov: avoid enable+disable interrupts if !in_task()
kcov: allocate per-CPU memory on the relevant node
Documentation/kcov: define `ip' in the example
Documentation/kcov: include types.h in the example
sysv: use BUILD_BUG_ON instead of runtime check
kernel/fork.c: unshare(): use swap() to make code cleaner
seq_file: fix passing wrong private data
seq_file: move seq_escape() to a header
signal: remove duplicate include in signal.h
crash_dump: remove duplicate include in crash_dump.h
crash_dump: fix boolreturn.cocci warning
hfs/hfsplus: use WARN_ON for sanity check
...
|
|
Codegen become bloated again after simple_strntoull() introduction
add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-224 (-224)
Function old new delta
simple_strtoul 5 2 -3
simple_strtol 23 20 -3
simple_strtoull 119 15 -104
simple_strtoll 155 41 -114
Link: https://lkml.kernel.org/r/YVmlB9yY4lvbNKYt@localhost.localdomain
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
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|
|
There are couple of improvements to static asserts against
the format specifier flags:
- new static assert for SIGN
- fix static assert for SMALL
SMALL is not equal to ASCII code of white space, it equals to
the bit difference between capital and small letters (however
the value is the same, semantically expression means different
things).
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20211026140356.45610-1-andriy.shevchenko@linux.intel.com
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|
All existing users of %pGp want the hex value as well as the decoded
flag names. This looks awkward (passing the same parameter to printf
twice), so move that functionality into the core. If we want, we
can make that optional with flag arguments to %pGp in the future.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20211019142621.2810043-6-willy@infradead.org
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Merge more updates from Andrew Morton:
"147 patches, based on 7d2a07b769330c34b4deabeed939325c77a7ec2f.
Subsystems affected by this patch series: mm (memory-hotplug, rmap,
ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
selftests, ipc, and scripts"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
scripts: check_extable: fix typo in user error message
mm/workingset: correct kernel-doc notations
ipc: replace costly bailout check in sysvipc_find_ipc()
selftests/memfd: remove unused variable
Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
configs: remove the obsolete CONFIG_INPUT_POLLDEV
prctl: allow to setup brk for et_dyn executables
pid: cleanup the stale comment mentioning pidmap_init().
kernel/fork.c: unexport get_{mm,task}_exe_file
coredump: fix memleak in dump_vma_snapshot()
fs/coredump.c: log if a core dump is aborted due to changed file permissions
nilfs2: use refcount_dec_and_lock() to fix potential UAF
nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
nilfs2: fix NULL pointer in nilfs_##name##_attr_release
nilfs2: fix memory leak in nilfs_sysfs_create_device_group
trap: cleanup trap_init()
init: move usermodehelper_enable() to populate_rootfs()
...
|
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Instead of hard-coding ((1UL << NR_PAGEFLAGS) - 1) everywhere, introducing
PAGEFLAGS_MASK to make the code clear to get the page flags.
Link: https://lkml.kernel.org/r/20210819150712.59948-1-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ship minimal stdarg.h (1 type, 4 macros) as <linux/stdarg.h>.
stdarg.h is the only userspace header commonly used in the kernel.
GPL 2 version of <stdarg.h> can be extracted from
http://archive.debian.org/debian/pool/main/g/gcc-4.2/gcc-4.2_4.2.4.orig.tar.gz
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
|
|
Let's make kernel stacktraces easier to identify by including the build
ID[1] of a module if the stacktrace is printing a symbol from a module.
This makes it simpler for developers to locate a kernel module's full
debuginfo for a particular stacktrace. Combined with
scripts/decode_stracktrace.sh, a developer can download the matching
debuginfo from a debuginfod[2] server and find the exact file and line
number for the functions plus offsets in a stacktrace that match the
module. This is especially useful for pstore crash debugging where the
kernel crashes are recorded in something like console-ramoops and the
recovery kernel/modules are different or the debuginfo doesn't exist on
the device due to space concerns (the debuginfo can be too large for space
limited devices).
Originally, I put this on the %pS format, but that was quickly rejected
given that %pS is used in other places such as ftrace where build IDs
aren't meaningful. There was some discussions on the list to put every
module build ID into the "Modules linked in:" section of the stacktrace
message but that quickly becomes very hard to read once you have more than
three or four modules linked in. It also provides too much information
when we don't expect each module to be traversed in a stacktrace. Having
the build ID for modules that aren't important just makes things messy.
Splitting it to multiple lines for each module quickly explodes the number
of lines printed in an oops too, possibly wrapping the warning off the
console. And finally, trying to stash away each module used in a
callstack to provide the ID of each symbol printed is cumbersome and would
require changes to each architecture to stash away modules and return
their build IDs once unwinding has completed.
Instead, we opt for the simpler approach of introducing new printk formats
'%pS[R]b' for "pointer symbolic backtrace with module build ID" and '%pBb'
for "pointer backtrace with module build ID" and then updating the few
places in the architecture layer where the stacktrace is printed to use
this new format.
Before:
Call trace:
lkdtm_WARNING+0x28/0x30 [lkdtm]
direct_entry+0x16c/0x1b4 [lkdtm]
full_proxy_write+0x74/0xa4
vfs_write+0xec/0x2e8
After:
Call trace:
lkdtm_WARNING+0x28/0x30 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9]
direct_entry+0x16c/0x1b4 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9]
full_proxy_write+0x74/0xa4
vfs_write+0xec/0x2e8
[akpm@linux-foundation.org: fix build with CONFIG_MODULES=n, tweak code layout]
[rdunlap@infradead.org: fix build when CONFIG_MODULES is not set]
Link: https://lkml.kernel.org/r/20210513171510.20328-1-rdunlap@infradead.org
[akpm@linux-foundation.org: make kallsyms_lookup_buildid() static]
[cuibixuan@huawei.com: fix build error when CONFIG_SYSFS is disabled]
Link: https://lkml.kernel.org/r/20210525105049.34804-1-cuibixuan@huawei.com
Link: https://lkml.kernel.org/r/20210511003845.2429846-6-swboyd@chromium.org
Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1]
Link: https://sourceware.org/elfutils/Debuginfod.html [2]
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
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Fix some spelling mistakes in comments:
permanentely ==> permanently
wont ==> won't
remaning ==> remaining
succed ==> succeed
shouldnt ==> shouldn't
alpha-numeric ==> alphanumeric
storeing ==> storing
funtion ==> function
documenation ==> documentation
Determin ==> Determine
intepreted ==> interpreted
ammount ==> amount
obious ==> obvious
interupts ==> interrupts
occured ==> occurred
asssociated ==> associated
taking into acount ==> taking into account
squence ==> sequence
stil ==> still
contiguos ==> contiguous
matchs ==> matches
Link: https://lkml.kernel.org/r/20210607072555.12416-1-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
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Merge more updates from Andrew Morton:
"190 patches.
Subsystems affected by this patch series: mm (hugetlb, userfaultfd,
vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock,
migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap,
zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc,
core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs,
signals, exec, kcov, selftests, compress/decompress, and ipc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits)
ipc/util.c: use binary search for max_idx
ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock
ipc: use kmalloc for msg_queue and shmid_kernel
ipc sem: use kvmalloc for sem_undo allocation
lib/decompressors: remove set but not used variabled 'level'
selftests/vm/pkeys: exercise x86 XSAVE init state
selftests/vm/pkeys: refill shadow register after implicit kernel write
selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
kcov: add __no_sanitize_coverage to fix noinstr for all architectures
exec: remove checks in __register_bimfmt()
x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned
hfsplus: report create_date to kstat.btime
hfsplus: remove unnecessary oom message
nilfs2: remove redundant continue statement in a while-loop
kprobes: remove duplicated strong free_insn_page in x86 and s390
init: print out unknown kernel parameters
checkpatch: do not complain about positive return values starting with EPOLL
checkpatch: improve the indented label test
checkpatch: scripts/spdxcheck.py now requires python3
...
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Gcc inlines simple_strtoull() too agressively.
Given that all 4 signatures match, everything very efficiently calls or
tailcalls into simple_strtoull():
ffffffff81da0240 <simple_strtoll>:
ffffffff81da0240: 80 3f 2d cmp BYTE PTR [rdi],0x2d
ffffffff81da0243: 74 05 je ffffffff81da024a <simple_strtoll+0xa>
ffffffff81da0245: e9 76 ff ff ff jmp simple_strtoull
ffffffff81da024a: 48 83 c7 01 add rdi,0x1
ffffffff81da024e: e8 6d ff ff ff call simple_strtoull
ffffffff81da0253: 48 f7 d8 neg rax
ffffffff81da0256: c3 ret
Space savings (on F34-ish .config)
add/remove: 0/0 grow/shrink: 1/3 up/down: 52/-313 (-261)
Function old new delta
vsscanf 2167 2219 +52
simple_strtoul 72 2 -70
simple_strtoll 143 23 -120
simple_strtol 143 20 -123
Link: https://lkml.kernel.org/r/YMO2zoOQk2eF34tn@localhost.localdomain
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge misc updates from Andrew Morton:
"191 patches.
Subsystems affected by this patch series: kthread, ia64, scripts,
ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
pagealloc, and memory-failure)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
mm,hwpoison: make get_hwpoison_page() call get_any_page()
mm,hwpoison: send SIGBUS with error virutal address
mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
docs: remove description of DISCONTIGMEM
arch, mm: remove stale mentions of DISCONIGMEM
mm: remove CONFIG_DISCONTIGMEM
m68k: remove support for DISCONTIGMEM
arc: remove support for DISCONTIGMEM
arc: update comment about HIGHMEM implementation
alpha: remove DISCONTIGMEM and NUMA
mm/page_alloc: move free_the_page
mm/page_alloc: fix counting of managed_pages
mm/page_alloc: improve memmap_pages dbg msg
mm: drop SECTION_SHIFT in code comments
mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
mm/page_alloc: scale the number of pages that are batch freed
...
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git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Add %pt[RT]s modifier to vsprintf(). It overrides ISO 8601 separator
by using ' ' (space). It produces "YYYY-mm-dd HH:MM:SS" instead of
"YYYY-mm-ddTHH:MM:SS".
- Correctly parse long row of numbers by sscanf() when using the field
width. Add extensive sscanf() selftest.
- Generalize re-entrant CPU lock that has already been used to
serialize dump_stack() output. It is part of the ongoing printk
rework. It will allow to remove the obsoleted printk_safe buffers and
introduce atomic consoles.
- Some code clean up and sparse warning fixes.
* tag 'printk-for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: fix cpu lock ordering
lib/dump_stack: move cpu lock to printk.c
printk: Remove trailing semicolon in macros
random32: Fix implicit truncation warning in prandom_seed_state()
lib: test_scanf: Remove pointless use of type_min() with unsigned types
selftests: lib: Add wrapper script for test_scanf
lib: test_scanf: Add tests for sscanf number conversion
lib: vsprintf: Fix handling of number field widths in vsscanf
lib: vsprintf: scanf: Negative number must have field width > 1
usb: host: xhci-tegra: Switch to use %ptTs
nilfs2: Switch to use %ptTs
kdb: Switch to use %ptTs
lib/vsprintf: Allow to override ISO 8601 date and time separator
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Obscuring the pointers that slub shows when debugging makes for some
confusing slub debug messages:
Padding overwritten. 0x0000000079f0674a-0x000000000d4dce17
Those addresses are hashed for kernel security reasons. If we're trying
to be secure with slub_debug on the commandline we have some big problems
given that we dump whole chunks of kernel memory to the kernel logs.
Let's force on the no_hash_pointers commandline flag when slub_debug is on
the commandline. This makes slub debug messages more meaningful and if by
chance a kernel address is in some slub debug object dump we will have a
better chance of figuring out what went wrong.
Note that we don't use %px in the slub code because we want to reduce the
number of places that %px is used in the kernel. This also nicely prints
a big fat warning at kernel boot if slub_debug is on the commandline so
that we know that this kernel shouldn't be used on production systems.
[akpm@linux-foundation.org: fix build with CONFIG_SLUB_DEBUG=n]
Link: https://lkml.kernel.org/r/20210601182202.3011020-5-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Petr Mladek <pmladek@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The existing code attempted to handle numbers by doing a strto[u]l(),
ignoring the field width, and then repeatedly dividing to extract the
field out of the full converted value. If the string contains a run of
valid digits longer than will fit in a long or long long, this would
overflow and no amount of dividing can recover the correct value.
This patch fixes vsscanf() to obey number field widths when parsing
the number.
A new _parse_integer_limit() is added that takes a limit for the number
of characters to parse. The number field conversion in vsscanf is changed
to use this new function.
If a number starts with a radix prefix, the field width must be long
enough for at last one digit after the prefix. If not, it will be handled
like this:
sscanf("0x4", "%1i", &i): i=0, scanning continues with the 'x'
sscanf("0x4", "%2i", &i): i=0, scanning continues with the '4'
This is consistent with the observed behaviour of userland sscanf.
Note that this patch does NOT fix the problem of a single field value
overflowing the target type. So for example:
sscanf("123456789abcdef", "%x", &i);
Will not produce the correct result because the value obviously overflows
INT_MAX. But sscanf will report a successful conversion.
Note that where a very large number is used to mean "unlimited", the value
INT_MAX is used for consistency with the behaviour of vsnprintf().
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210514161206.30821-2-rf@opensource.cirrus.com
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If a signed number field starts with a '-' the field width must be > 1,
or unlimited, to allow at least one digit after the '-'.
This patch adds a check for this. If a signed field starts with '-'
and field_width == 1 the scanf will quit.
It is ok for a signed number field to have a field width of 1 if it
starts with a digit. In that case the single digit can be converted.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210514161206.30821-1-rf@opensource.cirrus.com
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