PCI: Move pci_iomap.c to drivers/pci/

The entirety of pci_iomap.c is guarded by an #ifdef CONFIG_PCI. It,
consequently, does not belong to lib/ because it is not generic
infrastructure.

Move pci_io

PCI: Move pci_iomap.c to drivers/pci/

The entirety of pci_iomap.c is guarded by an #ifdef CONFIG_PCI. It,
consequently, does not belong to lib/ because it is not generic
infrastructure.

Move pci_iomap.c to drivers/pci/ and implement the necessary changes to
Makefiles and Kconfigs.

Update MAINTAINERS file.

Update Documentation.

Link: https://lore.kernel.org/r/20240131090023.12331-3-pstanner@redhat.com
[bhelgaas: squash in https://lore.kernel.org/r/20240212150934.24559-1-pstanner@redhat.com]
Suggested-by: Danilo Krummrich <dakr@redhat.com>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

show more ...

lib/stackdepot: use fixed-sized slots for stack records

Instead of storing stack records in stack depot pools one right after
another, use fixed-sized slots.

Add a new Kconfig option STACKDEPOT_MAX

lib/stackdepot: use fixed-sized slots for stack records

Instead of storing stack records in stack depot pools one right after
another, use fixed-sized slots.

Add a new Kconfig option STACKDEPOT_MAX_FRAMES that allows to select the
size of the slot in frames. Use 64 as the default value, which is the
maximum stack trace size both KASAN and KMSAN use right now.

Also add descriptions for other stack depot Kconfig options.

This is preparatory patch for implementing the eviction of stack records
from the stack depot.

Link: https://lkml.kernel.org/r/dce7d030a99ff61022509665187fac45b0827298.1700502145.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

acpi: Move common tables helper functions to common lib

Some of the routines in ACPI driver/acpi/tables.c can be shared with
parsing CDAT. CDAT is a device-provided data structure that is formatted

acpi: Move common tables helper functions to common lib

Some of the routines in ACPI driver/acpi/tables.c can be shared with
parsing CDAT. CDAT is a device-provided data structure that is formatted
similar to a platform provided ACPI table. CDAT is used by CXL and can
exist on platforms that do not use ACPI. Split out the common routine
from ACPI to accommodate platforms that do not support ACPI and move that
to /lib. The common routines can be built outside of ACPI if
FIRMWARE_TABLES is selected.

Link: https://lore.kernel.org/linux-cxl/CAJZ5v0jipbtTNnsA0-o5ozOk8ZgWnOg34m34a9pPenTyRLj=6A@mail.gmail.com/
Suggested-by: "Rafael J. Wysocki" <rafael@kernel.org>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/169713683430.2205276.17899451119920103445.stgit@djiang5-mobl3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

bcache: move closures to lib/

Prep work for bcachefs - being a fork of bcache it also uses closures

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Acked-by: Coly Li <colyli@suse.de>
Rev

bcache: move closures to lib/

Prep work for bcachefs - being a fork of bcache it also uses closures

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>

show more ...

lib: add light-weight queuing mechanism.

lwq is a FIFO single-linked queue that only requires a spinlock
for dequeueing, which happens in process context. Enqueueing is atomic
with no spinlock and

lib: add light-weight queuing mechanism.

lwq is a FIFO single-linked queue that only requires a spinlock
for dequeueing, which happens in process context. Enqueueing is atomic
with no spinlock and can happen in any context.

This is particularly useful when work items are queued from BH or IRQ
context, and when they are handled one at a time by dedicated threads.

Avoiding any locking when enqueueing means there is no need to disable
BH or interrupts, which is generally best avoided (particularly when
there are any RT tasks on the machine).

This solution is superior to using "list_head" links because we need
half as many pointers in the data structures, and because list_head
lists would need locking to add items to the queue.

This solution is superior to a bespoke solution as all locking and
container_of casting is integrated, so the interface is simple.

Despite the similar name, this solution meets a distinctly different
need to kfifo. kfifo provides a fixed sized circular buffer to which
data can be added at one end and removed at the other, and does not
provide any locking. lwq does not have any size limit and works with
data structures (objects?) rather than data (bytes).

A unit test for basic functionality, which runs at boot time, is included.

Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Gow <davidgow@google.com>
Cc: linux-kernel@vger.kernel.org
Message-Id: <20230911111333.4d1a872330e924a00acb905b@linux-foundation.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

show more ...

lib/bch.c: use bitrev instead of internal logic

Replace internal logic with separate bitrev library.

Link: https://lkml.kernel.org/r/20230730081717.1498217-1-sanpeqf@gmail.com
Signed-off-by: John S

lib/bch.c: use bitrev instead of internal logic

Replace internal logic with separate bitrev library.

Link: https://lkml.kernel.org/r/20230730081717.1498217-1-sanpeqf@gmail.com
Signed-off-by: John Sanpe <sanpeqf@gmail.com>
Cc: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

Kconfig: introduce HAS_IOPORT option and select it as necessary

We introduce a new HAS_IOPORT Kconfig option to indicate support for I/O
Port access. In a future patch HAS_IOPORT=n will disable comp

Kconfig: introduce HAS_IOPORT option and select it as necessary

We introduce a new HAS_IOPORT Kconfig option to indicate support for I/O
Port access. In a future patch HAS_IOPORT=n will disable compilation of
the I/O accessor functions inb()/outb() and friends on architectures
which can not meaningfully support legacy I/O spaces such as s390.

The following architectures do not select HAS_IOPORT:

* ARC
* C-SKY
* Hexagon
* Nios II
* OpenRISC
* s390
* User-Mode Linux
* Xtensa

All other architectures select HAS_IOPORT at least conditionally.

The "depends on" relations on HAS_IOPORT in drivers as well as ifdefs
for HAS_IOPORT specific sections will be added in subsequent patches on
a per subsystem basis.

Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net> # for ARCH=um
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

show more ...

lib: packing: replace bit_reverse() with bitrev8()

Remove bit_reverse() function. Instead use bitrev8() from linux/bitrev.h +
bitshift. Reduces code-repetition.

Signed-off-by: Uladzislau Koshchan

lib: packing: replace bit_reverse() with bitrev8()

Remove bit_reverse() function. Instead use bitrev8() from linux/bitrev.h +
bitshift. Reduces code-repetition.

Signed-off-by: Uladzislau Koshchanka <koshchanka@gmail.com>
Link: https://lore.kernel.org/r/20221210004423.32332-1-koshchanka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

show more ...

cpumask: limit visibility of FORCE_NR_CPUS

In current form, FORCE_NR_CPUS is visible to all users building their
kernels, even not experts. It is also set in allmodconfig or
allyesconfig, which is

cpumask: limit visibility of FORCE_NR_CPUS

In current form, FORCE_NR_CPUS is visible to all users building their
kernels, even not experts. It is also set in allmodconfig or
allyesconfig, which is not a correct behavior.

This patch fixes it. It also changes the parameter short description:
removes implementation details and highlights the effect of the change.

Link: https://lkml.kernel.org/r/20221116172451.274938-1-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sander Vanheule <sander@svanheule.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

interval-tree: Add a utility to iterate over spans in an interval tree

The span iterator travels over the indexes of the interval_tree, not the
nodes, and classifies spans of indexes as either 'used

interval-tree: Add a utility to iterate over spans in an interval tree

The span iterator travels over the indexes of the interval_tree, not the
nodes, and classifies spans of indexes as either 'used' or 'hole'.

'used' spans are fully covered by nodes in the tree and 'hole' spans have
no node intersecting the span.

This is done greedily such that spans are maximally sized and every
iteration step switches between used/hole.

As an example a trivial allocator can be written as:

for (interval_tree_span_iter_first(&span, itree, 0, ULONG_MAX);
!interval_tree_span_iter_done(&span);
interval_tree_span_iter_next(&span))
if (span.is_hole &&
span.last_hole - span.start_hole >= allocation_size - 1)
return span.start_hole;

With all the tricky boundary conditions handled by the library code.

The following iommufd patches have several algorithms for its overlapping
node interval trees that are significantly simplified with this kind of
iteration primitive. As it seems generally useful, put it into lib/.

Link: https://lore.kernel.org/r/3-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

show more ...

memregion: Add cpu_cache_invalidate_memregion() interface

With CXL security features, and CXL dynamic provisioning, global CPU
cache flushing nvdimm requirements are no longer specific to that
subsy

memregion: Add cpu_cache_invalidate_memregion() interface

With CXL security features, and CXL dynamic provisioning, global CPU
cache flushing nvdimm requirements are no longer specific to that
subsystem, even beyond the scope of security_ops. CXL will need such
semantics for features not necessarily limited to persistent memory.

The functionality this is enabling is to be able to instantaneously
secure erase potentially terabytes of memory at once and the kernel
needs to be sure that none of the data from before the erase is still
present in the cache. It is also used when unlocking a memory device
where speculative reads and firmware accesses could have cached poison
from before the device was unlocked. Lastly this facility is used when
mapping new devices, or new capacity into an established physical
address range. I.e. when the driver switches DeviceA mapping AddressX to
DeviceB mapping AddressX then any cached data from DeviceA:AddressX
needs to be invalidated.

This capability is typically only used once per-boot (for unlock), or
once per bare metal provisioning event (secure erase), like when handing
off the system to another tenant or decommissioning a device. It may
also be used for dynamic CXL region provisioning.

Users must first call cpu_cache_has_invalidate_memregion() to know
whether this functionality is available on the architecture. On x86 this
respects the constraints of when wbinvd() is tolerable. It is already
the case that wbinvd() is problematic to allow in VMs due its global
performance impact and KVM, for example, has been known to just trap and
ignore the call. With confidential computing guest execution of wbinvd()
may even trigger an exception. Given guests should not be messing with
the bare metal address map via CXL configuration changes
cpu_cache_has_invalidate_memregion() returns false in VMs.

While this global cache invalidation facility, is exported to modules,
since NVDIMM and CXL support can be built as a module, it is not for
general use. The intent is that this facility is not available outside
of specific "device-memory" use cases. To make that expectation as clear
as possible the API is scoped to a new "DEVMEM" module namespace that
only the NVDIMM and CXL subsystems are expected to import.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

show more ...

zstd: Fixing mixed module-builtin objects

With CONFIG_ZSTD_COMPRESS=m and CONFIG_ZSTD_DECOMPRESS=y we end up in
a situation when files from lib/zstd/common/ are compiled once to be
linked later for

zstd: Fixing mixed module-builtin objects

With CONFIG_ZSTD_COMPRESS=m and CONFIG_ZSTD_DECOMPRESS=y we end up in
a situation when files from lib/zstd/common/ are compiled once to be
linked later for ZSTD_DECOMPRESS (build-in) and ZSTD_COMPRESS (module)
even though CFLAGS are different for builtins and modules.
So far somehow this was not a problem but enabling LLVM LTO exposes
the problem as:

ld.lld: error: linking module flags 'Code Model': IDs have conflicting values in 'lib/built-in.a(zstd_common.o at 5868)' and 'ld-temp.o'

This particular conflict is caused by KBUILD_CFLAGS=-mcmodel=medium vs.
KBUILD_CFLAGS_MODULE=-mcmodel=large , modules use the large model on
POWERPC as explained at
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/Makefile?h=v5.18-rc4#n127
but the current use of common files is wrong anyway.

This works around the issue by introducing a zstd_common module with
shared code.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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lib/cpumask: add FORCE_NR_CPUS config option

The size of cpumasks is hard-limited by compile-time parameter NR_CPUS,
but defined at boot-time when kernel parses ACPI/DT tables, and stored in
nr_cpu_

lib/cpumask: add FORCE_NR_CPUS config option

The size of cpumasks is hard-limited by compile-time parameter NR_CPUS,
but defined at boot-time when kernel parses ACPI/DT tables, and stored in
nr_cpu_ids. In many practical cases, number of CPUs for a target is known
at compile time, and can be provided with NR_CPUS.

In that case, compiler may be instructed to rely on NR_CPUS as on actual
number of CPUs, not an upper limit. It allows to optimize many cpumask
routines and significantly shrink size of the kernel image.

This patch adds FORCE_NR_CPUS option to teach the compiler to rely on
NR_CPUS and enable corresponding optimizations.

If FORCE_NR_CPUS=y, kernel will not set nr_cpu_ids at boot, but only check
that the actual number of possible CPUs is equal to NR_CPUS, and WARN if
that doesn't hold.

The new option is especially useful in embedded applications because
kernel configurations are unique for each SoC, the number of CPUs is
constant and known well, and memory limitations are typically harder.

For my 4-CPU ARM64 build with NR_CPUS=4, FORCE_NR_CPUS=y saves 46KB:
add/remove: 3/4 grow/shrink: 46/729 up/down: 652/-46952 (-46300)

Signed-off-by: Yury Norov <yury.norov@gmail.com>

show more ...

crypto: lib - create utils module and move __crypto_memneq into it

As requested at
https://lore.kernel.org/r/YtEgzHuuMts0YBCz@gondor.apana.org.au, move
__crypto_memneq into lib/crypto/ and put it un

crypto: lib - create utils module and move __crypto_memneq into it

As requested at
https://lore.kernel.org/r/YtEgzHuuMts0YBCz@gondor.apana.org.au, move
__crypto_memneq into lib/crypto/ and put it under a new tristate. The
tristate is CRYPTO_LIB_UTILS, and it builds a module libcryptoutils. As
more crypto library utilities are being added, this creates a single
place for them to go without cluttering up the main lib directory.

The module's main file will be lib/crypto/utils.c. However, leave
memneq.c as its own file because of its nonstandard license.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

show more ...

lib/stackdepot: replace CONFIG_STACK_HASH_ORDER with automatic sizing

As Linus explained [1], setting the stackdepot hash table size as a config
option is suboptimal, especially as stackdepot become

lib/stackdepot: replace CONFIG_STACK_HASH_ORDER with automatic sizing

As Linus explained [1], setting the stackdepot hash table size as a config
option is suboptimal, especially as stackdepot becomes a dependency of
less "expert" subsystems than initially (e.g. DRM, networking,
SLUB_DEBUG):

: (a) it introduces a new compile-time question that isn't sane to ask
: a regular user, but is now exposed to regular users.

: (b) this by default uses 1MB of memory for a feature that didn't in
: the past, so now if you have small machines you need to make sure you
: make a special kernel config for them.

Ideally we would employ rhashtable for fully automatic resizing, which
should be feasible for many of the new users, but problematic for the
original users with restricted context that call __stack_depot_save() with
can_alloc == false, i.e. KASAN.

However we can easily remove the config option and scale the hash table
automatically with system memory. The STACK_HASH_MASK constant becomes
stack_hash_mask variable and is used only in one mask operation, so the
overhead should be negligible to none. For early allocation we can employ
the existing alloc_large_system_hash() function and perform similar
scaling for the late allocation.

The existing limits of the config option (between 4k and 1M buckets) are
preserved, and scaling factor is set to one bucket per 16kB memory so on
64bit the max 1M buckets (8MB memory) is achieved with 16GB system, while
a 1GB system will use 512kB.

Because KASAN is reported to need the maximum number of buckets even with
smaller amounts of memory [2], set it as such when kasan_enabled().

If needed, the automatic scaling could be complemented with a boot-time
kernel parameter, but it feels pointless to add it without a specific use
case.

[1] https://lore.kernel.org/all/CAHk-=wjC5nS+fnf6EzRD9yQRJApAhxx7gRB87ZV+pAWo9oVrTg@mail.gmail.com/
[2] https://lore.kernel.org/all/CACT4Y+Y4GZfXOru2z5tFPzFdaSUd+GFc6KVL=bsa0+1m197cQQ@mail.gmail.com/

Link: https://lkml.kernel.org/r/20220620150249.16814-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

lib: Add register read/write tracing support

Generic MMIO read/write i.e., __raw_{read,write}{b,l,w,q} accessors
are typically used to read/write from/to memory mapped registers
and can cause hangs

lib: Add register read/write tracing support

Generic MMIO read/write i.e., __raw_{read,write}{b,l,w,q} accessors
are typically used to read/write from/to memory mapped registers
and can cause hangs or some undefined behaviour in following few
cases,

* If the access to the register space is unclocked, for example: if
there is an access to multimedia(MM) block registers without MM
clocks.

* If the register space is protected and not set to be accessible from
non-secure world, for example: only EL3 (EL: Exception level) access
is allowed and any EL2/EL1 access is forbidden.

* If xPU(memory/register protection units) is controlling access to
certain memory/register space for specific clients.

and more...

Such cases usually results in instant reboot/SErrors/NOC or interconnect
hangs and tracing these register accesses can be very helpful to debug
such issues during initial development stages and also in later stages.

So use ftrace trace events to log such MMIO register accesses which
provides rich feature set such as early enablement of trace events,
filtering capability, dumping ftrace logs on console and many more.

Sample output:

rwmmio_write: __qcom_geni_serial_console_write+0x160/0x1e0 width=32 val=0xa0d5d addr=0xfffffbfffdbff700
rwmmio_post_write: __qcom_geni_serial_console_write+0x160/0x1e0 width=32 val=0xa0d5d addr=0xfffffbfffdbff700
rwmmio_read: qcom_geni_serial_poll_bit+0x94/0x138 width=32 addr=0xfffffbfffdbff610
rwmmio_post_read: qcom_geni_serial_poll_bit+0x94/0x138 width=32 val=0x0 addr=0xfffffbfffdbff610

Co-developed-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com>
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

show more ...

crypto: memneq - move into lib/

This is used by code that doesn't need CONFIG_CRYPTO, so move this into
lib/ with a Kconfig option so that it can be selected by whatever needs
it.

This fixes a link

crypto: memneq - move into lib/

This is used by code that doesn't need CONFIG_CRYPTO, so move this into
lib/ with a Kconfig option so that it can be selected by whatever needs
it.

This fixes a linker error Zheng pointed out when
CRYPTO_MANAGER_DISABLE_TESTS!=y and CRYPTO=m:

lib/crypto/curve25519-selftest.o: In function `curve25519_selftest':
curve25519-selftest.c:(.init.text+0x60): undefined reference to `__crypto_memneq'
curve25519-selftest.c:(.init.text+0xec): undefined reference to `__crypto_memneq'
curve25519-selftest.c:(.init.text+0x114): undefined reference to `__crypto_memneq'
curve25519-selftest.c:(.init.text+0x154): undefined reference to `__crypto_memneq'

Reported-by: Zheng Bin <zhengbin13@huawei.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: stable@vger.kernel.org
Fixes: aa127963f1ca ("crypto: lib/curve25519 - re-add selftests")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

show more ...

lib: add generic polynomial calculation

Some temperature and voltage sensors use a polynomial to convert between
raw data points and actual temperature or voltage. The polynomial is
usually the resu

lib: add generic polynomial calculation

Some temperature and voltage sensors use a polynomial to convert between
raw data points and actual temperature or voltage. The polynomial is
usually the result of a curve fitting of the diode characteristic.

The BT1 PVT hwmon driver already uses such a polynonmial calculation
which is rather generic. Move it to lib/ so other drivers can reuse it.

Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220401214032.3738095-2-michael@walle.cc
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

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crypto: add rocksoft 64b crc guard tag framework

Hardware specific features may be able to calculate a crc64, so provide
a framework for drivers to register their implementation. If nothing is
regis

crypto: add rocksoft 64b crc guard tag framework

Hardware specific features may be able to calculate a crc64, so provide
a framework for drivers to register their implementation. If nothing is
registered, fallback to the generic table lookup implementation. The
implementation is modeled after the crct10dif equivalent.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220303201312.3255347-7-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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ARM: 9178/1: fix unmet dependency on BITREVERSE for HAVE_ARCH_BITREVERSE

Resending this to properly add it to the patch tracker - thanks for letting
me know, Arnd :)

When ARM is enabled, and BITREV

ARM: 9178/1: fix unmet dependency on BITREVERSE for HAVE_ARCH_BITREVERSE

Resending this to properly add it to the patch tracker - thanks for letting
me know, Arnd :)

When ARM is enabled, and BITREVERSE is disabled,
Kbuild gives the following warning:

WARNING: unmet direct dependencies detected for HAVE_ARCH_BITREVERSE
Depends on [n]: BITREVERSE [=n]
Selected by [y]:
- ARM [=y] && (CPU_32v7M [=n] || CPU_32v7 [=y]) && !CPU_32v6 [=n]

This is because ARM selects HAVE_ARCH_BITREVERSE
without selecting BITREVERSE, despite
HAVE_ARCH_BITREVERSE depending on BITREVERSE.

This unmet dependency bug was found by Kismet,
a static analysis tool for Kconfig. Please advise if this
is not the appropriate solution.

Signed-off-by: Julian Braha <julianbraha@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

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lib/stackdepot: allow optional init and stack_table allocation by kvmalloc()

Currently, enabling CONFIG_STACKDEPOT means its stack_table will be
allocated from memblock, even if stack depot ends up

lib/stackdepot: allow optional init and stack_table allocation by kvmalloc()

Currently, enabling CONFIG_STACKDEPOT means its stack_table will be
allocated from memblock, even if stack depot ends up not actually used.
The default size of stack_table is 4MB on 32-bit, 8MB on 64-bit.

This is fine for use-cases such as KASAN which is also a config option
and has overhead on its own. But it's an issue for functionality that
has to be actually enabled on boot (page_owner) or depends on hardware
(GPU drivers) and thus the memory might be wasted. This was raised as
an issue [1] when attempting to add stackdepot support for SLUB's debug
object tracking functionality. It's common to build kernels with
CONFIG_SLUB_DEBUG and enable slub_debug on boot only when needed, or
create only specific kmem caches with debugging for testing purposes.

It would thus be more efficient if stackdepot's table was allocated only
when actually going to be used. This patch thus makes the allocation
(and whole stack_depot_init() call) optional:

- Add a CONFIG_STACKDEPOT_ALWAYS_INIT flag to keep using the current
well-defined point of allocation as part of mem_init(). Make
CONFIG_KASAN select this flag.

- Other users have to call stack_depot_init() as part of their own init
when it's determined that stack depot will actually be used. This may
depend on both config and runtime conditions. Convert current users
which are page_owner and several in the DRM subsystem. Same will be
done for SLUB later.

- Because the init might now be called after the boot-time memblock
allocation has given all memory to the buddy allocator, change
stack_depot_init() to allocate stack_table with kvmalloc() when
memblock is no longer available. Also handle allocation failure by
disabling stackdepot (could have theoretically happened even with
memblock allocation previously), and don't unnecessarily align the
memblock allocation to its own size anymore.

[1] https://lore.kernel.org/all/CAMuHMdW=eoVzM1Re5FVoEN87nKfiLmM2+Ah7eNu2KXEhCvbZyA@mail.gmail.com/

Link: https://lkml.kernel.org/r/20211013073005.11351-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Marco Elver <elver@google.com> # stackdepot
Cc: Marco Elver <elver@google.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Oliver Glitta <glittao@gmail.com>
Cc: Imran Khan <imran.f.khan@oracle.com>
From: Colin Ian King <colin.king@canonical.com>
Subject: lib/stackdepot: fix spelling mistake and grammar in pr_err message

There is a spelling mistake of the work allocation so fix this and
re-phrase the message to make it easier to read.

Link: https://lkml.kernel.org/r/20211015104159.11282-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
From: Vlastimil Babka <vbabka@suse.cz>
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup

On FLATMEM, we call page_ext_init_flatmem_late() just before
kmem_cache_init() which means stack_depot_init() (called by page owner
init) will not recognize properly it should use kvmalloc() and not
memblock_alloc(). memblock_alloc() will also not issue a warning and
return a block memory that can be invalid and cause kernel page fault when
saving stacks, as reported by the kernel test robot [1].

Fix this by moving page_ext_init_flatmem_late() below kmem_cache_init() so
that slab_is_available() is true during stack_depot_init(). SPARSEMEM
doesn't have this issue, as it doesn't do page_ext_init_flatmem_late(),
but a different page_ext_init() even later in the boot process.

Thanks to Mike Rapoport for pointing out the FLATMEM init ordering issue.

While at it, also actually resolve a checkpatch warning in stack_depot_init()
from DRM CI, which was supposed to be in the original patch already.

[1] https://lore.kernel.org/all/20211014085450.GC18719@xsang-OptiPlex-9020/

Link: https://lkml.kernel.org/r/6abd9213-19a9-6d58-cedc-2414386d2d81@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: kernel test robot <oliver.sang@intel.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
From: Vlastimil Babka <vbabka@suse.cz>
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup3

Due to cd06ab2fd48f ("drm/locking: add backtrace for locking contended
locks without backoff") landing recently to -next adding a new stack depot
user in drivers/gpu/drm/drm_modeset_lock.c we need to add an appropriate
call to stack_depot_init() there as well.

Link: https://lkml.kernel.org/r/2a692365-cfa1-64f2-34e0-8aa5674dce5e@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Marco Elver <elver@google.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Oliver Glitta <glittao@gmail.com>
Cc: Imran Khan <imran.f.khan@oracle.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
From: Vlastimil Babka <vbabka@suse.cz>
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup4

Due to 4e66934eaadc ("lib: add reference counting tracking
infrastructure") landing recently to net-next adding a new stack depot
user in lib/ref_tracker.c we need to add an appropriate call to
stack_depot_init() there as well.

Link: https://lkml.kernel.org/r/45c1b738-1a2f-5b5f-2f6d-86fab206d01c@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Cc: Jiri Slab <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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lib/crypto: add prompts back to crypto libraries

Commit 6048fdcc5f269 ("lib/crypto: blake2s: include as built-in") took
away a number of prompt texts from other crypto libraries. This makes
values f

lib/crypto: add prompts back to crypto libraries

Commit 6048fdcc5f269 ("lib/crypto: blake2s: include as built-in") took
away a number of prompt texts from other crypto libraries. This makes
values flip from built-in to module when oldconfig runs, and causes
problems when these crypto libs need to be built in for thingslike
BIG_KEYS.

Fixes: 6048fdcc5f269 ("lib/crypto: blake2s: include as built-in")
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Justin M. Forbes <jforbes@fedoraproject.org>
[Jason: - moved menu into submenu of lib/ instead of root menu
- fixed chacha sub-dependencies for CONFIG_CRYPTO]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

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arch: remove GENERIC_FIND_FIRST_BIT entirely

In 5.12 cycle we enabled GENERIC_FIND_FIRST_BIT config option for ARM64
and MIPS. It increased performance and shrunk .text size; and so far
I didn't rec

arch: remove GENERIC_FIND_FIRST_BIT entirely

In 5.12 cycle we enabled GENERIC_FIND_FIRST_BIT config option for ARM64
and MIPS. It increased performance and shrunk .text size; and so far
I didn't receive any negative feedback on the change.

https://lore.kernel.org/linux-arch/20210225135700.1381396-1-yury.norov@gmail.com/

Now I think it's a good time to switch all architectures to use
find_{first,last}_bit() unconditionally, and so remove corresponding
config option.

The patch does't introduce functioal changes for arc, arm, arm64, mips,
m68k, s390 and x86, for other architectures I expect improvement both in
performance and .text size.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Alexander Lobakin <alobakin@pm.me> (mips)
Reviewed-by: Alexander Lobakin <alobakin@pm.me> (mips)
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Will Deacon <will@kernel.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

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lib: add reference counting tracking infrastructure

It can be hard to track where references are taken and released.

In networking, we have annoying issues at device or netns dismantles,
and we had

lib: add reference counting tracking infrastructure

It can be hard to track where references are taken and released.

In networking, we have annoying issues at device or netns dismantles,
and we had various proposals to ease root causing them.

This patch adds new infrastructure pairing refcount increases
and decreases. This will self document code, because programmers
will have to associate increments/decrements.

This is controled by CONFIG_REF_TRACKER which can be selected
by users of this feature.

This adds both cpu and memory costs, and thus should probably be
used with care.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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lib/test_string.c: move string selftest in the Runtime Testing menu

STRING_SELFTEST is presented in the "Library routines" menu. Move it in
Kernel hacking > Kernel Testing and Coverage > Runtime Te

lib/test_string.c: move string selftest in the Runtime Testing menu

STRING_SELFTEST is presented in the "Library routines" menu. Move it in
Kernel hacking > Kernel Testing and Coverage > Runtime Testing together
with other similar tests found in lib/

--- Runtime Testing
<*> Test functions located in the hexdump module at runtime
<*> Test string functions (NEW)
<*> Test functions located in the string_helpers module at runtime
<*> Test strscpy*() family of functions at runtime
<*> Test kstrto*() family of functions at runtime
<*> Test printf() family of functions at runtime
<*> Test scanf() family of functions at runtime

Link: https://lkml.kernel.org/r/20210719185158.190371-1-mcroce@linux.microsoft.com
Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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