- The TEE shared memory pool based on two pools is replaced with a single
somewhat more capable pool.
- Replaces tee_shm_alloc() and tee_shm_register() with new functions
easier to use and maintain. The TEE subsystem and the TEE drivers are
updated to use the new functions instead.
- The TEE based Trusted keys routines are updated to use the new
simplified functions above.
- The OP-TEE based rng driver is updated to use the new simplified
functions above.
- The TEE_SHM-flags are refactored to better match their usage
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Merge tag 'tee-shm-for-v5.18' of git://git.linaro.org:/people/jens.wiklander/linux-tee into arm/drivers
TEE shared memory cleanup for v5.18
- The TEE shared memory pool based on two pools is replaced with a single
somewhat more capable pool.
- Replaces tee_shm_alloc() and tee_shm_register() with new functions
easier to use and maintain. The TEE subsystem and the TEE drivers are
updated to use the new functions instead.
- The TEE based Trusted keys routines are updated to use the new
simplified functions above.
- The OP-TEE based rng driver is updated to use the new simplified
functions above.
- The TEE_SHM-flags are refactored to better match their usage
* tag 'tee-shm-for-v5.18' of git://git.linaro.org:/people/jens.wiklander/linux-tee:
tee: refactor TEE_SHM_* flags
tee: replace tee_shm_register()
KEYS: trusted: tee: use tee_shm_register_kernel_buf()
tee: add tee_shm_register_{user,kernel}_buf()
optee: add optee_pool_op_free_helper()
tee: replace tee_shm_alloc()
tee: simplify shm pool handling
tee: add tee_shm_alloc_user_buf()
tee: remove unused tee_shm_pool_alloc_res_mem()
hwrng: optee-rng: use tee_shm_alloc_kernel_buf()
optee: use driver internal tee_context for some rpc
Link: https://lore.kernel.org/r/20220218184802.GA968155@jade
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Replace "struct list_head head = LIST_HEAD_INIT(head)" with
"LIST_HEAD(head)" to simplify the code.
Signed-off-by: Cai Huoqing <cai.huoqing@linux.dev>
Link: https://lore.kernel.org/r/20220209032450.37849-1-cai.huoqing@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The only time that we need to wake up /dev/random writers on
RNDCLEARPOOL/RNDZAPPOOL is when we're changing from a value that is
greater than or equal to POOL_MIN_BITS to zero, because if we're
changing from below POOL_MIN_BITS to zero, the writers are already
unblocked.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
When the interrupt handler does not have a valid cycle counter, it calls
get_reg() to read a register from the irq stack, in round-robin.
Currently it does this assuming that registers are 32-bit. This is
_probably_ the case, and probably all platforms without cycle counters
are in fact 32-bit platforms. But maybe not, and either way, it's not
quite correct. This commit fixes that to deal with `unsigned long`
rather than `u32`.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
A situation has come up where there is a slave-only device for the slave
and a separate master device on the same bug. Allow a separate slave
device to be registered.
Signed-off-by: Corey Minyard <minyard@acm.org>
The AST2600 is already described in the bindings, but the driver never
gained a compatible string.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Message-Id: <20220221070351.121905-1-joel@jms.id.au>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
For the irq randomness fast pool, rather than having to use expensive
atomics, which were visibly the most expensive thing in the entire irq
handler, simply take care of the extreme edge case of resetting count to
zero in the cpuhp online handler, just after workqueues have been
reenabled. This simplifies the code a bit and lets us use vanilla
variables rather than atomics, and performance should be improved.
As well, very early on when the CPU comes up, while interrupts are still
disabled, we clear out the per-cpu crng and its batches, so that it
always starts with fresh randomness.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Sultan Alsawaf <sultan@kerneltoast.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
add_hwgenerator_randomness() is a function implemented and documented
inside of random.c. It is the way that hardware RNGs push data into it.
Therefore, it should be declared in random.h. Otherwise sparse complains
with:
random.c:1137:6: warning: symbol 'add_hwgenerator_randomness' was not declared. Should it be static?
The alternative would be to include hw_random.h into random.c, but that
wouldn't really be good for anything except slowing down compile time.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This has no real functional change, as crng_pre_init_inject() (and
before that, crng_slow_init()) always checks for == 0, not >= 2. So
correct the outer unlocked change to reflect that. Before this used
crng_ready(), which was not correct.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
crng_fast_load() and crng_slow_load() have different semantics:
- crng_fast_load() xors and accounts with crng_init_cnt.
- crng_slow_load() hashes and doesn't account.
However add_hwgenerator_randomness() can afford to hash (it's called
from a kthread), and it should account. Additionally, ones that can
afford to hash don't need to take a trylock but can take a normal lock.
So, we combine these into one function, crng_pre_init_inject(), which
allows us to control these in a uniform way. This will make it simpler
later to simplify this all down when the time comes for that.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Since rand_initialize() is run while interrupts are still off and
nothing else is running, we don't need to repeatedly take and release
the pool spinlock, especially in the RDSEED loop.
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
On PREEMPT_RT, it's problematic to take spinlocks from hard irq
handlers. We can fix this by deferring to a workqueue the dumping of
the fast pool into the input pool.
We accomplish this with some careful rules on fast_pool->count:
- When it's incremented to >= 64, we schedule the work.
- If the top bit is set, we never schedule the work, even if >= 64.
- The worker is responsible for setting it back to 0 when it's done.
There are two small issues around using workqueues for this purpose that
we work around.
The first issue is that mix_interrupt_randomness() might be migrated to
another CPU during CPU hotplug. This issue is rectified by checking that
it hasn't been migrated (after disabling irqs). If it has been migrated,
then we set the count to zero, so that when the CPU comes online again,
it can requeue the work. As part of this, we switch to using an
atomic_t, so that the increment in the irq handler doesn't wipe out the
zeroing if the CPU comes back online while this worker is running.
The second issue is that, though relatively minor in effect, we probably
want to make sure we get a consistent view of the pool onto the stack,
in case it's interrupted by an irq while reading. To do this, we don't
reenable irqs until after the copy. There are only 18 instructions
between the cli and sti, so this is a pretty tiny window.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sultan Alsawaf <sultan@kerneltoast.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Now that we've re-documented the various sections, we can remove the
outdated text here and replace it with a high-level overview.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This pulls all of the sysctl-focused functions into the sixth labeled
section.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This pulls all of the userspace read/write-focused functions into the
fifth labeled section.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This pulls all of the entropy collection-focused functions into the
fourth labeled section.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This pulls all of the entropy extraction-focused functions into the
third labeled section.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This pulls all of the crng-focused functions into the second labeled
section.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This pulls all of the readiness waiting-focused functions into the first
labeled section.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This is purely cosmetic. Future work involves figuring out which of
these headers we need and which we don't.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
In preparation for separating responsibilities, break out the entropy
count management part of crng_reseed() into its own function.
No functional changes.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
In the irq handler, we fill out 16 bytes differently on 32-bit and
64-bit platforms, and for 32-bit vs 64-bit cycle counters, which doesn't
always correspond with the bitness of the platform. Whether or not you
like this strangeness, it is a matter of fact. But it might not be a
fact you well realized until now, because the code that loaded the irq
info into 4 32-bit words was quite confusing. Instead, this commit
makes everything explicit by having separate (compile-time) branches for
32-bit and 64-bit types.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Convert the current license into the SPDX notation of "(GPL-2.0 OR
BSD-3-Clause)". This infers GPL-2.0 from the text "ALTERNATIVELY, this
product may be distributed under the terms of the GNU General Public
License, in which case the provisions of the GPL are required INSTEAD OF
the above restrictions" and it infers BSD-3-Clause from the verbatim
BSD 3 clause license in the file.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
These explicit tracepoints aren't really used and show sign of aging.
It's work to keep these up to date, and before I attempted to keep them
up to date, they weren't up to date, which indicates that they're not
really used. These days there are better ways of introspecting anyway.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
With tools like kbench9000 giving more finegrained responses, and this
basically never having been used ever since it was initially added,
let's just get rid of this. There *is* still work to be done on the
interrupt handler, but this really isn't the way it's being developed.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Now that we have an explicit base_crng generation counter, we don't need
a separate one for batched entropy. Rather, we can just move the
generation forward every time we change crng_init state or update the
base_crng key.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
crng_init is protected by primary_crng->lock. Therefore, we need
to hold this lock when increasing crng_init to 2. As we shouldn't
hold this lock for too long, only hold it for those parts which
require protection.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This buffer may contain entropic data that shouldn't stick around longer
than needed, so zero out the temporary buffer at the end of write_pool().
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
In 79a8468747 ("random: check for increase of entropy_count because of
signed conversion"), a number of checks were added around what values
were passed to account(), because account() was doing fancy fixed point
fractional arithmetic, and a user had some ability to pass large values
directly into it. One of things in that commit was limiting those values
to INT_MAX >> 6. The first >> 3 was for bytes to bits, and the next >> 3
was for bits to 1/8 fractional bits.
However, for several years now, urandom reads no longer touch entropy
accounting, and so this check serves no purpose. The current flow is:
urandom_read_nowarn()-->get_random_bytes_user()-->chacha20_block()
Of course, we don't want that size_t to be truncated when adding it into
the ssize_t. But we arrive at urandom_read_nowarn() in the first place
either via ordinary fops, which limits reads to MAX_RW_COUNT, or via
getrandom() which limits reads to INT_MAX.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
We've been using a flurry of int, unsigned int, size_t, and ssize_t.
Let's unify all of this into size_t where it makes sense, as it does in
most places, and leave ssize_t for return values with possible errors.
In addition, keeping with the convention of other functions in this
file, functions that are dealing with raw bytes now take void *
consistently instead of a mix of that and u8 *, because much of the time
we're actually passing some other structure that is then interpreted as
bytes by the function.
We also take the opportunity to fix the outdated and incorrect comment
in get_random_bytes_arch().
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Since we have a hash function that's really fast, and the goal of
crng_slow_load() is reportedly to "touch all of the crng's state", we
can just hash the old state together with the new state and call it a
day. This way we dont need to reason about another LFSR or worry about
various attacks there. This code is only ever used at early boot and
then never again.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Rather than the clunky NUMA full ChaCha state system we had prior, this
commit is closer to the original "fast key erasure RNG" proposal from
<https://blog.cr.yp.to/20170723-random.html>, by simply treating ChaCha
keys on a per-cpu basis.
All entropy is extracted to a base crng key of 32 bytes. This base crng
has a birthdate and a generation counter. When we go to take bytes from
the crng, we first check if the birthdate is too old; if it is, we
reseed per usual. Then we start working on a per-cpu crng.
This per-cpu crng makes sure that it has the same generation counter as
the base crng. If it doesn't, it does fast key erasure with the base
crng key and uses the output as its new per-cpu key, and then updates
its local generation counter. Then, using this per-cpu state, we do
ordinary fast key erasure. Half of this first block is used to overwrite
the per-cpu crng key for the next call -- this is the fast key erasure
RNG idea -- and the other half, along with the ChaCha state, is returned
to the caller. If the caller desires more than this remaining half, it
can generate more ChaCha blocks, unlocked, using the now detached ChaCha
state that was just returned. Crypto-wise, this is more or less what we
were doing before, but this simply makes it more explicit and ensures
that we always have backtrack protection by not playing games with a
shared block counter.
The flow looks like this:
──extract()──► base_crng.key ◄──memcpy()───┐
│ │
└──chacha()──────┬─► new_base_key
└─► crngs[n].key ◄──memcpy()───┐
│ │
└──chacha()───┬─► new_key
└─► random_bytes
│
└────►
There are a few hairy details around early init. Just as was done
before, prior to having gathered enough entropy, crng_fast_load() and
crng_slow_load() dump bytes directly into the base crng, and when we go
to take bytes from the crng, in that case, we're doing fast key erasure
with the base crng rather than the fast unlocked per-cpu crngs. This is
fine as that's only the state of affairs during very early boot; once
the crng initializes we never use these paths again.
In the process of all this, the APIs into the crng become a bit simpler:
we have get_random_bytes(buf, len) and get_random_bytes_user(buf, len),
which both do what you'd expect. All of the details of fast key erasure
and per-cpu selection happen only in a very short critical section of
crng_make_state(), which selects the right per-cpu key, does the fast
key erasure, and returns a local state to the caller's stack. So, we no
longer have a need for a separate backtrack function, as this happens
all at once here. The API then allows us to extend backtrack protection
to batched entropy without really having to do much at all.
The result is a bit simpler than before and has fewer foot guns. The
init time state machine also gets a lot simpler as we don't need to wait
for workqueues to come online and do deferred work. And the multi-core
performance should be increased significantly, by virtue of having hardly
any locking on the fast path.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
During crng_init == 0, we never credit entropy in add_interrupt_
randomness(), but instead dump it directly into the primary_crng. That's
fine, except for the fact that we then wind up throwing away that
entropy later when we switch to extracting from the input pool and
xoring into (and later in this series overwriting) the primary_crng key.
The two other early init sites -- add_hwgenerator_randomness()'s use
crng_fast_load() and add_device_ randomness()'s use of crng_slow_load()
-- always additionally give their inputs to the input pool. But not
add_interrupt_randomness().
This commit fixes that shortcoming by calling mix_pool_bytes() after
crng_fast_load() in add_interrupt_randomness(). That's partially
verboten on PREEMPT_RT, where it implies taking spinlock_t from an IRQ
handler. But this also only happens during early boot and then never
again after that. Plus it's a trylock so it has the same considerations
as calling crng_fast_load(), which we're already using.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Suggested-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Continuing the reasoning of "random: ensure early RDSEED goes through
mixer on init", we don't want RDRAND interacting with anything without
going through the mixer function, as a backdoored CPU could presumably
cancel out data during an xor, which it'd have a harder time doing when
being forced through a cryptographic hash function. There's actually no
need at all to be calling RDRAND in write_pool(), because before we
extract from the pool, we always do so with 32 bytes of RDSEED hashed in
at that stage. Xoring at this stage is needless and introduces a minor
liability.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Continuing the reasoning of "random: use RDSEED instead of RDRAND in
entropy extraction" from this series, at init time we also don't want to
be xoring RDSEED directly into the crng. Instead it's safer to put it
into our entropy collector and then re-extract it, so that it goes
through a hash function with preimage resistance. As a matter of hygiene,
we also order these now so that the RDSEED byte are hashed in first,
followed by the bytes that are likely more predictable (e.g. utsname()).
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This is a preparatory commit for the following one. We simply inline the
various functions that rand_initialize() calls that have no other
callers. The compiler was doing this anyway before. Doing this will
allow us to reorganize this after. We can then move the trust_cpu and
parse_trust_cpu definitions a bit closer to where they're actually used,
which makes the code easier to read.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
As the comment said, this is indeed a "hack". Since it was introduced,
it's been a constant state machine nightmare, with lots of subtle early
boot issues and a wildly complex set of machinery to keep everything in
sync. Rather than continuing to play whack-a-mole with this approach,
this commit simply removes it entirely. This commit is preparation for
"random: use simpler fast key erasure flow on per-cpu keys" in this
series, which introduces a simpler (and faster) mechanism to accomplish
the same thing.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
When /dev/random was directly connected with entropy extraction, without
any expansion stage, extract_buf() was called for every 10 bytes of data
read from /dev/random. For that reason, RDRAND was used rather than
RDSEED. At the same time, crng_reseed() was still only called every 5
minutes, so there RDSEED made sense.
Those olden days were also a time when the entropy collector did not use
a cryptographic hash function, which meant most bets were off in terms
of real preimage resistance. For that reason too it didn't matter
_that_ much whether RDSEED was mixed in before or after entropy
extraction; both choices were sort of bad.
But now we have a cryptographic hash function at work, and with that we
get real preimage resistance. We also now only call extract_entropy()
every 5 minutes, rather than every 10 bytes. This allows us to do two
important things.
First, we can switch to using RDSEED in extract_entropy(), as Dominik
suggested. Second, we can ensure that RDSEED input always goes into the
cryptographic hash function with other things before being used
directly. This eliminates a category of attacks in which the CPU knows
the current state of the crng and knows that we're going to xor RDSEED
into it, and so it computes a malicious RDSEED. By going through our
hash function, it would require the CPU to compute a preimage on the
fly, which isn't going to happen.
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Suggested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
crng_init is protected by primary_crng->lock, so keep holding that lock
when incrementing crng_init from 0 to 1 in crng_fast_load(). The call to
pr_notice() can wait until the lock is released; this code path cannot
be reached twice, as crng_fast_load() aborts early if crng_init > 0.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Rather than use spinlocks to protect batched entropy, we can instead
disable interrupts locally, since we're dealing with per-cpu data, and
manage resets with a basic generation counter. At the same time, we
can't quite do this on PREEMPT_RT, where we still want spinlocks-as-
mutexes semantics. So we use a local_lock_t, which provides the right
behavior for each. Because this is a per-cpu lock, that generation
counter is still doing the necessary CPU-to-CPU communication.
This should improve performance a bit. It will also fix the linked splat
that Jonathan received with a PROVE_RAW_LOCK_NESTING=y.
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Suggested-by: Andy Lutomirski <luto@kernel.org>
Reported-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Tested-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/lkml/YfMa0QgsjCVdRAvJ@latitude/
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The primary_crng is always reseeded from the input_pool, while the NUMA
crngs are always reseeded from the primary_crng. Remove the redundant
'use_input_pool' parameter from crng_reseed() and just directly check
whether the crng is the primary_crng.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This is called from various hwgenerator drivers, so rather than having
one "safe" version for userspace and one "unsafe" version for the
kernel, just make everything safe; the checks are cheap and sensible to
have anyway.
Reported-by: Sultan Alsawaf <sultan@kerneltoast.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Now that POOL_BITS == POOL_MIN_BITS, we must unconditionally wake up
entropy writers after every extraction. Therefore there's no point of
write_wakeup_threshold, so we can move it to the dustbin of unused
compatibility sysctls. While we're at it, we can fix a small comparison
where we were waking up after <= min rather than < min.
Cc: Theodore Ts'o <tytso@mit.edu>
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
30e37ec516 ("random: account for entropy loss due to overwrites")
assumed that adding new entropy to the LFSR pool probabilistically
cancelled out old entropy there, so entropy was credited asymptotically,
approximating Shannon entropy of independent sources (rather than a
stronger min-entropy notion) using 1/8th fractional bits and replacing
a constant 2-2/√𝑒 term (~0.786938) with 3/4 (0.75) to slightly
underestimate it. This wasn't superb, but it was perhaps better than
nothing, so that's what was done. Which entropy specifically was being
cancelled out and how much precisely each time is hard to tell, though
as I showed with the attack code in my previous commit, a motivated
adversary with sufficient information can actually cancel out
everything.
Since we're no longer using an LFSR for entropy accumulation, this
probabilistic cancellation is no longer relevant. Rather, we're now
using a computational hash function as the accumulator and we've
switched to working in the random oracle model, from which we can now
revisit the question of min-entropy accumulation, which is done in
detail in <https://eprint.iacr.org/2019/198>.
Consider a long input bit string that is built by concatenating various
smaller independent input bit strings. Each one of these inputs has a
designated min-entropy, which is what we're passing to
credit_entropy_bits(h). When we pass the concatenation of these to a
random oracle, it means that an adversary trying to receive back the
same reply as us would need to become certain about each part of the
concatenated bit string we passed in, which means becoming certain about
all of those h values. That means we can estimate the accumulation by
simply adding up the h values in calls to credit_entropy_bits(h);
there's no probabilistic cancellation at play like there was said to be
for the LFSR. Incidentally, this is also what other entropy accumulators
based on computational hash functions do as well.
So this commit replaces credit_entropy_bits(h) with essentially `total =
min(POOL_BITS, total + h)`, done with a cmpxchg loop as before.
What if we're wrong and the above is nonsense? It's not, but let's
assume we don't want the actual _behavior_ of the code to change much.
Currently that behavior is not extracting from the input pool until it
has 128 bits of entropy in it. With the old algorithm, we'd hit that
magic 128 number after roughly 256 calls to credit_entropy_bits(1). So,
we can retain more or less the old behavior by waiting to extract from
the input pool until it hits 256 bits of entropy using the new code. For
people concerned about this change, it means that there's not that much
practical behavioral change. And for folks actually trying to model
the behavior rigorously, it means that we have an even higher margin
against attacks.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Our pool is 256 bits, and we only ever use all of it or don't use it at
all, which is decided by whether or not it has at least 128 bits in it.
So we can drastically simplify the accounting and cmpxchg loop to do
exactly this. While we're at it, we move the minimum bit size into a
constant so it can be shared between the two places where it matters.
The reason we want any of this is for the case in which an attacker has
compromised the current state, and then bruteforces small amounts of
entropy added to it. By demanding a particular minimum amount of entropy
be present before reseeding, we make that bruteforcing difficult.
Note that this rationale no longer includes anything about /dev/random
blocking at the right moment, since /dev/random no longer blocks (except
for at ~boot), but rather uses the crng. In a former life, /dev/random
was different and therefore required a more nuanced account(), but this
is no longer.
Behaviorally, nothing changes here. This is just a simplification of
the code.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The current 4096-bit LFSR used for entropy collection had a few
desirable attributes for the context in which it was created. For
example, the state was huge, which meant that /dev/random would be able
to output quite a bit of accumulated entropy before blocking. It was
also, in its time, quite fast at accumulating entropy byte-by-byte,
which matters given the varying contexts in which mix_pool_bytes() is
called. And its diffusion was relatively high, which meant that changes
would ripple across several words of state rather quickly.
However, it also suffers from a few security vulnerabilities. In
particular, inputs learned by an attacker can be undone, but moreover,
if the state of the pool leaks, its contents can be controlled and
entirely zeroed out. I've demonstrated this attack with this SMT2
script, <https://xn--4db.cc/5o9xO8pb>, which Boolector/CaDiCal solves in
a matter of seconds on a single core of my laptop, resulting in little
proof of concept C demonstrators such as <https://xn--4db.cc/jCkvvIaH/c>.
For basically all recent formal models of RNGs, these attacks represent
a significant cryptographic flaw. But how does this manifest
practically? If an attacker has access to the system to such a degree
that he can learn the internal state of the RNG, arguably there are
other lower hanging vulnerabilities -- side-channel, infoleak, or
otherwise -- that might have higher priority. On the other hand, seed
files are frequently used on systems that have a hard time generating
much entropy on their own, and these seed files, being files, often leak
or are duplicated and distributed accidentally, or are even seeded over
the Internet intentionally, where their contents might be recorded or
tampered with. Seen this way, an otherwise quasi-implausible
vulnerability is a bit more practical than initially thought.
Another aspect of the current mix_pool_bytes() function is that, while
its performance was arguably competitive for the time in which it was
created, it's no longer considered so. This patch improves performance
significantly: on a high-end CPU, an i7-11850H, it improves performance
of mix_pool_bytes() by 225%, and on a low-end CPU, a Cortex-A7, it
improves performance by 103%.
This commit replaces the LFSR of mix_pool_bytes() with a straight-
forward cryptographic hash function, BLAKE2s, which is already in use
for pool extraction. Universal hashing with a secret seed was considered
too, something along the lines of <https://eprint.iacr.org/2013/338>,
but the requirement for a secret seed makes for a chicken & egg problem.
Instead we go with a formally proven scheme using a computational hash
function, described in sections 5.1, 6.4, and B.1.8 of
<https://eprint.iacr.org/2019/198>.
BLAKE2s outputs 256 bits, which should give us an appropriate amount of
min-entropy accumulation, and a wide enough margin of collision
resistance against active attacks. mix_pool_bytes() becomes a simple
call to blake2s_update(), for accumulation, while the extraction step
becomes a blake2s_final() to generate a seed, with which we can then do
a HKDF-like or BLAKE2X-like expansion, the first part of which we fold
back as an init key for subsequent blake2s_update()s, and the rest we
produce to the caller. This then is provided to our CRNG like usual. In
that expansion step, we make opportunistic use of 32 bytes of RDRAND
output, just as before. We also always reseed the crng with 32 bytes,
unconditionally, or not at all, rather than sometimes with 16 as before,
as we don't win anything by limiting beyond the 16 byte threshold.
Going for a hash function as an entropy collector is a conservative,
proven approach. The result of all this is a much simpler and much less
bespoke construction than what's there now, which not only plugs a
vulnerability but also improves performance considerably.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The rng_quality sysfs attribute returns the quality setting for the
currently active hw_random device, in entropy bits per 1024 bits of
input. Storing a value between 0 and 1024 to this file updates this
estimate accordingly.
Based on the updates to the quality setting, the rngd kernel thread
may be stopped (if no hw_random device is trusted to return entropy),
may be started (if the quality setting is increased from zero), or
may use a different hw_random source (if that has higher quality
output).
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The current_quality variable exposed as a module parameter is
fundamentally broken: If it is set at boot time, it is overwritten once
the first hw rng device is loaded; if it is set at runtime, it is
without effect if the hw rng device had its quality value set to 0 (and
no default_quality was set); and if a new rng is selected, it gets
overwritten. Therefore, mark it as obsolete, and replace it by the
per-rng quality setting.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Extract the start/stop logic for the in-kernel rngd thread to
a separate function.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There is no real reason why this list needs to be kept ordered by
the driver-provided quality value -- a value which is set only by
a handful of hw_random devices anyway.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Uses the new simplified tee_shm_alloc_kernel_buf() function instead of
the old deprecated tee_shm_alloc() function which required specific
TEE_SHM-flags.
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
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Merge 5.17-rc4 into char-misc-next
We need the char/misc fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Backmerge tag 'v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next
Daniel asked for this for some intel deps, so let's do it now.
Signed-off-by: Dave Airlie <airlied@redhat.com>
The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)
So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
In case the entropy quality is low, there may be less than one bit to
credit in the call to add_hwgenerator_randomness(): The number of bytes
returned by rng_get_data() multiplied by the current quality (in entropy
bits per 1024 bits of input) must be larger than 128 to credit at least
one bit. However, imx-rngc.c sets the quality to 19, but may return less
than 32 bytes; hid_u2fzero.c sets the quality to 1; and users may override
the quality setting manually.
In case there is less than one bit to credit, keep track of it and add
that credit to the next iteration.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
For two reasons, current_quality may become zero within the rngd
kernel thread: (1) The user lowers current_quality to 0 by writing
to the sysfs module parameter file (note that increasing the quality
from zero is without effect at the moment), or (2) there are two or
more hwrng devices registered, and those which provide quality>0 are
unregistered, but one with quality==0 remains.
If current_quality is 0, the randomness is not trusted and cannot help
to increase the entropy count. That will lead to continuous calls to
the hwrngd thread and continuous stirring of the input pool with
untrusted bits.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In case the user-specified rng device is not working, it is not used;
therefore cur_rng_set_by_user must not be set to 1.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Using rng_buffer in add_early_randomness() may race with rng_dev_read().
Use rng_fillbuf instead, as it is otherwise only used within the kernel
by hwrng_fillfn() and therefore never exposed to userspace.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
According to <linux/hw_random.h>, the @max parameter of the ->read
callback "is a multiple of 4 and >= 32 bytes". That promise was not
kept by add_early_randomness(), which only asked for 16 bytes. As
rng_buffer_size() is at least 32, we can simply ask for 32 bytes.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
hw-random device drivers depend on the hw-random core being
initialized. Make this ordering explicit, also for the case
these drivers are built-in. As the core itself depends on
misc_register() which is set up at subsys_initcall time,
advance the initialization of the core (only) to the
fs_initcall() level.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crng_finalize_init() returns instantly if it is called for another pool
than primary_crng. The test whether crng_finalize_init() is still required
can be moved to the relevant caller in crng_reseed(), and
crng_need_final_init can be reset to false if crng_finalize_init() is
called with workqueues ready. Then, no previous callsite will call
crng_finalize_init() unless it is needed, and we can get rid of the
superfluous function parameter.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Both crng_initialize_primary() and crng_init_try_arch_early() are
only called for the primary_pool. Accessing it directly instead of
through a function parameter simplifies the code.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
When account() is called, and the amount of entropy dips below
random_write_wakeup_bits, we wake up the random writers, so that they
can write some more in. However, the RNDZAPENTCNT/RNDCLEARPOOL ioctl
sets the entropy count to zero -- a potential reduction just like
account() -- but does not unblock writers. This commit adds the missing
logic to that ioctl to unblock waiting writers.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The rngd kernel thread may sleep indefinitely if the entropy count is
kept above random_write_wakeup_bits by other entropy sources. To make
best use of multiple sources of randomness, mix entropy from hardware
RNGs into the pool at least once within CRNG_RESEED_INTERVAL.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
On all arch using hpet, only i386 miss writeq/readq.
Instead of rewriting them, use linux/io-64-nonatomic-lo-hi.h which
already have them.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Link: https://lore.kernel.org/r/20220125140352.4085290-1-clabbe@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no good reason to keep genhd.h separate from the main blkdev.h
header that includes it. So fold the contents of genhd.h into blkdev.h
and remove genhd.h entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
UAPI Changes:
- Fix invalid IN_FORMATS blob when plane->format_mod_supported is NULL.
Cross-subsystem Changes:
- Assorted dt bindings updates.
- Fix vga16fb vga checking on x86.
- Fix extra semicolon in rwsem.h's _down_write_nest_lock.
- Assorted small fixes to agp and fbdev drivers.
- Fix oops in creating a udmabuf with 0 pages.
- Hot-unplug firmware fb devices on forced removal
- Reqquest memory region in simplefb and simpledrm, and don't make the ioresource as busy.
Core Changes:
- Mock a drm_plane in drm-plane-helper selftest.
- Assorted bug fixes to device logging, dbi.
- Use DP helper for sink count in mst.
- Assorted documentation fixes.
- Assorted small fixes.
- Move DP headers to drm/dp, and add a drm dp helper module.
- Move the buddy allocator from i915 to common drm.
- Add simple pci and platform module init macros to remove a lot of boilerplate from some drivers.
- Support microsoft extension for HMDs and specialized monitors.
- Improve edid parser's deep color handling.
- Add type 7 timing support to edid parser.
- Add a weak backpointer to the ttm_bo from ttm_resource
- Add 3 eDP panels.
Driver Changes:
- Add support for HDMI and JZ4780 to ingenic.
- Add support for higher DP/eDP bitrates to nouveau.
- Assorted driver fixes to tilcdc, vmwgfx, sn65dsi83, meson, stm, panfrost, v3d, gma500, vc4, virtio, mgag200, ast, radeon, amdgpu, nouveau, various bridge drivers.
- Convert and revert exynos dsi support to bridge driver.
- Add vcc supply regulator support for sn65dsi83.
- More conversion of bridge/chipone-icn6211 to atomic.
- Remove conflicting fb's from stm, and add support for new hw version.
- Add device link in parade-ps8640 to fix suspend/resume.
- Update Boe-tv110c9m init sequence.
- Add wide screen support to AST2600.
- Fix omapdrm implicit dma_buf fencing.
- Add support for multiple overlay planes to vkms.
- Convert bridge/anx7625 to atomic, add HDCP support,
add eld support for audio, and fix HPD.
- Add driver for ChromeOS privacy screen.
- Handover display from firmware to vc4 more gracefully, and support nomodeset.
- Add flexible and ycbcr pixel formats to stm/ltdc.
- Convert exynos mipi dsi to atomic.
- Add initial dual core group GPUs support to panfrost.
- No longer add exclusive fence in amdgpu as shared fence.
- Add CSC and full range supoprt to vc4.
- Shutdown the display on system shutdown and unbind.
- Add Multi-Inno Technology MI0700S4T-6 simple panel.
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Merge tag 'drm-misc-next-2022-01-27' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
[airlied: add two missing Kconfig]
drm-misc-next for v5.18:
UAPI Changes:
- Fix invalid IN_FORMATS blob when plane->format_mod_supported is NULL.
Cross-subsystem Changes:
- Assorted dt bindings updates.
- Fix vga16fb vga checking on x86.
- Fix extra semicolon in rwsem.h's _down_write_nest_lock.
- Assorted small fixes to agp and fbdev drivers.
- Fix oops in creating a udmabuf with 0 pages.
- Hot-unplug firmware fb devices on forced removal
- Reqquest memory region in simplefb and simpledrm, and don't make the ioresource as busy.
Core Changes:
- Mock a drm_plane in drm-plane-helper selftest.
- Assorted bug fixes to device logging, dbi.
- Use DP helper for sink count in mst.
- Assorted documentation fixes.
- Assorted small fixes.
- Move DP headers to drm/dp, and add a drm dp helper module.
- Move the buddy allocator from i915 to common drm.
- Add simple pci and platform module init macros to remove a lot of boilerplate from some drivers.
- Support microsoft extension for HMDs and specialized monitors.
- Improve edid parser's deep color handling.
- Add type 7 timing support to edid parser.
- Add a weak backpointer to the ttm_bo from ttm_resource
- Add 3 eDP panels.
Driver Changes:
- Add support for HDMI and JZ4780 to ingenic.
- Add support for higher DP/eDP bitrates to nouveau.
- Assorted driver fixes to tilcdc, vmwgfx, sn65dsi83, meson, stm, panfrost, v3d, gma500, vc4, virtio, mgag200, ast, radeon, amdgpu, nouveau, various bridge drivers.
- Convert and revert exynos dsi support to bridge driver.
- Add vcc supply regulator support for sn65dsi83.
- More conversion of bridge/chipone-icn6211 to atomic.
- Remove conflicting fb's from stm, and add support for new hw version.
- Add device link in parade-ps8640 to fix suspend/resume.
- Update Boe-tv110c9m init sequence.
- Add wide screen support to AST2600.
- Fix omapdrm implicit dma_buf fencing.
- Add support for multiple overlay planes to vkms.
- Convert bridge/anx7625 to atomic, add HDCP support,
add eld support for audio, and fix HPD.
- Add driver for ChromeOS privacy screen.
- Handover display from firmware to vc4 more gracefully, and support nomodeset.
- Add flexible and ycbcr pixel formats to stm/ltdc.
- Convert exynos mipi dsi to atomic.
- Add initial dual core group GPUs support to panfrost.
- No longer add exclusive fence in amdgpu as shared fence.
- Add CSC and full range supoprt to vc4.
- Shutdown the display on system shutdown and unbind.
- Add Multi-Inno Technology MI0700S4T-6 simple panel.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/456a23c6-7324-7543-0c45-751f30ef83f7@linux.intel.com
The Cavium ThunderX Random Number Generator is only present on Cavium
ThunderX SoCs, and not available as an independent PCIe endpoint. Hence
add a dependency on ARCH_THUNDER, to prevent asking the user about this
driver when configuring a kernel without Cavium Thunder SoC support.
Fixes: cc2f1908c6 ("hwrng: cavium - Add Cavium HWRNG driver for ThunderX SoC.")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
dishes, this makes it very difficult to maintain.
To help with this maintenance let's start by moving sysctls to places
where they actually belong. The proc sysctl maintainers do not want to
know what sysctl knobs you wish to add for your own piece of code, we
just care about the core logic.
So move the random sysctls to their own file and use
register_sysctl_init().
[mcgrof@kernel.org: commit log update to justify the move]
Link: https://lkml.kernel.org/r/20211124231435.1445213-3-mcgrof@kernel.org
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Qing Wang <wangqing@vivo.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "sysctl: second set of kernel/sysctl cleanups", v2.
This is the 2nd set of kernel/sysctl.c cleanups. The diff stat should
reflect how this is a much better way to deal with theses. Fortunately
coccinelle can be used to ensure correctness for most of these and/or
future merge conflicts.
Note that since this is part of a larger effort to cleanup
kernel/sysctl.c I think we have no other option but to go with merging
these patches in either Andrew's tree or keep them staged in a separate
tree and send a merge request later. Otherwise kernel/sysctl.c will end
up becoming a sore spot for the next merge window.
This patch (of 8):
There is no need to user boiler plate code to specify a set of base
directories we're going to stuff sysctls under. Simplify this by using
register_sysctl() and specifying the directory path directly.
// pycocci sysctl-subdir-register-sysctl-simplify.cocci drivers/char/hpet.c
@c1@
expression E1;
identifier subdir, sysctls;
@@
static struct ctl_table subdir[] = {
{
.procname = E1,
.maxlen = 0,
.mode = 0555,
.child = sysctls,
},
{ }
};
@c2@
identifier c1.subdir;
expression E2;
identifier base;
@@
static struct ctl_table base[] = {
{
.procname = E2,
.maxlen = 0,
.mode = 0555,
.child = subdir,
},
{ }
};
@c3@
identifier c2.base;
identifier header;
@@
header = register_sysctl_table(base);
@r1 depends on c1 && c2 && c3@
expression c1.E1;
identifier c1.subdir, c1.sysctls;
@@
-static struct ctl_table subdir[] = {
- {
- .procname = E1,
- .maxlen = 0,
- .mode = 0555,
- .child = sysctls,
- },
- { }
-};
@r2 depends on c1 && c2 && c3@
identifier c1.subdir;
expression c2.E2;
identifier c2.base;
@@
-static struct ctl_table base[] = {
- {
- .procname = E2,
- .maxlen = 0,
- .mode = 0555,
- .child = subdir,
- },
- { }
-};
@initialize:python@
@@
def make_my_fresh_expression(s1, s2):
return '"' + s1.strip('"') + "/" + s2.strip('"') + '"'
@r3 depends on c1 && c2 && c3@
expression c1.E1;
identifier c1.sysctls;
expression c2.E2;
identifier c2.base;
identifier c3.header;
fresh identifier E3 = script:python(E2, E1) { make_my_fresh_expression(E2, E1) };
@@
header =
-register_sysctl_table(base);
+register_sysctl(E3, sysctls);
Generated-by: Coccinelle SmPL
Link: https://lkml.kernel.org/r/20211123202422.819032-1-mcgrof@kernel.org
Link: https://lkml.kernel.org/r/20211123202422.819032-2-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Qing Wang <wangqing@vivo.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that have_bytes is never modified, we can simplify this function.
First, we move the check for negative entropy_count to be first. That
ensures that subsequent reads of this will be non-negative. Then,
have_bytes and ibytes can be folded into their one use site in the
min_t() function.
Suggested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This is an old driver that has seen a lot of different eras of kernel
coding style. In an effort to make it easier to code for, unify the
coding style around the current norm, by accepting some of -- but
certainly not all of -- the suggestions from clang-format. This should
remove ambiguity in coding style, especially with regards to spacing,
when code is being changed or amended. Consequently it also makes code
review easier on the eyes, following one uniform style rather than
several.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This gets rid of another abstraction we no longer need. It would be nice
if we could instead make pool an array rather than a pointer, but the
latent entropy plugin won't be able to do its magic in that case. So
instead we put all accesses to the input pool's actual data through the
input_pool_data array directly.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The entropy estimator is calculated in terms of 1/8 bits, which means
there are various constants where things are shifted by 3. Move these
into our pool info enum with the other relevant constants. While we're
at it, move an English assertion about sizes into a proper BUILD_BUG_ON
so that the compiler can ensure this invariant.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The other pool constants are prepended with POOL_, but not these last
ones. Rename them. This will then let us move them into the enum in the
following commit.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
We already had the POOL_* constants, so deduplicate the older INPUT_POOL
ones. As well, fold EXTRACT_SIZE into the poolinfo enum, since it's
related.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
We no longer have an output pool. Rather, we have just a wakeup bits
threshold for /dev/random reads, presumably so that processes don't
hang. This value, random_write_wakeup_bits, is configurable anyway. So
all the no longer usefully named OUTPUT_POOL constants were doing was
setting a reasonable default for random_write_wakeup_bits. This commit
gets rid of the constants and just puts it all in the default value of
random_write_wakeup_bits.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Originally, the RNG used several pools, so having things abstracted out
over a generic entropy_store object made sense. These days, there's only
one input pool, and then an uneven mix of usage via the abstraction and
usage via &input_pool. Rather than this uneasy mixture, just get rid of
the abstraction entirely and have things always use the global. This
simplifies the code and makes reading it a bit easier.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This argument is always set to zero, as a result of us not caring about
keeping a certain amount reserved in the pool these days. So just remove
it and cleanup the function signatures.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
There were a few things added under the "if (fips_enabled)" banner,
which never really got completed, and the FIPS people anyway are
choosing a different direction. Rather than keep around this halfbaked
code, get rid of it so that we can focus on a single design of the RNG
rather than two designs.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Rather than using the userspace type, __uXX, switch to using uXX. And
rather than using variously chosen `char *` or `unsigned char *`, use
`u8 *` uniformly for things that aren't strings, in the case where we
are doing byte-by-byte traversal.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Now that we're only using one polynomial, we can cleanup its
representation into constants, instead of passing around pointers
dynamically to select different polynomials. This improves the codegen
and makes the code a bit more straightforward.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
partial support for < MAX_ORDER - 1 granularity for virtio-mem
driver_override for vdpa
sysfs ABI documentation for vdpa
multiqueue config support for mlx5 vdpa
Misc fixes, cleanups.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio updates from Michael Tsirkin:
"virtio,vdpa,qemu_fw_cfg: features, cleanups, and fixes.
- partial support for < MAX_ORDER - 1 granularity for virtio-mem
- driver_override for vdpa
- sysfs ABI documentation for vdpa
- multiqueue config support for mlx5 vdpa
- and misc fixes, cleanups"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (42 commits)
vdpa/mlx5: Fix tracking of current number of VQs
vdpa/mlx5: Fix is_index_valid() to refer to features
vdpa: Protect vdpa reset with cf_mutex
vdpa: Avoid taking cf_mutex lock on get status
vdpa/vdpa_sim_net: Report max device capabilities
vdpa: Use BIT_ULL for bit operations
vdpa/vdpa_sim: Configure max supported virtqueues
vdpa/mlx5: Report max device capabilities
vdpa: Support reporting max device capabilities
vdpa/mlx5: Restore cur_num_vqs in case of failure in change_num_qps()
vdpa: Add support for returning device configuration information
vdpa/mlx5: Support configuring max data virtqueue
vdpa/mlx5: Fix config_attr_mask assignment
vdpa: Allow to configure max data virtqueues
vdpa: Read device configuration only if FEATURES_OK
vdpa: Sync calls set/get config/status with cf_mutex
vdpa/mlx5: Distribute RX virtqueues in RQT object
vdpa: Provide interface to read driver features
vdpa: clean up get_config_size ret value handling
virtio_ring: mark ring unused on error
...
The strlcpy should not be used because it doesn't limit the source
length. So that it will lead some potential bugs.
But the strscpy doesn't require reading memory from the src string
beyond the specified "count" bytes, and since the return value is
easier to error-check than strlcpy()'s. In addition, the implementation
is robust to the string changing out from underneath it, unlike the
current strlcpy() implementation.
Thus, replace strlcpy with strscpy.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Message-Id: <20211222032707.1912186-1-wangborong@cdjrlc.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
ident is not modified and can be made const to allow the compiler to put
it in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Message-Id: <20211128220154.32927-1-rikard.falkeborn@gmail.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
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Merge tag 'pci-v5.17-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Use pci_find_vsec_capability() instead of open-coding it (Andy
Shevchenko)
- Convert pci_dev_present() stub from macro to static inline to avoid
'unused variable' errors (Hans de Goede)
- Convert sysfs slot attributes from default_attrs to default_groups
(Greg Kroah-Hartman)
- Use DWORD accesses for LTR, L1 SS to avoid BayHub OZ711LV2 erratum
(Rajat Jain)
- Remove unnecessary initialization of static variables (Longji Guo)
Resource management:
- Always write Intel I210 ROM BAR on update to work around device
defect (Bjorn Helgaas)
PCIe native device hotplug:
- Fix pciehp lockdep errors on Thunderbolt undock (Hans de Goede)
- Fix infinite loop in pciehp IRQ handler on power fault (Lukas
Wunner)
Power management:
- Convert amd64-agp, sis-agp, via-agp from legacy PCI power
management to generic power management (Vaibhav Gupta)
IOMMU:
- Add function 1 DMA alias quirk for Marvell 88SE9125 SATA controller
so it can work with an IOMMU (Yifeng Li)
Error handling:
- Add PCI_ERROR_RESPONSE and related definitions for signaling and
checking for transaction errors on PCI (Naveen Naidu)
- Fabricate PCI_ERROR_RESPONSE data (~0) in config read wrappers,
instead of in host controller drivers, when transactions fail on
PCI (Naveen Naidu)
- Use PCI_POSSIBLE_ERROR() to check for possible failure of config
reads (Naveen Naidu)
Peer-to-peer DMA:
- Add Logan Gunthorpe as P2PDMA maintainer (Bjorn Helgaas)
ASPM:
- Calculate link L0s and L1 exit latencies when needed instead of
caching them (Saheed O. Bolarinwa)
- Calculate device L0s and L1 acceptable exit latencies when needed
instead of caching them (Saheed O. Bolarinwa)
- Remove struct aspm_latency since it's no longer needed (Saheed O.
Bolarinwa)
APM X-Gene PCIe controller driver:
- Fix IB window setup, which was broken by the fact that IB resources
are now sorted in address order instead of DT dma-ranges order (Rob
Herring)
Apple PCIe controller driver:
- Enable clock gating to save power (Hector Martin)
- Fix REFCLK1 enable/poll logic (Hector Martin)
Broadcom STB PCIe controller driver:
- Declare bitmap correctly for use by bitmap interfaces (Christophe
JAILLET)
- Clean up computation of legacy and non-legacy MSI bitmasks (Florian
Fainelli)
- Update suspend/resume/remove error handling to warn about errors
and not fail the operation (Jim Quinlan)
- Correct the "pcie" and "msi" interrupt descriptions in DT binding
(Jim Quinlan)
- Add DT bindings for endpoint voltage regulators (Jim Quinlan)
- Split brcm_pcie_setup() into two functions (Jim Quinlan)
- Add mechanism for turning on voltage regulators for connected
devices (Jim Quinlan)
- Turn voltage regulators for connected devices on/off when bus is
added or removed (Jim Quinlan)
- When suspending, don't turn off voltage regulators for wakeup
devices (Jim Quinlan)
Freescale i.MX6 PCIe controller driver:
- Add i.MX8MM support (Richard Zhu)
Freescale Layerscape PCIe controller driver:
- Use DWC common ops instead of layerscape-specific link-up functions
(Hou Zhiqiang)
Intel VMD host bridge driver:
- Honor platform ACPI _OSC feature negotiation for Root Ports below
VMD (Kai-Heng Feng)
- Add support for Raptor Lake SKUs (Karthik L Gopalakrishnan)
- Reset everything below VMD before enumerating to work around
failure to enumerate NVMe devices when guest OS reboots (Nirmal
Patel)
Bridge emulation (used by Marvell Aardvark and MVEBU):
- Make emulated ROM BAR read-only by default (Pali Rohár)
- Make some emulated legacy PCI bits read-only for PCIe devices (Pali
Rohár)
- Update reserved bits in emulated PCIe Capability (Pali Rohár)
- Allow drivers to emulate different PCIe Capability versions (Pali
Rohár)
- Set emulated Capabilities List bit for all PCIe devices, since they
must have at least a PCIe Capability (Pali Rohár)
Marvell Aardvark PCIe controller driver:
- Add bridge emulation definitions for PCIe DEVCAP2, DEVCTL2,
DEVSTA2, LNKCAP2, LNKCTL2, LNKSTA2, SLTCAP2, SLTCTL2, SLTSTA2 (Pali
Rohár)
- Add aardvark support for DEVCAP2, DEVCTL2, LNKCAP2 and LNKCTL2
registers (Pali Rohár)
- Clear all MSIs at setup to avoid spurious interrupts (Pali Rohár)
- Disable bus mastering when unbinding host controller driver (Pali
Rohár)
- Mask all interrupts when unbinding host controller driver (Pali
Rohár)
- Fix memory leak in host controller unbind (Pali Rohár)
- Assert PERST# when unbinding host controller driver (Pali Rohár)
- Disable link training when unbinding host controller driver (Pali
Rohár)
- Disable common PHY when unbinding host controller driver (Pali
Rohár)
- Fix resource type checking to check only IORESOURCE_MEM, not
IORESOURCE_MEM_64, which is a flavor of IORESOURCE_MEM (Pali Rohár)
Marvell MVEBU PCIe controller driver:
- Implement pci_remap_iospace() for ARM so mvebu can use
devm_pci_remap_iospace() instead of the previous ARM-specific
pci_ioremap_io() interface (Pali Rohár)
- Use the standard pci_host_probe() instead of the device-specific
mvebu_pci_host_probe() (Pali Rohár)
- Replace all uses of ARM-specific pci_ioremap_io() with the ARM
implementation of the standard pci_remap_iospace() interface and
remove pci_ioremap_io() (Pali Rohár)
- Skip initializing invalid Root Ports (Pali Rohár)
- Check for errors from pci_bridge_emul_init() (Pali Rohár)
- Ignore any bridges at non-zero function numbers (Pali Rohár)
- Return ~0 data for invalid config read size (Pali Rohár)
- Disallow mapping interrupts on emulated bridges (Pali Rohár)
- Clear Root Port Memory & I/O Space Enable and Bus Master Enable at
initialization (Pali Rohár)
- Make type bits in Root Port I/O Base register read-only (Pali
Rohár)
- Disable Root Port windows when base/limit set to invalid values
(Pali Rohár)
- Set controller to Root Complex mode (Pali Rohár)
- Set Root Port Class Code to PCI Bridge (Pali Rohár)
- Update emulated Root Port secondary bus numbers to better reflect
the actual topology (Pali Rohár)
- Add PCI_BRIDGE_CTL_BUS_RESET support to emulated Root Ports so
pci_reset_secondary_bus() can reset connected devices (Pali Rohár)
- Add PCI_EXP_DEVCTL Error Reporting Enable support to emulated Root
Ports (Pali Rohár)
- Add PCI_EXP_RTSTA PME Status bit support to emulated Root Ports
(Pali Rohár)
- Add DEVCAP2, DEVCTL2 and LNKCTL2 support to emulated Root Ports on
Armada XP and newer devices (Pali Rohár)
- Export mvebu-mbus.c symbols to allow pci-mvebu.c to be a module
(Pali Rohár)
- Add support for compiling as a module (Pali Rohár)
MediaTek PCIe controller driver:
- Assert PERST# for 100ms to allow power and clock to stabilize
(qizhong cheng)
MediaTek PCIe Gen3 controller driver:
- Disable Mediatek DVFSRC voltage request since lack of DVFSRC to
respond to the request causes failure to exit L1 PM Substate
(Jianjun Wang)
MediaTek MT7621 PCIe controller driver:
- Declare mt7621_pci_ops static (Sergio Paracuellos)
- Give pcibios_root_bridge_prepare() access to host bridge windows
(Sergio Paracuellos)
- Move MIPS I/O coherency unit setup from driver to
pcibios_root_bridge_prepare() (Sergio Paracuellos)
- Add missing MODULE_LICENSE() (Sergio Paracuellos)
- Allow COMPILE_TEST for all arches (Sergio Paracuellos)
Microsoft Hyper-V host bridge driver:
- Add hv-internal interfaces to encapsulate arch IRQ dependencies
(Sunil Muthuswamy)
- Add arm64 Hyper-V vPCI support (Sunil Muthuswamy)
Qualcomm PCIe controller driver:
- Undo PM setup in qcom_pcie_probe() error handling path (Christophe
JAILLET)
- Use __be16 type to store return value from cpu_to_be16()
(Manivannan Sadhasivam)
- Constify static dw_pcie_ep_ops (Rikard Falkeborn)
Renesas R-Car PCIe controller driver:
- Fix aarch32 abort handler so it doesn't check the wrong bus clock
before accessing the host controller (Marek Vasut)
TI Keystone PCIe controller driver:
- Add register offset for ti,syscon-pcie-id and ti,syscon-pcie-mode
DT properties (Kishon Vijay Abraham I)
MicroSemi Switchtec management driver:
- Add Gen4 automotive device IDs (Kelvin Cao)
- Declare state_names[] as static so it's not allocated and
initialized for every call (Kelvin Cao)
Host controller driver cleanups:
- Use of_device_get_match_data(), not of_match_device(), when we only
need the device data in altera, artpec6, cadence, designware-plat,
dra7xx, keystone, kirin (Fan Fei)
- Drop pointless of_device_get_match_data() cast in j721e (Bjorn
Helgaas)
- Drop redundant struct device * from j721e since struct cdns_pcie
already has one (Bjorn Helgaas)
- Rename driver structs to *_pcie in intel-gw, iproc, ls-gen4,
mediatek-gen3, microchip, mt7621, rcar-gen2, tegra194, uniphier,
xgene, xilinx, xilinx-cpm for consistency across drivers (Fan Fei)
- Fix invalid address space conversions in hisi, spear13xx (Bjorn
Helgaas)
Miscellaneous:
- Sort Intel Device IDs by value (Andy Shevchenko)
- Change Capability offsets to hex to match spec (Baruch Siach)
- Correct misspellings (Krzysztof Wilczyński)
- Terminate statement with semicolon in pci_endpoint_test.c (Ming
Wang)"
* tag 'pci-v5.17-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (151 commits)
PCI: mt7621: Allow COMPILE_TEST for all arches
PCI: mt7621: Add missing MODULE_LICENSE()
PCI: mt7621: Move MIPS setup to pcibios_root_bridge_prepare()
PCI: Let pcibios_root_bridge_prepare() access bridge->windows
PCI: mt7621: Declare mt7621_pci_ops static
PCI: brcmstb: Do not turn off WOL regulators on suspend
PCI: brcmstb: Add control of subdevice voltage regulators
PCI: brcmstb: Add mechanism to turn on subdev regulators
PCI: brcmstb: Split brcm_pcie_setup() into two funcs
dt-bindings: PCI: Add bindings for Brcmstb EP voltage regulators
dt-bindings: PCI: Correct brcmstb interrupts, interrupt-map.
PCI: brcmstb: Fix function return value handling
PCI: brcmstb: Do not use __GENMASK
PCI: brcmstb: Declare 'used' as bitmap, not unsigned long
PCI: hv: Add arm64 Hyper-V vPCI support
PCI: hv: Make the code arch neutral by adding arch specific interfaces
PCI: pciehp: Use down_read/write_nested(reset_lock) to fix lockdep errors
x86/PCI: Remove initialization of static variables to false
PCI: Use DWORD accesses for LTR, L1 SS to avoid erratum
misc: pci_endpoint_test: Terminate statement with semicolon
...
unregister after reset is clearly wrong - device
can be used while it's reset. There's an attempt to
protect against that using hwrng_removed but it
seems racy since access can be in progress
when the flag is set.
Just unregister, then reset seems simpler and cleaner.
NB: we might be able to drop hwrng_removed in a follow-up patch.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This will enable cleanups down the road.
The idea is to disable cbs, then add "flush_queued_cbs" callback
as a parameter, this way drivers can flush any work
queued after callbacks have been disabled.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20211013105226.20225-1-mst@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Here is the large set of char, misc, and other "small" driver subsystem
changes for 5.17-rc1.
Lots of different things are in here for char/misc drivers such as:
- habanalabs driver updates
- mei driver updates
- lkdtm driver updates
- vmw_vmci driver updates
- android binder driver updates
- other small char/misc driver updates
Also smaller driver subsystems have also been updated, including:
- fpga subsystem updates
- iio subsystem updates
- soundwire subsystem updates
- extcon subsystem updates
- gnss subsystem updates
- phy subsystem updates
- coresight subsystem updates
- firmware subsystem updates
- comedi subsystem updates
- mhi subsystem updates
- speakup subsystem updates
- rapidio subsystem updates
- spmi subsystem updates
- virtual driver updates
- counter subsystem updates
Too many individual changes to summarize, the shortlog contains the full
details.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc and other driver updates from Greg KH:
"Here is the large set of char, misc, and other "small" driver
subsystem changes for 5.17-rc1.
Lots of different things are in here for char/misc drivers such as:
- habanalabs driver updates
- mei driver updates
- lkdtm driver updates
- vmw_vmci driver updates
- android binder driver updates
- other small char/misc driver updates
Also smaller driver subsystems have also been updated, including:
- fpga subsystem updates
- iio subsystem updates
- soundwire subsystem updates
- extcon subsystem updates
- gnss subsystem updates
- phy subsystem updates
- coresight subsystem updates
- firmware subsystem updates
- comedi subsystem updates
- mhi subsystem updates
- speakup subsystem updates
- rapidio subsystem updates
- spmi subsystem updates
- virtual driver updates
- counter subsystem updates
Too many individual changes to summarize, the shortlog contains the
full details.
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (406 commits)
counter: 104-quad-8: Fix use-after-free by quad8_irq_handler
dt-bindings: mux: Document mux-states property
dt-bindings: ti-serdes-mux: Add defines for J721S2 SoC
counter: remove old and now unused registration API
counter: ti-eqep: Convert to new counter registration
counter: stm32-lptimer-cnt: Convert to new counter registration
counter: stm32-timer-cnt: Convert to new counter registration
counter: microchip-tcb-capture: Convert to new counter registration
counter: ftm-quaddec: Convert to new counter registration
counter: intel-qep: Convert to new counter registration
counter: interrupt-cnt: Convert to new counter registration
counter: 104-quad-8: Convert to new counter registration
counter: Update documentation for new counter registration functions
counter: Provide alternative counter registration functions
counter: stm32-timer-cnt: Convert to counter_priv() wrapper
counter: stm32-lptimer-cnt: Convert to counter_priv() wrapper
counter: ti-eqep: Convert to counter_priv() wrapper
counter: ftm-quaddec: Convert to counter_priv() wrapper
counter: intel-qep: Convert to counter_priv() wrapper
counter: microchip-tcb-capture: Convert to counter_priv() wrapper
...
Fix the compiler warning
drivers/char/agp/via-agp.c: In function 'via_configure_agp3':
drivers/char/agp/via-agp.c:131:35: warning: variable 'current_size' set but not used [-Wunused-but-set-variable]
131 | struct aper_size_info_16 *current_size;
by removing the variable.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211201114645.15384-8-tzimmermann@suse.de
Fix the compiler warning
drivers/char/agp/sworks-agp.c: In function 'serverworks_configure':
drivers/char/agp/sworks-agp.c:265:37: warning: variable 'current_size' set but not used [-Wunused-but-set-variable]
265 | struct aper_size_info_lvl2 *current_size;
by removing the variable.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211201114645.15384-7-tzimmermann@suse.de
Fix the compiler warning
drivers/char/agp/nvidia-agp.c: In function 'nvidia_tlbflush':
drivers/char/agp/nvidia-agp.c:264:22: warning: variable 'temp' set but not used [-Wunused-but-set-variable]
264 | u32 wbc_reg, temp;
by marking the temp variable with __maybe_unused. The affected readl()
is only required for flushing caches, but the returned value is not of
interest.
v2:
* declare temp as __maybe_unused (Helge)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211201114645.15384-6-tzimmermann@suse.de
Fix the compiler warning
drivers/char/agp/ati-agp.c: In function 'ati_create_page_map':
drivers/char/agp/ati-agp.c:58:16: warning: variable 'err' set but not used [-Wunused-but-set-variable]
58 | int i, err = 0;
by returing the error to the caller.
v2:
* free page in error branch (Helge)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211201114645.15384-5-tzimmermann@suse.de
Fix compiler warnings
drivers/char/agp/backend.c:68: warning: Function parameter or member 'pdev' not described in 'agp_backend_acquire'
drivers/char/agp/backend.c:93: warning: Function parameter or member 'bridge' not described in 'agp_backend_release'
by adding the necessary documentation.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211201114645.15384-4-tzimmermann@suse.de
Christophe JAILLET