The error message in __crb_relinquish_locality() mentions requestAccess
instead of Relinquish. Fix it.
Fixes: 888d867df441 ("tpm: cmd_ready command can be issued only after granting locality")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
The ftpm_mod_init() returns the driver_register() directly without checking
its return value, if driver_register() failed, the ftpm_tee_plat_driver is
not unregistered.
Fix by unregister ftpm_tee_plat_driver when driver_register() failed.
Fixes: 9f1944c23c8c ("tpm_ftpm_tee: register driver on TEE bus")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
In check_acpi_tpm2(), we get the TPM2 table just to make
sure the table is there, not used after the init, so the
acpi_put_table() should be added to release the ACPI memory.
Fixes: 4cb586a188d4 ("tpm_tis: Consolidate the platform and acpi probe flow")
Cc: stable@vger.kernel.org
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
In crb_acpi_add(), we get the TPM2 table to retrieve information
like start method, and then assign them to the priv data, so the
TPM2 table is not used after the init, should be freed, call
acpi_put_table() to fix the memory leak.
Fixes: 30fc8d138e91 ("tpm: TPM 2.0 CRB Interface")
Cc: stable@vger.kernel.org
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
The start and length of the event log area are obtained from
TPM2 or TCPA table, so we call acpi_get_table() to get the
ACPI information, but the acpi_get_table() should be coupled with
acpi_put_table() to release the ACPI memory, add the acpi_put_table()
properly to fix the memory leak.
While we are at it, remove the redundant empty line at the
end of the tpm_read_log_acpi().
Fixes: 0bfb23746052 ("tpm: Move eventlog files to a subdirectory")
Fixes: 85467f63a05c ("tpm: Add support for event log pointer found in TPM2 ACPI table")
Cc: stable@vger.kernel.org
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
The check for cancelled request depends on the VID of the chip, but
some chips share VID which shouldn't share their cancellation
behavior. This is the case for the Nuvoton NPCT75X, which should use
the default cancellation check, not the Winbond one.
To avoid changing the existing behavior, add a new flag to indicate
that the chip should use the default cancellation check and set it
for the I2C TPM2 TIS driver.
Fixes: bbc23a07b072 ("tpm: Add tpm_tis_i2c backend for tpm_tis_core")
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
The sanity check mask for TPM_INT_ENABLE register was off by 8 bits,
resulting in failure to probe if the TPM_INT_ENABLE register was a
valid value.
Fixes: bbc23a07b072 ("tpm: Add tpm_tis_i2c backend for tpm_tis_core")
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Switch the driver from legacy gpio API (that uses flat GPIO numbering)
to the newer gpiod API (which used descriptors and respects line
polarities specified in ACPI or device tree).
Because gpio handling code for SPI and I2C variants duplicates each
other it is moved into the core code for the driver.
Also, it seems that the driver never assigned tpm_dev->io_lpcpd in the
past, so gpio-based power management was most likely not working ever.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Drop support for platform data from the driver because there are no
users of st33zp24_platform_data structure in the mainline kernel.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Xu Panda <xu.panda@zte.com.cn>
The implementation of strscpy() is more robust and safer.
That's now the recommended way to copy NUL terminated strings.
Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
Signed-off-by: Yang Yang <yang.yang29@zte.com>
Message-Id: <202212051936400309332@zte.com.cn>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Currently tpm transactions are executed unconditionally in
tpm_pm_suspend() function, which may lead to races with other tpm
accessors in the system.
Specifically, the hw_random tpm driver makes use of tpm_get_random(),
and this function is called in a loop from a kthread, which means it's
not frozen alongside userspace, and so can race with the work done
during system suspend:
tpm tpm0: tpm_transmit: tpm_recv: error -52
tpm tpm0: invalid TPM_STS.x 0xff, dumping stack for forensics
CPU: 0 PID: 1 Comm: init Not tainted 6.1.0-rc5+ #135
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
Call Trace:
tpm_tis_status.cold+0x19/0x20
tpm_transmit+0x13b/0x390
tpm_transmit_cmd+0x20/0x80
tpm1_pm_suspend+0xa6/0x110
tpm_pm_suspend+0x53/0x80
__pnp_bus_suspend+0x35/0xe0
__device_suspend+0x10f/0x350
Fix this by calling tpm_try_get_ops(), which itself is a wrapper around
tpm_chip_start(), but takes the appropriate mutex.
Signed-off-by: Jan Dabros <jsd@semihalf.com>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Jason A. Donenfeld <Jason@zx2c4.com>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/all/c5ba47ef-393f-1fba-30bd-1230d1b4b592@suse.cz/
Cc: stable@vger.kernel.org
Fixes: e891db1a18bf ("tpm: turn on TPM on suspend for TPM 1.x")
[Jason: reworked commit message, added metadata]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The theory behind the jitter dance is that multiple things are poking at
the same cache line. This only works, however, if what's being poked at
is actually all in the same cache line. Ensure this is the case by
aligning the struct on the stack to the cache line size.
We can't use ____cacheline_aligned on a stack variable, because gcc
assumes 16 byte alignment when only 8 byte alignment is provided by the
kernel, which means gcc could technically do something pathological
like `(rsp & ~48) - 64`. It doesn't, but rather than risk it, just do
the stack alignment manually with PTR_ALIGN and an oversized buffer.
Fixes: 50ee7529ec45 ("random: try to actively add entropy rather than passively wait for it")
Cc: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Rather than just relying on interaction between cache lines of the timer
and the main loop, also explicitly take into account the fact that the
timer might fire at some time that's hard to predict, due to scheduling,
interrupts, or cross-CPU conditions. Mix in a cycle counter during the
firing of the timer, in addition to the existing one during the
scheduling of the timer. It can't hurt and can only help.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Rather than merely hoping that the callback gets called on another CPU,
arrange for that to actually happen, by round robining which CPU the
timer fires on. This way, on multiprocessor machines, we exacerbate
jitter by touching the same memory from multiple different cores.
There's a little bit of tricky bookkeeping involved here, because using
timer_setup_on_stack() + add_timer_on() + del_timer_sync() will result
in a use after free. See this sample code: <https://xn--4db.cc/xBdEiIKO/c>.
Instead, it's necessary to call [try_to_]del_timer_sync() before calling
add_timer_on(), so that the final call to del_timer_sync() at the end of
the function actually succeeds at making sure no handlers are running.
Cc: Sultan Alsawaf <sultan@kerneltoast.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.
Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The devnode() in struct class should not be modifying the device that is
passed into it, so mark it as a const * and propagate the function
signature changes out into all relevant subsystems that use this
callback.
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Justin Sanders <justin@coraid.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Gaignard <benjamin.gaignard@collabora.com>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: John Stultz <jstultz@google.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Sean Young <sean@mess.org>
Cc: Frank Haverkamp <haver@linux.ibm.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Xie Yongji <xieyongji@bytedance.com>
Cc: Gautam Dawar <gautam.dawar@xilinx.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Eli Cohen <elic@nvidia.com>
Cc: Parav Pandit <parav@nvidia.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: alsa-devel@alsa-project.org
Cc: dri-devel@lists.freedesktop.org
Cc: kvm@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: linux-block@vger.kernel.org
Cc: linux-input@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
del_singleshot_timer_sync() used to be an optimization for deleting timers
which are not rearmed from the timer callback function.
This optimization turned out to be broken and got mapped to
del_timer_sync() about 17 years ago.
Get rid of the undocumented indirection and use del_timer_sync() directly.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Link: https://lore.kernel.org/r/20221123201624.706987932@linutronix.de
On AmpereOne, 128 dynamic misc devices is not enough for the per-cpu
coresight_tmc devices. Switch the dynamic minors allocator to an ida and
add logic to allocate in the ranges [0..127] and [256..1048575], leaving
[128..255] for static misc devices. Dynamic allocations start from 127
growing downwards and then increasing from 256, so device numbering for the
first 128 devices remain the same as before.
Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20221114212212.9279-1-scott@os.amperecomputing.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a virtio console port is initialized, it is registered as an hvc
console using a virtual console number. If a KVM guest is started with
multiple virtio console devices, the same vtermno (or virtual console
number) can be used to allocate different hvc consoles, which leads to
various communication problems later on.
This is also reported in debugfs :
# grep vtermno /sys/kernel/debug/virtio-ports/*
/sys/kernel/debug/virtio-ports/vport1p1:console_vtermno: 1
/sys/kernel/debug/virtio-ports/vport2p1:console_vtermno: 1
/sys/kernel/debug/virtio-ports/vport3p1:console_vtermno: 2
/sys/kernel/debug/virtio-ports/vport4p1:console_vtermno: 3
Replace the next_vtermno global with an ID allocator and start the
allocation at 1 as it is today. Also recycle IDs when a console port
is removed.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20221122134643.376184-1-clg@kaod.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
@unit_mutex protects @unit from being freed, so obviously it should be
released after @unit is used, and not before.
This is a follow-up to commit 282a4b71816b ("char: xillybus: Prevent
use-after-free due to race condition") which ensures, among others, the
protection of @private_data after @unit_mutex has been released.
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Eli Billauer <eli.billauer@gmail.com>
Link: https://lore.kernel.org/r/20221117071825.3942-1-eli.billauer@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For bus-based driver, device removal is implemented as:
1 device_remove()->
2 bus->remove()->
3 driver->remove()
Driver core needs no inform from callee(bus driver) about the
result of remove callback. In that case, commit fc7a6209d571
("bus: Make remove callback return void") forces bus_type::remove
be void-returned.
Now we have the situation that both 1 & 2 of calling chain are
void-returned, so it does not make much sense for 3(driver->remove)
to return non-void to its caller.
So the basic idea behind this change is making remove() callback of
any bus-based driver to be void-returned.
This change, for itself, is for device drivers based on acpi-bus.
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Lee Jones <lee@kernel.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for drivers/platform/surface/*
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is required by vsprint, because it can't do things synchronously
from hardirq context, and it will be useful for an EFI notifier as well.
I didn't initially want to do this, but with two potential consumers
now, it seems worth it.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The probe function doesn't make use of the i2c_device_id * parameter so it
can be trivially converted.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: <20221118224540.619276-606-uwe@kleine-koenig.org>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Most hw_random devices return entropy which is assumed to be of full
quality, but driver authors don't bother setting the quality knob. Some
hw_random devices return less than full quality entropy, and then driver
authors set the quality knob. Therefore, the entropy crediting should be
opt-out rather than opt-in per-driver, to reflect the actual reality on
the ground.
For example, the two Raspberry Pi RNG drivers produce full entropy
randomness, and both EDK2 and U-Boot's drivers for these treat them as
such. The result is that EFI then uses these numbers and passes the to
Linux, and Linux credits them as boot, thereby initializing the RNG.
Yet, in Linux, the quality knob was never set to anything, and so on the
chance that Linux is booted without EFI, nothing is ever credited.
That's annoying.
The same pattern appears to repeat itself throughout various drivers. In
fact, very very few drivers have bothered setting quality=1024.
Looking at the git history of existing drivers and corresponding mailing
list discussion, this conclusion tracks. There's been a decent amount of
discussion about drivers that set quality < 1024 -- somebody read and
interepreted a datasheet, or made some back of the envelope calculation
somehow. But there's been very little, if any, discussion about most
drivers where the quality is just set to 1024 or unset (or set to 1000
when the authors misunderstood the API and assumed it was base-10 rather
than base-2); in both cases the intent was fairly clear of, "this is a
hardware random device; it's fine."
So let's invert this logic. A hw_random struct's quality knob now
controls the maximum quality a driver can produce, or 0 to specify 1024.
Then, the module-wide switch called "default_quality" is changed to
represent the maximum quality of any driver. By default it's 1024, and
the quality of any particular driver is then given by:
min(default_quality, rng->quality ?: 1024);
This way, the user can still turn this off for weird reasons (and we can
replace whatever driver-specific disabling hacks existed in the past),
yet we get proper crediting for relevant RNGs.
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, we reseed when random bytes are requested, if the current
seed is too old. Since random bytes can be requested from all contexts,
including hard IRQ, this means sometimes we wind up adding a bit of
latency to hard IRQ. This was so much of a problem on s390x that now
s390x just doesn't provide its architectural RNG from hard IRQ context,
so we miss out in that case.
Instead, let's just schedule a persistent delayed work, so that the
reseeding and potentially expensive operations will always happen from
process context, reducing unexpected latencies from hard IRQ.
This also has the nice effect of accumulating a transcript of random
inputs over time, since it means that we amass more input values. And it
should make future vDSO integration a bit easier.
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Juergen Christ <jchrist@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Rather than calling add_device_randomness(), the add_early_randomness()
function should use add_hwgenerator_randomness(), so that the early
entropy can be potentially credited, which allows for the RNG to
initialize earlier without having to wait for the kthread to come up.
This requires some minor API refactoring, by adding a `sleep_after`
parameter to add_hwgenerator_randomness(), so that we don't hit a
blocking sleep from add_early_randomness().
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The prior text was very old and made outdated references to TCP sequence
numbers, which should use one of the integer functions instead, since
batched entropy was introduced. The current way of describing the
quality of functions is just to say that it's as good as /dev/urandom,
which now all the functions are.
Fixes: f5b98461cb81 ("random: use chacha20 for get_random_int/long")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Since de492c83cae0 ("prandom: remove unused functions"),
get_random_int() no longer exists, so remove its reference from this
comment.
Fixes: de492c83cae0 ("prandom: remove unused functions")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The arch_get_random*_early() abstraction is not completely useful and
adds complexity, because it's not a given that there will be no calls to
arch_get_random*() between random_init_early(), which uses
arch_get_random*_early(), and init_cpu_features(). During that gap,
crng_reseed() might be called, which uses arch_get_random*(), since it's
mostly not init code.
Instead we can test whether we're in the early phase in
arch_get_random*() itself, and in doing so avoid all ambiguity about
where we are. Fortunately, the only architecture that currently
implements arch_get_random*_early() also has an alternatives-based cpu
feature system, one flag of which determines whether the other flags
have been initialized. This makes it possible to do the early check with
zero cost once the system is initialized.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
It's very unusual to have both a command line option and a compile time
option, and apparently that's confusing to people. Also, basically
everybody enables the compile time option now, which means people who
want to disable this wind up having to use the command line option to
ensure that anyway. So just reduce the number of moving pieces and nix
the compile time option in favor of the more versatile command line
option.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Now that we have get_random_u32_below(), it's nearly trivial to make
inline helpers to compute get_random_u32_above() and
get_random_u32_inclusive(), which will help clean up open coded loops
and manual computations throughout the tree.
One snag is that in order to make get_random_u32_inclusive() operate on
closed intervals, we have to do some (unlikely) special case handling if
get_random_u32_inclusive(0, U32_MAX) is called. The least expensive way
of doing this is actually to adjust the slowpath of
get_random_u32_below() to have its undefined 0 result just return the
output of get_random_u32(). We can make this basically free by calling
get_random_u32() before the branch, so that the branch latency gets
interleaved.
Cc: stable@vger.kernel.org # to ease future backports that use this api
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Until the very recent commits, many bounded random integers were
calculated using `get_random_u32() % max_plus_one`, which not only
incurs the price of a division -- indicating performance mostly was not
a real issue -- but also does not result in a uniformly distributed
output if max_plus_one is not a power of two. Recent commits moved to
using `prandom_u32_max(max_plus_one)`, which replaces the division with
a faster multiplication, but still does not solve the issue with
non-uniform output.
For some users, maybe this isn't a problem, and for others, maybe it is,
but for the majority of users, probably the question has never been
posed and analyzed, and nobody thought much about it, probably assuming
random is random is random. In other words, the unthinking expectation
of most users is likely that the resultant numbers are uniform.
So we implement here an efficient way of generating uniform bounded
random integers. Through use of compile-time evaluation, and avoiding
divisions as much as possible, this commit introduces no measurable
overhead. At least for hot-path uses tested, any potential difference
was lost in the noise. On both clang and gcc, code generation is pretty
small.
The new function, get_random_u32_below(), lives in random.h, rather than
prandom.h, and has a "get_random_xxx" function name, because it is
suitable for all uses, including cryptography.
In order to be efficient, we implement a kernel-specific variant of
Daniel Lemire's algorithm from "Fast Random Integer Generation in an
Interval", linked below. The kernel's variant takes advantage of
constant folding to avoid divisions entirely in the vast majority of
cases, works on both 32-bit and 64-bit architectures, and requests a
minimal amount of bytes from the RNG.
Link: https://arxiv.org/pdf/1805.10941.pdf
Cc: stable@vger.kernel.org # to ease future backports that use this api
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The intf_free() function frees the "intf" pointer so we cannot
dereference it again on the next line.
Fixes: cbb79863fc31 ("ipmi: Don't allow device module unload when in use")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Message-Id: <Y3M8xa1drZv4CToE@kili>
Cc: <stable@vger.kernel.org> # 5.5+
Signed-off-by: Corey Minyard <cminyard@mvista.com>
The driver for XillyUSB devices maintains a kref reference count on each
xillyusb_dev structure, which represents a physical device. This reference
count reaches zero when the device has been disconnected and there are no
open file descriptors that are related to the device. When this occurs,
kref_put() calls cleanup_dev(), which clears up the device's data,
including the structure itself.
However, when xillyusb_open() is called, this reference count becomes
tricky: This function needs to obtain the xillyusb_dev structure that
relates to the inode's major and minor (as there can be several such).
xillybus_find_inode() (which is defined in xillybus_class.c) is called
for this purpose. xillybus_find_inode() holds a mutex that is global in
xillybus_class.c to protect the list of devices, and releases this
mutex before returning. As a result, nothing protects the xillyusb_dev's
reference counter from being decremented to zero before xillyusb_open()
increments it on its own behalf. Hence the structure can be freed
due to a rare race condition.
To solve this, a mutex is added. It is locked by xillyusb_open() before
the call to xillybus_find_inode() and is released only after the kref
counter has been incremented on behalf of the newly opened inode. This
protects the kref reference counters of all xillyusb_dev structs from
being decremented by xillyusb_disconnect() during this time segment, as
the call to kref_put() in this function is done with the same lock held.
There is no need to hold the lock on other calls to kref_put(), because
if xillybus_find_inode() finds a struct, xillyusb_disconnect() has not
made the call to remove it, and hence not made its call to kref_put(),
which takes place afterwards. Hence preventing xillyusb_disconnect's
call to kref_put() is enough to ensure that the reference doesn't reach
zero before it's incremented by xillyusb_open().
It would have been more natural to increment the reference count in
xillybus_find_inode() of course, however this function is also called by
Xillybus' driver for PCIe / OF, which registers a completely different
structure. Therefore, xillybus_find_inode() treats these structures as
void pointers, and accordingly can't make any changes.
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Eli Billauer <eli.billauer@gmail.com>
Link: https://lore.kernel.org/r/20221030094209.65916-1-eli.billauer@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The kstrto<something>() functions have been moved from kernel.h to
kstrtox.h.
So, in order to eventually remove <linux/kernel.h> from <linux/watchdog.h>,
include the latter directly in the appropriate files.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Message-Id: <37daa028845d90ee77f1e547121a051a983fec2e.1667647002.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
The spec states that the minimum message retry time is 60ms, but it was
set to 20ms. Correct it.
Reported by: Tony Camuso <tcamuso@redhat.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
While reworking the archrandom handling, commit d349ab99eec7 ("random:
handle archrandom with multiple longs") switched to the non-early
archrandom helpers in random_init(), which broke initialization of the
entropy pool from the arm64 random generator.
Indeed at that point the arm64 CPU features, which verify that all CPUs
have compatible capabilities, are not finalized so arch_get_random_seed_longs()
is unsuccessful. Instead random_init() should use the _early functions,
which check only the boot CPU on arm64. On other architectures the
_early functions directly call the normal ones.
Fixes: d349ab99eec7 ("random: handle archrandom with multiple longs")
Cc: stable@vger.kernel.org
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
As of 1a3c7bb08826 ("PM: core: Add new *_PM_OPS macros, deprecate old
ones"), SIMPLE_DEV_PM_OPS() is deprecated in favor of
DEFINE_SIMPLE_DEV_PM_OPS(), which has the advantage that the PM callbacks
don't need to be wrapped with #ifdef CONFIG_PM or tagged with
__maybe_unused.
Convert to DEFINE_SIMPLE_DEV_PM_OPS(). No functional change intended.
Link: https://lore.kernel.org/r/20221025203852.681822-9-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
As of 1a3c7bb08826 ("PM: core: Add new *_PM_OPS macros, deprecate old
ones"), SIMPLE_DEV_PM_OPS() is deprecated in favor of
DEFINE_SIMPLE_DEV_PM_OPS(), which has the advantage that the PM callbacks
don't need to be wrapped with #ifdef CONFIG_PM or tagged with
__maybe_unused.
Convert to DEFINE_SIMPLE_DEV_PM_OPS(). No functional change intended.
Link: https://lore.kernel.org/r/20221025203852.681822-8-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
As of 1a3c7bb08826 ("PM: core: Add new *_PM_OPS macros, deprecate old
ones"), SIMPLE_DEV_PM_OPS() is deprecated in favor of
DEFINE_SIMPLE_DEV_PM_OPS(), which has the advantage that the PM callbacks
don't need to be wrapped with #ifdef CONFIG_PM or tagged with
__maybe_unused.
Convert to DEFINE_SIMPLE_DEV_PM_OPS(). No functional change intended.
Link: https://lore.kernel.org/r/20221025203852.681822-7-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Convert agpgart-nvidia from legacy PCI power management to the generic
power management framework.
Previously agpgart-nvidia used legacy PCI power management, and
agp_nvidia_suspend() and agp_nvidia_resume() were responsible for both
device-specific things and generic PCI things:
agp_nvidia_suspend
pci_save_state <-- generic PCI
pci_set_power_state(PCI_D3hot) <-- generic PCI
agp_nvidia_resume
pci_set_power_state(PCI_D0) <-- generic PCI
pci_restore_state <-- generic PCI
nvidia_configure <-- device-specific
Convert to generic power management where the PCI bus PM methods do the
generic PCI things, and the driver needs only the device-specific part,
i.e.,
suspend_devices_and_enter
dpm_suspend_start(PMSG_SUSPEND)
pci_pm_suspend # PCI bus .suspend() method
agp_nvidia_suspend <-- not needed at all; removed
suspend_enter
dpm_suspend_noirq(PMSG_SUSPEND)
pci_pm_suspend_noirq # PCI bus .suspend_noirq() method
pci_save_state <-- generic PCI
pci_prepare_to_sleep <-- generic PCI
pci_set_power_state
...
dpm_resume_end(PMSG_RESUME)
pci_pm_resume # PCI bus .resume() method
pci_restore_standard_config
pci_set_power_state(PCI_D0) <-- generic PCI
pci_restore_state <-- generic PCI
agp_nvidia_resume # driver->pm->resume
nvidia_configure <-- device-specific
Based on 0aeddbd0cb07 ("via-agp: convert to generic power management") by
Vaibhav Gupta <vaibhavgupta40@gmail.com>.
Link: https://lore.kernel.org/r/20221025203852.681822-6-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Convert agpgart-ati from legacy PCI power management to the generic power
management framework.
Previously agpgart-ati used legacy PCI power management, and
agp_ati_suspend() and agp_ati_resume() were responsible for both
device-specific things and generic PCI things like saving and restoring
config space and managing power state:
agp_ati_suspend
pci_save_state <-- generic PCI
pci_set_power_state(PCI_D3hot) <-- generic PCI
agp_ati_resume
pci_set_power_state(PCI_D0) <-- generic PCI
pci_restore_state <-- generic PCI
ati_configure <-- device-specific
With generic power management, the PCI bus PM methods do the generic PCI
things, and the driver needs only the device-specific part, i.e.,
suspend_devices_and_enter
dpm_suspend_start(PMSG_SUSPEND)
pci_pm_suspend # PCI bus .suspend() method
agp_ati_suspend <-- not needed at all; removed
suspend_enter
dpm_suspend_noirq(PMSG_SUSPEND)
pci_pm_suspend_noirq # PCI bus .suspend_noirq() method
pci_save_state <-- generic PCI
pci_prepare_to_sleep <-- generic PCI
pci_set_power_state
...
dpm_resume_end(PMSG_RESUME)
pci_pm_resume # PCI bus .resume() method
pci_restore_standard_config
pci_set_power_state(PCI_D0) <-- generic PCI
pci_restore_state <-- generic PCI
agp_ati_resume # driver->pm->resume
ati_configure <-- device-specific
Based on 0aeddbd0cb07 ("via-agp: convert to generic power management") by
Vaibhav Gupta <vaibhavgupta40@gmail.com>.
Link: https://lore.kernel.org/r/20221025203852.681822-5-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Convert agpgart-amdk7 from legacy PCI power management to the generic power
management framework.
Previously agpgart-amdk7 used legacy PCI power management, and
agp_amdk7_suspend() and agp_amdk7_resume() were responsible for both
device-specific things and generic PCI things like saving and restoring
config space and managing power state:
agp_amdk7_suspend
pci_save_state <-- generic PCI
pci_set_power_state <-- generic PCI
agp_amdk7_resume
pci_set_power_state(PCI_D0) <-- generic PCI
pci_restore_state <-- generic PCI
amd_irongate_driver.configure <-- device-specific
Convert to generic power management where the PCI bus PM methods do the
generic PCI things, and the driver needs only the device-specific part,
i.e.,
suspend_devices_and_enter
dpm_suspend_start(PMSG_SUSPEND)
pci_pm_suspend # PCI bus .suspend() method
agp_amdk7_suspend <-- not needed at all; removed
suspend_enter
dpm_suspend_noirq(PMSG_SUSPEND)
pci_pm_suspend_noirq # PCI bus .suspend_noirq() method
pci_save_state <-- generic PCI
pci_prepare_to_sleep <-- generic PCI
pci_set_power_state
...
dpm_resume_end(PMSG_RESUME)
pci_pm_resume # PCI bus .resume() method
pci_restore_standard_config
pci_set_power_state(PCI_D0) <-- generic PCI
pci_restore_state <-- generic PCI
agp_amdk7_resume # driver->pm->resume
amd_irongate_driver.configure <-- device-specific
Based on 0aeddbd0cb07 ("via-agp: convert to generic power management") by
Vaibhav Gupta <vaibhavgupta40@gmail.com>.
Link: https://lore.kernel.org/r/20221025203852.681822-4-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Convert agpgart-intel from legacy PCI power management to the generic power
management framework.
Previously agpgart-intel used legacy PCI power management, and
agp_intel_resume() was responsible for both device-specific things and
generic PCI things like saving and restoring config space and managing
power state.
In this case, agp_intel_suspend() was empty, and agp_intel_resume()
already did only device-specific things, so simply convert it to take a
struct device * instead of a struct pci_dev *.
Based on 0aeddbd0cb07 ("via-agp: convert to generic power management") by
Vaibhav Gupta <vaibhavgupta40@gmail.com>.
Link: https://lore.kernel.org/r/20221025203852.681822-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Convert agpgart-efficeon from legacy PCI power management to the generic
power management framework.
Previously agpgart-efficeon used legacy PCI power management, which means
agp_efficeon_suspend() and agp_efficeon_resume() were responsible for both
device-specific things and generic PCI things like saving and restoring
config space and managing power state.
In this case, agp_efficeon_suspend() was empty, and agp_efficeon_resume()
already did only device-specific things, so simply convert it to take a
struct device * instead of a struct pci_dev *.
Based on 0aeddbd0cb07 ("via-agp: convert to generic power management") by
Vaibhav Gupta <vaibhavgupta40@gmail.com>.
Link: https://lore.kernel.org/r/20221025203852.681822-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Dave Airlie <airlied@redhat.com>
The current code provokes some kernel-doc warnings:
drivers/char/ipmi/ipmi_msghandler.c:618: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
Signed-off-by: Bo Liu <liubo03@inspur.com>
Message-Id: <20221025060436.4372-1-liubo03@inspur.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
This fixes the following sparse warning:
sparse warnings: (new ones prefixed by >>)
>> drivers/char/ipmi/ssif_bmc.c:254:22: sparse: sparse: invalid assignment: |=
>> drivers/char/ipmi/ssif_bmc.c:254:22: sparse: left side has type restricted __poll_t
>> drivers/char/ipmi/ssif_bmc.c:254:22: sparse: right side has type int
Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver")
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/all/202210181103.ontD9tRT-lkp@intel.com/
Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
Message-Id: <20221024075956.3312552-1-quan@os.amperecomputing.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
