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This patch fixes the following build error for source file
drivers/scsi/pcmcia/sym53c500_cs.c:
In file included from ./include/linux/bug.h:5,
from ./include/linux/cpumask.h:14,
from ./include/linux/mm_types_task.h:14,
from ./include/linux/mm_types.h:5,
from ./include/linux/buildid.h:5,
from ./include/linux/module.h:14,
from drivers/scsi/pcmcia/sym53c500_cs.c:42:
drivers/scsi/pcmcia/sym53c500_cs.c: In function ‘SYM53C500_intr’:
./arch/parisc/include/asm/bug.h:28:2: error: expected expression before ‘do’
28 | do { \
| ^~
./arch/parisc/include/asm/io.h:276:20: note: in expansion of macro ‘BUG’
276 | #define outb(x, y) BUG()
| ^~~
drivers/scsi/pcmcia/sym53c500_cs.c:124:19: note: in expansion of macro ‘outb’
124 | #define REG0(x) (outb(C4_IMG, (x) + CONFIG4))
| ^~~~
drivers/scsi/pcmcia/sym53c500_cs.c:362:2: note: in expansion of macro ‘REG0’
362 | REG0(port_base);
| ^~~~
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Helge Deller <deller@gmx.de>
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There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field. Move the parisc pdc_stable sysfs code to use default_groups
field which has been the preferred way since aa30f47cf666 ("kobject: Add
support for default attribute groups to kobj_type") so that we can soon
get rid of the obsolete default_attrs field.
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Helge Deller <deller@gmx.de>
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Add a simplistic keyboard driver for usage of PDC I/O functions
with kgdb. This driver makes it possible to use KGDB with QEMU.
Signed-off-by: Helge Deller <deller@gmx.de>
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The definitions for pdc_toc_pim_11 and pdc_toc_pim_20 are wrong since they
include an entry for a hversion field which doesn't exist in the specification.
Fix this and clean up some whitespaces so that the whole file will be in
sync with it's copy in the SeaBIOS-hppa sources.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.16
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This patch adds two new LWS routines - lws_atomic_xchg and lws_atomic_store.
These are simpler than the CAS routines. Currently, we use the CAS
routines for atomic stores. This is inefficient since it requires
both winning the spinlock and a successful CAS operation.
Change has been tested on c8000 and rp3440.
In v2, I moved the code to disble/enable page faults inside the spinlocks.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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The parisc architecture lacks general hardware support for compare and swap.
Particularly for userspace, it is difficult to implement software atomic
support. Page faults in critical regions can cause processes to sleep and
block the forward progress of other processes. Thus, it is essential that
page faults be disabled in critical regions. For performance reasons, we
also need to disable external interrupts in critical regions.
In order to do this, we need a mechanism to trigger COW breaks outside the
critical region. Fortunately, parisc has the "stbys,e" instruction. When
the leftmost byte of a word is addressed, this instruction triggers all
the exceptions of a normal store but it does not write to memory. Thus,
we can use it to trigger COW breaks outside the critical region without
modifying the data that is to be updated atomically.
COW breaks occur randomly. So even if we have priviously executed a "stbys,e"
instruction, we still need to disable pagefaults around the critical region.
If a fault occurs in the critical region, we return -EAGAIN. I had to add
a wrapper around _arch_futex_atomic_op_inuser() as I found in testing that
returning -EAGAIN caused problems for some processes even though it is
listed as a possible return value.
The patch implements the above. The code no longer attempts to sleep with
interrupts disabled and I haven't seen any stalls with the change.
I have attempted to merge common code and streamline the fast path. In the
futex code, we only compute the spinlock address once.
I eliminated some debug code in the original CAS routine that just made the
flow more complicated.
I don't clip the arguments when called from wide mode. As a result, the LWS
routines should work when called from 64-bit processes.
I defined TASK_PAGEFAULT_DISABLED offset for use in the lws_pagefault_disable
and lws_pagefault_enable macros.
Since we now disable interrupts on the gateway page where necessary, it
might be possible to allow processes to be scheduled when they are on the
gateway page.
Change has been tested on c8000 and rp3440. It improves glibc build and test
time by about 10%.
In v2, I removed the lws_atomic_xchg and and lws_atomic_store calls. I
also removed the bug fixes that were not directly related to this patch.
In v3, I removed the code to force interruptions from
arch_futex_atomic_op_inuser(). It is always called with page faults
disabled, so this code had no effect.
In v4, I fixed a typo in depi_safe line.
In v5, I moved the code to disable/enable page faults inside the spinlocks.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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In debugging kernel panics, I believe it is useful to know what type
of page fault caused the termination. "Bad Address" is too vague.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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It is dangerous to call faulthandler_disabled() when user_mode(regs)
is true. The task pagefault_disabled counter is racy and it is not
updated atomically on parisc. As a result, calling faulthandler_disabled()
may cause erroneous termination.
We now handle execption fixups and termination when user_mode(regs) is
false in handle_interruption(). Thus, we can just remove the
faulthandler_disabled() check from do_page_fault().
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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Use register r29 instead of register r8 to signal faults when accessing
user memory. In case of faults, the fixup routine will store -EFAULT in
this register.
This change saves up to 752 bytes on a 32bit kernel, partly because the
compiler doesn't need to save and restore the old r8 value on the stack.
bloat-o-meter results for usage with r29 register:
add/remove: 0/0 grow/shrink: 23/86 up/down: 228/-980 (-752)
bloat-o-meter results for usage with r28 register:
add/remove: 0/0 grow/shrink: 28/83 up/down: 296/-956 (-660)
Signed-off-by: Helge Deller <deller@gmx.de>
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In handle_interruption(), we call faulthandler_disabled() to check whether the
fault handler is not disabled. If the fault handler is disabled, we immediately
call do_page_fault(). It then calls faulthandler_disabled(). If disabled,
do_page_fault() attempts to fixup the exception by jumping to no_context:
no_context:
if (!user_mode(regs) && fixup_exception(regs)) {
return;
}
parisc_terminate("Bad Address (null pointer deref?)", regs, code, address);
Apart from the error messages, the two blocks of code perform the same
function.
We can avoid two calls to faulthandler_disabled() by a simple revision
to the code in handle_interruption().
Note: I didn't try to fix the formatting of this code block.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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While working on the rewrite to the light-weight syscall and futex code, I
experimented with using a hash index based on the user physical address of
atomic variable. This exposed two problems with the lpa and lpa_user defines.
Because of the copy instruction, the pa argument needs to be an early clobber
argument. This prevents gcc from allocating the va and pa arguments to the same
register.
Secondly, the lpa instruction can cause a page fault so we need to catch
exceptions.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Fixes: 116d753308cf ("parisc: Use lpa instruction to load physical addresses in driver code")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.2+
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The depi instruction is similar to the extru instruction on 64-bit machines.
It leaves the most-significant 32 bits of the target register in an undefined
state. On 64-bit machines, the macro uses depdi to perform safe deposits in
the least-significant 32 bits.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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Fix the following build warning:
Documentation/networking/devlink/mlx5.rst:13: WARNING: Error parsing content block for the "list-table" directive:
+uniform two-level bullet list expected, but row 2 does not contain the same number of items as row 1 (2 vs 3).
...
Add the missing item in the first row.
Fixes: 0844fa5f7b89 ("net/mlx5: Let user configure io_eq_size param")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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The rep legacy RQ completion handling was missing the appropriate
handling of error CQEs (dump the CQE and queue a recover work), fix it
by calling trigger_report() when needed.
Since all CQE handling flows do the exact same error CQE handling,
extract it to a common helper function.
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Aya Levin <ayal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Remove redundant and trivial error logging when trying to
offload mirred device with unsupported devices.
Using OVS could hit those a lot and the errors are still
logged in extack.
Signed-off-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Rearrange the code and use cqe_mode_to_period_mode() helper.
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Feature dependencies should be resolved in fix features rather than in
set features flow. Move the check that disables HW-GRO in case CQE
compression is enabled from set_feature_hw_gro() to
mlx5e_fix_features().
Signed-off-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Remove redundant space when constructing the feature's enum. Validate
against the indented enum value.
Fixes: 6c72cb05d4b8 ("net/mlx5e: Use bitmap field for profile features")
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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When using libvirt to passthrough VF to VM it will always set the VF vlan
to 0 even if user didn’t request it, this will cause libvirt to fail to
boot in case the PF isn't eswitch owner.
Example of such case is the DPU host PF which isn't eswitch manager, so
any attempt to passthrough VF of it using libvirt will fail.
Fix it by not returning error in case set VF vlan is called with vid 0.
Signed-off-by: Maor Dickman <maord@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Add FEC counters' statistics of corrected_blocks and
uncorrectable_blocks, along with their lanes via ethtool.
HW supports corrected_blocks and uncorrectable_blocks counters both for
RS-FEC mode and FC-FEC mode. In FC mode these counters are accumulated
per lane, while in RS mode the correction method crosses lanes, thus
only total corrected_blocks and uncorrectable_blocks are reported in
this mode.
Signed-off-by: Lama Kayal <lkayal@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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log_max_qp in driver's default profile #2 was set to 18, but FW actually
supports 17 at the most - a situation that led to the concerning print
when the driver is loaded:
"log_max_qp value in current profile is 18, changing to HCA capabaility
limit (17)"
The expected behavior from mlx5_profile #2 is to match the maximum FW
capability in regards to log_max_qp. Thus, log_max_qp in profile #2 is
initialized to a defined static value (0xff) - which basically means that
when loading this profile, log_max_qp value will be what the currently
installed FW supports at most.
Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Currently all SFs are using the same CPUs. Spreading SF over CPUs, in
round-robin manner, in order to achieve better distribution of the SFs
over available CPUs.
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Currently IRQs are requested one by one. To balance spreading IRQs
among cpus using such scheme requires remembering cpu mask for the
cpus used for a given device. This complicates the IRQ allocation
scheme in subsequent patch.
Hence, prepare the code for bulk IRQs allocation. This enables
spreading IRQs among cpus in subsequent patch.
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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The downstream patches add more functionality to irq_pool_affinity.
Move the irq_pool_affinity logic to a new file in order to ease the
coding and maintenance of it.
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Move affinity binding of the IRQ to irq_request function in order to
bind the IRQ before inserting it to the xarray.
After this change, the IRQ is ready for use when inserted to the xarray.
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Currently, IRQ layer have a separate flow for ctrl and comp IRQs, and
the distinction between ctrl and comp IRQs is done in the IRQ layer.
In order to ease the coding and maintenance of the IRQ layer,
introduce a new API for requesting control IRQs -
mlx5_ctrl_irq_request(struct mlx5_core_dev *dev).
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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Callers of this functions ignore its return value, as reported by
Wang Qing, in one of the return paths, it returns positive values.
Since return value is ignored anyways, void out the return type of the
function.
Reported-by: Wang Qing <wangqing@vivo.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
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At the moment, urandom_read() (used for /dev/urandom) resets crng_init_cnt
to zero when it is called at crng_init<2. This is inconsistent: We do it
for /dev/urandom reads, but not for the equivalent
getrandom(GRND_INSECURE).
(And worse, as Jason pointed out, we're only doing this as long as
maxwarn>0.)
crng_init_cnt is only read in crng_fast_load(); it is relevant at
crng_init==0 for determining when to switch to crng_init==1 (and where in
the RNG state array to write).
As far as I understand:
- crng_init==0 means "we have nothing, we might just be returning the same
exact numbers on every boot on every machine, we don't even have
non-cryptographic randomness; we should shove every bit of entropy we
can get into the RNG immediately"
- crng_init==1 means "well we have something, it might not be
cryptographic, but at least we're not gonna return the same data every
time or whatever, it's probably good enough for TCP and ASLR and stuff;
we now have time to build up actual cryptographic entropy in the input
pool"
- crng_init==2 means "this is supposed to be cryptographically secure now,
but we'll keep adding more entropy just to be sure".
The current code means that if someone is pulling data from /dev/urandom
fast enough at crng_init==0, we'll keep resetting crng_init_cnt, and we'll
never make forward progress to crng_init==1. It seems to be intended to
prevent an attacker from bruteforcing the contents of small individual RNG
inputs on the way from crng_init==0 to crng_init==1, but that's misguided;
crng_init==1 isn't supposed to provide proper cryptographic security
anyway, RNG users who care about getting secure RNG output have to wait
until crng_init==2.
This code was inconsistent, and it probably made things worse - just get
rid of it.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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RDRAND is not fast. RDRAND is actually quite slow. We've known this for
a while, which is why functions like get_random_u{32,64} were converted
to use batching of our ChaCha-based CRNG instead.
Yet CRNG extraction still includes a call to RDRAND, in the hot path of
every call to get_random_bytes(), /dev/urandom, and getrandom(2).
This call to RDRAND here seems quite superfluous. CRNG is already
extracting things based on a 256-bit key, based on good entropy, which
is then reseeded periodically, updated, backtrack-mutated, and so
forth. The CRNG extraction construction is something that we're already
relying on to be secure and solid. If it's not, that's a serious
problem, and it's unlikely that mixing in a measly 32 bits from RDRAND
is going to alleviate things.
And in the case where the CRNG doesn't have enough entropy yet, we're
already initializing the ChaCha key row with RDRAND in
crng_init_try_arch_early().
Removing the call to RDRAND improves performance on an i7-11850H by
370%. In other words, the vast majority of the work done by
extract_crng() prior to this commit was devoted to fetching 32 bits of
RDRAND.
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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Previously, the ChaCha constants for the primary pool were only
initialized in crng_initialize_primary(), called by rand_initialize().
However, some randomness is actually extracted from the primary pool
beforehand, e.g. by kmem_cache_create(). Therefore, statically
initialize the ChaCha constants for the primary pool.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <linux-crypto@vger.kernel.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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Rather than an awkward combination of ifdefs and __maybe_unused, we can
ensure more source gets parsed, regardless of the configuration, by
using IS_ENABLED for the CONFIG_NUMA conditional code. This makes things
cleaner and easier to follow.
I've confirmed that on !CONFIG_NUMA, we don't wind up with excess code
by accident; the generated object file is the same.
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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We print out "crng init done" for !TRUST_CPU, so we should also print
out the same for TRUST_CPU.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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If we're trusting bootloader randomness, crng_fast_load() is called by
add_hwgenerator_randomness(), which sets us to crng_init==1. However,
usually it is only called once for an initial 64-byte push, so bootloader
entropy will not mix any bytes into the input pool. So it's conceivable
that crng_init==1 when crng_initialize_primary() is called later, but
then the input pool is empty. When that happens, the crng state key will
be overwritten with extracted output from the empty input pool. That's
bad.
In contrast, if we're not trusting bootloader randomness, we call
crng_slow_load() *and* we call mix_pool_bytes(), so that later
crng_initialize_primary() isn't drawing on nothing.
In order to prevent crng_initialize_primary() from extracting an empty
pool, have the trusted bootloader case mirror that of the untrusted
bootloader case, mixing the input into the pool.
[linux@dominikbrodowski.net: rewrite commit message]
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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When crng_fast_load() is called by add_hwgenerator_randomness(), we
currently will advance to crng_init==1 once we've acquired 64 bytes, and
then throw away the rest of the buffer. Usually, that is not a problem:
When add_hwgenerator_randomness() gets called via EFI or DT during
setup_arch(), there won't be any IRQ randomness. Therefore, the 64 bytes
passed by EFI exactly matches what is needed to advance to crng_init==1.
Usually, DT seems to pass 64 bytes as well -- with one notable exception
being kexec, which hands over 128 bytes of entropy to the kexec'd kernel.
In that case, we'll advance to crng_init==1 once 64 of those bytes are
consumed by crng_fast_load(), but won't continue onward feeding in bytes
to progress to crng_init==2. This commit fixes the issue by feeding
any leftover bytes into the next phase in add_hwgenerator_randomness().
[linux@dominikbrodowski.net: rewrite commit message]
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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If the bootloader supplies sufficient material and crng_reseed() is called
very early on, but not too early that wqs aren't available yet, then we
might transition to crng_init==2 before rand_initialize()'s call to
crng_initialize_primary() made. Then, when crng_initialize_primary() is
called, if we're trusting the CPU's RDRAND instructions, we'll
needlessly reinitialize the RNG and emit a message about it. This is
mostly harmless, as numa_crng_init() will allocate and then free what it
just allocated, and excessive calls to invalidate_batched_entropy()
aren't so harmful. But it is funky and the extra message is confusing,
so avoid the re-initialization all together by checking for crng_init <
2 in crng_initialize_primary(), just as we already do in crng_reseed().
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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Currently, if CONFIG_RANDOM_TRUST_BOOTLOADER is enabled, multiple calls
to add_bootloader_randomness() are broken and can cause a NULL pointer
dereference, as noted by Ivan T. Ivanov. This is not only a hypothetical
problem, as qemu on arm64 may provide bootloader entropy via EFI and via
devicetree.
On the first call to add_hwgenerator_randomness(), crng_fast_load() is
executed, and if the seed is long enough, crng_init will be set to 1.
On subsequent calls to add_bootloader_randomness() and then to
add_hwgenerator_randomness(), crng_fast_load() will be skipped. Instead,
wait_event_interruptible() and then credit_entropy_bits() will be called.
If the entropy count for that second seed is large enough, that proceeds
to crng_reseed().
However, both wait_event_interruptible() and crng_reseed() depends
(at least in numa_crng_init()) on workqueues. Therefore, test whether
system_wq is already initialized, which is a sufficient indicator that
workqueue_init_early() has progressed far enough.
If we wind up hitting the !system_wq case, we later want to do what
would have been done there when wqs are up, so set a flag, and do that
work later from the rand_initialize() call.
Reported-by: Ivan T. Ivanov <iivanov@suse.de>
Fixes: 18b915ac6b0a ("efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness")
Cc: stable@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
[Jason: added crng_need_done state and related logic.]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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By using `char` instead of `unsigned char`, certain platforms will sign
extend the byte when `w = rol32(*bytes++, input_rotate)` is called,
meaning that bit 7 is overrepresented when mixing. This isn't a real
problem (unless the mixer itself is already broken) since it's still
invertible, but it's not quite correct either. Fix this by using an
explicit unsigned type.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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This commit addresses one of the lower hanging fruits of the RNG: its
usage of SHA1.
BLAKE2s is generally faster, and certainly more secure, than SHA1, which
has [1] been [2] really [3] very [4] broken [5]. Additionally, the
current construction in the RNG doesn't use the full SHA1 function, as
specified, and allows overwriting the IV with RDRAND output in an
undocumented way, even in the case when RDRAND isn't set to "trusted",
which means potential malicious IV choices. And its short length means
that keeping only half of it secret when feeding back into the mixer
gives us only 2^80 bits of forward secrecy. In other words, not only is
the choice of hash function dated, but the use of it isn't really great
either.
This commit aims to fix both of these issues while also keeping the
general structure and semantics as close to the original as possible.
Specifically:
a) Rather than overwriting the hash IV with RDRAND, we put it into
BLAKE2's documented "salt" and "personal" fields, which were
specifically created for this type of usage.
b) Since this function feeds the full hash result back into the
entropy collector, we only return from it half the length of the
hash, just as it was done before. This increases the
construction's forward secrecy from 2^80 to a much more
comfortable 2^128.
c) Rather than using the raw "sha1_transform" function alone, we
instead use the full proper BLAKE2s function, with finalization.
This also has the advantage of supplying 16 bytes at a time rather than
SHA1's 10 bytes, which, in addition to having a faster compression
function to begin with, means faster extraction in general. On an Intel
i7-11850H, this commit makes initial seeding around 131% faster.
BLAKE2s itself has the nice property of internally being based on the
ChaCha permutation, which the RNG is already using for expansion, so
there shouldn't be any issue with newness, funkiness, or surprising CPU
behavior, since it's based on something already in use.
[1] https://eprint.iacr.org/2005/010.pdf
[2] https://www.iacr.org/archive/crypto2005/36210017/36210017.pdf
[3] https://eprint.iacr.org/2015/967.pdf
[4] https://shattered.io/static/shattered.pdf
[5] https://www.usenix.org/system/files/sec20-leurent.pdf
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
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>
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In preparation for using blake2s in the RNG, we change the way that it
is wired-in to the build system. Instead of using ifdefs to select the
right symbol, we use weak symbols. And because ARM doesn't need the
generic implementation, we make the generic one default only if an arch
library doesn't need it already, and then have arch libraries that do
need it opt-in. So that the arch libraries can remain tristate rather
than bool, we then split the shash part from the glue code.
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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_extract_crng() does plain loads of crng->init_time and
crng_global_init_time, which causes undefined behavior if
crng_reseed() and RNDRESEEDCRNG modify these corrently.
Use READ_ONCE() and WRITE_ONCE() to make the behavior defined.
Don't fix the race on crng->init_time by protecting it with crng->lock,
since it's not a problem for duplicate reseedings to occur. I.e., the
lockless access with READ_ONCE() is fine.
Fixes: d848e5f8e1eb ("random: add new ioctl RNDRESEEDCRNG")
Fixes: e192be9d9a30 ("random: replace non-blocking pool with a Chacha20-based CRNG")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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extract_crng() and crng_backtrack_protect() load crng_node_pool with a
plain load, which causes undefined behavior if do_numa_crng_init()
modifies it concurrently.
Fix this by using READ_ONCE(). Note: as per the previous discussion
https://lore.kernel.org/lkml/20211219025139.31085-1-ebiggers@kernel.org/T/#u,
READ_ONCE() is believed to be sufficient here, and it was requested that
it be used here instead of smp_load_acquire().
Also change do_numa_crng_init() to set crng_node_pool using
cmpxchg_release() instead of mb() + cmpxchg(), as the former is
sufficient here but is more lightweight.
Fixes: 1e7f583af67b ("random: make /dev/urandom scalable for silly userspace programs")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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The __IRQF_TIMER bit from the flags argument was used in
add_interrupt_randomness() to distinguish the timer interrupt from other
interrupts. This is no longer the case.
Remove the flags argument from __handle_irq_event_percpu().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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Since commit
ee3e00e9e7101 ("random: use registers from interrupted code for CPU's w/o a cycle counter")
the irq_flags argument is no longer used.
Remove unused irq_flags.
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: linux-hyperv@vger.kernel.org
Cc: x86@kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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The section at the top of random.c which documents the input functions
available does not document add_hwgenerator_randomness() which might lead
a reader to overlook it. Add a brief note about it.
Signed-off-by: Mark Brown <broonie@kernel.org>
[Jason: reorganize position of function in doc comment and also document
add_bootloader_randomness() while we're at it.]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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This is handy not just for humans, but also so that the 0-day bot can
automatically test posted mailing list patches against the right tree.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
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The second parameter of bpf_d_path() can only accept writable
memories. Rdonly_mem obtained from bpf_per_cpu_ptr() can not
be passed into bpf_d_path for modification. This patch adds
a selftest to verify this behavior.
Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220106205525.2116218-1-haoluo@google.com
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This adds documention for:
- bpf_map_delete_batch()
- bpf_map_lookup_batch()
- bpf_map_lookup_and_delete_batch()
- bpf_map_update_batch()
This also updates the public API for the `keys` parameter
of `bpf_map_delete_batch()`, and both the
`keys` and `values` parameters of `bpf_map_update_batch()`
to be constants.
Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220106201304.112675-1-grantseltzer@gmail.com
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Three minor tracing fixes:
- Fix missing prototypes in sample module for direct functions
- Fix check of valid buffer in get_trace_buf()
- Fix annotations of percpu pointers"
* tag 'trace-v5.16-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Tag trace_percpu_buffer as a percpu pointer
tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()
ftrace/samples: Add missing prototypes direct functions
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After commit dc26532aed0a ("cgroup: rstat: punt root-level optimization to
individual controllers"), each rstat on updated_children list has its
->updated_next not NULL.
This means we can remove the check on ->updated_next, if we make sure
the subtree from @root is on list, which could be done by checking
updated_next for root.
tj: Coding style fixes.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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PT_REGS*() macro on some architectures force-cast struct pt_regs to
other types (user_pt_regs, etc) and might drop volatile modifiers, if any.
Volatile isn't really required as pt_regs value isn't supposed to change
during the BPF program run, so this is correct behavior.
But progs/loop3.c relies on that volatile modifier to ensure that loop
is preserved. Fix loop3.c by declaring i and sum variables as volatile
instead. It preserves the loop and makes the test pass on all
architectures (including s390x which is currently broken).
Fixes: 3cc31d794097 ("libbpf: Normalize PT_REGS_xxx() macro definitions")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220106205156.955373-1-andrii@kernel.org
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