The sp804 is currently only user selectable if COMPILE_TEST, this was
done by commit dfc82faad725 ("clocksource/drivers/sp804: Add
COMPILE_TEST to CONFIG_ARM_TIMER_SP804") in order to avoid it being
spuriously offered on platforms that won't have the hardware since it's
generally only seen on Arm based platforms. This config is overly
restrictive, while platforms that rely on the SP804 do select it in
their Kconfig there are others such as the Arm fast models which have a
SP804 available but currently unused by Linux. Relax the dependency to
allow it to be user selectable on arm and arm64 to avoid surprises and
in case someone comes up with a use for extra timer hardware.
Fixes: dfc82faad725 ("clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804") Reported-by: Ross Burton <ross.burton@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-vexpress-sp804-v3-1-0a2d3f7883e4@kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
During testing of the preceding changes, I noticed that in some cases,
current->kcsan_ctx.in_flat_atomic remained true until task exit. This is
obviously wrong, because _all_ accesses for the given task will be
treated as atomic, resulting in false negatives i.e. missed data races.
Debugging led to fs/dcache.c, where we can see this usage of seqlock:
do {
seq = read_seqbegin(&rename_lock);
dentry = __d_lookup(parent, name);
if (dentry)
break;
} while (read_seqretry(&rename_lock, seq));
[...]
As can be seen, read_seqretry() is never called if dentry != NULL;
consequently, current->kcsan_ctx.in_flat_atomic will never be reset to
false by read_seqretry().
Give up on the wrong assumption of "assume closing read_seqretry()", and
rely on the already-present annotations in read_seqcount_begin/retry().
Fixes: 88ecd153be95 ("seqlock, kcsan: Add annotations for KCSAN") Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20241104161910.780003-6-elver@google.com Signed-off-by: Sasha Levin <sashal@kernel.org>
While fuzzing an arm64 kernel, Alexander Potapenko reported:
| BUG: KCSAN: data-race in ktime_get_mono_fast_ns / timekeeping_update
|
| write to 0xffffffc082e74248 of 56 bytes by interrupt on cpu 0:
| update_fast_timekeeper kernel/time/timekeeping.c:430 [inline]
| timekeeping_update+0x1d8/0x2d8 kernel/time/timekeeping.c:768
| timekeeping_advance+0x9e8/0xb78 kernel/time/timekeeping.c:2344
| update_wall_time+0x18/0x38 kernel/time/timekeeping.c:2360
| [...]
|
| read to 0xffffffc082e74258 of 8 bytes by task 5260 on cpu 1:
| __ktime_get_fast_ns kernel/time/timekeeping.c:372 [inline]
| ktime_get_mono_fast_ns+0x88/0x174 kernel/time/timekeeping.c:489
| init_srcu_struct_fields+0x40c/0x530 kernel/rcu/srcutree.c:263
| init_srcu_struct+0x14/0x20 kernel/rcu/srcutree.c:311
| [...]
|
| value changed: 0x000002f875d33266 -> 0x000002f877416866
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 1 UID: 0 PID: 5260 Comm: syz.2.7483 Not tainted 6.12.0-rc3-dirty #78
This is a false positive data race between a seqcount latch writer and a reader
accessing stale data. Since its introduction, KCSAN has never understood the
seqcount_latch interface (due to being unannotated).
Unlike the regular seqlock interface, the seqcount_latch interface for latch
writers never has had a well-defined critical section, making it difficult to
teach tooling where the critical section starts and ends.
Introduce an instrumentable (non-raw) seqcount_latch interface, with
which we can clearly denote writer critical sections. This both helps
readability and tooling like KCSAN to understand when the writer is done
updating all latch copies.
Fixes: 88ecd153be95 ("seqlock, kcsan: Add annotations for KCSAN") Reported-by: Alexander Potapenko <glider@google.com> Co-developed-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Signed-off-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20241104161910.780003-4-elver@google.com Signed-off-by: Sasha Levin <sashal@kernel.org>
do {
seq = raw_read_seqcount_latch(&latch->seq);
...
} while (read_seqcount_latch_retry(&latch->seq, seq));
which is asymmetric in the raw_ department, and sure enough,
read_seqcount_latch_retry() includes (explicit) instrumentation where
raw_read_seqcount_latch() does not.
This inconsistency becomes a problem when trying to use it from
noinstr code. As such, fix it by renaming and re-implementing
raw_read_seqcount_latch_retry() without the instrumentation.
Specifically the instrumentation in question is kcsan_atomic_next(0)
in do___read_seqcount_retry(). Loosing this annotation is not a
problem because raw_read_seqcount_latch() does not pass through
kcsan_atomic_next(KCSAN_SEQLOCK_REGION_MAX).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V Link: https://lore.kernel.org/r/20230519102715.233598176@infradead.org
Stable-dep-of: 5c1806c41ce0 ("kcsan, seqlock: Support seqcount_latch_t") Signed-off-by: Sasha Levin <sashal@kernel.org>
The details about the handling of the "normal" values were moved
to the _msecs_to_jiffies() helpers in commit ca42aaf0c861 ("time:
Refactor msecs_to_jiffies"). However, the same commit still mentioned
__msecs_to_jiffies() in the added documentation.
Thus point to _msecs_to_jiffies() instead.
Fixes: ca42aaf0c861 ("time: Refactor msecs_to_jiffies") Signed-off-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20241025110141.157205-2-ojeda@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
The ahash_init functions may return fails. The ahash_hmac_init should
not return ok when ahash_init returns error. For an example, ahash_init
will return -ENOMEM when allocation memory is error.
During modprobe:
1. In igen6_probe(), igen6_pvt will be allocated with kzalloc()
2. In igen6_register_mci(), mci->pvt_info will point to
&igen6_pvt->imc[mc]
During rmmod:
1. In mci_release() in edac_mc.c, it will kfree(mci->pvt_info)
2. In igen6_remove(), it will kfree(igen6_pvt);
Fix this issue by setting mci->pvt_info to NULL to avoid the double
kfree.
Fixes: 10590a9d4f23 ("EDAC/igen6: Add EDAC driver for Intel client SoCs using IBECC") Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219360 Signed-off-by: Orange Kao <orange@aiven.io> Signed-off-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/r/20241104124237.124109-2-orange@aiven.io Signed-off-by: Sasha Levin <sashal@kernel.org>
The while loop breaks in the first run because of incorrect
if condition. It also causes the statements after the if to
appear dead.
Fix this by changing the condition from if(timeout--) to
if(!timeout--).
This bug was reported by Coverity Scan.
Report:
CID 1600859: (#1 of 1): Logically dead code (DEADCODE)
dead_error_line: Execution cannot reach this statement: udelay(30UL);
Fixes: 9e2c7d99941d ("crypto: cavium - Add Support for Octeon-tx CPT Engine") Signed-off-by: Everest K.C. <everestkc@everestkc.com.np> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
Since commit 8f4f68e788c3 ("crypto: pcrypt - Fix hungtask for
PADATA_RESET"), the pcrypt encryption and decryption operations return
-EAGAIN when the CPU goes online or offline. In alg_test(), a WARN is
generated when pcrypt_aead_decrypt() or pcrypt_aead_encrypt() returns
-EAGAIN, the unnecessary panic will occur when panic_on_warn set 1.
Fix this issue by calling crypto layer directly without parallelization
in that case.
Fixes: 8f4f68e788c3 ("crypto: pcrypt - Fix hungtask for PADATA_RESET") Signed-off-by: Yi Yang <yiyang13@huawei.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
Fix undefined behavior caused by left-shifting a negative value in the
expression:
cap_high ^ (1 << (bad_data_bit - 32))
The variable bad_data_bit ranges from 0 to 63. When it is less than 32,
bad_data_bit - 32 becomes negative, and left-shifting by a negative
value in C is undefined behavior.
Fix this by combining cap_high and cap_low into a 64-bit variable.
[ bp: Massage commit message, simplify error bits handling. ]
Fixes: ea2eb9a8b620 ("EDAC, fsl-ddr: Separate FSL DDR driver from MPC85xx") Signed-off-by: Priyanka Singh <priyanka.singh@nxp.com> Signed-off-by: Li Yang <leoyang.li@nxp.com> Signed-off-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20241016-imx95_edac-v3-3-86ae6fc2756a@nxp.com Signed-off-by: Sasha Levin <sashal@kernel.org>
Since user space can start interacting with a new thermal zone as soon
as device_register() called by thermal_zone_device_register_with_trips()
returns, it is better to initialize the thermal zone before calling
device_register() on it.
Fixes: d0df264fbd3c ("thermal/core: Remove pointless thermal_zone_device_reset() function") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://patch.msgid.link/3336146.44csPzL39Z@rjwysocki.net Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Resetting the service arbiter config can cause potential issues
related to response ordering and ring flow control check in the
event of AER or device hang. This is because it results in changing
the default response ring size from 32 bytes to 16 bytes. The service
arbiter config reset also disables response ring flow control check.
Thus, by removing this reset we can prevent the service arbiter from
being configured inappropriately, which leads to undesired device
behaviour in the event of errors.
The 64-bit argument for the "get DIMM info" SMC call consists of mem_ctrl_idx
left-shifted 16 bits and OR-ed with DIMM index. With mem_ctrl_idx defined as
32-bits wide the left-shift operation truncates the upper 16 bits of
information during the calculation of the SMC argument.
The mem_ctrl_idx stack variable must be defined as 64-bits wide to prevent any
potential integer overflow, i.e. loss of data from upper 16 bits.
Fixes: 82413e562ea6 ("EDAC, mellanox: Add ECC support for BlueField DDR4") Signed-off-by: David Thompson <davthompson@nvidia.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shravan Kumar Ramani <shravankr@nvidia.com> Link: https://lore.kernel.org/r/20240930151056.10158-1-davthompson@nvidia.com Signed-off-by: Sasha Levin <sashal@kernel.org>
When platform_device_register_full() returns error, the gsmi_init() returns
without unregister gsmi_driver_info, fix by add missing
platform_driver_unregister() when platform_device_register_full() failed.
Fixes: 8942b2d5094b ("gsmi: Add GSMI commands to log S0ix info") Signed-off-by: Yuan Can <yuancan@huawei.com> Acked-by: Brian Norris <briannorris@chromium.org> Link: https://lore.kernel.org/r/20241015131344.20272-1-yuancan@huawei.com Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The type of the last parameter given to devm_add_action_or_reset() is
"struct caam_drv_private *", but in caam_qi_shutdown(), it is casted to
"struct device *".
Pass the correct parameter to devm_add_action_or_reset() so that the
resources are released as expected.
Fixes: f414de2e2fff ("crypto: caam - use devres to de-initialize QI") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
Devices block sizes may change. One of these cases is a loop device by
using ioctl LOOP_SET_BLOCK_SIZE.
While this may cause other issues like IO being rejected, in the case of
hfsplus, it will allocate a block by using that size and potentially write
out-of-bounds when hfsplus_read_wrapper calls hfsplus_submit_bio and the
latter function reads a different io_size.
Using a new min_io_size initally set to sb_min_blocksize works for the
purposes of the original fix, since it will be set to the max between
HFSPLUS_SECTOR_SIZE and the first seen logical block size. We still use the
max between HFSPLUS_SECTOR_SIZE and min_io_size in case the latter is not
initialized.
Tested by mounting an hfsplus filesystem with loop block sizes 512, 1024
and 4096.
The produced KASAN report before the fix looks like this:
Fixes: 6596528e391a ("hfsplus: ensure bio requests are not smaller than the hardware sectors") Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com> Link: https://lore.kernel.org/r/20241107114109.839253-1-cascardo@igalia.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
In case of error in gtdt_parse_timer_block() invalid 'gtdt_frame'
will be used in 'do {} while (i-- >= 0 && gtdt_frame--);' statement block
because do{} block will be executed even if 'i == 0'.
Adjust error handling procedure by replacing 'i-- >= 0' with 'i-- > 0'.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: a712c3ed9b8a ("acpi/arm64: Add memory-mapped timer support in GTDT driver") Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru> Acked-by: Hanjun Guo <guohanjun@huawei.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Aleksandr Mishin <amishin@t-argos.ru> Link: https://lore.kernel.org/r/20240827101239.22020-1-amishin@t-argos.ru Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Commit be2881824ae9 ("arm64/build: Assert for unwanted sections")
introduced an assertion to ensure that the .data.rel.ro section does
not exist.
However, this check does not work when CONFIG_LTO_CLANG is enabled,
because .data.rel.ro matches the .data.[0-9a-zA-Z_]* pattern in the
DATA_MAIN macro.
Commit a38eaa07a0ce ("m68k/mvme147: config.c - Remove unused
functions"), removed the console functionality for the mvme147 instead
of wiring it up to an early console. Put the console write function
back and wire it up like mvme16x does so it's possible to see Linux boot
on this fine hardware once more.
Sometime long ago the m68k IRQ code was refactored and the interrupt
numbers for SCSI controller on this board ended up wrong, and it hasn't
worked since.
The PCC adds 0x40 to the vector for its interrupts so they end up in
the user interrupt range. Hence, the kernel number should be the kernel
offset for user interrupt range + the PCC interrupt number.
The HMB descriptor table is sized to the maximum number of descriptors
that could be used for a given device, but __nvme_alloc_host_mem could
break out of the loop earlier on memory allocation failure and end up
using less descriptors than planned for, which leads to an incorrect
size passed to dma_free_coherent.
In practice this was not showing up because the number of descriptors
tends to be low and the dma coherent allocator always allocates and
frees at least a page.
Fixes: 87ad72a59a38 ("nvme-pci: implement host memory buffer support") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The initramfs filename field is defined in
Documentation/driver-api/early-userspace/buffer-format.rst as:
37 cpio_file := ALGN(4) + cpio_header + filename + "\0" + ALGN(4) + data
...
55 ============= ================== =========================
56 Field name Field size Meaning
57 ============= ================== =========================
...
70 c_namesize 8 bytes Length of filename, including final \0
When extracting an initramfs cpio archive, the kernel's do_name() path
handler assumes a zero-terminated path at @collected, passing it
directly to filp_open() / init_mkdir() / init_mknod().
If a specially crafted cpio entry carries a non-zero-terminated filename
and is followed by uninitialized memory, then a file may be created with
trailing characters that represent the uninitialized memory. The ability
to create an initramfs entry would imply already having full control of
the system, so the buffer overrun shouldn't be considered a security
vulnerability.
Append the output of the following bash script to an existing initramfs
and observe any created /initramfs_test_fname_overrunAA* path. E.g.
./reproducer.sh | gzip >> /myinitramfs
It's easiest to observe non-zero uninitialized memory when the output is
gzipped, as it'll overflow the heap allocated @out_buf in __gunzip(),
rather than the initrd_start+initrd_size block.
---- reproducer.sh ----
nilchar="A" # change to "\0" to properly zero terminate / pad
magic="070701"
ino=1
mode=$(( 0100777 ))
uid=0
gid=0
nlink=1
mtime=1
filesize=0
devmajor=0
devminor=1
rdevmajor=0
rdevminor=0
csum=0
fname="initramfs_test_fname_overrun"
namelen=$(( ${#fname} + 1 )) # plus one to account for terminator
When MIPS_FP_SUPPORT is disabled, __sanitize_fcr31() is defined as
nothing, which triggers a gcc warning:
In file included from kernel/sched/core.c:79:
kernel/sched/core.c: In function 'context_switch':
./arch/mips/include/asm/switch_to.h:114:39: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
114 | __sanitize_fcr31(next); \
| ^
kernel/sched/core.c:5316:9: note: in expansion of macro 'switch_to'
5316 | switch_to(prev, next, prev);
| ^~~~~~~~~
Fix this by providing an empty body for __sanitize_fcr31() like one is
defined for __mips_mt_fpaff_switch_to().
Fixes: 36a498035bd2 ("MIPS: Avoid FCSR sanitization when CONFIG_MIPS_FP_SUPPORT=n") Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com> Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
loop_init() is calling loop_add() after __register_blkdev() succeeds and
is ignoring disk_add() failure from loop_add(), for loop_add() failure
is not fatal and successfully created disks are already visible to
bdev_open().
brd_init() is currently calling brd_alloc() before __register_blkdev()
succeeds and is releasing successfully created disks when brd_init()
returns an error. This can cause UAF for the latter two case:
case 1:
T1:
modprobe brd
brd_init
brd_alloc(0) // success
add_disk
disk_scan_partitions
bdev_file_open_by_dev // alloc file
fput // won't free until back to userspace
brd_alloc(1) // failed since mem alloc error inject
// error path for modprobe will release code segment
// back to userspace
__fput
blkdev_release
bdev_release
blkdev_put_whole
bdev->bd_disk->fops->release // fops is freed now, UAF!
case 2:
T1: T2:
modprobe brd
brd_init
brd_alloc(0) // success
open(/dev/ram0)
brd_alloc(1) // fail
// error path for modprobe
If brd_alloc() from brd_probe() is called before brd_alloc() from
brd_init() is called, module loading will fail with -EEXIST error.
To close this race, call __register_blkdev() just before leaving
brd_init().
Then, we can remove brd_devices_mutex mutex, for brd_device list
will no longer be accessed concurrently.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/6b074af7-c165-4fab-b7da-8270a4f6f6cd@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 826cc42adf44 ("brd: defer automatic disk creation until module initialization succeeds") Signed-off-by: Sasha Levin <sashal@kernel.org>
Starting with commit 2297791c92d0 ("s390/cio: dont unregister
subchannel from child-drivers"), CIO does not unregister subchannels
when the attached device is invalid or unavailable. Instead, it
allows subchannels to exist without a connected device. However, if
the DNV value is 0, such as, when all the CHPIDs of a subchannel are
configured in standby state, the subchannel is unregistered, which
contradicts the current subchannel specification.
Update the logic so that subchannels are not unregistered based
on the DNV value. Also update the SCHIB information even if the
DNV bit is zero.
Suggested-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com> Fixes: 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers") Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
When checking MTE tags, we print some diagnostic messages when the tests
fail. Some variables uses there are "longs", however we only use "%x"
for the format specifier.
Update the format specifiers to "%lx", to match the variable types they
are supposed to print.
Fixes: f3b2a26ca78d ("kselftest/arm64: Verify mte tag inclusion via prctl") Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240816153251.2833702-9-andre.przywara@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
AMD does not have the requirement for a synchronization barrier when
acccessing a certain group of MSRs. Do not incur that unnecessary
penalty there.
There will be a CPUID bit which explicitly states that a MFENCE is not
needed. Once that bit is added to the APM, this will be extended with
it.
While at it, move to processor.h to avoid include hell. Untangling that
file properly is a matter for another day.
Some notes on the performance aspect of why this is relevant, courtesy
of Kishon VijayAbraham <Kishon.VijayAbraham@amd.com>:
On a AMD Zen4 system with 96 cores, a modified ipi-bench[1] on a VM
shows x2AVIC IPI rate is 3% to 4% lower than AVIC IPI rate. The
ipi-bench is modified so that the IPIs are sent between two vCPUs in the
same CCX. This also requires to pin the vCPU to a physical core to
prevent any latencies. This simulates the use case of pinning vCPUs to
the thread of a single CCX to avoid interrupt IPI latency.
In order to avoid run-to-run variance (for both x2AVIC and AVIC), the
below configurations are done:
1) Disable Power States in BIOS (to prevent the system from going to
lower power state)
2) Run the system at fixed frequency 2500MHz (to prevent the system
from increasing the frequency when the load is more)
With the above configuration:
*) Performance measured using ipi-bench for AVIC:
Average Latency: 1124.98ns [Time to send IPI from one vCPU to another vCPU]
Cumulative throughput: 42.6759M/s [Total number of IPIs sent in a second from
48 vCPUs simultaneously]
*) Performance measured using ipi-bench for x2AVIC:
Average Latency: 1172.42ns [Time to send IPI from one vCPU to another vCPU]
Cumulative throughput: 40.9432M/s [Total number of IPIs sent in a second from
48 vCPUs simultaneously]
From above, x2AVIC latency is ~4% more than AVIC. However, the expectation is
x2AVIC performance to be better or equivalent to AVIC. Upon analyzing
the perf captures, it is observed significant time is spent in
weak_wrmsr_fence() invoked by x2apic_send_IPI().
With the fix to skip weak_wrmsr_fence()
*) Performance measured using ipi-bench for x2AVIC:
Average Latency: 1117.44ns [Time to send IPI from one vCPU to another vCPU]
Cumulative throughput: 42.9608M/s [Total number of IPIs sent in a second from
48 vCPUs simultaneously]
Comparing the performance of x2AVIC with and without the fix, it can be seen
the performance improves by ~4%.
Performance captured using an unmodified ipi-bench using the 'mesh-ipi' option
with and without weak_wrmsr_fence() on a Zen4 system also showed significant
performance improvement without weak_wrmsr_fence(). The 'mesh-ipi' option ignores
CCX or CCD and just picks random vCPU.
Average throughput (10 iterations) with weak_wrmsr_fence(),
Cumulative throughput: 4933374 IPI/s
Average throughput (10 iterations) without weak_wrmsr_fence(),
Cumulative throughput: 6355156 IPI/s
On an NVMe namespace that does not support metadata, it is possible to
send an IO command with metadata through io-passthru. This allows issues
like [1] to trigger in the completion code path.
nvme_map_user_request() doesn't check if the namespace supports metadata
before sending it forward. It also allows admin commands with metadata to
be processed as it ignores metadata when bdev == NULL and may report
success.
Reject an IO command with metadata when the NVMe namespace doesn't
support it and reject an admin command if it has metadata.
Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Puranjay Mohan <pjy@amazon.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Anuj Gupta <anuj20.g@samsung.com> Signed-off-by: Keith Busch <kbusch@kernel.org>
[ Move the changes from nvme_map_user_request() to nvme_submit_user_cmd()
to make it work on 5.15 ] Signed-off-by: Hagar Hemdan <hagarhem@amazon.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
ReparseDataLength is sum of the InodeType size and DataBuffer size.
So to get DataBuffer size it is needed to subtract InodeType's size from
ReparseDataLength.
Function cifs_strndup_from_utf16() is currentlly accessing buf->DataBuffer
at position after the end of the buffer because it does not subtract
InodeType size from the length. Fix this problem and correctly subtract
variable len.
Member InodeType is present only when reparse buffer is large enough. Check
for ReparseDataLength before accessing InodeType to prevent another invalid
memory access.
Major and minor rdev values are present also only when reparse buffer is
large enough. Check for reparse buffer size before calling reparse_mkdev().
Fixes: d5ecebc4900d ("smb3: Allow query of symlinks stored as reparse points") Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
[use variable name symlink_buf, the other buf->InodeType accesses are
not used in current version so skip] Signed-off-by: Mahmoud Adam <mngyadam@amazon.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Any idle task corresponding to an offline CPU is in an RCU Tasks Trace
quiescent state. This commit causes rcu_tasks_trace_postscan() to ignore
idle tasks for offline CPUs, which it can do safely due to CPU-hotplug
operations being disabled.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <kafai@fb.com> Cc: KP Singh <kpsingh@kernel.org> Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Accessing `mr_table->mfc_cache_list` is protected by an RCU lock. In the
following code flow, the RCU read lock is not held, causing the
following error when `RCU_PROVE` is not held. The same problem might
show up in the IPv6 code path.
6.12.0-rc5-kbuilder-01145-gbac17284bdcb #33 Tainted: G E N
-----------------------------
net/ipv4/ipmr_base.c:313 RCU-list traversed in non-reader section!!
This is not a problem per see, since the RTNL lock is held here, so, it
is safe to iterate in the list without the RCU read lock, as suggested
by Eric.
To alleviate the concern, modify the code to use
list_for_each_entry_rcu() with the RTNL-held argument.
The annotation will raise an error only if RTNL or RCU read lock are
missing during iteration, signaling a legitimate problem, otherwise it
will avoid this false positive.
This will solve the IPv6 case as well, since ip6mr_rtm_dumproute() calls
this function as well.
Fix the physical address calculation of the following to get smp working
on xip kernels.
- secondary_data needed for secondary cpu bootup.
- secondary_startup address passed through psci.
- identity mapped code region needed for enabling mmu for secondary cpus.
Signed-off-by: Harith George <harith.g@alifsemi.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
seq_printf is costy, on a system with n CPUs, reading /proc/softirqs
would yield 10*n decimal values, and the extra cost parsing format string
grows linearly with number of cpus. Replace seq_printf with
seq_put_decimal_ull_width have significant performance improvement.
On an 8CPUs system, reading /proc/softirqs show ~40% performance
gain with this patch.
Signed-off-by: David Wang <00107082@163.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
This patch checks if div is less than or equal to zero (div <= 0). If
div is zero or negative, the function returns -EINVAL, ensuring the
division operation is safe to perform.
This patch checks if div is less than or equal to zero (div <= 0). If
div is zero or negative, the function returns -EINVAL, ensuring the
division operation (*prate / div) is safe to perform.
Some Alienware devices have a key that locks/unlocks the Meta key. This
key triggers a WMI event that should be ignored by the kernel, as it's
handled by internally the firmware.
There is no known way of changing this default behavior. The firmware
would lock/unlock the Meta key, regardless of how the event is handled.
Tested on an Alienware x15 R1.
Signed-off-by: Kurt Borja <kuurtb@gmail.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Pali Rohár <pali@kernel.org> Link: https://lore.kernel.org/r/20241031154441.6663-2-kuurtb@gmail.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Which is triggered after dell-wmi driver fails to initialize on
Alienware systems, as it depends on dell-smbios.
This effectively extends dell-wmi, dell-smbios and dcdbas support to
Alienware devices, that might share some features of the SMBIOS intereface
calling interface with other Dell products.
Tested on an Alienware X15 R1.
Signed-off-by: Kurt Borja <kuurtb@gmail.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Pali Rohár <pali@kernel.org> Link: https://lore.kernel.org/r/20241031154023.6149-2-kuurtb@gmail.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently, RK809's BUCK3 regulator is modelled in the driver as a
configurable regulator with 0.5-2.4V voltage range. But the voltage
setting is not actually applied, because when bit 6 of
PMIC_POWER_CONFIG register is set to 0 (default), BUCK3 output voltage
is determined by the external feedback resistor. Fix this, by setting
bit 6 when voltage selection is set. Existing users which do not
specify voltage constraints in their device trees will not be affected
by this change, since no voltage setting is applied in those cases,
and bit 6 is not enabled.
node_to_amd_nb() is defined to NULL in non-AMD configs:
drivers/platform/x86/amd/hsmp/plat.c: In function 'init_platform_device':
drivers/platform/x86/amd/hsmp/plat.c:165:68: error: dereferencing 'void *' pointer [-Werror]
165 | sock->root = node_to_amd_nb(i)->root;
| ^~
drivers/platform/x86/amd/hsmp/plat.c:165:68: error: request for member 'root' in something not a structure or union
Users of the interface who also allow COMPILE_TEST will cause the above build
error so provide an inline stub to fix that.
Infinix ZERO BOOK 13 has a 2+2 speaker system which isn't probed correctly.
This patch adds a quirk with the proper pin connections.
Also The mic in this laptop suffers too high gain resulting in mostly
fan noise being recorded,
This patch Also limit mic boost.
HW Probe for device; https://linux-hardware.org/?probe=a2e892c47b
When running watchdog-test with 'make run_tests', the watchdog-test will
be terminated by a timeout signal(SIGTERM) due to the test timemout.
And then, a system reboot would happen due to watchdog not stop. see
the dmesg as below:
```
[ 1367.185172] watchdog: watchdog0: watchdog did not stop!
```
Fix it by registering more signals(including SIGTERM) in watchdog-test,
where its signal handler will stop the watchdog.
After that
# timeout 1 ./watchdog-test
Watchdog Ticking Away!
.
Stopping watchdog ticks...
This patch adds support for another Lenovo Mini dock 0x17EF:0x3098 to the
r8152 driver. The device has been tested on NixOS, hotplugging and sleep
included.
Signed-off-by: Benjamin Große <ste3ls@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20241020174128.160898-1-ste3ls@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When starting the suspend flow, HOST_D3_START triggers an _async_
firmware dump collection for debugging purposes. The async worker
may race with suspend flow and fail to get NIC access, resulting in
the following warning:
"Timeout waiting for hardware access (CSR_GP_CNTRL 0xffffffff)"
Fix this by switching to the sync version to ensure the dump
completes before proceeding with the suspend flow, avoiding
potential race issues.
Some old Bay Trail tablets which shipped with Android as factory OS
have the SST/LPE audio engine described by an ACPI device with a
HID (Hardware-ID) of LPE0F28 instead of 80860F28.
Add support for this. Note this uses a new sst_res_info for just
the LPE0F28 case because it has a different layout for the IO-mem ACPI
resources then the 80860F28.
An example of a tablet which needs this is the Vexia EDU ATLA 10 tablet,
which has been distributed to schools in the Spanish Andalucía region.
The Vexia Edu Atla 10 tablet mostly uses the BYTCR tablet defaults,
but as happens on more models it is using IN1 instead of IN3 for
its internal mic and JD_SRC_JD2_IN4N instead of JD_SRC_JD1_IN4P
for jack-detection.
Add a DMI quirk for this to fix the internal-mic and jack-detection.
On some x86 Bay Trail tablets which shipped with Android as factory OS,
the DSDT is so broken that the codec needs to be manually instantatiated
by the special x86-android-tablets.ko "fixup" driver for cases like this.
This means that the codec-dev cannot be retrieved through its ACPI fwnode,
add support to the bytcr_rt5640 machine driver for such manually
instantiated rt5640 i2c_clients.
An example of a tablet which needs this is the Vexia EDU ATLA 10 tablet,
which has been distributed to schools in the Spanish Andalucía region.
It is not safe to call filemap_fdatawrite_range() from
nfs_async_write_reschedule_io(), since we're often calling from a page
reclaim context. Just let fsync() redrive the writeback for us.
The mmap_region() function is somewhat terrifying, with spaghetti-like
control flow and numerous means by which issues can arise and incomplete
state, memory leaks and other unpleasantness can occur.
A large amount of the complexity arises from trying to handle errors late
in the process of mapping a VMA, which forms the basis of recently
observed issues with resource leaks and observable inconsistent state.
Taking advantage of previous patches in this series we move a number of
checks earlier in the code, simplifying things by moving the core of the
logic into a static internal function __mmap_region().
Doing this allows us to perform a number of checks up front before we do
any real work, and allows us to unwind the writable unmap check
unconditionally as required and to perform a CONFIG_DEBUG_VM_MAPLE_TREE
validation unconditionally also.
We move a number of things here:
1. We preallocate memory for the iterator before we call the file-backed
memory hook, allowing us to exit early and avoid having to perform
complicated and error-prone close/free logic. We carefully free
iterator state on both success and error paths.
2. The enclosing mmap_region() function handles the mapping_map_writable()
logic early. Previously the logic had the mapping_map_writable() at the
point of mapping a newly allocated file-backed VMA, and a matching
mapping_unmap_writable() on success and error paths.
We now do this unconditionally if this is a file-backed, shared writable
mapping. If a driver changes the flags to eliminate VM_MAYWRITE, however
doing so does not invalidate the seal check we just performed, and we in
any case always decrement the counter in the wrapper.
We perform a debug assert to ensure a driver does not attempt to do the
opposite.
3. We also move arch_validate_flags() up into the mmap_region()
function. This is only relevant on arm64 and sparc64, and the check is
only meaningful for SPARC with ADI enabled. We explicitly add a warning
for this arch if a driver invalidates this check, though the code ought
eventually to be fixed to eliminate the need for this.
With all of these measures in place, we no longer need to explicitly close
the VMA on error paths, as we place all checks which might fail prior to a
call to any driver mmap hook.
This eliminates an entire class of errors, makes the code easier to reason
about and more robust.
Link: https://lkml.kernel.org/r/6e0becb36d2f5472053ac5d544c0edfe9b899e25.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Mark Brown <broonie@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently MTE is permitted in two circumstances (desiring to use MTE
having been specified by the VM_MTE flag) - where MAP_ANONYMOUS is
specified, as checked by arch_calc_vm_flag_bits() and actualised by
setting the VM_MTE_ALLOWED flag, or if the file backing the mapping is
shmem, in which case we set VM_MTE_ALLOWED in shmem_mmap() when the mmap
hook is activated in mmap_region().
The function that checks that, if VM_MTE is set, VM_MTE_ALLOWED is also
set is the arm64 implementation of arch_validate_flags().
Unfortunately, we intend to refactor mmap_region() to perform this check
earlier, meaning that in the case of a shmem backing we will not have
invoked shmem_mmap() yet, causing the mapping to fail spuriously.
It is inappropriate to set this architecture-specific flag in general mm
code anyway, so a sensible resolution of this issue is to instead move the
check somewhere else.
We resolve this by setting VM_MTE_ALLOWED much earlier in do_mmap(), via
the arch_calc_vm_flag_bits() call.
This is an appropriate place to do this as we already check for the
MAP_ANONYMOUS case here, and the shmem file case is simply a variant of
the same idea - we permit RAM-backed memory.
This requires a modification to the arch_calc_vm_flag_bits() signature to
pass in a pointer to the struct file associated with the mapping, however
this is not too egregious as this is only used by two architectures anyway
- arm64 and parisc.
So this patch performs this adjustment and removes the unnecessary
assignment of VM_MTE_ALLOWED in shmem_mmap().
[akpm@linux-foundation.org: fix whitespace, per Catalin] Link: https://lkml.kernel.org/r/ec251b20ba1964fb64cf1607d2ad80c47f3873df.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andreas Larsson <andreas@gaisler.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Incorrect invocation of VMA callbacks when the VMA is no longer in a
consistent state is bug prone and risky to perform.
With regards to the important vm_ops->close() callback We have gone to
great lengths to try to track whether or not we ought to close VMAs.
Rather than doing so and risking making a mistake somewhere, instead
unconditionally close and reset vma->vm_ops to an empty dummy operations
set with a NULL .close operator.
We introduce a new function to do so - vma_close() - and simplify existing
vms logic which tracked whether we needed to close or not.
This simplifies the logic, avoids incorrect double-calling of the .close()
callback and allows us to update error paths to simply call vma_close()
unconditionally - making VMA closure idempotent.
Link: https://lkml.kernel.org/r/28e89dda96f68c505cb6f8e9fc9b57c3e9f74b42.1730224667.git.lorenzo.stoakes@oracle.com Fixes: deb0f6562884 ("mm/mmap: undo ->mmap() when arch_validate_flags() fails") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reported-by: Jann Horn <jannh@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Patch series "fix error handling in mmap_region() and refactor
(hotfixes)", v4.
mmap_region() is somewhat terrifying, with spaghetti-like control flow and
numerous means by which issues can arise and incomplete state, memory
leaks and other unpleasantness can occur.
A large amount of the complexity arises from trying to handle errors late
in the process of mapping a VMA, which forms the basis of recently
observed issues with resource leaks and observable inconsistent state.
This series goes to great lengths to simplify how mmap_region() works and
to avoid unwinding errors late on in the process of setting up the VMA for
the new mapping, and equally avoids such operations occurring while the
VMA is in an inconsistent state.
The patches in this series comprise the minimal changes required to
resolve existing issues in mmap_region() error handling, in order that
they can be hotfixed and backported. There is additionally a follow up
series which goes further, separated out from the v1 series and sent and
updated separately.
This patch (of 5):
After an attempted mmap() fails, we are no longer in a situation where we
can safely interact with VMA hooks. This is currently not enforced,
meaning that we need complicated handling to ensure we do not incorrectly
call these hooks.
We can avoid the whole issue by treating the VMA as suspect the moment
that the file->f_ops->mmap() function reports an error by replacing
whatever VMA operations were installed with a dummy empty set of VMA
operations.
We do so through a new helper function internal to mm - mmap_file() -
which is both more logically named than the existing call_mmap() function
and correctly isolates handling of the vm_op reassignment to mm.
All the existing invocations of call_mmap() outside of mm are ultimately
nested within the call_mmap() from mm, which we now replace.
It is therefore safe to leave call_mmap() in place as a convenience
function (and to avoid churn). The invokers are:
Additional active subflows - i.e. created by the in kernel path
manager - are included into the subflow list before starting the
3whs.
A racing recvmsg() spooling data received on an already established
subflow would unconditionally call tcp_cleanup_rbuf() on all the
current subflows, potentially hitting a divide by zero error on
the newly created ones.
Explicitly check that the subflow is in a suitable state before
invoking tcp_cleanup_rbuf().
Fixes: c76c6956566f ("mptcp: call tcp_cleanup_rbuf on subflows") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/02374660836e1b52afc91966b7535c8c5f7bafb0.1731060874.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Conflicts in protocol.c, because commit f410cbea9f3d ("tcp: annotate
data-races around tp->window_clamp") has not been backported to this
version. The conflict is easy to resolve, because only the context is
different, but not the line to modify. ] Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The error flow in nfsd4_copy() calls cleanup_async_copy(), which
already decrements nn->pending_async_copies.
Reported-by: Olga Kornievskaia <okorniev@redhat.com> Fixes: aadc3bbea163 ("NFSD: Limit the number of concurrent async COPY operations") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure the refcount and async_copies fields are initialized early.
cleanup_async_copy() will reference these fields if an error occurs
in nfsd4_copy(). If they are not correctly initialized, at the very
least, a refcount underflow occurs.
Reported-by: Olga Kornievskaia <okorniev@redhat.com> Fixes: aadc3bbea163 ("NFSD: Limit the number of concurrent async COPY operations") Reviewed-by: Jeff Layton <jlayton@kernel.org> Tested-by: Olga Kornievskaia <okorniev@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nothing appears to limit the number of concurrent async COPY
operations that clients can start. In addition, AFAICT each async
COPY can copy an unlimited number of 4MB chunks, so can run for a
long time. Thus IMO async COPY can become a DoS vector.
Add a restriction mechanism that bounds the number of concurrent
background COPY operations. Start simple and try to be fair -- this
patch implements a per-namespace limit.
An async COPY request that occurs while this limit is exceeded gets
NFS4ERR_DELAY. The requesting client can choose to send the request
again after a delay or fall back to a traditional read/write style
copy.
If there is need to make the mechanism more sophisticated, we can
visit that in future patches.
Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://nvd.nist.gov/vuln/detail/CVE-2024-49974 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, when NFSD handles an asynchronous COPY, it returns a
zero write verifier, relying on the subsequent CB_OFFLOAD callback
to pass the write verifier and a stable_how4 value to the client.
However, if the CB_OFFLOAD never arrives at the client (for example,
if a network partition occurs just as the server sends the
CB_OFFLOAD operation), the client will never receive this verifier.
Thus, if the client sends a follow-up COMMIT, there is no way for
the client to assess the COMMIT result.
The usual recovery for a missing CB_OFFLOAD is for the client to
send an OFFLOAD_STATUS operation, but that operation does not carry
a write verifier in its result. Neither does it carry a stable_how4
value, so the client /must/ send a COMMIT in this case -- which will
always fail because currently there's still no write verifier in the
COPY result.
Thus the server needs to return a normal write verifier in its COPY
result even if the COPY operation is to be performed asynchronously.
If the server recognizes the callback stateid in subsequent
OFFLOAD_STATUS operations, then obviously it has not restarted, and
the write verifier the client received in the COPY result is still
valid and can be used to assess a COMMIT of the copied data, if one
is needed.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to origin/linux-5.15.y ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It turns out that the Allwinner A100/A133 SoC only supports 8K DMA
blocks (13 bits wide), for both the SD/SDIO and eMMC instances.
And while this alone would make a trivial fix, the H616 falls back to
the A100 compatible string, so we have to now match the H616 compatible
string explicitly against the description advertising 64K DMA blocks.
As the A100 is now compatible with the D1 description, let the A100
compatible string point to that block instead, and introduce an explicit
match against the H616 string, pointing to the old description.
Also remove the redundant setting of clk_delays to NULL on the way.
D1's MMC controllers are unique in that they have the DMA address shift
(like A100) with a 13-bit descriptor size field (like sun4i). Add the
compatible and parameters for this new variant.
Signed-off-by: Samuel Holland <samuel@sholland.org> Acked-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220203015112.12008-2-samuel@sholland.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Stable-dep-of: 85b580afc2c2 ("mmc: sunxi-mmc: Fix A100 compatible description") Signed-off-by: Sasha Levin <sashal@kernel.org>
Wait for the command transmission to be completed in the DSI transfer
function polling for the dc_start bit to go back to idle state after the
transmission is started.
This is documented in the datasheet and failures to do so lead to
commands corruption.
The commit 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages
bigger than 4K") increased the max_req_size, even for 4K pages, causing
various issues:
- Panic booting the kernel/rootfs from an SD card on Rockchip RK3566
- Panic booting the kernel/rootfs from an SD card on StarFive JH7100
- "swiotlb buffer is full" and data corruption on StarFive JH7110
At this stage no fix have been found, so it's probably better to just
revert the change.
When using the "block:block_dirty_buffer" tracepoint, mark_buffer_dirty()
may cause a NULL pointer dereference, or a general protection fault when
KASAN is enabled.
This happens because, since the tracepoint was added in
mark_buffer_dirty(), it references the dev_t member bh->b_bdev->bd_dev
regardless of whether the buffer head has a pointer to a block_device
structure.
In the current implementation, nilfs_grab_buffer(), which grabs a buffer
to read (or create) a block of metadata, including b-tree node blocks,
does not set the block device, but instead does so only if the buffer is
not in the "uptodate" state for each of its caller block reading
functions. However, if the uptodate flag is set on a folio/page, and the
buffer heads are detached from it by try_to_free_buffers(), and new buffer
heads are then attached by create_empty_buffers(), the uptodate flag may
be restored to each buffer without the block device being set to
bh->b_bdev, and mark_buffer_dirty() may be called later in that state,
resulting in the bug mentioned above.
Fix this issue by making nilfs_grab_buffer() always set the block device
of the super block structure to the buffer head, regardless of the state
of the buffer's uptodate flag.
For a really damaged superblock, the value of 'i_super.s_blocksize_bits'
may exceed the maximum possible shift for an underlying 'int'. So add an
extra check whether the aforementioned field represents the valid block
size, which is 512 bytes, 1K, 2K, or 4K.
Link: https://lkml.kernel.org/r/20241106092100.2661330-1-dmantipov@yandex.ru Fixes: ccd979bdbce9 ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem") Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Reported-by: syzbot+56f7cd1abe4b8e475180@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=56f7cd1abe4b8e475180 Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Patch series "nilfs2: fix null-ptr-deref bugs on block tracepoints".
This series fixes null pointer dereference bugs that occur when using
nilfs2 and two block-related tracepoints.
This patch (of 2):
It has been reported that when using "block:block_touch_buffer"
tracepoint, touch_buffer() called from __nilfs_get_folio_block() causes a
NULL pointer dereference, or a general protection fault when KASAN is
enabled.
This happens because since the tracepoint was added in touch_buffer(), it
references the dev_t member bh->b_bdev->bd_dev regardless of whether the
buffer head has a pointer to a block_device structure. In the current
implementation, the block_device structure is set after the function
returns to the caller.
Here, touch_buffer() is used to mark the folio/page that owns the buffer
head as accessed, but the common search helper for folio/page used by the
caller function was optimized to mark the folio/page as accessed when it
was reimplemented a long time ago, eliminating the need to call
touch_buffer() here in the first place.
So this solves the issue by eliminating the touch_buffer() call itself.
Hide KVM's pt_mode module param behind CONFIG_BROKEN, i.e. disable support
for virtualizing Intel PT via guest/host mode unless BROKEN=y. There are
myriad bugs in the implementation, some of which are fatal to the guest,
and others which put the stability and health of the host at risk.
For guest fatalities, the most glaring issue is that KVM fails to ensure
tracing is disabled, and *stays* disabled prior to VM-Enter, which is
necessary as hardware disallows loading (the guest's) RTIT_CTL if tracing
is enabled (enforced via a VMX consistency check). Per the SDM:
If the logical processor is operating with Intel PT enabled (if
IA32_RTIT_CTL.TraceEn = 1) at the time of VM entry, the "load
IA32_RTIT_CTL" VM-entry control must be 0.
On the host side, KVM doesn't validate the guest CPUID configuration
provided by userspace, and even worse, uses the guest configuration to
decide what MSRs to save/load at VM-Enter and VM-Exit. E.g. configuring
guest CPUID to enumerate more address ranges than are supported in hardware
will result in KVM trying to passthrough, save, and load non-existent MSRs,
which generates a variety of WARNs, ToPA ERRORs in the host, a potential
deadlock, etc.
Fixes: f99e3daf94ff ("KVM: x86: Add Intel PT virtualization work mode") Cc: stable@vger.kernel.org Cc: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Tested-by: Adrian Hunter <adrian.hunter@intel.com>
Message-ID: <20241101185031.1799556-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When getting the current VPID, e.g. to emulate a guest TLB flush, return
vpid01 if L2 is running but with VPID disabled, i.e. if VPID is disabled
in vmcs12. Architecturally, if VPID is disabled, then the guest and host
effectively share VPID=0. KVM emulates this behavior by using vpid01 when
running an L2 with VPID disabled (see prepare_vmcs02_early_rare()), and so
KVM must also treat vpid01 as the current VPID while L2 is active.
Unconditionally treating vpid02 as the current VPID when L2 is active
causes KVM to flush TLB entries for vpid02 instead of vpid01, which
results in TLB entries from L1 being incorrectly preserved across nested
VM-Enter to L2 (L2=>L1 isn't problematic, because the TLB flush after
nested VM-Exit flushes vpid01).
The bug manifests as failures in the vmx_apicv_test KVM-Unit-Test, as KVM
incorrectly retains TLB entries for the APIC-access page across a nested
VM-Enter.
Opportunisticaly add comments at various touchpoints to explain the
architectural requirements, and also why KVM uses vpid01 instead of vpid02.
All credit goes to Chao, who root caused the issue and identified the fix.
Link: https://lore.kernel.org/all/ZwzczkIlYGX+QXJz@intel.com Fixes: 2b4a5a5d5688 ("KVM: nVMX: Flush current VPID (L1 vs. L2) for KVM_REQ_TLB_FLUSH_GUEST") Cc: stable@vger.kernel.org Cc: Like Xu <like.xu.linux@gmail.com> Debugged-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Tested-by: Chao Gao <chao.gao@intel.com> Link: https://lore.kernel.org/r/20241031202011.1580522-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When calculating the physical address range based on the iotlb and mr
[start,end) ranges, the offset of mr->start relative to map->start
is not taken into account. This leads to some incorrect and duplicate
mappings.
For the case when mr->start < map->start the code is already correct:
the range in [mr->start, map->start) was handled by a different
iteration.
Fixes: 94abbccdf291 ("vdpa/mlx5: Add shared memory registration code") Cc: stable@vger.kernel.org Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com> Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20241021134040.975221-2-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When 'ioctl(OCFS2_IOC_GROUP_ADD, ...)' has failed for the particular
inode in 'ocfs2_verify_group_and_input()', corresponding buffer head
remains cached and subsequent call to the same 'ioctl()' for the same
inode issues the BUG() in 'ocfs2_set_new_buffer_uptodate()' (trying
to cache the same buffer head of that inode). Fix this by uncaching
the buffer head with 'ocfs2_remove_from_cache()' on error path in
'ocfs2_group_add()'.
Link: https://lkml.kernel.org/r/20241114043844.111847-1-dmantipov@yandex.ru Fixes: 7909f2bf8353 ("[PATCH 2/2] ocfs2: Implement group add for online resize") Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Reported-by: syzbot+453873f1588c2d75b447@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=453873f1588c2d75b447 Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Dmitry Antipov <dmantipov@yandex.ru> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mark@fasheh.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We triggered a NULL pointer dereference for ac.preferred_zoneref->zone in
alloc_pages_bulk_noprof() when the task is migrated between cpusets.
When cpuset is enabled, in prepare_alloc_pages(), ac->nodemask may be
¤t->mems_allowed. when first_zones_zonelist() is called to find
preferred_zoneref, the ac->nodemask may be modified concurrently if the
task is migrated between different cpusets. Assuming we have 2 NUMA Node,
when traversing Node1 in ac->zonelist, the nodemask is 2, and when
traversing Node2 in ac->zonelist, the nodemask is 1. As a result, the
ac->preferred_zoneref points to NULL zone.
In alloc_pages_bulk_noprof(), for_each_zone_zonelist_nodemask() finds a
allowable zone and calls zonelist_node_idx(ac.preferred_zoneref), leading
to NULL pointer dereference.
__alloc_pages_noprof() fixes this issue by checking NULL pointer in commit ea57485af8f4 ("mm, page_alloc: fix check for NULL preferred_zone") and
commit df76cee6bbeb ("mm, page_alloc: remove redundant checks from alloc
fastpath").
To fix it, check NULL pointer for preferred_zoneref->zone.
Link: https://lkml.kernel.org/r/20241113083235.166798-1-tujinjiang@huawei.com Fixes: 387ba26fb1cb ("mm/page_alloc: add a bulk page allocator") Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Alexander Lobakin <alobakin@pm.me> Cc: David Hildenbrand <david@redhat.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
are passed to the kexec/kdump kernel. Only the ima_kexec buffer
experienced incorrect decryption. Debugging identified a bug in
early_memremap_is_setup_data(), where an incorrect range calculation
occurred due to the len variable in struct setup_data ended up only
representing the length of the data field, excluding the struct's size,
and thus leading to miscalculation.
Address a similar issue in memremap_is_setup_data() while at it.
The patchset introducing kernel_sec_start/end variables to separate the
kernel/lowmem memory mappings, broke the mapping of the kernel memory
for xipkernels.
kernel_sec_start/end variables are in RO area before the MMU is switched
on for xipkernels.
So these cannot be set early in boot in head.S. Fix this by setting these
after MMU is switched on.
xipkernels need two different mappings for kernel text (starting at
CONFIG_XIP_PHYS_ADDR) and data (starting at CONFIG_PHYS_OFFSET).
Also, move the kernel code mapping from devicemaps_init() to map_kernel().
Fixes: a91da5457085 ("ARM: 9089/1: Define kernel physical section start and end") Signed-off-by: Harith George <harith.g@alifsemi.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
In the pktgen_sample01_simple.sh script, the device variable is uppercase
'DEV' instead of lowercase 'dev'. Because of this typo, the script cannot
enable UDP tx checksum.
In error flow of mlx5_tc_ct_entry_add_rule(), in case ct_rule_add()
callback returns error, zone_rule->attr is used uninitiated. Fix it to
use attr which has the needed pointer value.
The kTLS tx handling code is using a mix of get_page() and
page_ref_inc() APIs to increment the page reference. But on the release
path (mlx5e_ktls_tx_handle_resync_dump_comp()), only put_page() is used.
This is an issue when using pages from large folios: the get_page()
references are stored on the folio page while the page_ref_inc()
references are stored directly in the given page. On release the folio
page will be dereferenced too many times.
This was found while doing kTLS testing with sendfile() + ZC when the
served file was read from NFS on a kernel with NFS large folios support
(commit 49b29a573da8 ("nfs: add support for large folios")).
The referenced commits introduced a two-step process for deleting FTEs:
- Lock the FTE, delete it from hardware, set the hardware deletion function
to NULL and unlock the FTE.
- Lock the parent flow group, delete the software copy of the FTE, and
remove it from the xarray.
However, this approach encounters a race condition if a rule with the same
match value is added simultaneously. In this scenario, fs_core may set the
hardware deletion function to NULL prematurely, causing a panic during
subsequent rule deletions.
To prevent this, ensure the active flag of the FTE is checked under a lock,
which will prevent the fs_core layer from attaching a new steering rule to
an FTE that is in the process of deletion.
The 'state' can't be NULL, we should check crtc_state.
Fix warning:
drivers/gpu/drm/rockchip/rockchip_drm_vop.c:1096
vop_plane_atomic_async_check() warn: variable dereferenced before check
'state' (see line 1077)
Netlink supports iterative dumping of data. It provides the families
the following ops:
- start - (optional) kicks off the dumping process
- dump - actual dump helper, keeps getting called until it returns 0
- done - (optional) pairs with .start, can be used for cleanup
The whole process is asynchronous and the repeated calls to .dump
don't actually happen in a tight loop, but rather are triggered
in response to recvmsg() on the socket.
This gives the user full control over the dump, but also means that
the user can close the socket without getting to the end of the dump.
To make sure .start is always paired with .done we check if there
is an ongoing dump before freeing the socket, and if so call .done.
The complication is that sockets can get freed from BH and .done
is allowed to sleep. So we use a workqueue to defer the call, when
needed.
Unfortunately this does not work correctly. What we defer is not
the cleanup but rather releasing a reference on the socket.
We have no guarantee that we own the last reference, if someone
else holds the socket they may release it in BH and we're back
to square one.
The whole dance, however, appears to be unnecessary. Only the user
can interact with dumps, so we can clean up when socket is closed.
And close always happens in process context. Some async code may
still access the socket after close, queue notification skbs to it etc.
but no dumps can start, end or otherwise make progress.
Delete the workqueue and flush the dump state directly from the release
handler. Note that further cleanup is possible in -next, for instance
we now always call .done before releasing the main module reference,
so dump doesn't have to take a reference of its own.
Reported-by: syzkaller <syzkaller@googlegroups.com> Fixes: ed5d7788a934 ("netlink: Do not schedule work from sk_destruct") Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241106015235.2458807-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The comment before the config of the GPLL3 PLL says that the
PLL should run at 930 MHz. In contrary to this, calculating
the frequency from the current configuration values by using
19.2 MHz as input frequency defined in 'qcs404.dtsi', it gives
921.6 MHz:
Since commit 92a81562e695 ("leds: lp55xx: Add multicolor framework
support to lp55xx") there are two subsequent tests if the chan_nr
(reg property) is in valid range. One in the lp55xx_init_led()
function and one in the lp55xx_parse_common_child() function that
was added with the mentioned commit.
There are two issues with that.
First is in the lp55xx_parse_common_child() function where the reg
property is tested right after it is read from the device tree.
Test for the upper range is not correct though. Valid reg values are
0 to (max_channel - 1) so it should be >=.
Second issue is that in case the parsed value is out of the range
the probe just fails and no error message is shown as the code never
reaches the second test that prints and error message.
Remove the test form lp55xx_parse_common_child() function completely
and keep the one in lp55xx_init_led() function to deal with it.
Fixes: 92a81562e695 ("leds: lp55xx: Add multicolor framework support to lp55xx") Cc: stable@vger.kernel.org Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com> Link: https://lore.kernel.org/r/20241017150812.3563629-1-michal.vokac@ysoft.com Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM_LPAE_LVL_IDX() takes into account concatenated PGDs and can return
an index spanning multiple page-table pages given a sufficiently large
input address. However, when the resulting index is used to calculate
the number of remaining entries in the page, the possibility of
concatenation is ignored and we end up computing a negative upper bound:
On the map path, this results in a negative 'mapped' value being
returned but on the unmap path we can leak child tables if they are
skipped in __arm_lpae_free_pgtable().
Introduce an arm_lpae_max_entries() helper to convert a table index into
the remaining number of entries within a single page-table page.
Since 5.14-rc1, NUMA events will only be folded from per-CPU statistics to
per zone and global statistics when the user actually needs it.
Currently, the kernel has performs the fold operation when reading
/proc/vmstat, but does not perform the fold operation in /proc/zoneinfo.
This can lead to inaccuracies in the following statistics in zoneinfo:
- numa_hit
- numa_miss
- numa_foreign
- numa_interleave
- numa_local
- numa_other
Therefore, before printing per-zone vm_numa_event when reading
/proc/zoneinfo, we should also perform the fold operation.
Link: https://lkml.kernel.org/r/1730433998-10461-1-git-send-email-mengensun@tencent.com Fixes: f19298b9516c ("mm/vmstat: convert NUMA statistics to basic NUMA counters") Signed-off-by: MengEn Sun <mengensun@tencent.com> Reviewed-by: JinLiang Zheng <alexjlzheng@tencent.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current mod command causes a null pointer dereference. While commit 0f17976568b3f ("ftrace: Fix regression with module command in stack_trace_filter")
has addressed part of the issue, it left a corner case unhandled, which still
results in a kernel crash.
Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/20241120052750.275463-1-guoweikang.kernel@gmail.com Fixes: 04ec7bb642b77 ("tracing: Have the trace_array hold the list of registered func probes"); Signed-off-by: guoweikang <guoweikang.kernel@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a check to the ovl_dentry_weird() function to prevent the
processing of directory inodes that lack the lookup function.
This is important because such inodes can cause errors in overlayfs
when passed to the lowerstack.
Per UVC 1.1+ specification 3.7.2, units and terminals must have a non-zero
unique ID.
```
Each Unit and Terminal within the video function is assigned a unique
identification number, the Unit ID (UID) or Terminal ID (TID), contained in
the bUnitID or bTerminalID field of the descriptor. The value 0x00 is
reserved for undefined ID,
```
So, deny allocating an entity with ID 0 or an ID that belongs to a unit
that is already added to the list of entities.
This also prevents some syzkaller reproducers from triggering warnings due
to a chain of entities referring to themselves. In one particular case, an
Output Unit is connected to an Input Unit, both with the same ID of 1. But
when looking up for the source ID of the Output Unit, that same entity is
found instead of the input entity, which leads to such warnings.
In another case, a backward chain was considered finished as the source ID
was 0. Later on, that entity was found, but its pads were not valid.
Here is a sample stack trace for one of those cases.
uvc_unregister_video() can be called asynchronously from
uvc_disconnect(). If the device is still streaming when that happens, a
plethora of race conditions can occur.
Make sure that the device has stopped streaming before exiting this
function.
If the user still holds handles to the driver's file descriptors, any
ioctl will return -ENODEV from the v4l2 core.
This change makes uvc more consistent with the rest of the v4l2 drivers
using the vb2_fop_* and vb2_ioctl_* helpers.
This driver (and many other usb drivers) always had this problem, but it
wasn't possible to easily fix this until the vb2_video_unregister_device()
helper was added. So the Fixes tag points to the creation of that helper.
projects / thirdparty / kernel / stable.git / log
