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Linux kernel
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Pull perf fixes from Borislav Petkov:
- Fix "same task" check when redirecting event output
- Do not wait unconditionally for RCU on the event migration path if
there are no events to migrate
* tag 'perf_urgent_for_v6.3_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix the same task check in perf_event_set_output
perf: Optimize perf_pmu_migrate_context()
Pull x86 fixes from Borislav Petkov:
- Add a new Intel Arrow Lake CPU model number
- Fix a confusion about how to check the version of the ACPI spec which
supports a "online capable" bit in the MADT table which lead to a
bunch of boot breakages with Zen1 systems and VMs
* tag 'x86_urgent_for_v6.3_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add model number for Intel Arrow Lake processor
x86/acpi/boot: Correct acpi_is_processor_usable() check
x86/ACPI/boot: Use FADT version to check support for online capable
The same task check in perf_event_set_output has some potential issues
for some usages.
For the current perf code, there is a problem if using of
perf_event_open() to have multiple samples getting into the same mmap’d
memory when they are both attached to the same process.
https://lore.kernel.org/all/92645262-D319-4068-9C44-2409EF44888E@gmail.com/
Because the event->ctx is not ready when the perf_event_set_output() is
invoked in the perf_event_open().
Besides the above issue, before the commit bd2756811766 ("perf: Rewrite
core context handling"), perf record can errors out when sampling with
a hardware event and a software event as below.
$ perf record -e cycles,dummy --per-thread ls
failed to mmap with 22 (Invalid argument)
That's because that prior to the commit a hardware event and a software
event are from different task context.
The problem should be a long time issue since commit c3f00c70276d
("perk: Separate find_get_context() from event initialization").
The task struct is stored in the event->hw.target for each per-thread
event. It is a more reliable way to determine whether two events are
attached to the same task.
The event->hw.target was also introduced several years ago by the
commit 50f16a8bf9d7 ("perf: Remove type specific target pointers"). It
can not only be used to fix the issue with the current code, but also
back port to fix the issues with an older kernel.
Note: The event->hw.target was introduced later than commit
c3f00c70276d. The patch may cannot be applied between the commit
c3f00c70276d and commit 50f16a8bf9d7. Anybody that wants to back-port
this at that period may have to find other solutions.
Fixes: c3f00c70276d ("perf: Separate find_get_context() from event initialization")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Link: https://lkml.kernel.org/r/20230322202449.512091-1-kan.liang@linux.intel.com
Pull compute express link (cxl) fixes from Dan Williams:
"Several fixes for driver startup regressions that landed during the
merge window as well as some older bugs.
The regressions were due to a lack of testing with what the CXL
specification calls Restricted CXL Host (RCH) topologies compared to
the testing with Virtual Host (VH) CXL topologies. A VH topology is
typical PCIe while RCH topologies map CXL endpoints as Root Complex
Integrated endpoints. The impact is some driver crashes on startup.
This merge window also added compatibility for range registers (the
mechanism that CXL 1.1 defined for mapping memory) to treat them like
HDM decoders (the mechanism that CXL 2.0 defined for mapping
Host-managed Device Memory). That work collided with the new region
enumeration code that was tested with CXL 2.0 setups, and fails with
crashes at startup.
Lastly, the DOE (Data Object Exchange) implementation for retrieving
an ACPI-like data table from CXL devices is being reworked for v6.4.
Several fixes fell out of that work that are suitable for v6.3.
All of this has been in linux-next for a while, and all reported
issues [1] have been addressed.
Summary:
- Fix several issues with region enumeration in RCH topologies that
can trigger crashes on driver startup or shutdown.
- Fix CXL DVSEC range register compatibility versus region
enumeration that leads to startup crashes
- Fix CDAT endiannes handling
- Fix multiple buffer handling boundary conditions
- Fix Data Object Exchange (DOE) workqueue usage vs
CONFIG_DEBUG_OBJECTS warn splats"
Link: http://lore.kernel.org/r/20230405075704.33de8121@canb.auug.org.au [1]
* tag 'cxl-fixes-6.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/hdm: Extend DVSEC range register emulation for region enumeration
cxl/hdm: Limit emulation to the number of range registers
cxl/region: Move coherence tracking into cxl_region_attach()
cxl/region: Fix region setup/teardown for RCDs
cxl/port: Fix find_cxl_root() for RCDs and simplify it
cxl/hdm: Skip emulation when driver manages mem_enable
cxl/hdm: Fix double allocation of @cxlhdm
PCI/DOE: Fix memory leak with CONFIG_DEBUG_OBJECTS=y
PCI/DOE: Silence WARN splat with CONFIG_DEBUG_OBJECTS=y
cxl/pci: Handle excessive CDAT length
cxl/pci: Handle truncated CDAT entries
cxl/pci: Handle truncated CDAT header
cxl/pci: Fix CDAT retrieval on big endian
Successor to Lunar Lake.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230404174641.426593-1-tony.luck@intel.com
Thomas reported that offlining CPUs spends a lot of time in
synchronize_rcu() as called from perf_pmu_migrate_context() even though
he's not actually using uncore events.
Turns out, the thing is unconditionally waiting for RCU, even if there's
no actual events to migrate.
Fixes: 0cda4c023132 ("perf: Introduce perf_pmu_migrate_context()")
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lkml.kernel.org/r/20230403090858.GT4253@hirez.programming.kicks-ass.net
Pull cifs client fixes from Steve French:
"Two cifs/smb3 client fixes, one for stable:
- double lock fix for a cifs/smb1 reconnect path
- DFS prefixpath fix for reconnect when server moved"
* tag '6.3-rc5-smb3-cifs-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: double lock in cifs_reconnect_tcon()
cifs: sanitize paths in cifs_update_super_prepath.
Pick up the fixes (first 6 patches) from the DOE rework series from
Lukas for v6.3-rc.
Link: https://lore.kernel.org/all/cover.1678543498.git.lukas@wunner.de/
The logic in acpi_is_processor_usable() requires the online capable
bit be set for hotpluggable CPUs. The online capable bit has been
introduced in ACPI 6.3.
However, for ACPI revisions < 6.3 which do not support that bit, CPUs
should be reported as usable, not the other way around.
Reverse the check.
[ bp: Rewrite commit message. ]
Fixes: e2869bd7af60 ("x86/acpi/boot: Do not register processors that cannot be onlined for x2APIC")
Suggested-by: Miguel Luis <miguel.luis@oracle.com>
Suggested-by: Boris Ostrovsky <boris.ovstrosky@oracle.com>
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: David R <david@unsolicited.net>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230327191026.3454-2-eric.devolder@oracle.com
Pull char/misc driver fixes from Greg KH:
"Here are a small set of various small driver changes for 6.3-rc6.
Included in here are:
- iio driver fixes for reported problems
- coresight hwtracing bugfix for reported problem
- small counter driver bugfixes
All have been in linux-next for a while with no reported problems"
* tag 'char-misc-6.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
coresight: etm4x: Do not access TRCIDR1 for identification
coresight-etm4: Fix for() loop drvdata->nr_addr_cmp range bug
iio: adc: ti-ads7950: Set `can_sleep` flag for GPIO chip
iio: adc: palmas_gpadc: fix NULL dereference on rmmod
counter: 104-quad-8: Fix Synapse action reported for Index signals
counter: 104-quad-8: Fix race condition between FLAG and CNTR reads
iio: adc: max11410: fix read_poll_timeout() usage
iio: dac: cio-dac: Fix max DAC write value check for 12-bit
iio: light: cm32181: Unregister second I2C client if present
iio: accel: kionix-kx022a: Get the timestamp from the driver's private data in the trigger_handler
iio: adc: ad7791: fix IRQ flags
iio: buffer: make sure O_NONBLOCK is respected
iio: buffer: correctly return bytes written in output buffers
iio: light: vcnl4000: Fix WARN_ON on uninitialized lock
iio: adis16480: select CONFIG_CRC32
drivers: iio: adc: ltc2497: fix LSB shift
iio: adc: qcom-spmi-adc5: Fix the channel name
This lock was supposed to be an unlock.
Fixes: 6cc041e90c17 ("cifs: avoid races in parallel reconnects in smb1")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
One motivation for mapping range registers to decoder objects is
to use those settings for region autodiscovery.
The need to map a region for devices programmed to use range registers
is especially urgent now that the kernel no longer routes "Soft
Reserved" ranges in the memory map to device-dax by default. The CXL
memory range loses all access mechanisms.
Complete the implementation by marking the DPA reservation and setting
the endpoint-decoder state to signal autodiscovery. Note that the
default settings of ways=1 and granularity=4096 set in cxl_decode_init()
do not need to be updated.
Fixes: 09d09e04d2fc ("cxl/dax: Create dax devices for CXL RAM regions")
Tested-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Gregory Price <gregory.price@memverge.com>
Link: https://lore.kernel.org/r/168012575521.221280.14177293493678527326.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
After a pci_doe_task completes, its work_struct needs to be destroyed
to avoid a memory leak with CONFIG_DEBUG_OBJECTS=y.
Fixes: 9d24322e887b ("PCI/DOE: Add DOE mailbox support functions")
Tested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: stable@vger.kernel.org # v6.0+
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/775768b4912531c3b887d405fc51a50e465e1bf9.1678543498.git.lukas@wunner.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
ACPI 6.3 introduced the online capable bit, and also introduced MADT
version 5.
Latter was used to distinguish whether the offset storing online capable
could be used. However ACPI 6.2b has MADT version "45" which is for
an errata version of the ACPI 6.2 spec. This means that the Linux code
for detecting availability of MADT will mistakenly flag ACPI 6.2b as
supporting online capable which is inaccurate as it's an ACPI 6.3 feature.
Instead use the FADT major and minor revision fields to distinguish this.
[ bp: Massage. ]
Fixes: aa06e20f1be6 ("x86/ACPI: Don't add CPUs that are not online capable")
Reported-by: Eric DeVolder <eric.devolder@oracle.com>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/943d2445-84df-d939-f578-5d8240d342cc@unsolicited.net
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