Linux kernel
============
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several of them using the Restructured Text markup notation.
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requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
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Pull cxl fixes from Dan Williams:
"Several fixes for CXL region creation crashes, leaks and failures.
This is mainly fallout from the original implementation of dynamic CXL
region creation (instantiate new physical memory pools) that arrived
in v6.0-rc1.
Given the theme of "failures in the presence of pass-through decoders"
this also includes new regression test infrastructure for that case.
Summary:
- Fix region creation crash with pass-through decoders
- Fix region creation crash when no decoder allocation fails
- Fix region creation crash when scanning regions to enforce the
increasing physical address order constraint that CXL mandates
- Fix a memory leak for cxl_pmem_region objects, track 1:N instead of
1:1 memory-device-to-region associations.
- Fix a memory leak for cxl_region objects when regions with active
targets are deleted
- Fix assignment of NUMA nodes to CXL regions by CFMWS (CXL Window)
emulated proximity domains.
- Fix region creation failure for switch attached devices downstream
of a single-port host-bridge
- Fix false positive memory leak of cxl_region objects by recycling
recently used region ids rather than freeing them
- Add regression test infrastructure for a pass-through decoder
configuration
- Fix some mailbox payload handling corner cases"
* tag 'cxl-fixes-for-6.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/region: Recycle region ids
cxl/region: Fix 'distance' calculation with passthrough ports
tools/testing/cxl: Add a single-port host-bridge regression config
tools/testing/cxl: Fix some error exits
cxl/pmem: Fix cxl_pmem_region and cxl_memdev leak
cxl/region: Fix cxl_region leak, cleanup targets at region delete
cxl/region: Fix region HPA ordering validation
cxl/pmem: Use size_add() against integer overflow
cxl/region: Fix decoder allocation crash
ACPI: NUMA: Add CXL CFMWS 'nodes' to the possible nodes set
cxl/pmem: Fix failure to account for 8 byte header for writes to the device LSA.
cxl/region: Fix null pointer dereference due to pass through decoder commit
cxl/mbox: Add a check on input payload size
Pull hwmon fixes from Guenter Roeck:
"Fix two regressions:
- Commit 54cc3dbfc10d ("hwmon: (pmbus) Add regulator supply into
macro") resulted in regulator undercount when disabling regulators.
Revert it.
- The thermal subsystem rework caused the scmi driver to no longer
register with the thermal subsystem because index values no longer
match. To fix the problem, the scmi driver now directly registers
with the thermal subsystem, no longer through the hwmon core"
* tag 'hwmon-for-v6.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
Revert "hwmon: (pmbus) Add regulator supply into macro"
hwmon: (scmi) Register explicitly with Thermal Framework
At region creation time the next region-id is atomically cached so that
there is predictability of region device names. If that region is
destroyed and then a new one is created the region id increments. That
ends up looking like a memory leak, or is otherwise surprising that
identifiers roll forward even after destroying all previously created
regions.
Try to reuse rather than free old region ids at region release time.
While this fixes a cosmetic issue, the needlessly advancing memory
region-id gives the appearance of a memory leak, hence the "Fixes" tag,
but no "Cc: stable" tag.
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Fixes: 779dd20cfb56 ("cxl/region: Add region creation support")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/166752186062.947915.13200195701224993317.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull perf fixes from Borislav Petkov:
- Add Cooper Lake's stepping to the PEBS guest/host events isolation
fixed microcode revisions checking quirk
- Update Icelake and Sapphire Rapids events constraints
- Use the standard energy unit for Sapphire Rapids in RAPL
- Fix the hw_breakpoint test to fail more graciously on !SMP configs
* tag 'perf_urgent_for_v6.1_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Add Cooper Lake stepping to isolation_ucodes[]
perf/x86/intel: Fix pebs event constraints for SPR
perf/x86/intel: Fix pebs event constraints for ICL
perf/x86/rapl: Use standard Energy Unit for SPR Dram RAPL domain
perf/hw_breakpoint: test: Skip the test if dependencies unmet
This reverts commit 54cc3dbfc10dc3db7cb1cf49aee4477a8398fbde.
Zev Weiss reports that the reverted patch may cause a regulator
undercount. Here is his report:
... having regulator-dummy set as a supply on my PMBus regulators
(instead of having them as their own top-level regulators without
an upstream supply) leads to enable-count underflow errors when
disabling them:
# echo 0 > /sys/bus/platform/devices/efuse01/state
[ 906.094477] regulator-dummy: Underflow of regulator enable count
[ 906.100563] Failed to disable vout: -EINVAL
[ 136.992676] reg-userspace-consumer efuse01: Failed to configure state: -22
Zev reports that reverting the patch fixes the problem. So let's do that
for now.
Fixes: 54cc3dbfc10d ("hwmon: (pmbus) Add regulator supply into macro")
Cc: Marcello Sylvester Bauer <sylv@sylv.io>
Reported-by: Zev Weiss <zev@bewilderbeest.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
When programming port decode targets, the algorithm wants to ensure that
two devices are compatible to be programmed as peers beneath a given
port. A compatible peer is a target that shares the same dport, and
where that target's interleave position also routes it to the same
dport. Compatibility is determined by the device's interleave position
being >= to distance. For example, if a given dport can only map every
Nth position then positions less than N away from the last target
programmed are incompatible.
The @distance for the host-bridge's cxl_port in a simple dual-ported
host-bridge configuration with 2 direct-attached devices is 1, i.e. An
x2 region divided by 2 dports to reach 2 region targets.
An x4 region under an x2 host-bridge would need 2 intervening switches
where the @distance at the host bridge level is 2 (x4 region divided by
2 switches to reach 4 devices).
However, the distance between peers underneath a single ported
host-bridge is always zero because there is no limit to the number of
devices that can be mapped. In other words, there are no decoders to
program in a passthrough, all descendants are mapped and distance only
starts matters for the intervening descendant ports of the passthrough
port.
Add tracking for the number of dports mapped to a port, and use that to
detect the passthrough case for calculating @distance.
Cc: <stable@vger.kernel.org>
Reported-by: Bobo WL <lmw.bobo@gmail.com>
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: http://lore.kernel.org/r/20221010172057.00001559@huawei.com
Fixes: 27b3f8d13830 ("cxl/region: Program target lists")
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/166752185440.947915.6617495912508299445.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull x86 fixes from Borislav Petkov:
- Add new Intel CPU models
- Enforce that TDX guests are successfully loaded only on TDX hardware
where virtualization exception (#VE) delivery on kernel memory is
disabled because handling those in all possible cases is "essentially
impossible"
- Add the proper include to the syscall wrappers so that BTF can see
the real pt_regs definition and not only the forward declaration
* tag 'x86_urgent_for_v6.1_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add several Intel server CPU model numbers
x86/tdx: Panic on bad configs that #VE on "private" memory access
x86/tdx: Prepare for using "INFO" call for a second purpose
x86/syscall: Include asm/ptrace.h in syscall_wrapper header
The intel_pebs_isolation quirk checks both model number and stepping.
Cooper Lake has a different stepping (11) than the other Skylake Xeon.
It cannot benefit from the optimization in commit 9b545c04abd4f
("perf/x86/kvm: Avoid unnecessary work in guest filtering").
Add the stepping of Cooper Lake into the isolation_ucodes[] table.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221031154550.571663-1-kan.liang@linux.intel.com
Available sensors are enumerated and reported by the SCMI platform server
using a 16bit identification number; not all such sensors are of a type
supported by hwmon subsystem and, among the supported ones, only a subset
could be temperature sensors that have to be registered with the Thermal
Framework.
Potential clashes between hwmon channels indexes and the underlying real
sensors IDs do not play well with the hwmon<-->thermal bridge automatic
registration routines and could need a sensible number of fake dummy
sensors to be made up in order to keep indexes and IDs in sync.
Avoid to use the hwmon<-->thermal bridge dropping the HWMON_C_REGISTER_TZ
attribute and instead explicit register temperature sensors directly with
the Thermal Framework.
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-hwmon@vger.kernel.org
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20221031114018.59048-1-cristian.marussi@arm.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Jonathan reports that region creation fails when a single-port
host-bridge connects to a multi-port switch. Mock up that configuration
so a fix can be tested and regression tested going forward.
Reported-by: Bobo WL <lmw.bobo@gmail.com>
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: http://lore.kernel.org/r/20221010172057.00001559@huawei.com
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/166752184838.947915.2167957540894293891.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull Kbuild fixes from Masahiro Yamada:
- Use POSIX-compatible grep options
- Document git-related tips for reproducible builds
- Fix a typo in the modpost rule
- Suppress SIGPIPE error message from gcc-ar and llvm-ar
- Fix segmentation fault in the menuconfig search
* tag 'kbuild-fixes-v6.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: fix segmentation fault in menuconfig search
kbuild: fix SIGPIPE error message for AR=gcc-ar and AR=llvm-ar
kbuild: fix typo in modpost
Documentation: kbuild: Add description of git for reproducible builds
kbuild: use POSIX-compatible grep option
These servers are all on the public versions of the roadmap. The model
numbers for Grand Ridge, Granite Rapids, and Sierra Forest were included
in the September 2022 edition of the Instruction Set Extensions document.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20221103203310.5058-1-tony.luck@intel.com
According to the latest event list, update the MEM_INST_RETIRED events
which support the DataLA facility for SPR.
Fixes: 61b985e3e775 ("perf/x86/intel: Add perf core PMU support for Sapphire Rapids")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221031154119.571386-2-kan.liang@linux.intel.com
Fix a few typos where 'goto err_port' was used rather than the object
specific cleanup.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/166752184255.947915.16163477849330181425.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>