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Linux kernel
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Pull i2c fixes from Wolfram Sang:
- hisi: update maintainership
- fix several issues in rtl9300 xfer:
- check message length boundaries
- correct multi-byte value composition on write
- increase polling timeout
- fix block transfer protocol
* tag 'i2c-for-6.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: rtl9300: Add missing count byte for SMBus Block Ops
i2c: rtl9300: Increase timeout for transfer polling
i2c: rtl9300: Fix multi-byte I2C write
i2c: rtl9300: Fix out-of-bounds bug in rtl9300_i2c_smbus_xfer
MAINTAINERS: i2c: Update i2c_hisi entry
Pull perf fix from Borislav Petkov:
- Fix a case where the events throttling logic operates on inactive
events
* tag 'perf_urgent_for_v6.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Avoid undefined behavior from stopping/starting inactive events
i2c-host-fixes for v6.17-rc3
- hisi: update maintainership
- rtl9300: fix several issues in xfer
- check message length boundaries
- correct multi-byte value composition on write
- increase polling timeout
- fix block transfer protocol
Pull x86 fixes from Borislav Petkov:
- Fix the GDS mitigation detection on some machines after the recent
attack vectors conversion
- Filter out the invalid machine reset reason value -1 when running as
a guest as in such cases the reason why the machine was rebooted does
not make a whole lot of sense
- Init the resource control machinery on Hygon hw in order to avoid a
division by zero and to actually enable the feature on hw which
supports it
* tag 'x86_urgent_for_v6.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bugs: Fix GDS mitigation selecting when mitigation is off
x86/CPU/AMD: Ignore invalid reset reason value
x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper
Calling pmu->start()/stop() on perf events in PERF_EVENT_STATE_OFF can
leave event->hw.idx at -1. When PMU drivers later attempt to use this
negative index as a shift exponent in bitwise operations, it leads to UBSAN
shift-out-of-bounds reports.
The issue is a logical flaw in how event groups handle throttling when some
members are intentionally disabled. Based on the analysis and the
reproducer provided by Mark Rutland (this issue on both arm64 and x86-64).
The scenario unfolds as follows:
1. A group leader event is configured with a very aggressive sampling
period (e.g., sample_period = 1). This causes frequent interrupts and
triggers the throttling mechanism.
2. A child event in the same group is created in a disabled state
(.disabled = 1). This event remains in PERF_EVENT_STATE_OFF.
Since it hasn't been scheduled onto the PMU, its event->hw.idx remains
initialized at -1.
3. When throttling occurs, perf_event_throttle_group() and later
perf_event_unthrottle_group() iterate through all siblings, including
the disabled child event.
4. perf_event_throttle()/unthrottle() are called on this inactive child
event, which then call event->pmu->start()/stop().
5. The PMU driver receives the event with hw.idx == -1 and attempts to
use it as a shift exponent. e.g., in macros like PMCNTENSET(idx),
leading to the UBSAN report.
The throttling mechanism attempts to start/stop events that are not
actively scheduled on the hardware.
Move the state check into perf_event_throttle()/perf_event_unthrottle() so
that inactive events are skipped entirely. This ensures only active events
with a valid hw.idx are processed, preventing undefined behavior and
silencing UBSAN warnings. The corrected check ensures true before
proceeding with PMU operations.
The problem can be reproduced with the syzkaller reproducer:
Fixes: 9734e25fbf5a ("perf: Fix the throttle logic for a group")
Signed-off-by: Yunseong Kim <ysk@kzalloc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20250812181046.292382-2-ysk@kzalloc.com
The expected on-wire format of an SMBus Block Write is
S Addr Wr [A] Comm [A] Count [A] Data [A] Data [A] ... [A] Data [A] P
Everything starting from the Count byte is provided by the I2C subsystem in
the array data->block. But the driver was skipping the Count byte
(data->block[0]) when sending it to the RTL93xx I2C controller.
Only the actual data could be seen on the wire:
S Addr Wr [A] Comm [A] Data [A] Data [A] ... [A] Data [A] P
This wire format is not SMBus Block Write compatible but matches the format
of an I2C Block Write. Simply adding the count byte to the buffer for the
I2C controller is enough to fix the transmission.
This also affects read because the I2C controller must receive the count
byte + $count * data bytes.
Fixes: c366be720235 ("i2c: Add driver for the RTL9300 I2C controller")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Cc: <stable@vger.kernel.org> # v6.13+
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250810-i2c-rtl9300-multi-byte-v5-4-cd9dca0db722@narfation.org
Pull MIPS fixes from Thomas Bogendoerfer:
"Fix ethernet on Lantiq boards"
* tag 'mips-fixes_6.17_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
mips: lantiq: xway: sysctrl: rename the etop node
mips: dts: lantiq: danube: add missing burst length property
The current GDS mitigation logic incorrectly returns early when the
attack vector mitigation is turned off, which leads to two problems:
1. CPUs without ARCH_CAP_GDS_CTRL support are incorrectly marked with
GDS_MITIGATION_OFF when they should be marked as
GDS_MITIGATION_UCODE_NEEDED.
2. The mitigation state checks and locking verification that follow are
skipped, which means:
- fail to detect if the mitigation was locked
- miss the warning when trying to disable a locked mitigation
Remove the early return to ensure proper mitigation state handling. This
allows:
- Proper mitigation classification for non-ARCH_CAP_GDS_CTRL CPUs
- Complete mitigation state verification
This also addresses the failed MSR 0x123 write attempt at boot on
non-ARCH_CAP_GDS_CTRL CPUs:
unchecked MSR access error: WRMSR to 0x123 (tried to write 0x0000000000000010) at rIP: ... (update_gds_msr)
Call Trace:
identify_secondary_cpu
start_secondary
common_startup_64
WARNING: CPU: 1 PID: 0 at arch/x86/kernel/cpu/bugs.c:1053 update_gds_msr
[ bp: Massage, zap superfluous braces. ]
Fixes: 8c7261abcb7ad ("x86/bugs: Add attack vector controls for GDS")
Suggested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Link: https://lore.kernel.org/20250819023356.2012-1-lirongqing@baidu.com
Pull x86 fixes from Borislav Petkov:
- Remove a transitional asm/cpuid.h header which was added only as a
fallback during cpuid helpers reorg
- Initialize reserved fields in the SVSM page validation calls
structure to zero in order to allow for future structure extensions
- Have the sev-guest driver's buffers used in encryption operations be
in linear mapping space as the encryption operation can be offloaded
to an accelerator
- Have a read-only MSR write when in an AMD SNP guest trap to the
hypervisor as it is usually done. This makes the guest user
experience better by simply raising a #GP instead of terminating said
guest
- Do not output AVX512 elapsed time for kernel threads because the data
is wrong and fix a NULL pointer dereferencing in the process
- Adjust the SRSO mitigation selection to the new attack vectors
* tag 'x86_urgent_for_v6.17_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpuid: Remove transitional <asm/cpuid.h> header
x86/sev: Ensure SVSM reserved fields in a page validation entry are initialized to zero
virt: sev-guest: Satisfy linear mapping requirement in get_derived_key()
x86/sev: Improve handling of writes to intercepted TSC MSRs
x86/fpu: Fix NULL dereference in avx512_status()
x86/bugs: Select best SRSO mitigation
The timeout for transfers was only set to 2ms. Because of this relatively
low limit, 12-byte read operations to the frontend MCU of a RTL8239 POE PSE
chip cluster was consistently resulting in a timeout.
The original OpenWrt downstream driver [1] was not using any timeout limit
at all. This is also possible by setting the timeout_us parameter of
regmap_read_poll_timeout() to 0. But since the driver currently implements
the ETIMEDOUT error, it is more sensible to increase the timeout in such a
way that communication with the (quite common) Realtek I2C-connected POE
management solution is possible.
[1] https://git.openwrt.org/?p=openwrt/openwrt.git;a=blob;f=target/linux/realtek/files-6.12/drivers/i2c/busses/i2c-rtl9300.c;h=c4d973195ef39dc56d6207e665d279745525fcac#l202
Fixes: c366be720235 ("i2c: Add driver for the RTL9300 I2C controller")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Cc: <stable@vger.kernel.org> # v6.13+
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250810-i2c-rtl9300-multi-byte-v5-3-cd9dca0db722@narfation.org
Pull modules fix from Daniel Gomez:
"This includes a fix part of the KSPP (Kernel Self Protection Project)
to replace the deprecated and unsafe strcpy() calls in the kernel
parameter string handler and sysfs parameters for built-in modules.
Single commit, no functional changes"
* tag 'modules-6.17-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux:
params: Replace deprecated strcpy() with strscpy() and memcpy()
Bindig requires a node name matching ‘^ethernet@[0-9a-f]+$’. This patch
changes the clock name from “etop” to “ethernet”.
This fixes the following warning:
arch/mips/boot/dts/lantiq/danube_easy50712.dtb: etop@e180000 (lantiq,etop-xway): $nodename:0: 'etop@e180000' does not match '^ethernet@[0-9a-f]+$'
from schema $id: http://devicetree.org/schemas/net/lantiq,etop-xway.yaml#
Fixes: dac0bad93741 ("dt-bindings: net: lantiq,etop-xway: Document Lantiq Xway ETOP bindings")
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Acked-by: Jakub Kicinski <kuba@kernel.org>
The reset reason value may be "all bits set", e.g. 0xFFFFFFFF. This is a
commonly used error response from hardware. This may occur due to a real
hardware issue or when running in a VM.
The user will see all reset reasons reported in this case.
Check for an error response value and return early to avoid decoding
invalid data.
Also, adjust the data variable type to match the hardware register size.
Fixes: ab8131028710 ("x86/CPU/AMD: Print the reason for the last reset")
Reported-by: Libing He <libhe@redhat.com>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250721181155.3536023-1-yazen.ghannam@amd.com
Pull turbostat updates from Len Brown:
"tools/power turbostat: version 2025.09.09
- Probe and display L3 Cache topology
- Add ability to average an added counter (useful for pre-integrated
"counters", such as Watts)
- Break the limit of 64 built-in counters
- Assorted bug fixes and minor feature tweaks"
* tag 'turbostat-2025.09.09' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: version 2025.09.09
tools/power turbostat: Handle non-root legacy-uncore sysfs permissions
tools/power turbostat: standardize PER_THREAD_PARAMS
tools/power turbostat: Fix DMR support
tools/power turbostat: add format "average" for external attributes
tools/power turbostat: delete GET_PKG()
tools/power turbostat: probe and display L3 cache topology
tools/power turbostat: Support more than 64 built-in-counters
tools/power turbostat.8: Document Totl%C0, Any%C0, GFX%C0, CPUGFX% columns
tools/power turbostat: Fix bogus SysWatt for forked program
tools/power turbostat: Handle cap_get_proc() ENOSYS
tools/power turbostat: Fix build with musl
tools/power turbostat: verify arguments to params --show and --hide
tools/power turbostat: regression fix: --show C1E%
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