commit b583ef82b6 upstream.
Max Makarov reported kernel panic [1] in perf user callchain code.
The reason for that is the race between uprobe_free_utask and bpf
profiler code doing the perf user stack unwind and is triggered
within uprobe_free_utask function:
- after current->utask is freed and
- before current->utask is set to NULL
general protection fault, probably for non-canonical address 0x9e759c37ee555c76: 0000 [#1] SMP PTI
RIP: 0010:is_uprobe_at_func_entry+0x28/0x80
...
? die_addr+0x36/0x90
? exc_general_protection+0x217/0x420
? asm_exc_general_protection+0x26/0x30
? is_uprobe_at_func_entry+0x28/0x80
perf_callchain_user+0x20a/0x360
get_perf_callchain+0x147/0x1d0
bpf_get_stackid+0x60/0x90
bpf_prog_9aac297fb833e2f5_do_perf_event+0x434/0x53b
? __smp_call_single_queue+0xad/0x120
bpf_overflow_handler+0x75/0x110
...
asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__kmem_cache_free+0x1cb/0x350
...
? uprobe_free_utask+0x62/0x80
? acct_collect+0x4c/0x220
uprobe_free_utask+0x62/0x80
mm_release+0x12/0xb0
do_exit+0x26b/0xaa0
__x64_sys_exit+0x1b/0x20
do_syscall_64+0x5a/0x80
It can be easily reproduced by running following commands in
separate terminals:
# while :; do bpftrace -e 'uprobe:/bin/ls:_start { printf("hit\n"); }' -c ls; done
# bpftrace -e 'profile:hz:100000 { @[ustack()] = count(); }'
Fixing this by making sure current->utask pointer is set to NULL
before we start to release the utask object.
[1] https://github.com/grafana/pyroscope/issues/3673
Fixes: cfa7f3d2c5 ("perf,x86: avoid missing caller address in stack traces captured in uprobe")
Reported-by: Max Makarov <maxpain@linux.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20250109141440.2692173-1-jolsa@kernel.org
[Christian Simon: Rebased for 6.12.y, due to mainline change https://lore.kernel.org/all/20240929144239.GA9475@redhat.com/]
Signed-off-by: Christian Simon <simon@swine.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 87ecfdbc69 upstream.
If find_linux_pte fails, IRQs will not be restored. This is unlikely
to happen in practice since it would have been reported as hanging
hosts, but it should of course be fixed anyway.
Cc: stable@vger.kernel.org
Reported-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b160dc46dd upstream.
This list started as a "when to prefer `expect`" list, but at some point
during writing I changed it to a "prefer `expect` unless..." one. However,
the first bullet remained, which does not make sense anymore.
Thus remove it. In addition, fix nearby typo.
Fixes: 04866494e9 ("Documentation: rust: discuss `#[expect(...)]` in the guidelines")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20241117133127.473937-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit afb41b08c4 upstream.
In H2CTermReq, a FES with value 0x05 means "R2T Limit Exceeded"; but
in C2HTermReq the same value has a different meaning (Data Transfer Limit
Exceeded).
Fixes: 84e009042d ("nvme-tcp: add basic support for the C2HTermReq PDU")
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d0bbe33266 upstream.
The alternative path leads to a build error after a recent change:
sound/pci/hda/patch_realtek.c: In function 'alc233_fixup_lenovo_low_en_micmute_led':
include/linux/stddef.h:9:14: error: called object is not a function or function pointer
9 | #define NULL ((void *)0)
| ^
sound/pci/hda/patch_realtek.c:5041:49: note: in expansion of macro 'NULL'
5041 | #define alc233_fixup_lenovo_line2_mic_hotkey NULL
| ^~~~
sound/pci/hda/patch_realtek.c:5063:9: note: in expansion of macro 'alc233_fixup_lenovo_line2_mic_hotkey'
5063 | alc233_fixup_lenovo_line2_mic_hotkey(codec, fix, action);
Using IS_REACHABLE() is somewhat questionable here anyway since it
leads to the input code not working when the HDA driver is builtin
but input is in a loadable module. Replace this with a hard compile-time
dependency on CONFIG_INPUT. In practice this won't chance much
other than solve the compiler error because it is rare to require
sound output but no input support.
Fixes: f603b15923 ("ALSA: hda/realtek - add supported Mic Mute LED for Lenovo platform")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20250304142620.582191-1-arnd@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 02e9a22cee ]
The headercheck tries to call clang with a mix of compiler arguments
that don't include the target architecture. When building e.g. x86
headers on arm64, this produces a warning like
clang: warning: unknown platform, assuming -mfloat-abi=soft
Add in the KBUILD_CPPFLAGS, which contain the target, in order to make it
build properly.
See also 1b71c2fb04 ("kbuild: userprogs: fix bitsize and target
detection on clang").
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Fixes: feb843a469 ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 49c87f7677 upstream.
arm64 supports multiple huge_pte sizes. Some of the sizes are covered by
a single pte entry at a particular level (PMD_SIZE, PUD_SIZE), and some
are covered by multiple ptes at a particular level (CONT_PTE_SIZE,
CONT_PMD_SIZE). So the function has to figure out the size from the
huge_pte pointer. This was previously done by walking the pgtable to
determine the level and by using the PTE_CONT bit to determine the
number of ptes at the level.
But the PTE_CONT bit is only valid when the pte is present. For
non-present pte values (e.g. markers, migration entries), the previous
implementation was therefore erroneously determining the size. There is
at least one known caller in core-mm, move_huge_pte(), which may call
huge_ptep_get_and_clear() for a non-present pte. So we must be robust to
this case. Additionally the "regular" ptep_get_and_clear() is robust to
being called for non-present ptes so it makes sense to follow the
behavior.
Fix this by using the new sz parameter which is now provided to the
function. Additionally when clearing each pte in a contig range, don't
gather the access and dirty bits if the pte is not present.
An alternative approach that would not require API changes would be to
store the PTE_CONT bit in a spare bit in the swap entry pte for the
non-present case. But it felt cleaner to follow other APIs' lead and
just pass in the size.
As an aside, PTE_CONT is bit 52, which corresponds to bit 40 in the swap
entry offset field (layout of non-present pte). Since hugetlb is never
swapped to disk, this field will only be populated for markers, which
always set this bit to 0 and hwpoison swap entries, which set the offset
field to a PFN; So it would only ever be 1 for a 52-bit PVA system where
memory in that high half was poisoned (I think!). So in practice, this
bit would almost always be zero for non-present ptes and we would only
clear the first entry if it was actually a contiguous block. That's
probably a less severe symptom than if it was always interpreted as 1
and cleared out potentially-present neighboring PTEs.
Cc: stable@vger.kernel.org
Fixes: 66b3923a1a ("arm64: hugetlb: add support for PTE contiguous bit")
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/r/20250226120656.2400136-3-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 02410ac72a upstream.
In order to fix a bug, arm64 needs to be told the size of the huge page
for which the huge_pte is being cleared in huge_ptep_get_and_clear().
Provide for this by adding an `unsigned long sz` parameter to the
function. This follows the same pattern as huge_pte_clear() and
set_huge_pte_at().
This commit makes the required interface modifications to the core mm as
well as all arches that implement this function (arm64, loongarch, mips,
parisc, powerpc, riscv, s390, sparc). The actual arm64 bug will be fixed
in a separate commit.
Cc: stable@vger.kernel.org
Fixes: 66b3923a1a ("arm64: hugetlb: add support for PTE contiguous bit")
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> # s390
Link: https://lore.kernel.org/r/20250226120656.2400136-2-ryan.roberts@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit aa5119c36d upstream.
The number of valid bits in SAMA7G5 ADC channel data register are 16.
Hence changing the realbits value to 16
Fixes: 840bf6cb98 ("iio: adc: at91-sama5d2_adc: add support for sama7g5 device")
Signed-off-by: Nayab Sayed <nayabbasha.sayed@microchip.com>
Link: https://patch.msgid.link/20250115-fix-sama7g5-adc-realbits-v2-1-58a6e4087584@microchip.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 21d7241faf upstream.
Channel configuration doesn't work as expected.
For FIELD_PREP the bit mask is needed and not the bit number.
Fixes: 874bbd1219 ("iio: adc: ad7192: Use bitfield access macros")
Signed-off-by: Markus Burri <markus.burri@mt.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20250124150703.97848-1-markus.burri@mt.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e17b9f20da upstream.
Clear reset status flag, to keep error status register clean after reset
(ad3552r manual, rev B table 38).
Reset error flag was left to 1, so debugging registers, the "Error
Status Register" was dirty (0x01). It is important to clear this bit, so
if there is any reset event over normal working mode, it is possible to
detect it.
Fixes: 8f2b54824b ("drivers:iio:dac: Add AD3552R driver support")
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
Link: https://patch.msgid.link/20250125-wip-bl-ad3552r-clear-reset-v2-1-aa3a27f3ff8c@baylibre.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a96d3e2bec upstream.
The two provided max_scale_nano values must be multiplied by 100 and 10
respectively to achieve nano units. According to the comments:
Max scale for apds0306 is 16.326432 → the fractional part is 0.326432,
which is 326432000 in NANO. The current value is 3264320.
Max scale for apds0306-065 is 14.09721 → the fractional part is 0.09712,
which is 97120000 in NANO. The current value is 9712000.
Update max_scale_nano initialization to use the right NANO fractional
parts.
Cc: stable@vger.kernel.org
Fixes: 620d1e6c7a ("iio: light: Add support for APDS9306 Light Sensor")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Tested-by: subhajit.ghosh@tweaklogic.com
Link: https://patch.msgid.link/20250112-apds9306_nano_vals-v1-1-82fb145d0b16@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cc2c3540d9 upstream.
When a weak pull-up is present on the SDO line, regmap_update_bits fails
to write both the SOFTRESET and SDOACTIVE bits because it incorrectly
reads them as already set.
Since the soft reset disables the SDO line, performing a
read-modify-write operation on ADI_SPI_CONFIG_A to enable the SDO line
doesn't make sense. This change directly writes to the register instead
of using regmap_update_bits.
Fixes: f34fe888ad ("iio:filter:admv8818: add support for ADMV8818")
Signed-off-by: Sam Winchenbach <swinchenbach@arka.org>
Link: https://patch.msgid.link/SA1P110MB106904C961B0F3FAFFED74C0BCF5A@SA1P110MB1069.NAMP110.PROD.OUTLOOK.COM
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 819cec1dc4 upstream.
In the "pmcmd_ioctl" function, three memory objects allocated by
kmalloc are initialized by "hcall_get_cpu_state", which are then
copied to user space. The initializer is indeed implemented in
"acrn_hypercall2" (arch/x86/include/asm/acrn.h). There is a risk of
information leakage due to uninitialized bytes.
Fixes: 3d679d5aec ("virt: acrn: Introduce interfaces to query C-states and P-states allowed by hypervisor")
Signed-off-by: Haoyu Li <lihaoyu499@gmail.com>
Cc: stable <stable@kernel.org>
Acked-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20250130115811.92424-1-lihaoyu499@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 038ef0754a upstream.
The dev_id value in the GPIO lookup table must match to
the device instance name, which in this case is combined
of name and platform device ID, i.e. "spi_gpio.1". But
the table assumed that there was no platform device ID
defined, which is wrong. Fix the dev_id value accordingly.
Fixes: 9b00bc7b90 ("spi: spi-gpio: Rewrite to use GPIO descriptors")
Cc: stable <stable@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250206220311.1554075-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a321d163de upstream.
There are multiple places from where the recovery work gets scheduled
asynchronously. Also, there are multiple places where the caller waits
synchronously for the recovery to be completed. One such place is during
the PM shutdown() callback.
If the device is not alive during recovery_work, it will try to reset the
device using pci_reset_function(). This function internally will take the
device_lock() first before resetting the device. By this time, if the lock
has already been acquired, then recovery_work will get stalled while
waiting for the lock. And if the lock was already acquired by the caller
which waits for the recovery_work to be completed, it will lead to
deadlock.
This is what happened on the X1E80100 CRD device when the device died
before shutdown() callback. Driver core calls the driver's shutdown()
callback while holding the device_lock() leading to deadlock.
And this deadlock scenario can occur on other paths as well, like during
the PM suspend() callback, where the driver core would hold the
device_lock() before calling driver's suspend() callback. And if the
recovery_work was already started, it could lead to deadlock. This is also
observed on the X1E80100 CRD.
So to fix both issues, use pci_try_reset_function() in recovery_work. This
function first checks for the availability of the device_lock() before
trying to reset the device. If the lock is available, it will acquire it
and reset the device. Otherwise, it will return -EAGAIN. If that happens,
recovery_work will fail with the error message "Recovery failed" as not
much could be done.
Cc: stable@vger.kernel.org # 5.12
Reported-by: Johan Hovold <johan@kernel.org>
Closes: https://lore.kernel.org/mhi/Z1me8iaK7cwgjL92@hovoldconsulting.com
Fixes: 7389337f0a ("mhi: pci_generic: Add suspend/resume/recovery procedure")
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Analyzed-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/mhi/Z2KKjWY2mPen6GPL@hovoldconsulting.com/
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/20250108-mhi_recovery_fix-v1-1-a0a00a17da46@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dcb0d43ba8 upstream.
In case of interrupt delay for any reason, slim_do_transfer()
returns timeout error but the transaction ID (TID) is not freed.
This results into invalid memory access inside
qcom_slim_ngd_rx_msgq_cb() due to invalid TID.
Fix the issue by freeing the TID in slim_do_transfer() before
returning timeout error to avoid invalid memory access.
Call trace:
__memcpy_fromio+0x20/0x190
qcom_slim_ngd_rx_msgq_cb+0x130/0x290 [slim_qcom_ngd_ctrl]
vchan_complete+0x2a0/0x4a0
tasklet_action_common+0x274/0x700
tasklet_action+0x28/0x3c
_stext+0x188/0x620
run_ksoftirqd+0x34/0x74
smpboot_thread_fn+0x1d8/0x464
kthread+0x178/0x238
ret_from_fork+0x10/0x20
Code: aa0003e8 91000429 f100044a 3940002b (3800150b)
---[ end trace 0fe00bec2b975c99 ]---
Kernel panic - not syncing: Oops: Fatal exception in interrupt.
Fixes: afbdcc7c38 ("slimbus: Add messaging APIs to slimbus framework")
Cc: stable <stable@kernel.org>
Signed-off-by: Visweswara Tanuku <quic_vtanuku@quicinc.com>
Link: https://lore.kernel.org/r/20250124125740.16897-1-quic_vtanuku@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6d991f569c upstream.
When creating sysfs files fail, the allocated minor must be freed such that
it can be later reused. That is specially harmful for static minor numbers,
since those would always fail to register later on.
Fixes: 6d04d2b554 ("misc: misc_minor_alloc to use ida for all dynamic/misc dynamic minors")
Cc: stable <stable@kernel.org>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Link: https://lore.kernel.org/r/20250123123249.4081674-5-cascardo@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fdb1ada57c upstream.
The _CRS ACPI resources table has 2 entries for the host wakeup GPIO,
the first one being a regular GpioIo () resource while the second one
is a GpioInt () resource for the same pin.
The acpi_gpio_mapping table used by vsc-tp.c maps the first Gpio ()
resource to "wakeuphost-gpios" where as the second GpioInt () entry
is mapped to "wakeuphostint-gpios".
Using "wakeuphost" to request the GPIO as was done until now, means
that the gpiolib-acpi code does not know that the GPIO is active-low
as that info is only available in the GpioInt () entry.
Things were still working before due to the following happening:
1. Since the 2 entries point to the same pin they share a struct gpio_desc
2. The SPI core creates the SPI device vsc-tp.c binds to and calls
acpi_dev_gpio_irq_get(). This does use the second entry and sets
FLAG_ACTIVE_LOW in gpio_desc.flags .
3. vsc_tp_probe() requests the "wakeuphost" GPIO and inherits the
active-low flag set by acpi_dev_gpio_irq_get()
But there is a possible scenario where things do not work:
1. - 3. happen as above
4. After requesting the "wakeuphost" GPIO, the "resetfw" GPIO is requested
next, but its USB GPIO controller is not available yet, so this call
returns -EPROBE_DEFER.
5. The gpio_desc for "wakeuphost" is put() and during this the active-low
flag is cleared from gpio_desc.flags .
6. Later on vsc_tp_probe() requests the "wakeuphost" GPIO again, but now it
is not marked active-low.
The difference can also be seen in /sys/kernel/debug/gpio, which contains
the following line for this GPIO:
gpio-535 ( |wakeuphost ) in hi IRQ ACTIVE LOW
If the second scenario is hit the "ACTIVE LOW" at the end disappears and
things do not work.
Fix this by requesting the GPIO through the "wakeuphostint" mapping instead
which provides active-low info without relying on acpi_dev_gpio_irq_get()
pre-populating this info in the gpio_desc.
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2316918
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Tested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Fixes: 566f5ca976 ("mei: Add transport driver for IVSC device")
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20250214212425.84021-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 91d44c1afc upstream.
Fixed a possible UAF problem in driver_override_show() in drivers/cdx/cdx.c
This function driver_override_show() is part of DEVICE_ATTR_RW, which
includes both driver_override_show() and driver_override_store().
These functions can be executed concurrently in sysfs.
The driver_override_store() function uses driver_set_override() to
update the driver_override value, and driver_set_override() internally
locks the device (device_lock(dev)). If driver_override_show() reads
cdx_dev->driver_override without locking, it could potentially access
a freed pointer if driver_override_store() frees the string
concurrently. This could lead to printing a kernel address, which is a
security risk since DEVICE_ATTR can be read by all users.
Additionally, a similar pattern is used in drivers/amba/bus.c, as well
as many other bus drivers, where device_lock() is taken in the show
function, and it has been working without issues.
This potential bug was detected by our experimental static analysis
tool, which analyzes locking APIs and paired functions to identify
data races and atomicity violations.
Fixes: 1f86a00c11 ("bus/fsl-mc: add support for 'driver_override' in the mc-bus")
Cc: stable <stable@kernel.org>
Signed-off-by: Qiu-ji Chen <chenqiuji666@gmail.com>
Link: https://lore.kernel.org/r/20250118070833.27201-1-chenqiuji666@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f9dc8fb3af upstream.
Fix a goof where KVM sets CPUID.0x80000022.EAX to CPUID.0x80000022.EBX
instead of zeroing both when PERFMON_V2 isn't supported by KVM. In
practice, barring a buggy CPU (or vCPU model when running nested) only the
!enable_pmu case is affected, as KVM always supports PERFMON_V2 if it's
available in hardware, i.e. CPUID.0x80000022.EBX will be '0' if PERFMON_V2
is unsupported.
For the !enable_pmu case, the bug is relatively benign as KVM will refuse
to enable PMU capabilities, but a VMM that reflects KVM's supported CPUID
into the guest could inadvertently induce #GPs in the guest due to
advertising support for MSRs that KVM refuses to emulate.
Fixes: 94cdeebd82 ("KVM: x86/cpuid: Add AMD CPUID ExtPerfMonAndDbg leaf 0x80000022")
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20250304082314.472202-3-xiaoyao.li@intel.com
[sean: massage shortlog and changelog, tag for stable]
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 189ecdb3e1 upstream.
Snapshot the host's DEBUGCTL after disabling IRQs, as perf can toggle
debugctl bits from IRQ context, e.g. when enabling/disabling events via
smp_call_function_single(). Taking the snapshot (long) before IRQs are
disabled could result in KVM effectively clobbering DEBUGCTL due to using
a stale snapshot.
Cc: stable@vger.kernel.org
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250227222411.3490595-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 433265870a upstream.
Manually load the guest's DEBUGCTL prior to VMRUN (and restore the host's
value on #VMEXIT) if it diverges from the host's value and LBR
virtualization is disabled, as hardware only context switches DEBUGCTL if
LBR virtualization is fully enabled. Running the guest with the host's
value has likely been mildly problematic for quite some time, e.g. it will
result in undesirable behavior if BTF diverges (with the caveat that KVM
now suppresses guest BTF due to lack of support).
But the bug became fatal with the introduction of Bus Lock Trap ("Detect"
in kernel paralance) support for AMD (commit 408eb7417a
("x86/bus_lock: Add support for AMD")), as a bus lock in the guest will
trigger an unexpected #DB.
Note, suppressing the bus lock #DB, i.e. simply resuming the guest without
injecting a #DB, is not an option. It wouldn't address the general issue
with DEBUGCTL, e.g. for things like BTF, and there are other guest-visible
side effects if BusLockTrap is left enabled.
If BusLockTrap is disabled, then DR6.BLD is reserved-to-1; any attempts to
clear it by software are ignored. But if BusLockTrap is enabled, software
can clear DR6.BLD:
Software enables bus lock trap by setting DebugCtl MSR[BLCKDB] (bit 2)
to 1. When bus lock trap is enabled, ... The processor indicates that
this #DB was caused by a bus lock by clearing DR6[BLD] (bit 11). DR6[11]
previously had been defined to be always 1.
and clearing DR6.BLD is "sticky" in that it's not set (i.e. lowered) by
other #DBs:
All other #DB exceptions leave DR6[BLD] unmodified
E.g. leaving BusLockTrap enable can confuse a legacy guest that writes '0'
to reset DR6.
Reported-by: rangemachine@gmail.com
Reported-by: whanos@sergal.fun
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219787
Closes: https://lore.kernel.org/all/bug-219787-28872@https.bugzilla.kernel.org%2F
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: stable@vger.kernel.org
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250227222411.3490595-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fb71c79593 upstream.
Move KVM's snapshot of DEBUGCTL to kvm_vcpu_arch and take the snapshot in
common x86, so that SVM can also use the snapshot.
Opportunistically change the field to a u64. While bits 63:32 are reserved
on AMD, not mentioned at all in Intel's SDM, and managed as an "unsigned
long" by the kernel, DEBUGCTL is an MSR and therefore a 64-bit value.
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Cc: stable@vger.kernel.org
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250227222411.3490595-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d0eac42f5c upstream.
Mark BTF as reserved in DEBUGCTL on AMD, as KVM doesn't actually support
BTF, and fully enabling BTF virtualization is non-trivial due to
interactions with the emulator, guest_debug, #DB interception, nested SVM,
etc.
Don't inject #GP if the guest attempts to set BTF, as there's no way to
communicate lack of support to the guest, and instead suppress the flag
and treat the WRMSR as (partially) unsupported.
In short, make KVM behave the same on AMD and Intel (VMX already squashes
BTF).
Note, due to other bugs in KVM's handling of DEBUGCTL, the only way BTF
has "worked" in any capacity is if the guest simultaneously enables LBRs.
Reported-by: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: stable@vger.kernel.org
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250227222411.3490595-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee89e80133 upstream.
Drop bits 5:2 from the guest's effective DEBUGCTL value, as AMD changed
the architectural behavior of the bits and broke backwards compatibility.
On CPUs without BusLockTrap (or at least, in APMs from before ~2023),
bits 5:2 controlled the behavior of external pins:
Performance-Monitoring/Breakpoint Pin-Control (PBi)—Bits 5:2, read/write.
Software uses thesebits to control the type of information reported by
the four external performance-monitoring/breakpoint pins on the
processor. When a PBi bit is cleared to 0, the corresponding external pin
(BPi) reports performance-monitor information. When a PBi bit is set to
1, the corresponding external pin (BPi) reports breakpoint information.
With the introduction of BusLockTrap, presumably to be compatible with
Intel CPUs, AMD redefined bit 2 to be BLCKDB:
Bus Lock #DB Trap (BLCKDB)—Bit 2, read/write. Software sets this bit to
enable generation of a #DB trap following successful execution of a bus
lock when CPL is > 0.
and redefined bits 5:3 (and bit 6) as "6:3 Reserved MBZ".
Ideally, KVM would treat bits 5:2 as reserved. Defer that change to a
feature cleanup to avoid breaking existing guest in LTS kernels. For now,
drop the bits to retain backwards compatibility (of a sort).
Note, dropping bits 5:2 is still a guest-visible change, e.g. if the guest
is enabling LBRs *and* the legacy PBi bits, then the state of the PBi bits
is visible to the guest, whereas now the guest will always see '0'.
Reported-by: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: stable@vger.kernel.org
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250227222411.3490595-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b2653cd3b7 upstream.
When running SEV-SNP guests on a CPU that supports DebugSwap, always save
the host's DR0..DR3 mask MSR values irrespective of whether or not
DebugSwap is enabled, to ensure the host values aren't clobbered by the
CPU. And for now, also save DR0..DR3, even though doing so isn't
necessary (see below).
SVM_VMGEXIT_AP_CREATE is deeply flawed in that it allows the *guest* to
create a VMSA with guest-controlled SEV_FEATURES. A well behaved guest
can inform the hypervisor, i.e. KVM, of its "requested" features, but on
CPUs without ALLOWED_SEV_FEATURES support, nothing prevents the guest from
lying about which SEV features are being enabled (or not!).
If a misbehaving guest enables DebugSwap in a secondary vCPU's VMSA, the
CPU will load the DR0..DR3 mask MSRs on #VMEXIT, i.e. will clobber the
MSRs with '0' if KVM doesn't save its desired value.
Note, DR0..DR3 themselves are "ok", as DR7 is reset on #VMEXIT, and KVM
restores all DRs in common x86 code as needed via hw_breakpoint_restore().
I.e. there is no risk of host DR0..DR3 being clobbered (when it matters).
However, there is a flaw in the opposite direction; because the guest can
lie about enabling DebugSwap, i.e. can *disable* DebugSwap without KVM's
knowledge, KVM must not rely on the CPU to restore DRs. Defer fixing
that wart, as it's more of a documentation issue than a bug in the code.
Note, KVM added support for DebugSwap on commit d1f85fbe83 ("KVM: SEV:
Enable data breakpoints in SEV-ES"), but that is not an appropriate Fixes,
as the underlying flaw exists in hardware, not in KVM. I.e. all kernels
that support SEV-SNP need to be patched, not just kernels with KVM's full
support for DebugSwap (ignoring that DebugSwap support landed first).
Opportunistically fix an incorrect statement in the comment; on CPUs
without DebugSwap, the CPU does NOT save or load debug registers, i.e.
Fixes: e366f92ea9 ("KVM: SEV: Support SEV-SNP AP Creation NAE event")
Cc: stable@vger.kernel.org
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Alexey Kardashevskiy <aik@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20250227012541.3234589-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit be45bc4eff upstream.
Enable/disable local IRQs, i.e. set/clear RFLAGS.IF, in the common
svm_vcpu_enter_exit() just after/before guest_state_{enter,exit}_irqoff()
so that VMRUN is not executed in an STI shadow. AMD CPUs have a quirk
(some would say "bug"), where the STI shadow bleeds into the guest's
intr_state field if a #VMEXIT occurs during injection of an event, i.e. if
the VMRUN doesn't complete before the subsequent #VMEXIT.
The spurious "interrupts masked" state is relatively benign, as it only
occurs during event injection and is transient. Because KVM is already
injecting an event, the guest can't be in HLT, and if KVM is querying IRQ
blocking for injection, then KVM would need to force an immediate exit
anyways since injecting multiple events is impossible.
However, because KVM copies int_state verbatim from vmcb02 to vmcb12, the
spurious STI shadow is visible to L1 when running a nested VM, which can
trip sanity checks, e.g. in VMware's VMM.
Hoist the STI+CLI all the way to C code, as the aforementioned calls to
guest_state_{enter,exit}_irqoff() already inform lockdep that IRQs are
enabled/disabled, and taking a fault on VMRUN with RFLAGS.IF=1 is already
possible. I.e. if there's kernel code that is confused by running with
RFLAGS.IF=1, then it's already a problem. In practice, since GIF=0 also
blocks NMIs, the only change in exposure to non-KVM code (relative to
surrounding VMRUN with STI+CLI) is exception handling code, and except for
the kvm_rebooting=1 case, all exception in the core VM-Enter/VM-Exit path
are fatal.
Use the "raw" variants to enable/disable IRQs to avoid tracing in the
"no instrumentation" code; the guest state helpers also take care of
tracing IRQ state.
Oppurtunstically document why KVM needs to do STI in the first place.
Reported-by: Doug Covelli <doug.covelli@broadcom.com>
Closes: https://lore.kernel.org/all/CADH9ctBs1YPmE4aCfGPNBwA10cA8RuAk2gO7542DjMZgs4uzJQ@mail.gmail.com
Fixes: f14eec0a32 ("KVM: SVM: move more vmentry code to assembly")
Cc: stable@vger.kernel.org
Reviewed-by: Jim Mattson <jmattson@google.com>
Link: https://lore.kernel.org/r/20250224165442.2338294-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c133ec0e57 upstream.
Raspberry Pi is a major user of those chips and they discovered a bug -
when the end of a transfer ring segment is reached, up to four TRBs can
be prefetched from the next page even if the segment ends with link TRB
and on page boundary (the chip claims to support standard 4KB pages).
It also appears that if the prefetched TRBs belong to a different ring
whose doorbell is later rung, they may be used without refreshing from
system RAM and the endpoint will stay idle if their cycle bit is stale.
Other users complain about IOMMU faults on x86 systems, unsurprisingly.
Deal with it by using existing quirk which allocates a dummy page after
each transfer ring segment. This was seen to resolve both problems. RPi
came up with a more efficient solution, shortening each segment by four
TRBs, but it complicated the driver and they ditched it for this quirk.
Also rename the quirk and add VL805 device ID macro.
Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
Link: https://github.com/raspberrypi/linux/issues/4685
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=215906
CC: stable@vger.kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20250225095927.2512358-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1bae8729e5 upstream.
The following FFI types are replaced compared to `core::ffi`:
1. `char` type is now always mapped to `u8`, since kernel uses
`-funsigned-char` on the C code. `core::ffi` maps it to platform
default ABI, which can be either signed or unsigned.
2. `long` is now always mapped to `isize`. It's very common in the
kernel to use `long` to represent a pointer-sized integer, and in
fact `intptr_t` is a typedef of `long` in the kernel. Enforce this
mapping rather than mapping to `i32/i64` depending on platform can
save us a lot of unnecessary casts.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240913213041.395655-5-gary@garyguo.net
[ Moved `uaccess` changes from the next commit, since they were
irrefutable patterns that Rust >= 1.82.0 warns about. Reworded
slightly and reformatted a few documentation comments. Rebased on
top of `rust-next`. Added the removal of two casts to avoid Clippy
warnings. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 27c7518e7f upstream.
In the last kernel cycle we migrated most of the `core::ffi` cases in
commit d072acda48 ("rust: use custom FFI integer types"):
Currently FFI integer types are defined in libcore. This commit
creates the `ffi` crate and asks bindgen to use that crate for FFI
integer types instead of `core::ffi`.
This commit is preparatory and no type changes are made in this
commit yet.
Finish now the few remaining/new cases so that we perform the actual
remapping in the next commit as planned.
Acked-by: Jocelyn Falempe <jfalempe@redhat.com> # drm
Link: https://lore.kernel.org/rust-for-linux/CANiq72m_rg42SvZK=bF2f0yEoBLVA33UBhiAsv8THhVu=G2dPA@mail.gmail.com/
Link: https://lore.kernel.org/all/cc9253fa-9d5f-460b-9841-94948fb6580c@redhat.com/
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 976e7e9bdc upstream.
For the ACPI backend of UCSI the UCSI "registers" are just a memory copy
of the register values in an opregion. The ACPI implementation in the
BIOS ensures that the opregion contents are synced to the embedded
controller and it ensures that the registers (in particular CCI) are
synced back to the opregion on notifications. While there is an ACPI call
that syncs the actual registers to the opregion there is rarely a need to
do this and on some ACPI implementations it actually breaks in various
interesting ways.
The only reason to force a sync from the embedded controller is to poll
CCI while notifications are disabled. Only the ucsi core knows if this
is the case and guessing based on the current command is suboptimal, i.e.
leading to the following spurious assertion splat:
WARNING: CPU: 3 PID: 76 at drivers/usb/typec/ucsi/ucsi.c:1388 ucsi_reset_ppm+0x1b4/0x1c0 [typec_ucsi]
CPU: 3 UID: 0 PID: 76 Comm: kworker/3:0 Not tainted 6.12.11-200.fc41.x86_64 #1
Hardware name: LENOVO 21D0/LNVNB161216, BIOS J6CN45WW 03/17/2023
Workqueue: events_long ucsi_init_work [typec_ucsi]
RIP: 0010:ucsi_reset_ppm+0x1b4/0x1c0 [typec_ucsi]
Call Trace:
<TASK>
ucsi_init_work+0x3c/0xac0 [typec_ucsi]
process_one_work+0x179/0x330
worker_thread+0x252/0x390
kthread+0xd2/0x100
ret_from_fork+0x34/0x50
ret_from_fork_asm+0x1a/0x30
</TASK>
Thus introduce a ->poll_cci() method that works like ->read_cci() with an
additional forced sync and document that this should be used when polling
with notifications disabled. For all other backends that presumably don't
have this issue use the same implementation for both methods.
Fixes: fa48d7e816 ("usb: typec: ucsi: Do not call ACPI _DSM method for UCSI read operations")
Cc: stable <stable@kernel.org>
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Tested-by: Fedor Pchelkin <boddah8794@gmail.com>
Signed-off-by: Fedor Pchelkin <boddah8794@gmail.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250217105442.113486-2-boddah8794@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dfc1b168a8 upstream.
The userprog infrastructure links objects files through $(CC).
Either explicitly by manually calling $(CC) on multiple object files or
implicitly by directly compiling a source file to an executable.
The documentation at Documentation/kbuild/llvm.rst indicates that ld.lld
would be used for linking if LLVM=1 is specified.
However clang instead will use either a globally installed cross linker
from $PATH called ${target}-ld or fall back to the system linker, which
probably does not support crosslinking.
For the normal kernel build this is not an issue because the linker is
always executed directly, without the compiler being involved.
Explicitly pass --ld-path to clang so $(LD) is respected.
As clang 13.0.1 is required to build the kernel, this option is available.
Fixes: 7f3a59db27 ("kbuild: add infrastructure to build userspace programs")
Cc: stable@vger.kernel.org # needs wrapping in $(cc-option) for < 6.9
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8e812e9355 upstream.
If the USB configuration is not valid, then avoid checking for
bmAttributes to prevent null pointer deference.
Cc: stable <stable@kernel.org>
Fixes: 40e89ff575 ("usb: gadget: Set self-powered based on MaxPower and bmAttributes")
Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250224085604.417327-1-prashanth.k@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c783e1258f upstream.
cdev->config might be NULL, so check it before dereferencing.
CC: stable <stable@kernel.org>
Fixes: 40e89ff575 ("usb: gadget: Set self-powered based on MaxPower and bmAttributes")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250220120314.3614330-1-m.szyprowski@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 40e89ff575 upstream.
Currently the USB gadget will be set as bus-powered based solely
on whether its bMaxPower is greater than 100mA, but this may miss
devices that may legitimately draw less than 100mA but still want
to report as bus-powered. Similarly during suspend & resume, USB
gadget is incorrectly marked as bus/self powered without checking
the bmAttributes field. Fix these by configuring the USB gadget
as self or bus powered based on bmAttributes, and explicitly set
it as bus-powered if it draws more than 100mA.
Cc: stable <stable@kernel.org>
Fixes: 5e5caf4fa8 ("usb: gadget: composite: Inform controller driver of self-powered")
Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250217120328.2446639-1-prashanth.k@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d6b82dafd1 upstream.
During probe, the TCPC alert interrupts are getting masked to
avoid unwanted interrupts during chip setup: this is ok to do
but there is no unmasking happening at any later time, which
means that the chip will not raise any interrupt, essentially
making it not functional as, while internally it does perform
all of the intended functions, it won't signal anything to the
outside.
Unmask the alert interrupts to fix functionality.
Fixes: ce08eaeb63 ("staging: typec: rt1711h typec chip driver")
Cc: stable <stable@kernel.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20250219114700.41700-1-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bf4f9ae1cb upstream.
It is observed that on some systems an initial PPM reset during the boot
phase can trigger a timeout:
[ 6.482546] ucsi_acpi USBC000:00: failed to reset PPM!
[ 6.482551] ucsi_acpi USBC000:00: error -ETIMEDOUT: PPM init failed
Still, increasing the timeout value, albeit being the most straightforward
solution, eliminates the problem: the initial PPM reset may take up to
~8000-10000ms on some Lenovo laptops. When it is reset after the above
period of time (or even if ucsi_reset_ppm() is not called overall), UCSI
works as expected.
Moreover, if the ucsi_acpi module is loaded/unloaded manually after the
system has booted, reading the CCI values and resetting the PPM works
perfectly, without any timeout. Thus it's only a boot-time issue.
The reason for this behavior is not clear but it may be the consequence
of some tricks that the firmware performs or be an actual firmware bug.
As a workaround, increase the timeout to avoid failing the UCSI
initialization prematurely.
Fixes: b1b59e1607 ("usb: typec: ucsi: Increase command completion timeout value")
Cc: stable <stable@kernel.org>
Signed-off-by: Fedor Pchelkin <boddah8794@gmail.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250217105442.113486-3-boddah8794@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
