Four sysfs show() callbacks in hv-gpci take get_cpu_var(hv_gpci_reqb)
(which calls preempt_disable()) but only call the matching put_cpu_var()
on the error path under the 'out:' label. Every successful read leaks
one preempt_disable():
processor_bus_topology_show()
processor_config_show()
affinity_domain_via_virtual_processor_show()
affinity_domain_via_domain_show()
(affinity_domain_via_partition_show() was already correct.)
On a CONFIG_PREEMPT=y kernel, repeated reads raise preempt_count and
eventually return to userspace with preemption still disabled. The
next user-mode page fault then hits faulthandler_disabled() == 1,
gets forced to SIGSEGV, and the resulting coredump trips
'BUG: scheduling while atomic' in call_usermodehelper_exec ->
wait_for_completion_state -> schedule:
BUG: scheduling while atomic: <task>/<pid>/0x00000004
...
__schedule_bug+0x6c/0x90
__schedule+0x58c/0x13a0
schedule+0x48/0x1a0
schedule_timeout+0x104/0x170
wait_for_completion_state+0x16c/0x330
call_usermodehelper_exec+0x254/0x2d0
vfs_coredump+0x1050/0x2590
get_signal+0xb9c/0xc80
do_notify_resume+0xf8/0x470
Add an out_success label that calls put_cpu_var() before returning
the byte count, mirroring affinity_domain_via_partition_show().
Fixes: 71f1c39647 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show processor bus topology information")
Fixes: 1a160c2a13 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show processor config information")
Fixes: 71a7ccb478 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show affinity domain via virtual processor information")
Fixes: a69a57cac1 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show affinity domain via domain information")
Signed-off-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260508041256.3447113-1-aboorvad@linux.ibm.com
The core-book3s PMU sampling code validates the SIER TYPE field
when PERF_SAMPLE_DATA_SRC is requested. The SIER TYPE field
indicates the instruction type and is only valid for
random sampling (marked events). To handle cases observed where
SIER TYPE could be zero even for marked events,validation was
added to drop such samples and increment event->lost_samples.
However, this validation was applied to all samples,
including continuous sampling. In continuous sampling mode,
the PMU does not set the SIER TYPE field, so it remains zero.
As a result, valid continuous samples were incorrectly
treated as invalid and dropped. Fixed this by gating the
SIER TYPE validation with mark_event, so the check runs only
for marked (random) events. Continuous samples now skip this
check and are recorded normally in the final data recording path.
Fixes: 2ffb26afa6 ("arch/powerpc/perf: Check the instruction type before creating sample with perf_mem_data_src")
Signed-off-by: Shivani Nittor <shivani@linux.ibm.com>
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.ibm.com>
[Maddy: Fixed reviewed-by tag]
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260421150628.96500-1-shivani@linux.ibm.com
It may happen that mm is already released, which leads to kernel panic.
This adds the NULL check for current->mm, similarly to
commit 20afc60f89 ("x86, perf: Check that current->mm is alive before getting user callchain").
I was getting this panic when running a profiling BPF program
(profile.py from bcc-tools):
[26215.051935] Kernel attempted to read user page (588) - exploit attempt? (uid: 0)
[26215.051950] BUG: Kernel NULL pointer dereference on read at 0x00000588
[26215.051952] Faulting instruction address: 0xc00000000020fac0
[26215.051957] Oops: Kernel access of bad area, sig: 11 [#1]
[...]
[26215.052049] Call Trace:
[26215.052050] [c000000061da6d30] [c00000000020fc10] perf_callchain_user_64+0x2d0/0x490 (unreliable)
[26215.052054] [c000000061da6dc0] [c00000000020f92c] perf_callchain_user+0x1c/0x30
[26215.052057] [c000000061da6de0] [c0000000005ab2a0] get_perf_callchain+0x100/0x360
[26215.052063] [c000000061da6e70] [c000000000573bc8] bpf_get_stackid+0x88/0xf0
[26215.052067] [c000000061da6ea0] [c008000000042258] bpf_prog_16d4ab9ab662f669_do_perf_event+0xf8/0x274
[...]
In addition, move storing the top-level stack entry to generic
perf_callchain_user to make sure the top-evel entry is always captured,
even if current->mm is NULL.
Fixes: 20002ded4d ("perf_counter: powerpc: Add callchain support")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Tested-by: Qiao Zhao <qzhao@redhat.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Reviewed-by: Saket Kumar Bhaskar <skb99@linux.ibm.com>
[Maddy: fixed message to avoid checkpatch format style error]
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260309144045.169427-1-vmalik@redhat.com
This converts some of the visually simpler cases that have been split
over multiple lines. I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.
Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script. I probably had made it a bit _too_ trivial.
So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.
The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Handle the case when the aux buffer is going to be full and
data needs to be written to the data file. perf_aux_output_begin()
function checks if there is enough space depending on the values of
aux_wakeup and aux_watermark which is part of "struct perf_buffer".
Inorder to maintain where to write to aux buffer, add two fields
to "struct vpa_pmu_buf". Field "threshold" to indicate total possible
DTL entries that can be contained in aux buffer and field "full" to
indicate anytime when buffer is full. In perf_aux_output_end, there
is check to see if wake up is needed based on aux head value.
In vpa_dtl_capture_aux(), check if there is enough space to contain the
DTL data. If not, save the data for available memory and set full to true.
Set head of private aux to zero when buffer is full so that next data
will be copied to beginning of the buffer. The address used for copying
to aux is "aux_copy_buf + buf->head". So once buffer is full, set head
to zero, so that next time it will be written from start of the buffer.
Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Tested-by: Tejas Manhas <tejas05@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250915102947.26681-7-atrajeev@linux.ibm.com
vpa dtl pmu has one hrtimer added per vpa-dtl pmu thread. When the
hrtimer expires, in the timer handler, code is added to save the DTL
data to perf event record via vpa_dtl_capture_aux() function.
The DTL (Dispatch Trace Log) contains information
about dispatch/preempt, enqueue time etc. We directly copy the DTL
buffer data as part of auxiliary buffer. Data will be written to
disk only when the allocated buffer is full.
By this approach, all the DTL data will be present as-is in the
perf.data. The data will be post-processed in perf tools side when doing
perf report/perf script and this will avoid time taken to create samples
in the kernel space.
To corelate each DTL entry with other events across CPU's, we need to
map timebase from "struct dtl_entry" which phyp provides with boot
timebase. This also needs timebase frequency. Define "struct boottb_freq"
to save these details.
Added changes to capture the Dispatch Trace Log details to AUX buffer
in vpa_dtl_dump_sample_data(). Boot timebase and frequency needs to be
saved only at once, added field to indicate this as part of
"vpa_pmu_buf" structure.
perf_aux_output_begin: This function is called before writing to AUX
area. This returns the pointer to aux area private structure, ie
"struct vpa_pmu_buf". The function obtains the output handle
(used in perf_aux_output_end). when capture completes in
vpa_dtl_capture_aux(), call perf_aux_output_end() to commit the recorded
data. perf_aux_output_end() is called to move the aux->head of
"struct perf_buffer" to indicate size of data in aux buffer.
aux_tail will be moved in perf tools side when writing the data from
aux buffer to perf.data file in disk.
It is responsiblity of PMU driver to make sure data is copied between
perf_aux_output_begin and perf_aux_output_end.
Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Tested-by: Tejas Manhas <tejas05@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250915102947.26681-6-atrajeev@linux.ibm.com
vpa dtl pmu has one hrtimer added per vpa-dtl pmu thread. When the
hrtimer expires, in the timer handler, code is added to save the DTL
data to perf event record. DTL (Dispatch Trace Log) contains information
about dispatch/preempt, enqueue time etc. We directly copy the DTL
buffer data as part of auxiliary buffer and it will be postprocessed
later. To enable the support for aux buffer, add the PMU callbacks for
setup_aux and free_aux.
In setup_aux, set up pmu-private data structures for an AUX
area. rb_alloc_aux uses "alloc_pages_node" and returns pointer to each
page address. Map these pages to contiguous space using vmap and use
that as base address. The aux private data structure ie,
"struct vpa_pmu_buf" mainly saves:
1. buf->base: aux buffer base address
2. buf->head: offset from base address where data will be written to.
3. buf->size: Size of allocated memory
free_aux will free pmu-private AUX data structures.
Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Tested-by: Tejas Manhas <tejas05@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250915102947.26681-5-atrajeev@linux.ibm.com
The pseries Shared Processor Logical Partition(SPLPAR) machines
can retrieve a log of dispatch and preempt events from the
hypervisor using data from Disptach Trace Log(DTL) buffer.
With this information, user can retrieve when and why each dispatch &
preempt has occurred. Added an interface to expose the Virtual Processor
Area(VPA) DTL counters via perf.
The following events are available and exposed in sysfs:
vpa_dtl/dtl_cede/ - Trace voluntary (OS initiated) virtual processor waits
vpa_dtl/dtl_preempt/ - Trace time slice preempts
vpa_dtl/dtl_fault/ - Trace virtual partition memory page faults.
vpa_dtl/dtl_all/ - Trace all (dtl_cede/dtl_preempt/dtl_fault)
Added interface defines supported event list, config fields for the
event attributes and their corresponding bit values which are exported
via sysfs. User could use the standard perf tool to access perf events
exposed via vpa-dtl pmu.
The VPA DTL PMU counters do not interrupt on overflow or generate any
PMI interrupts. Therefore, the kernel needs to poll the counters, added
hrtimer code to do that. The timer interval can be provided by user via
sample_period field in nano seconds. There is one hrtimer added per
vpa-dtl pmu thread.
To ensure there are no other conflicting dtl users (example: debugfs dtl
or /proc/powerpc/vcpudispatch_stats), interface added code to use
"down_write_trylock" call to take the dtl_access_lock. The dtl_access_lock
is defined in dtl.h file. Also added global reference count variable called
"dtl_global_refc", to ensure dtl data can be captured per-cpu. Code also
added global lock called "dtl_global_lock" to avoid race condition.
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Tested-by: Tejas Manhas <tejas05@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250915102947.26681-3-atrajeev@linux.ibm.com
Pull powerpc updates from Madhavan Srinivasan:
- CONFIG_HZ changes to move the base_slice from 10ms to 1ms
- Patchset to move some of the mutex handling to lock guard
- Expose secvars relevant to the key management mode
- Misc cleanups and fixes
Thanks to Ankit Chauhan, Christophe Leroy, Donet Tom, Gautam Menghani,
Haren Myneni, Johan Korsnes, Madadi Vineeth Reddy, Paul Mackerras,
Shrikanth Hegde, Srish Srinivasan, Thomas Fourier, Thomas Huth, Thomas
Weißschuh, Souradeep, Amit Machhiwal, R Nageswara Sastry, Venkat Rao
Bagalkote, Andrew Donnellan, Greg Kroah-Hartman, Mimi Zohar, Mukesh
Kumar Chaurasiya, Nayna Jain, Ritesh Harjani (IBM), Sourabh Jain, Srikar
Dronamraju, Stefan Berger, Tyrel Datwyler, and Kowshik Jois.
* tag 'powerpc-6.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (23 commits)
arch/powerpc: Remove .interp section in vmlinux
powerpc: Drop GPL boilerplate text with obsolete FSF address
powerpc: Don't use %pK through printk
arch: powerpc: defconfig: Drop obsolete CONFIG_NET_CLS_TCINDEX
misc: ocxl: Replace scnprintf() with sysfs_emit() in sysfs show functions
integrity/platform_certs: Allow loading of keys in the static key management mode
powerpc/secvar: Expose secvars relevant to the key management mode
powerpc/pseries: Correct secvar format representation for static key management
(powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer
powerpc: floppy: Add missing checks after DMA map
book3s64/radix : Optimize vmemmap start alignment
book3s64/radix : Handle error conditions properly in radix_vmemmap_populate
powerpc/pseries/dlpar: Search DRC index from ibm,drc-indexes for IO add
KVM: PPC: Book3S HV: Add H_VIRT mapping for tracing exits
powerpc: sysdev: use lock guard for mutex
powerpc: powernv: ocxl: use lock guard for mutex
powerpc: book3s: vas: use lock guard for mutex
powerpc: fadump: use lock guard for mutex
powerpc: rtas: use lock guard for mutex
powerpc: eeh: use lock guard for mutex
...
Pull perf events updates from Ingo Molnar:
"Core & generic-arch updates:
- Add support for dynamic constraints and propagate it to the Intel
driver (Kan Liang)
- Fix & enhance driver-specific throttling support (Kan Liang)
- Record sample last_period before updating on the x86 and PowerPC
platforms (Mark Barnett)
- Make perf_pmu_unregister() usable (Peter Zijlstra)
- Unify perf_event_free_task() / perf_event_exit_task_context()
(Peter Zijlstra)
- Simplify perf_event_release_kernel() and perf_event_free_task()
(Peter Zijlstra)
- Allocate non-contiguous AUX pages by default (Yabin Cui)
Uprobes updates:
- Add support to emulate NOP instructions (Jiri Olsa)
- selftests/bpf: Add 5-byte NOP uprobe trigger benchmark (Jiri Olsa)
x86 Intel PMU enhancements:
- Support Intel Auto Counter Reload [ACR] (Kan Liang)
- Add PMU support for Clearwater Forest (Dapeng Mi)
- Arch-PEBS preparatory changes: (Dapeng Mi)
- Parse CPUID archPerfmonExt leaves for non-hybrid CPUs
- Decouple BTS initialization from PEBS initialization
- Introduce pairs of PEBS static calls
x86 AMD PMU enhancements:
- Use hrtimer for handling overflows in the AMD uncore driver
(Sandipan Das)
- Prevent UMC counters from saturating (Sandipan Das)
Fixes and cleanups:
- Fix put_ctx() ordering (Frederic Weisbecker)
- Fix irq work dereferencing garbage (Frederic Weisbecker)
- Misc fixes and cleanups (Changbin Du, Frederic Weisbecker, Ian
Rogers, Ingo Molnar, Kan Liang, Peter Zijlstra, Qing Wang, Sandipan
Das, Thorsten Blum)"
* tag 'perf-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
perf/headers: Clean up <linux/perf_event.h> a bit
perf/uapi: Clean up <uapi/linux/perf_event.h> a bit
perf/uapi: Fix PERF_RECORD_SAMPLE comments in <uapi/linux/perf_event.h>
mips/perf: Remove driver-specific throttle support
xtensa/perf: Remove driver-specific throttle support
sparc/perf: Remove driver-specific throttle support
loongarch/perf: Remove driver-specific throttle support
csky/perf: Remove driver-specific throttle support
arc/perf: Remove driver-specific throttle support
alpha/perf: Remove driver-specific throttle support
perf/apple_m1: Remove driver-specific throttle support
perf/arm: Remove driver-specific throttle support
s390/perf: Remove driver-specific throttle support
powerpc/perf: Remove driver-specific throttle support
perf/x86/zhaoxin: Remove driver-specific throttle support
perf/x86/amd: Remove driver-specific throttle support
perf/x86/intel: Remove driver-specific throttle support
perf: Only dump the throttle log for the leader
perf: Fix the throttle logic for a group
perf/core: Add the is_event_in_freq_mode() helper to simplify the code
...
Update 'kvm-hv-pmu.c' to add five new perf-events mapped to the five
Hostwide counters. Since these newly introduced perf events are at system
wide scope and can be read from any L1-Lpar CPU, 'kvmppc_pmu' scope and
capabilities are updated appropriately.
Also introduce two new helpers. First is kvmppc_update_l0_stats() that uses
the infrastructure introduced in previous patches to issues the
H_GUEST_GET_STATE hcall L0-PowerVM to fetch guest-state-buffer holding the
latest values of these counters which is then parsed and 'l0_stats'
variable updated.
Second helper is kvmppc_pmu_event_update() which is called from
'kvmppv_pmu' callbacks and uses kvmppc_update_l0_stats() to update
'l0_stats' and the update the 'struct perf_event's event-counter.
Some minor updates to kvmppc_pmu_{add, del, read}() to remove some debug
scaffolding code.
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250416162740.93143-7-vaibhav@linux.ibm.com
Implement and setup necessary structures to send a prepolulated
Guest-State-Buffer(GSB) requesting hostwide counters to L0-PowerVM and have
the returned GSB holding the values of these counters parsed. This is done
via existing GSB implementation and with the newly added support of
Hostwide elements in GSB.
The request to L0-PowerVM to return Hostwide counters is done using a
pre-allocated GSB named 'gsb_l0_stats'. To be able to populate this GSB
with the needed Guest-State-Elements (GSIDs) a instance of 'struct
kvmppc_gs_msg' named 'gsm_l0_stats' is introduced. The 'gsm_l0_stats' is
tied to an instance of 'struct kvmppc_gs_msg_ops' named 'gsb_ops_l0_stats'
which holds various callbacks to be compute the size ( hostwide_get_size()
), populate the GSB ( hostwide_fill_info() ) and
refresh ( hostwide_refresh_info() ) the contents of
'l0_stats' that holds the Hostwide counters returned from L0-PowerVM.
To protect these structures from simultaneous access a spinlock
'lock_l0_stats' has been introduced. The allocation and initialization of
the above structures is done in newly introduced kvmppc_init_hostwide() and
similarly the cleanup is performed in newly introduced
kvmppc_cleanup_hostwide().
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250416162740.93143-6-vaibhav@linux.ibm.com
Introduce a new PMU named 'kvm-hv' inside a new module named 'kvm-hv-pmu'
to report Book3s kvm-hv specific performance counters. This will expose
KVM-HV specific performance attributes to user-space via kernel's PMU
infrastructure and would enableusers to monitor active kvm-hv based guests.
The patch creates necessary scaffolding to for the new PMU callbacks and
introduces the new kernel module name 'kvm-hv-pmu' which is built with
CONFIG_KVM_BOOK3S_HV_PMU. The patch doesn't introduce any perf-events yet,
which will be introduced in later patches
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250416162740.93143-5-vaibhav@linux.ibm.com
This change alters the PowerPC and x86 driver implementations to record
the last sample period before the event is updated for the next period.
A common pattern in PMU driver implementations is to have a
"*_event_set_period" function which takes care of updating the various
period-related fields in a perf_event structure. In most cases, the
drivers choose to call this function after initializing a sample data
structure with perf_sample_data_init. The x86 and PowerPC drivers
deviate from this, choosing to update the period before initializing the
sample data. When using an event with an alternate sample period, this
causes an incorrect period to be written to the sample data that gets
reported to userspace.
Signed-off-by: Mark Barnett <mark.barnett@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250408171530.140858-2-mark.barnett@arm.com
Pull driver core updatesk from Greg KH:
"Here is the big set of driver core updates for 6.15-rc1. Lots of stuff
happened this development cycle, including:
- kernfs scaling changes to make it even faster thanks to rcu
- bin_attribute constify work in many subsystems
- faux bus minor tweaks for the rust bindings
- rust binding updates for driver core, pci, and platform busses,
making more functionaliy available to rust drivers. These are all
due to people actually trying to use the bindings that were in
6.14.
- make Rafael and Danilo full co-maintainers of the driver core
codebase
- other minor fixes and updates"
* tag 'driver-core-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (52 commits)
rust: platform: require Send for Driver trait implementers
rust: pci: require Send for Driver trait implementers
rust: platform: impl Send + Sync for platform::Device
rust: pci: impl Send + Sync for pci::Device
rust: platform: fix unrestricted &mut platform::Device
rust: pci: fix unrestricted &mut pci::Device
rust: device: implement device context marker
rust: pci: use to_result() in enable_device_mem()
MAINTAINERS: driver core: mark Rafael and Danilo as co-maintainers
rust/kernel/faux: mark Registration methods inline
driver core: faux: only create the device if probe() succeeds
rust/faux: Add missing parent argument to Registration::new()
rust/faux: Drop #[repr(transparent)] from faux::Registration
rust: io: fix devres test with new io accessor functions
rust: io: rename `io::Io` accessors
kernfs: Move dput() outside of the RCU section.
efi: rci2: mark bin_attribute as __ro_after_init
rapidio: constify 'struct bin_attribute'
firmware: qemu_fw_cfg: constify 'struct bin_attribute'
powerpc/perf/hv-24x7: Constify 'struct bin_attribute'
...
Pull powerpc updates from Madhavan Srinivasan:
- Remove support for IBM Cell Blades
- SMP support for microwatt platform
- Support for inline static calls on PPC32
- Enable pmu selftests for power11 platform
- Enable hardware trace macro (HTM) hcall support
- Support for limited address mode capability
- Changes to RMA size from 512 MB to 768 MB to handle fadump
- Misc fixes and cleanups
Thanks to Abhishek Dubey, Amit Machhiwal, Andreas Schwab, Arnd Bergmann,
Athira Rajeev, Avnish Chouhan, Christophe Leroy, Disha Goel, Donet Tom,
Gaurav Batra, Gautam Menghani, Hari Bathini, Kajol Jain, Kees Cook,
Mahesh Salgaonkar, Michael Ellerman, Paul Mackerras, Ritesh Harjani
(IBM), Sathvika Vasireddy, Segher Boessenkool, Sourabh Jain, Vaibhav
Jain, and Venkat Rao Bagalkote.
* tag 'powerpc-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (61 commits)
powerpc/kexec: fix physical address calculation in clear_utlb_entry()
crypto: powerpc: Mark ghashp8-ppc.o as an OBJECT_FILES_NON_STANDARD
powerpc: Fix 'intra_function_call not a direct call' warning
powerpc/perf: Fix ref-counting on the PMU 'vpa_pmu'
KVM: PPC: Enable CAP_SPAPR_TCE_VFIO on pSeries KVM guests
powerpc/prom_init: Fixup missing #size-cells on PowerBook6,7
powerpc/microwatt: Add SMP support
powerpc: Define config option for processors with broadcast TLBIE
powerpc/microwatt: Define an idle power-save function
powerpc/microwatt: Device-tree updates
powerpc/microwatt: Select COMMON_CLK in order to get the clock framework
net: toshiba: Remove reference to PPC_IBM_CELL_BLADE
net: spider_net: Remove powerpc Cell driver
cpufreq: ppc_cbe: Remove powerpc Cell driver
genirq: Remove IRQ_EDGE_EOI_HANDLER
docs: Remove reference to removed CBE_CPUFREQ_SPU_GOVERNOR
powerpc: Remove UDBG_RTAS_CONSOLE
powerpc/io: Use standard barrier macros in io.c
powerpc/io: Rename _insw_ns() etc.
powerpc/io: Use generic raw accessors
...
To save/restore LBR call stack data in system-wide mode, the task_struct
information is required.
Extend the parameters of sched_task() to supply task_struct information.
When schedule in, the LBR call stack data for new task will be restored.
When schedule out, the LBR call stack data for old task will be saved.
Only need to pass the required task_struct information.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250314172700.438923-4-kan.liang@linux.intel.com
Commit 176cda0619 ("powerpc/perf: Add perf interface to expose vpa
counters") introduced 'vpa_pmu' to expose Book3s-HV nested APIv2 provided
L1<->L2 context switch latency counters to L1 user-space via
perf-events. However the newly introduced PMU named 'vpa_pmu' doesn't
assign ownership of the PMU to the module 'vpa_pmu'. Consequently the
module 'vpa_pmu' can be unloaded while one of the perf-events are still
active, which can lead to kernel oops and panic of the form below on a
Pseries-LPAR:
BUG: Kernel NULL pointer dereference on read at 0x00000058
<snip>
NIP [c000000000506cb8] event_sched_out+0x40/0x258
LR [c00000000050e8a4] __perf_remove_from_context+0x7c/0x2b0
Call Trace:
[c00000025fc3fc30] [c00000025f8457a8] 0xc00000025f8457a8 (unreliable)
[c00000025fc3fc80] [fffffffffffffee0] 0xfffffffffffffee0
[c00000025fc3fcd0] [c000000000501e70] event_function+0xa8/0x120
<snip>
Kernel panic - not syncing: Aiee, killing interrupt handler!
Fix this by adding the module ownership to 'vpa_pmu' so that the module
'vpa_pmu' is ref-counted and prevented from being unloaded when perf-events
are initialized.
Fixes: 176cda0619 ("powerpc/perf: Add perf interface to expose vpa counters")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250204153527.125491-1-vaibhav@linux.ibm.com
