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2026-07-31Merge back cpufreq material for 7.3Rafael J. Wysocki1-3/+5
* pm-cpufreq: cpufreq/amd-pstate: handle missing policy in dynamic EPP callbacks cpufreq/amd-pstate: Cache the firmware programmed EPP value cpufreq/amd-pstate: Toggle auto_sel in active mode on shared memory systems cpufreq/amd-pstate: Fix EPP return type and handle errors during initialization cpufreq: amd-pstate-ut: Skip tests when amd-pstate driver is not active cpufreq: schedutil: Replace sprintf() with sysfs_emit() in sysfs show cpufreq: schedutil: Fix self-contradictory comment in sugov_iowait_apply() Documentation: admin-guide: cpufreq: fix sampling_rate example command cpufreq: intel_pstate: Move two functions closer to callers cpufreq: intel_pstate: Consolidate frequency values computation cpufreq: intel_pstate: Introduce intel_pstate_update_freq_limits() cpufreq: intel_pstate: Fix setting minimum P-state at init time cpufreq: intel_pstate: Rename INTEL_PSTATE_HWP_BROADWELL cpufreq: intel_pstate: Simplify HWP handling on Broadwell cpufreq: intel_pstate: Adjust the .adjust_perf() driver callback cpufreq: intel_pstate: Rearrange checks in hybrid_get_cost()
2026-07-31rv: Use generic rv_this for the rv_monitor variable in LTLGabriele Monaco2-6/+6
Align the rv_monitor variable name in LTL to the generic rv_this as it is already done for DA/HA monitors. This improves consistency and eases assumptions across model classes. Reviewed-by: Nam Cao <namcao@linutronix.de> Link: https://lore.kernel.org/r/20260723074534.43521-2-gmonaco@redhat.com Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-31stop_machine: Make stop_one_cpu_nowait() return voidYury Norov1-8/+6
No caller checks the return value from stop_one_cpu_nowait(). All callers require the callback to run and arrange for the target CPU's stopper to remain enabled while queuing the work. In particular, commit f0498d2a54e7 ("sched: Fix stop_one_cpu_nowait() vs hotplug") added preemption protection to the scheduler callers so that queuing must succeed once the target CPU has been observed online. Therefore, a failure is an unrecoverable violation rather than a condition individual callers can recover from. Diagnose it with WARN_ON_ONCE() in stop_one_cpu_nowait(). A check in the common helper covers current and future callers consistently, while individual checks would duplicate the same non-recoverable handling at every call site. Make the function return void because there is no longer a meaningful result for callers to consume. On UP, warn if the supplied CPU is not the current CPU because the work cannot be scheduled in that case. Signed-off-by: Yury Norov <ynorov@nvidia.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Bradley Morgan <include@grrlz.net> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://patch.msgid.link/20260729022355.325058-1-ynorov@nvidia.com
2026-07-31Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar39-255/+675
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2026-07-31locking/percpu-rwsem: Annotate intentional data race in readers_active_check()Sun Shaojie1-1/+1
KCSAN reports a data race between readers_active_check() and a concurrently executing reader: BUG: KCSAN: data-race in readers_active_check / percpu_down_write race at unknown origin, with read to 0xffff9f3eb5bf5f30 of 4 bytes by task 1271 on cpu 14: readers_active_check+0x... percpu_down_write+0x152/0x1f0 value changed: 0xfffffff9 -> 0xfffffff8 readers_active_check() calls per_cpu_sum(*sem->read_count), which iterates over all CPUs and reads each CPU's per-CPU read_count variable. Concurrently, a reader on a remote CPU is modifying its own CPU's read_count via this_cpu_inc() / this_cpu_dec() as it enters and exits the critical section. These are plain reads and writes to the same per-CPU storage, hence KCSAN flags a data race. This race is benign. readers_active_check() is called from the percpu_down_write() wait loop (rcuwait_wait_event) after sem->block is already set. At this point: - New readers must immediately back out (they see block set, decrement their counter, and wake the writer), so counters can only decrease. - If the sum catches a reader's increment before its decrement, readers_active_check() sees a non-zero sum and returns false. The writer merely iterates the wait loop again -- a harmless retry. - A false zero (observing sum == 0 while a reader is still active) cannot happen: per_cpu_sum() reads each CPU's counter, and each per-CPU int read is atomic on all architectures, so an active reader's counter is always seen as non-zero. Annotate the read with data_race() to suppress the KCSAN warning and document the intentional nature of this unlocked access. Signed-off-by: Sun Shaojie <sunshaojie@kylinos.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260623104132.505117-1-sunshaojie@kylinos.cn
2026-07-31locking/lockdep: Fix NULL pointer dereference in __lock_set_class()Naveen Kumar Chaudhary1-0/+2
register_lock_class() can return NULL when the lock class pool is exhausted, graph_lock() fails, or key validation fails. However, __lock_set_class() uses the return value directly in pointer arithmetic without a NULL check: class = register_lock_class(lock, subclass, 0); hlock->class_idx = class - lock_classes; If class is NULL, this computes a wild offset that corrupts hlock->class_idx. The subsequent reacquire_held_locks() call will invoke hlock_class() with this corrupted index, leading to a NULL or out-of-bounds pointer dereference. Add the missing NULL check, consistent with how __lock_acquire() already handles this case at the same call site. Fixes: 64aa348edc61 ("lockdep: lock_set_subclass - reset a held lock's subclass") Signed-off-by: Naveen Kumar Chaudhary <naveen.osdev@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Waiman Long <longman@redhat.com> Reviewed-by: Dmitry Ilvokhin <d@ilvokhin.com> Link: https://patch.msgid.link/h2kfw43n4527x6mgi2lwpz2rieqnfzgictpv4wr5nyfjkc47co@2r5vz4uz44db
2026-07-31uprobes: Fix NULL pointer dereference in hprobe_expire()Breno Leitao1-1/+1
Forking a task that has a pending uretprobe can oops the kernel with a NULL pointer dereference in the clone() path: BUG: kernel NULL pointer dereference, address: 0000000000000018 Oops: 0002 [#1] SMP NOPTI RIP: 0010:hprobe_expire CR2: 0000000000000018 Call Trace: uprobe_copy_process copy_process kernel_clone __x64_sys_clone do_syscall_64 entry_SYSCALL_64_after_hwframe This was found on real hosts on Meta fleet. I've got the impression that this is what is happening: CPU 1 CPU 2 (traced task) ----- ------------------- hit uprobe, prepare_uretprobe(): hprobe LEASED, refcount >= 1 uprobe_unregister() put_uprobe(): refcount -> 0 fork() -> dup_utask() hprobe_expire(hprobe, true) try_get_uprobe() -> NULL get_uprobe(NULL) <-- Oops Only take the extra reference when the uprobe is non-NULL; a NULL means it is gone and is the correct value to return. Fixes: dd1a7567784e ("uprobes: SRCU-protect uretprobe lifetime (with timeout)") Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260729-uprobe-v1-1-61896b87c867@debian.org
2026-07-31swiotlb: remove unused SWIOTLB_FORCE flagAneesh Kumar K.V (Arm)1-2/+1
SWIOTLB_FORCE has no remaining in-tree users. Forced bouncing is now controlled through the swiotlb=force command line option via swiotlb_force_bounce. Remove the unused flag and simplify the force_bounce initialization. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-24-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: swiotlb: handle set_memory_decrypted() failuresAneesh Kumar K.V (Arm)1-15/+65
Check the return value when converting swiotlb pools between encrypted and decrypted mappings. If the default pool cannot be decrypted after early initialization, mark the pool fully used so it cannot satisfy future bounce allocations. For late initialization, return the `set_memory_decrypted()` failure. For restricted DMA pools, fail device initialization if the reserved pool cannot be decrypted. This prevents swiotlb from using pools whose encryption attributes do not match their metadata, and avoids returning pages with uncertain encryption state back to the allocator. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-23-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: swiotlb: free dynamic pools from process contextAneesh Kumar K.V (Arm)1-8/+11
swiotlb_dyn_free() is used after removing a dynamic swiotlb pool from RCU-protected lists. It can call swiotlb_free_tlb(), which may need to restore the encryption state of an unencrypted pool with set_memory_encrypted() before freeing the pages. RCU callbacks run in atomic context, but set_memory_encrypted() is not guaranteed to be atomic-safe on all architectures. For example, page attribute updates may allocate page tables or take sleeping locks. Use queue_rcu_work() for dynamic pool freeing instead. This keeps the RCU grace period before freeing a published pool, while running the actual pool teardown from workqueue context. Use the same helper for the transient-pool error path, since that path may also be reached from atomic DMA mapping context. Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-22-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: rename ret to cpu_addr in alloc helpersAneesh Kumar K.V (Arm)1-20/+20
ret in dma_direct_alloc() and dma_direct_alloc_pages() holds the returned CPU mapping, not a generic return value. Rename it to cpu_addr and update the remaining uses to match. This makes the allocation paths easier to follow and keeps the local naming consistent with what the variable actually represents. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-21-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHAREDAneesh Kumar K.V (Arm)1-17/+26
Make the dma-direct helpers derive the DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED instead of implicitly relying on force_dma_unencrypted() inside phys_to_dma_direct() Pass an explicit unencrypted/decrypted state into phys_to_dma_direct(), make the alloc paths return DMA addresses that match the requested buffer encryption state. Also only call dma_set_decrypted() when __DMA_ATTR_ALLOC_CC_SHARED is actually set. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-20-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: set decrypted flag for remapped DMA allocationsAneesh Kumar K.V (Arm)1-12/+44
Devices that are DMA non-coherent and require a remap were skipping dma_set_decrypted(), leaving DMA buffers encrypted even when the device requires unencrypted access. Move the call after the if (remap) branch so that both the direct and remapped allocation paths correctly mark the allocation as decrypted (or fail cleanly) before use. Fix dma_direct_alloc() and dma_direct_free() to apply set_memory_*() to the linear-map alias of the backing pages instead of the remapped CPU address. Also disallow highmem pages for __DMA_ATTR_ALLOC_CC_SHARED, because highmem buffers do not provide a usable linear-map address. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-19-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHAREDAneesh Kumar K.V (Arm)1-22/+30
Teach dma_direct_map_phys() to select the DMA address encoding based on DMA_ATTR_CC_SHARED. Use phys_to_dma_unencrypted() for decrypted mappings and phys_to_dma_encrypted() otherwise. If a device requires unencrypted DMA but the source physical address is still encrypted, force the mapping through swiotlb so the DMA address and backing memory attributes remain consistent. Update the arm64, x86, s390 and powerpc secure-guest setup to not use swiotlb force option Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-18-aneesh.kumar@kernel.org [mszyprow: rebased onto latest changes in arch/arm64/mm/init.c] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: Move dma_direct_map_phys() to dma/direct.cAneesh Kumar K.V (Arm)2-53/+56
dma_direct_map_phys() is too large to benefit from being inlined. Move its implementation to direct.c and leave the declaration in direct.h. No functional change in this patch Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-17-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: pass attrs to dma_capable() for DMA_ATTR_CC_SHARED checksAneesh Kumar K.V (Arm)2-4/+4
Teach dma_capable() about DMA_ATTR_CC_SHARED so the capability check can reject encrypted DMA addresses for devices that require unencrypted/shared DMA. Also propagate DMA_ATTR_CC_SHARED in swiotlb_map() when the selected SWIOTLB pool is decrypted so the capability check sees the correct DMA address attribute. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-16-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-mapping: make dma_pgprot() honor __DMA_ATTR_ALLOC_CC_SHAREDAneesh Kumar K.V (Arm)2-9/+15
Fold encrypted/decrypted pgprot selection into dma_pgprot() so callers do not need to adjust the page protection separately. Update dma_pgprot() to apply pgprot_decrypted() when DMA_ATTR_CC_SHARED or __DMA_ATTR_ALLOC_CC_SHARED is set and pgprot_encrypted() otherwise Convert the dma-direct mmap paths to pass DMA_ATTR_CC_SHARED instead of open-coding force_dma_unencrypted() handling around dma_pgprot(). Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-15-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHAREDAneesh Kumar K.V (Arm)2-46/+144
Teach swiotlb to distinguish between encrypted and decrypted bounce buffer pools, and make allocation and mapping paths select a pool whose state matches the requested DMA attributes. Add a cc_shared flag to io_tlb_mem, initialize it for the default and restricted pools, and propagate __DMA_ATTR_ALLOC_CC_SHARED into swiotlb pool allocation. Reject swiotlb alloc/map requests when the selected pool does not match the required encrypted/decrypted state. Also return DMA addresses with the matching phys_to_dma_{encrypted, unencrypted} helper so the DMA address encoding stays consistent with the chosen pool. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-14-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: swiotlb: pass mapping attributes by referenceAneesh Kumar K.V (Arm)1-3/+3
Change swiotlb_tbl_map_single() to take the DMA mapping attributes by reference and update the direct callers accordingly. This is a preparatory change for a follow-up patch which updates the attributes based on the selected swiotlb pool. Keeping the signature change separate makes the follow-up patch easier to review. No functional change in this patch. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-13-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-pool: track decrypted atomic pools and select them via attrsAneesh Kumar K.V (Arm)3-72/+132
Teach the atomic DMA pool code to distinguish between encrypted and unencrypted pools, and make pool allocation select the matching pool based on DMA attributes. Introduce a dma_gen_pool wrapper that records whether a pool is unencrypted, initialize that state when the atomic pools are created, and use it when expanding and resizing the pools. Update dma_alloc_from_pool() to take attrs and skip pools whose encrypted state does not match __DMA_ATTR_ALLOC_CC_SHARED. Update dma_free_from_pool() accordingly. Also pass __DMA_ATTR_ALLOC_CC_SHARED from the swiotlb atomic allocation path so decrypted swiotlb allocations are taken from the correct atomic pool. Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-12-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free pathsAneesh Kumar K.V (Arm)2-9/+42
Propagate force_dma_unencrypted() into __DMA_ATTR_ALLOC_CC_SHARED in the dma-direct allocation path and use the attribute to drive the related decisions. This updates dma_direct_alloc(), dma_direct_free(), and dma_direct_alloc_pages() to fold the forced unencrypted case into attrs. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-11-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pagesAneesh Kumar K.V (Arm)2-18/+59
Move swiotlb allocation out of __dma_direct_alloc_pages() and handle it in dma_direct_alloc() / dma_direct_alloc_pages(). This is needed for follow-up changes that simplify the handling of memory encryption/decryption based on the DMA attribute flags. swiotlb backing pages are already mapped decrypted by swiotlb_update_mem_attributes() and rmem_swiotlb_device_init(), so dma-direct should not call dma_set_decrypted() on allocation nor dma_set_encrypted() on free for swiotlb-backed memory. Update alloc/free paths to detect swiotlb-backed pages and skip encrypt/decrypt transitions for those paths. Keep the existing highmem rejection in dma_direct_alloc_pages() for swiotlb allocations. Only for "restricted-dma-pool", we currently set `for_alloc = true`, while rmem_swiotlb_device_init() decrypts the whole pool up front. This pool is typically used together with "shared-dma-pool", where the shared region is accessed after remap/ioremap and the returned address is suitable for decrypted memory access. So existing code paths remain valid. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Jiri Pirko <jiri@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-8-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31swiotlb: Preserve allocation virtual address for dynamic poolsAneesh Kumar K.V (Arm)1-12/+19
swiotlb_alloc_tlb() can allocate from the DMA atomic pool when a decrypted pool is needed from atomic context. With CONFIG_DMA_DIRECT_REMAP, the atomic pool is backed by remapped virtual addresses, which are not the same as the direct-map addresses returned by phys_to_virt(). swiotlb_init_io_tlb_pool() currently reconstructs the pool virtual address from the physical start address. For atomic-pool backed allocations this stores the wrong address in pool->vaddr. Later, swiotlb_free_tlb() passes that address to dma_free_from_pool(), which will fail to recognize the chunk Pass the virtual address returned by the allocation path into swiotlb_init_io_tlb_pool(), and store that address in pool->vaddr. This keeps the pool free path using the same virtual address as the allocator. Fixes: 79636caad361 ("swiotlb: if swiotlb is full, fall back to a transient memory pool") Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-6-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma: free atomic pool pages by physical addressAneesh Kumar K.V (Arm)2-2/+63
dma_direct_alloc_pages() may satisfy atomic allocations from the coherent atomic pools. The pool allocation is keyed by the virtual address stored in the gen_pool, but the pages API returns only the backing struct page. On architectures with CONFIG_DMA_DIRECT_REMAP, atomic pool chunks are added to the gen_pool using their remapped virtual address. dma_direct_free_pages() reconstructs a linear-map address with page_address(page) and passes that to dma_free_from_pool(). That address does not match the gen_pool virtual range, so the pool lookup can fail and the code can fall through to freeing a pool-owned page through the normal page allocator path. Add a page-based pool free helper that looks up the owning pool chunk by physical address, translates it back to the gen_pool virtual address, and frees that address to the pool. Use it from dma_direct_free_pages() while keeping the existing virtual-address helper for coherent allocation frees. Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-5-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-pool: fix page leak in atomic_pool_expand() cleanupAneesh Kumar K.V (Arm)1-3/+7
atomic_pool_expand() frees the allocated pages from the remove_mapping error path only when CONFIG_DMA_DIRECT_REMAP is enabled. When CONFIG_DMA_DIRECT_REMAP is disabled, failures after page allocation, such as gen_pool_add_virt(), jump to remove_mapping and return without freeing the pages. Move __free_pages(page, order) out of the CONFIG_DMA_DIRECT_REMAP block so that cleanup paths always release the allocation. Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Link: https://lore.kernel.org/r/20260717180442.110954-3-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31dma-direct: return struct page from dma_direct_alloc_from_pool()Aneesh Kumar K.V (Arm)1-8/+10
Commit 5b138c534fda ("dma-direct: factor out a dma_direct_alloc_from_pool helper") changed dma_direct_alloc_from_pool() to return the CPU address from dma_alloc_from_pool(). That fits dma_direct_alloc(), but dma_direct_alloc_pages() also uses the helper and expects a struct page *. Fix this by making dma_direct_alloc_from_pool() return the struct page * again, and pass the CPU address back through an out-parameter for the dma_direct_alloc() caller. Fixes: 5b138c534fda ("dma-direct: factor out a dma_direct_alloc_from_pool helper") Cc: stable@vger.kernel.org Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org> Reviewed-by: Mostafa Saleh <smostafa@google.com> Link: https://lore.kernel.org/r/20260717180442.110954-2-aneesh.kumar@kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-30bpf: Log error code on trampoline unlink failureXu Xin2-7/+13
Replace silent WARN_ON_ONCE with WARN_ONCE that prints the actual error code from bpf_trampoline_unlink_prog(). This aids debugging of race conditions during link teardown, while keeping the warning rate limited to avoid log flooding. This will be very helpful for speeding up trouble-shooting of some crash UAF due to bpf_trampoline_unlink_prog failures. No change to unlink behavior. Signed-off-by: Xu Xin <xu.xin16@zte.com.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Acked-by: Leon Hwang <leon.hwang@linux.dev> Link: https://lore.kernel.org/bpf/20260729141159128mEJmS_aujBKr-cBu1p_UI@zte.com.cn
2026-07-30bpf: Fix potential UAF when reading bpf link infoPu Lehui1-4/+17
In bpf_link_show_fdinfo and bpf_link_get_info_by_fd, link->prog is accessed without holding any locks. If the prog is concurrently replaced via bpf_link_update, the old prog can be freed, leading to a potential UAF issue. Fix this by accessing link->prog under RCU protection to safely fetch the pointer and guarantee its lifetime while reading its fields. Fixes: 0c991ebc8c69 ("bpf: Implement bpf_prog replacement for an active bpf_cgroup_link") Reported-by: Sashiko <sashiko-bot@kernel.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Reviewed-by: Amery Hung <ameryhung@gmail.com> Acked-by: Leon Hwang <leon.hwang@linux.dev> Link: https://lore.kernel.org/bpf/f87b53c0-8f00-45a6-82db-8242fa9b143f@huaweicloud.com [0] Link: https://lore.kernel.org/bpf/20260728025457.2814876-1-pulehui@huaweicloud.com
2026-07-30bpf: Fix potential UAF in bpf_netns_link_update_progPu Lehui1-11/+6
In bpf_netns_link_update_prog, the checks for old_prog and prog type are currently performed locklessly before acquiring netns_bpf_mutex. This creates a race condition that can lead to a UAF issue. If two threads concurrently execute BPF_LINK_UPDATE on the same netns link, the following execution path can trigger a UAF: CPU0 CPU1 bpf_netns_link_update_prog if (old_prog && old_prog != link->prog) return -EPERM; bpf_netns_link_update_prog if (old_prog && old_prog != link->prog) ... old_prog = xchg(&link->prog, new_prog); bpf_prog_put(old_prog); if (new_prog->type != link->prog->type) <-- trigger UAF Fix this by moving the old_prog and prog->type checks inside the netns_bpf_mutex critical section. Meanwhile, use guard() to simplify lock management and avoid all the goto jumping. Fixes: 7f045a49fee0 ("bpf: Add link-based BPF program attachment to network namespace") Reported-by: Sashiko <sashiko-bot@kernel.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Amery Hung <ameryhung@gmail.com> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/f87b53c0-8f00-45a6-82db-8242fa9b143f@huaweicloud.com [0] Link: https://lore.kernel.org/bpf/20260728023259.2813482-1-pulehui@huaweicloud.com
2026-07-30Merge tag 'audit-pr-20260730' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/auditLinus Torvalds2-4/+13
Pull audit fixes from Paul Moore: - Fix potential integer overflows in audit_log_n_string() Similar to the earlier fix to audit_log_n_hex() that you merged earlier in July. Expect a cleaner, and generally better fix for these functions in an upcoming merge window, but this addresses the problem in a small patch that should be easy for people to backport. - Fix potential use-after-free in audit_del_rule() * tag 'audit-pr-20260730' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: fix potential use-after-free in audit_del_rule() audit: fix potential integer overflow in audit_log_n_string()
2026-07-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski14-23/+103
Cross-merge networking fixes after downstream PR (net-7.2-rc6). No conflicts. Adjacent changes: net/ipv4/route.c dbc3791e3b24 ("net: do not send ICMP/NDISC Redirects when peer allocation fails") 7804eaa057fe ("ipv4: snapshot dst.dev in ip_rt_send_redirect() and ip_rt_get_source()") drivers/net/tun.c 23dad2d088df ("tun: no longer rely on RTNL in tun_fill_info()") c3da92af07ea ("Revert "tun/tap: add ptr_ring consume helper with netdev queue wakeup"") drivers/net/ethernet/marvell/octeontx2/af/rvu_npc.c 3bd438a58e91 ("octeontx2-af: Block VFs from clobbering special CGX PKIND state") 5ba5611ef946 ("octeontx2-af: reserve 4 PKINDs for skip-size custom use") drivers/net/wireless/ath/ath12k/core.h drivers/net/wireless/ath/ath12k/mac.c drivers/net/wireless/ath/ath12k/peer.c 469d7e6077c1 ("wifi: ath12k: resolve PENDING ML peer ID from MLO_PEER_MAP HTT event") 378e659029d5 ("wifi: ath12k: introduce host_alloc_ml_id hardware parameter") c42b27336eef ("wifi: ath12k: fix survey indexing across bands") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-30Merge tag 'pm-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds1-0/+11
Pull power management fixes from Rafael Wysocki: "These fix issues related to cpufreq, in the ACPI CPPC library and the generic CPPC cpufreq driver, in the powernow-k8 and amd-pstate drivers, and in the schedutil governor: - Allow fast frequency switching in the ACPI CPPC library only when every supported control used by the driver callback has an address space already accepted for fast access (Christian Loehle) - Skip writes to unsupported performance controls in the ACPI CPPC library (Christian Loehle) - Update cppc_cpufreq_update_perf_limits() to read policy->min and policy->max once and, if the lockless snapshot is inconsistent, reduce the minimum to the observed maximum, along the lines of cpufreq_driver_resolve_freq() (Christian Loehle) - Fix a possible memory leak in the powernowk8_cpu_init() error paths (Abdun Nihaal) - Loosen the requirement on lowest nonlinear frequency != min freq in the amd-pstate driver that is too tight for new systems some of which actually have the lowest nonlinear frequency identical to the minimum frequency (Mario Limonciello) - Prevent amd-pstate from loading on unsupported hardware (Rong Zhang) - Address an initialization race in the schedutil governor when it runs on multi-CPU cpufreq policies, by making it initialize all per-CPU structures first and only then publish the per-CPU utilization update hooks (Zhongqiu Han)" * tag 'pm-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: powernow-k8: Fix possible memory leak in powernowk8_cpu_init() ACPI: CPPC: Skip writes to unsupported performance controls cpufreq/amd-pstate: Prevent the driver from loading on unsupported hardware cpufreq/amd-pstate: Loosen requirement on lowest nonlinear frequency != min freq cpufreq: schedutil: Publish util hooks only after all sg_cpu are initialized cpufreq: cppc: Sanitize lockless policy limit snapshots ACPI: CPPC: Check all controls for fast switching
2026-07-30rcu-tasks: Fix some comments for call_rcu_tasks() and call_rcu_tasks_rude()Zqiang1-4/+4
The comments for call_rcu_tasks() and call_rcu_tasks_rude() referred to "RCU read-side critical sections", which is ambiguous. specify "rcu-tasks" and "rcu-tasks rude" respectively to match the actual flavor being described. Signed-off-by: Zqiang <qiang.zhang@linux.dev> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30rcu-tasks: Rename tasks_rcu_exit_srcu_stall_timer to tasks_rcu_exit_stall_timerZqiang1-8/+8
This 'commit 1612160b9127 ("rcu-tasks: Eliminate deadlocks involving do_exit() and RCU tasks")' has reimplemented the rcu_tasks_postscan(), and the synchronize_srcu() has been removed, this commit therefore rename tasks_rcu_exit_srcu_stall_timer to tasks_rcu_exit_stall_timer. Signed-off-by: Zqiang <qiang.zhang@linux.dev> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30rcu: Mark interrupts-enabled accesses to rdp->cpu_no_qs.sPaul E. McKenney1-1/+1
The rdp->cpu_no_qs.s field is accessed only by the current CPU, but can be accessed both at task level and from interrupt handlers. All accesses from interrupts-enabled code must therefore be marked. This commit therefore converts from __this_cpu_read() to this_cpu_read(), but only in interrupts-enabled code, that is, the rcu_qs() function. KCSAN located this issue. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30rcu: Reduce stack usage in show_rcu_gp_kthreads()Zqiang1-18/+29
When CONFIG_KASAN=y and CONFIG_KASAN_STACK=y builds, the show_rcu_gp_kthreads() exceeds the 1024-byte frame-size limit: make kernel/rcu/tree.o KCFLAGS="-fstack-usage" DESCEND objtool DESCEND bpf/resolve_btfids INSTALL libsubcmd_headers CC kernel/rcu/tree.o In file included from kernel/rcu/tree.c:4998: kernel/rcu/tree_stall.h: In function 'show_rcu_gp_kthreads': kernel/rcu/tree_stall.h:994:1: warning: the frame size of 1656 bytes is larger than 1024 bytes [-Wframe-larger-than=] grep show_rcu kernel/rcu/tree.su tree_nocb.h:1622:13:show_rcu_nocb_state 896 dynamic,bounded tree_stall.h:933:6:show_rcu_gp_kthreads 1784 dynamic,bounded tree_stall.h:1102:13:sysrq_show_rcu 16 static Wrap the pr_info() into two noinline_for_stack helpers function: show_rcu_state() print rcu_state status, and show_rcu_node() print single rcu_node status. After apply this change: grep show_rcu kernel/rcu/tree.su tree_stall.h:955:22:show_rcu_node 696 dynamic,bounded tree_stall.h:930:22:show_rcu_state 872 dynamic,bounded tree_nocb.h:1622:13:show_rcu_nocb_state 896 dynamic,bounded tree_stall.h:972:6:show_rcu_gp_kthreads 544 static tree_stall.h:1113:13:sysrq_show_rcu 16 static Signed-off-by: Zqiang <qiang.zhang@linux.dev> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30rcu: Mark accesses to ->rcu_urgent_qs and ->rcu_need_heavy_qsItai Handler1-5/+5
rcu_all_qs() and rcu_note_context_switch() read/clear the per-CPU ->rcu_urgent_qs and ->rcu_need_heavy_qs flags with plain raw_cpu_read() and this_cpu_write(), while the RCU core clears them with WRITE_ONCE() in rcu_disable_urgency_upon_qs(). KCSAN flags the resulting same-CPU race: BUG: KCSAN: data-race in rcu_all_qs / rcu_disable_urgency_upon_qs It is benign -- the flags are advisory and rcu_all_qs() re-reads ->rcu_urgent_qs with smp_load_acquire() before acting on it -- but these are the last unmarked accesses to the two flags; every other access already uses READ_ONCE()/WRITE_ONCE()/smp_*. Mark them to match. No functional change. Reproduced on a PREEMPT_NONE, CONFIG_KCSAN_INTERRUPT_WATCHER=y kernel with a pthreads program whose threads (two per CPU) loop reading a large file: for (;;) { int fd = open("/proc/kallsyms", O_RDONLY); while (read(fd, buf, sizeof(buf)) > 0) ; close(fd); } The read()s drive cond_resched() -> rcu_all_qs() while the busy CPUs keep the grace period urgent, so the RCU core clears the flags concurrently. Fixes: 2dba13f0b6c2 ("rcu: Switch urgent quiescent-state requests to rcu_data structure") Signed-off-by: Itai Handler <itai.handler@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30rcu: Remove unused rdp parameter from rcu_check_gp_start_stall()Zqiang3-6/+4
The rcu_check_gp_start_stall() works entirely on rnp parameter, and never uses it's rdp parameter. this commit therefore drop it, updating both callers and the declaration. No functional change. Signed-off-by: Zqiang <qiang.zhang@linux.dev> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30rcu: Mark interrupts-enabled accesses to rdp->cpu_no_qs.b.normPaul E. McKenney2-5/+5
The rdp->cpu_no_qs.b.norm field is accessed only by the current CPU, but can be accessed both at task level and from interrupt handlers. All accesses from interrupts-enabled code must therefore be marked. This commit therefore converts from __this_cpu_read() to this_cpu_read(), from __this_cpu_write() to this_cpu_write(), and plain C-language accesses to READ_ONCE() and WRITE_ONCE(), but only in interrupts-enabled code. KCSAN located this issue. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2026-07-30sched/deadline: Use revised wakeup rule only for running dl_serverGabriele Monaco1-1/+2
Commit 14a857056466 ("sched/deadline: Use revised wakeup rule for dl_server") applies the revised wakeup rule to any server, as a result servers that are not running (dl_defer_running == 0) and start with a deadline overflow get enqueued and can boost tasks as if they were running, invalidating the defer rule and the documented state model. Apply the revised wakeup rule only for deferrable servers that are marked as running. Fixes: 14a857056466 ("sched/deadline: Use revised wakeup rule for dl_server") Signed-off-by: Gabriele Monaco <gmonaco@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juri Lelli <juri.lelli@redhat.com> Tested-by: Andrea Righi <arighi@nvidia.com> Link: https://patch.msgid.link/20260522125833.264145-1-gmonaco@redhat.com
2026-07-29ring-buffer: Fix reader page read offset for remote buffersVincent Donnefort1-0/+1
A page swapped in by __rb_get_reader_page_from_remote() retains its stale read offset, causing subsequent reads to skip events or read past valid data. Fix it. Link: https://patch.msgid.link/20260729133609.4022734-1-vdonnefort@google.com Fixes: fbd1743ecba1 ("ring-buffer: Add non-consuming read for ring-buffer remotes") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Reviewed-by: Keir Fraser <keirf@google.com> Tested-by: Keir Fraser <keirf@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-07-29audit: fix potential use-after-free in audit_del_rule()Luxiao Xu1-2/+4
`audit_del_rule()` destroys `e->rule.exe` via `audit_remove_mark_rule()` before unlinking the rule from RCU-visible filter lists and waiting for a grace period. Concurrent readers in `audit_filter()` and `audit_filter_rules()` still dereference `e->rule.exe`, while the fsnotify mark can be freed on an independent lifetime path. This creates a use-after-free window during rule deletion. Fix this by unlinking the rule from the RCU-visible lists and invoking `synchronize_rcu()` before calling `audit_remove_mark_rule()` (and other rule removal helpers). This ensures that all existing RCU readers have exited the critical section before any underlying resources are destroyed. Cc: stable@vger.kernel.org Fixes: 34d99af52ad4 ("audit: implement audit by executable") Reported-by: Vega <vega@nebusec.ai> Assisted-by: Codex:gpt-5.4 Signed-off-by: Luxiao Xu <rakukuip@gmail.com> Signed-off-by: Ren Wei <enjou1224z@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-07-29audit: fix potential integer overflow in audit_log_n_string()Zhan Xusheng1-2/+9
audit_log_n_string() computes new_len as "slen + 3" (enclosing quotes plus the NUL terminator) and stores it into an int, while slen is a size_t. For a sufficiently large slen the addition can overflow and/or the result be truncated when assigned to the int new_len, so the "new_len > avail" check can be bypassed and the subsequent memcpy(ptr, string, slen) can write past the skb tail. This is the same class of bug that was fixed for the hex sibling in commit 65dfde57d1e2 ("audit: fix potential integer overflow in audit_log_n_hex()"); both helpers are reached through audit_log_n_untrustedstring() with the same length source. Make new_len a size_t and use check_add_overflow() to catch the overflow, mirroring the audit_log_n_hex() fix. No functional change for the in-tree callers, which all pass bounded lengths. Cc: stable@vger.kernel.org Fixes: 168b7173959f ("AUDIT: Clean up logging of untrusted strings") Signed-off-by: Zhan Xusheng <zhanxusheng@xiaomi.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-07-29tracing/filters: Fix false positive match in regex_match_full()Masami Hiramatsu (Google)1-0/+3
regex_match_full() calls strncmp(str, r->pattern, len) where len is the target field buffer size. When len is smaller than r->len (the filter pattern length), strncmp() checks only len bytes of r->pattern against str. If those len bytes match, strncmp() returns 0, resulting in a false-positive match where a shorter string in a fixed-size field matches a longer filter pattern. For example, a 4-byte static string field containing "abcd" matched the filter pattern "abcdefgh" because strncmp("abcd", "abcdefgh", 4) returned 0. In this case, @len does NOT include '\0' because it is fixed-size array. Fix this by returning 0 (no match) early when len < r->len. Fixes: 1889d20922d1 ("tracing/filters: Provide basic regex support") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/178528488779.124250.5571741156199253769.stgit@devnote2 Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-07-29tracing: Check return value of __register_event() in trace_module_add_events()Masami Hiramatsu (Google)1-2/+2
trace_module_add_events() ignores the return value of __register_event() and unconditionally calls __add_event_to_tracers() for each event. If __register_event() fails (for example, if event_init() fails), the trace_event_call is not added to ftrace_events list, but __add_event_to_tracers() still creates a trace_event_file pointing to it. If module loading subsequently fails and module memory is freed, tracing state retains a stale trace_event_call pointer in trace_event_file, leading to a use-after-free when tracefs or tracing subsystem operations are later executed. Fix this by checking the return value of __register_event() and only calling __add_event_to_tracers() if event registration succeeded. Fixes: ae63b31e4d0e ("tracing: Separate out trace events from global variables") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/178528487878.124250.14170824576025743236.stgit@devnote2 Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-07-29tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functionsMasami Hiramatsu (Google)1-2/+10
mmio_trace_rw() and mmio_trace_mapping() retrieve mmio_trace_array into tr and pass it to __trace_mmiotrace_rw() and __trace_mmiotrace_map(). If these functions are invoked while mmio_trace_array is NULL (e.g. before initialization or after disabled), accessing tr->array_buffer.buffer will result in a NULL pointer dereference crash. Fix this by adding an explicit NULL check for tr at the beginning of __trace_mmiotrace_rw() and __trace_mmiotrace_map(). Link: https://patch.msgid.link/178524300062.56416.8362487250709962380.stgit@devnote2 Fixes: f984b51e0779 ("ftrace: add mmiotrace plugin") Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-07-29tracing/mmiotrace: Reset dropped_count in mmio_reset_data()Masami Hiramatsu (Google)1-0/+1
mmio_reset_data() is called during tracer initialization, reset, and start. While it resets overrun_detected and prev_overruns, it neglects to reset dropped_count. Consequently, dropped event counts from prior tracing sessions persist in dropped_count and corrupt overrun reports in subsequent runs. Fix this by explicitly calling atomic_set(&dropped_count, 0) in mmio_reset_data(). Link: https://patch.msgid.link/178524299122.56416.16277704230639425172.stgit@devnote2 Fixes: 173ed24ee2d6 ("mmiotrace: count events lost due to not recording") Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-07-29fprobe: Fix module reference count leak on error in register_fprobe()Masami Hiramatsu (Google)1-4/+2
In register_fprobe(), get_ips_from_filter() resolves target function addresses and increments module reference counts via try_module_get() for symbols in kernel modules. If get_ips_from_filter() fails on the second pass and returns an error, register_fprobe() returned directly without releasing module references acquired up to that point. Fix this by ensuring the cleanup loop executing module_put() runs even when get_ips_from_filter() returns a negative error. Link: https://lore.kernel.org/all/178528125360.101985.4144133640239273153.stgit@devnote2/ Fixes: d24fa977eec5 ("tracing: fprobe: Fix to lock module while registering fprobe") Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-29futex: Optimise the size check get_futex_key()Sebastian Andrzej Siewior1-1/+1
The futex address must be naturally aligned and this is checked via "address % size" where `address' is the supplied address and `size' is the expected size of futex. It is guaranteed that `size' is power of two but the compiler does not see it and creates here a `div' operation (x86, arm, gcc-15). We can take advantage of the pow2 property and rewrite it as "address & (size-1)". As per testing, the command |perf bench futex hash -f 1 -b 16384 -t 1 -r 30 improved from | [thread 0] futex: 0x5619f931f740 [ 7001583 ops/sec ] to | [thread 0] futex: 0x55da173e5740 [ 7376137 ops/sec ] or by 5.3% Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260701161736.xYYizA0e@linutronix.de
2026-07-29futex: Use runtime constants for __futex_hash() hot pathPeter Zijlstra1-19/+25
Runtime constify the read-only after init data __futex_shift(shift_32), __futex_mask(mask_32), and __futex_queues(ptr) used in __futex_hash() hot path to avoid referencing global variable. This also allows __futex_queues to be allocated dynamically to "nr_node_ids" slots instead of reserving config dependent MAX_NUMNODES (1 << CONFIG_NODES_SHIFT) worth of slots upfront. Runtime constants are initialized before their first access and runtime_const_init() provides necessary barrier to ensure subsequent accesses are not reordered against their initialization. No functional changes intended. perf bench futex on a 3rd Gen EPYC (2 x 64C/128T): +----------------+-----------+-----------+-----------+--------------+ | Benchmark | Kernel 1 | Kernel 2 | Unit | % Improvement| | | (avg/5) | (avg/5) | | (K2 vs K1) | +----------------+-----------+-----------+-----------+--------------+ | Wake-parallel | 0.01614 | 0.00456 | ms | +71.75% | | Requeue | 0.26394 | 0.24644 | ms | +6.63% | | Lock-pi | 34.0 | 57.2 | ops/sec | +68.24% | +----------------+-----------+-----------+-----------+--------------+ Performance testing on a 144-thread Intel(R) Xeon(R) CPU E7-8890 v3 (4 NUMA nodes): +-------------------------------------------------------------+ | perf bench futex hash -b 0 | +----------------------+------------+------------+------------+ | Configuration | As-is | Patched | Delta | +----------------------+------------+------------+------------+ | 1 thread, 1 futex | 6,449,632 | 6,532,004 | +1.28% | | 144 threads, 1024 fx | 2,111,486 | 2,139,685 | +1.34% | +----------------------+------------+------------+------------+i [ prateek: Dynamically allocate __futex_queues, mark the global data __ro_after_init since they are constified after futex_init(). ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> # MAX_NUMNODES bloat Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Charlie Jenkins <thecharlesjenkins@gmail.com> Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com> Link: https://patch.msgid.link/20260227161841.GH606826@noisy.programming.kicks-ass.net Link: https://patch.msgid.link/20260728052540.4728-9-kprateek.nayak@amd.com