kernel/linux.git/arch/arm, branch v7.1-rc5

Merge tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2026-05-21T21:05:09+00:00

Pull ring-buffer fixes from Steven Rostedt: - Fix reporting MISSED EVENTS in trace iterator When the "trace" file is read with tracing enabled, if the writer were to pass the iterator reader, it resets, sets a "missed_events" flag and continues. The tracing output checks for missed events and if there are some, it prints out "[LOST EVENTS]" to let the user know events were dropped. But the clearing of the missed_events happened when the tracing system queried the ring buffer iterator about missed events. This was premature as the ring buffer is per CPU, and the tracing code reads all the CPU buffers and checks for missed events when it is read. If the CPU iterator that had missed events isn't printed next, the output for the LOST EVENTS is lost. Clear the missed_events flag when the iterator moves to the next event and not when the missed_events flag is queried. Also clear it on reset. - Flush and stop the persistent ring buffer on panic On panic the persistent ring buffer is used to debug what caused the panic. But on some architectures, it requires flushing the memory from cache, otherwise, the ring buffer persistent memory may not have the last events and this could also cause the ring buffer to be corrupted on the next boot. - Fix nr_subbufs initialization in simple_ring_buffer_init_mm The remote simple ring buffer meta data nr_subbufs is initialized too early and gets cleared later on, making it zero and not reflect the actual number of sub-buffers. - Fix unload_page for simple_ring_buffer init rollback On error, the pages loaded need to be unloaded. To unload a page it is expected that: page = load_page(va); -> unload_page(page). But the code was doing: unload_page(va) and not unload_page(page). - Create output file from cmd_check_undefined The check for undefined symbols checks if the file *.o.checked exists and if so it skips doing the work. But the *.o.checked file never was created making every build do the work even when it was already done previously. * tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Create output file from cmd_check_undefined tracing: Fix unload_page for simple_ring_buffer init rollback tracing: Fix nr_subbufs initialization in simple_ring_buffer_init_mm() ring-buffer: Flush and stop persistent ring buffer on panic ring-buffer: Fix reporting of missed events in iterator

ring-buffer: Flush and stop persistent ring buffer on panic

2026-05-21T12:20:58+00:00

On real hardware, panic and machine reboot may not flush hardware cache to memory. This means the persistent ring buffer, which relies on a coherent state of memory, may not have its events written to the buffer and they may be lost. Moreover, there may be inconsistency with the counters which are used for validation of the integrity of the persistent ring buffer which may cause all data to be discarded. To avoid this issue, stop recording of the ring buffer on panic and flush the cache of the ring buffer's memory. Fixes: e645535a954a ("tracing: Add option to use memmapped memory for trace boot instance") Cc: stable@vger.kernel.org Cc: Will Deacon Cc: Mathieu Desnoyers Cc: Ian Rogers Link: https://patch.msgid.link/177751969602.2136606.12031934362587643488.stgit@mhiramat.tok.corp.google.com Signed-off-by: Masami Hiramatsu (Google) Acked-by: Catalin Marinas Acked-by: Geert Uytterhoeven Signed-off-by: Steven Rostedt

ARM: integrator: Fix early initialization

2026-05-07T12:03:21+00:00

Starting with commit bdb249fce9ad4 ("ARM: integrator: read counter using syscon/regmap"), intcp_init_early calls syscon_regmap_lookup_by_compatible which in turn calls of_syscon_register. This function allocates memory. Since the memory management code has not been initialized at that time, the call always fails. It either returns -ENOMEM or crashes as follows. Unable to handle kernel NULL pointer dereference at virtual address 0000000c when read [0000000c] *pgd=00000000 Internal error: Oops: 5 [#1] ARM Modules linked in: CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.15.0-rc5-00026-g5fcc9bf84ee5 #1 PREEMPT Hardware name: ARM Integrator/CP (Device Tree) PC is at __kmalloc_cache_noprof+0xec/0x39c LR is at __kmalloc_cache_noprof+0x34/0x39c ... Call trace: __kmalloc_cache_noprof from of_syscon_register+0x7c/0x310 of_syscon_register from device_node_get_regmap+0xa4/0xb0 device_node_get_regmap from intcp_init_early+0xc/0x40 intcp_init_early from start_kernel+0x60/0x688 start_kernel from 0x0 The crash is seen due to a dereferenced pointer which is not supposed to be NULL but is NULL if the memory management subsystem has not been initialized. The crash is not seen with all versions of gcc. Some versions such as gcc 9.x apparently do not dereference the pointer, presumably if tracing is disabled. The problem has been reproduced with gcc 10.x, 11.x, and 13.x. Either case, if the crash is not seen, the call to syscon_regmap_lookup_by_compatible returns -ENOMEM, and sched_clock_register is never called. Fix the problem by moving the early initialization code into the standard machine initialization code. Fixes: bdb249fce9ad4 ("ARM: integrator: read counter using syscon/regmap") Cc: Linus Walleij Signed-off-by: Guenter Roeck Link: https://lore.kernel.org/20250518164118.3859567-1-linux@roeck-us.net Signed-off-by: Linus Walleij Link: https://lore.kernel.org/r/20260505-integrator-fixes-v1-1-56ab9aac59db@kernel.org Signed-off-by: Arnd Bergmann

ARM: dts: renesas: rskrza1: Drop superfluous cells

2026-04-27T09:14:30+00:00

Drop superfluous address-cells and size-cells to fix DTC W=1 warning: arch/arm/boot/dts/renesas/r7s72100-rskrza1.dts:32.17-72.4: Warning (avoid_unnecessary_addr_size): /flash@18000000: unnecessary #address-cells/#size-cells without "ranges", "dma-ranges" or child "reg" or "ranges" property Signed-off-by: Marek Vasut Fixes: 98537eb77d3ef185 ("ARM: dts: renesas: rskrza1: Add FLASH nodes") Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260327234244.91707-7-marek.vasut+renesas@mailbox.org Signed-off-by: Geert Uytterhoeven

ARM: dts: renesas: genmai: Drop superfluous cells

2026-04-27T09:14:30+00:00

Drop superfluous address-cells and size-cells to fix DTC W=1 warning: arch/arm/boot/dts/renesas/r7s72100-genmai.dts:28.17-55.4: Warning (avoid_unnecessary_addr_size): /flash@18000000: unnecessary #address-cells/#size-cells without "ranges", "dma-ranges" or child "reg" or "ranges" property Signed-off-by: Marek Vasut Fixes: 30e0a8cf886cb459 ("ARM: dts: renesas: genmai: Add FLASH nodes") Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260327234244.91707-6-marek.vasut+renesas@mailbox.org Signed-off-by: Geert Uytterhoeven

ARM: dts: renesas: r7s72100: Add missing unit address to bus node

2026-04-27T09:14:30+00:00

Add missing unit address to bus node to fix the following DTC W=1 warning: arch/arm/boot/dts/renesas/r7s72100.dtsi:40.11-46.4: Warning (unit_address_vs_reg): /bus: node has a reg or ranges property, but no unit name Signed-off-by: Marek Vasut Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260327234244.91707-5-marek.vasut+renesas@mailbox.org Signed-off-by: Geert Uytterhoeven

ARM: dts: renesas: r8a7792: Add missing unit address to bus node

2026-04-27T09:14:30+00:00

Add missing unit address to bus node to fix the following DTC W=1 warning: arch/arm/boot/dts/renesas/r8a7792.dtsi:89.12-94.4: Warning (unit_address_vs_reg): /bus: node has a reg or ranges property, but no unit name Signed-off-by: Marek Vasut Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260327234244.91707-4-marek.vasut+renesas@mailbox.org Signed-off-by: Geert Uytterhoeven

ARM: dts: renesas: r8a7779: Add missing unit address to bus node

2026-04-27T09:14:30+00:00

Add missing unit address to bus node to fix the following DTC W=1 warning: arch/arm/boot/dts/renesas/r8a7779.dtsi:707.12-712.4: Warning (unit_address_vs_reg): /bus: node has a reg or ranges property, but no unit name Signed-off-by: Marek Vasut Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260327234244.91707-3-marek.vasut+renesas@mailbox.org Signed-off-by: Geert Uytterhoeven

ARM: dts: renesas: r8a7778: Add missing unit address to bus node

2026-04-27T09:14:30+00:00

Add missing unit address to bus node to fix the following DTC W=1 warning: arch/arm/boot/dts/renesas/r8a7778.dtsi:43.12-48.4: Warning (unit_address_vs_reg): /bus: node has a reg or ranges property, but no unit name Signed-off-by: Marek Vasut Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260327234244.91707-2-marek.vasut+renesas@mailbox.org Signed-off-by: Geert Uytterhoeven

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux

2026-04-25T14:44:26+00:00

Pull ARM updates from Russell King: - fix a race condition handling PG_dcache_clean - further cleanups for the fault handling, allowing RT to be enabled - fixing nzones validation in adfs filesystem driver - fix for module unwinding * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux: ARM: 9463/1: Allow to enable RT ARM: 9472/1: fix race condition on PG_dcache_clean in __sync_icache_dcache() ARM: 9471/1: module: fix unwind section relocation out of range error fs/adfs: validate nzones in adfs_validate_bblk() ARM: provide individual is_translation_fault() and is_permission_fault() ARM: move FSR fault status definitions before fsr_fs() ARM: use BIT() and GENMASK() for fault status register fields ARM: move is_permission_fault() and is_translation_fault() to fault.h ARM: move vmalloc() lazy-page table population ARM: ensure interrupts are enabled in __do_user_fault()