This patchset implements arch_trigger_all_cpu_backtrace for arm.
Non-maskable signalling relies on the kernel being able to access FIQ and therefore, for devices that implement TrustZone, it will work only on systems that boot the kernel in secure mode.
Tested on Freescale iMX.6 (both via SysRq-l and by deliberately locking up the kernel with CONFIG_DEBUG_SPINLOCK=y).
Changes *before* v1:
- This patchset is a hugely cut-down successor to "[PATCH v11 00/19] arm: KGDB NMI/FIQ support". Thanks to Thomas Gleixner for suggesting the new structure. For historic details see: https://lkml.org/lkml/2014/9/2/227
- Fix bug in __fiq_abt (no longer passes a bad struct pt_regs value). In fixing this we also remove the useless indirection previously found in the fiq_handler macro.
- Make default fiq handler "always on" by migrating from fiq.c to traps.c and replace do_unexp_fiq with the new handler (Russell King).
- Add arm64 version of fiq.h (Russell King)
- Removed conditional branching and code from irq-gic.c, this is replaced by much simpler code that relies on the GIC specification's heavy use of read-as-zero/write-ignored (Russell King)
Daniel Thompson (5): arm: fiq: Replace default FIQ handler arm: smp: Introduce a non-maskable IPI arm64: Introduce dummy version of asm/fiq.h irqchip: gic: Add support for IPI FIQ irqchip: gic: Group 0 workaround.
Russell King (1): arm: Implement arch_trigger_all_cpu_backtrace
arch/arm/Kconfig.debug | 14 +++ arch/arm/include/asm/hardirq.h | 2 +- arch/arm/include/asm/irq.h | 5 + arch/arm/include/asm/smp.h | 7 ++ arch/arm/kernel/entry-armv.S | 110 ++++++++++++++++++-- arch/arm/kernel/setup.c | 8 +- arch/arm/kernel/smp.c | 67 ++++++++++++ arch/arm/kernel/traps.c | 34 +++++- arch/arm64/include/asm/fiq.h | 18 ++++ drivers/irqchip/irq-gic.c | 223 +++++++++++++++++++++++++++++++++++++--- include/linux/irqchip/arm-gic.h | 3 + 11 files changed, 464 insertions(+), 27 deletions(-) create mode 100644 arch/arm64/include/asm/fiq.h
-- 1.9.3