linux-dev - Linux kernel development work

Age	Commit message (Collapse)	Author	Files	Lines
2015-10-03	ARM: 8439/1: Fix backtrace generation when IPI is masked	Daniel Thompson	1	-1/+10
	Currently on ARM when <SysRq-L> is triggered from an interrupt handler (e.g. a SysRq issued using UART or kbd) the main CPU will wedge for ten seconds with interrupts masked before issuing a backtrace for every CPU except itself. The new backtrace code introduced by commit 96f0e00378d4 ("ARM: add basic support for on-demand backtrace of other CPUs") does not work correctly when run from an interrupt handler because IPI_CPU_BACKTRACE is used to generate the backtrace on all CPUs but cannot preempt the current calling context. This can be fixed by detecting that the calling context cannot be preempted and issuing the backtrace directly in this case. Issuing directly leaves us without any pt_regs to pass to nmi_cpu_backtrace() so we also modify the generic code to call dump_stack() when its argument is NULL. Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17	nmi: create generic NMI backtrace implementation	Russell King	1	-0/+162
	x86s NMI backtrace implementation (for arch_trigger_all_cpu_backtrace()) is fairly generic in nature - the only architecture specific bits are the act of raising the NMI to other CPUs, and reporting the status of the NMI handler. These are fairly simple to factor out, and produce a generic implementation which can be shared between ARM and x86. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>