linux/arch/arm64
Chunyan Zhang 2b9743441a arm64: use preempt_disable_notrace in _percpu_read/write
When debug preempt or preempt tracer is enabled, preempt_count_add/sub()
can be traced by function and function graph tracing, and
preempt_disable/enable() would call preempt_count_add/sub(), so in Ftrace
subsystem we should use preempt_disable/enable_notrace instead.

In the commit 345ddcc882 ("ftrace: Have set_ftrace_pid use the bitmap
like events do") the function this_cpu_read() was added to
trace_graph_entry(), and if this_cpu_read() calls preempt_disable(), graph
tracer will go into a recursive loop, even if the tracing_on is
disabled.

So this patch change to use preempt_enable/disable_notrace instead in
this_cpu_read().

Since Yonghui Yang helped a lot to find the root cause of this problem,
so also add his SOB.

Signed-off-by: Yonghui Yang <mark.yang@spreadtrum.com>
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-09-09 12:34:47 +01:00
..
boot arm64: dts: rockchip: add reset saradc node for rk3368 SoCs 2016-08-23 19:08:21 +01:00
configs arm64: defconfig: enable CONFIG_LOCALVERSION_AUTO 2016-08-12 19:08:48 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-03-17 11:22:54 -07:00
include arm64: use preempt_disable_notrace in _percpu_read/write 2016-09-09 12:34:47 +01:00
kernel arm64: avoid TLB conflict with CONFIG_RANDOMIZE_BASE 2016-08-25 11:11:32 +01:00
kvm arm64: KVM: report configured SRE value to 32-bit world 2016-08-17 12:46:23 +02:00
lib arm64/uaccess: Enable hardened usercopy 2016-07-26 14:41:49 -07:00
mm arm64: kernel: Fix unmasked debug exceptions when restoring mdscr_el1 2016-09-02 17:19:55 +01:00
net arm64: bpf: optimize LD_ABS, LD_IND 2016-06-10 23:11:50 -07:00
xen arm/xen: add support for vm_assist hypercall 2016-07-06 10:42:14 +01:00
Kconfig Implements HARDENED_USERCOPY verification of copy_to_user/copy_from_user 2016-08-08 14:48:14 -07:00
Kconfig.debug arm64: enable CONFIG_SET_MODULE_RONX by default 2016-05-31 14:23:29 +01:00
Kconfig.platforms arm64: Kconfig: select HISILICON_IRQ_MBIGEN only if PCI is selected 2016-08-10 22:58:12 +02:00
Makefile arm64 fixes: 2016-08-06 08:58:59 -04:00