linux_dsm_epyc7002/arch/arm
Stephen Boyd 398f74569c ARM: 8393/1: smp: Fix suspicious RCU usage with ipi tracepoints
John Stultz reports an RCU splat on boot with ARM ipi trace
events enabled.

===============================
[ INFO: suspicious RCU usage. ]
4.1.0-rc7-00033-gb5bed2f #153 Not tainted
-------------------------------
include/trace/events/ipi.h:68 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
no locks held by swapper/0/0.

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.0-rc7-00033-gb5bed2f #153
Hardware name: Qualcomm (Flattened Device Tree)
[<c0216b08>] (unwind_backtrace) from [<c02136e8>] (show_stack+0x10/0x14)
[<c02136e8>] (show_stack) from [<c075e678>] (dump_stack+0x70/0xbc)
[<c075e678>] (dump_stack) from [<c0215a80>] (handle_IPI+0x428/0x604)
[<c0215a80>] (handle_IPI) from [<c020942c>] (gic_handle_irq+0x54/0x5c)
[<c020942c>] (gic_handle_irq) from [<c0766604>] (__irq_svc+0x44/0x7c)
Exception stack(0xc09f3f48 to 0xc09f3f90)
3f40:                   00000001 00000001 00000000 c09f73b8 c09f4528 c0a5de9c
3f60: c076b4f0 00000000 00000000 c09ef108 c0a5cec1 00000001 00000000 c09f3f90
3f80: c026bf60 c0210ab8 20000113 ffffffff
[<c0766604>] (__irq_svc) from [<c0210ab8>] (arch_cpu_idle+0x20/0x3c)
[<c0210ab8>] (arch_cpu_idle) from [<c02647f0>] (cpu_startup_entry+0x2c0/0x5dc)
[<c02647f0>] (cpu_startup_entry) from [<c099bc1c>] (start_kernel+0x358/0x3c4)
[<c099bc1c>] (start_kernel) from [<8020807c>] (0x8020807c)

At this point in the IPI handling path we haven't called
irq_enter() yet, so RCU doesn't know that we're about to exit
idle and properly warns that we're using RCU from an idle CPU.
Use trace_ipi_entry_rcuidle() instead of trace_ipi_entry() so
that RCU is informed about our exit from idle.

Fixes: 365ec7b173 ("ARM: add IPI tracepoints")
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-29 11:02:55 +01:00
..
boot Omap fixes for the -rc cycle, including a fix for potential hardware 2015-06-08 10:32:55 -07:00
common ARM: SoC platform updates for v4.1 2015-04-22 09:08:39 -07:00
configs ARM: multi_v7_defconfig: Replace CONFIG_USB_ISP1760_HCD by CONFIG_USB_ISP1760 2015-05-29 14:31:35 +02:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-04-15 10:42:15 -07:00
firmware
include Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-05-10 11:16:48 -07:00
kernel ARM: 8393/1: smp: Fix suspicious RCU usage with ipi tracepoints 2015-06-29 11:02:55 +01:00
kvm This mostly includes the PPC changes for 4.1, which this time cover 2015-04-26 13:06:22 -07:00
lib ARM: ensure delay timer has sufficient accuracy for delays 2015-04-14 22:28:07 +01:00
mach-alpine ARM: alpine: add support for generic pci 2015-04-14 01:15:57 +02:00
mach-asm9260
mach-at91 Fourth batch of cleanup for 4.1: 2015-04-14 01:50:21 +02:00
mach-axxia
mach-bcm ARM: cygnus: fix const declaration bcm_cygnus_dt_compat 2015-03-24 15:13:23 -07:00
mach-berlin
mach-clps711x
mach-cns3xxx
mach-davinci ARM: DT updates for v4.1 2015-04-22 09:09:46 -07:00
mach-digicolor
mach-dove
mach-ebsa110
mach-efm32
mach-ep93xx
mach-exynos Fix for Exynos3250 RTC wake-up interrupts after converting PMU 2015-06-01 17:05:43 +02:00
mach-footbridge
mach-gemini ARM: gemini: fix compiler warning due wrong data type 2015-05-12 16:45:23 +02:00
mach-highbank
mach-hisi
mach-imx ARM: imx6: gpc: don't register power domain if DT data is missing 2015-05-27 16:33:46 +08:00
mach-integrator
mach-iop13xx
mach-iop32x
mach-iop33x
mach-ixp4xx
mach-keystone
mach-ks8695
mach-lpc32xx
mach-mediatek
mach-meson
mach-mmp
mach-moxart
mach-mv78xx0
mach-mvebu ARM: SoC platform updates for v4.1 2015-04-22 09:08:39 -07:00
mach-mxs
mach-netx
mach-nomadik
mach-nspire
mach-omap1
mach-omap2 ARM: OMAP3: Fix booting with thumb2 kernel 2015-05-28 07:22:08 -07:00
mach-orion5x
mach-picoxcell
mach-prima2
mach-pxa ARM: pxa: pxa_cplds: signedness bug in probe 2015-05-22 16:41:20 +02:00
mach-qcom
mach-realview
mach-rockchip Revert "ARM: rockchip: fix undefined instruction of reset_ctrl_regs" 2015-05-13 15:47:03 +02:00
mach-rpc
mach-s3c24xx
mach-s3c64xx ARM: SoC platform updates for v4.1 2015-04-22 09:08:39 -07:00
mach-s5pv210 ARM: 8326/1: s5pv210: move resume code to .text section 2015-03-29 23:11:58 +01:00
mach-sa1100
mach-shmobile Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma 2015-04-24 09:49:37 -07:00
mach-socfpga
mach-spear
mach-sti
mach-sunxi
mach-tegra Power management and ACPI updates for v4.1-rc1 2015-04-14 20:21:54 -07:00
mach-u300
mach-ux500
mach-versatile
mach-vexpress ARM: SoC driver updates for v4.1 2015-04-22 09:18:17 -07:00
mach-vt8500
mach-w90x900
mach-zynq
mm ARM: 8356/1: mm: handle non-pmd-aligned end of RAM 2015-05-14 16:15:20 +01:00
net ARM: net: delegate filter to kernel interpreter when imm_offset() return value can't fit into 12bits. 2015-05-10 19:21:49 -04:00
nwfpe ARM: 8322/1: keep .text and .fixup regions closer together 2015-03-29 23:11:56 +01:00
oprofile
plat-iop
plat-omap ARM, clocksource/drivers: Provide read_boot_clock64() and read_persistent_clock64() and use them 2015-04-03 08:18:23 +02:00
plat-orion
plat-pxa ARM: plat-pxa: remove use of seq_printf return value 2015-04-15 16:35:25 -07:00
plat-samsung
plat-versatile
probes
tools
vdso ARM: 8344/1: VDSO: honor CONFIG_VDSO in Makefile 2015-04-21 15:28:02 +01:00
vfp
xen xen/arm: Define xen_arch_suspend() 2015-05-18 13:38:09 +01:00
Kconfig ARM: SoC multiplatform code changes for v4.1 2015-04-22 09:20:15 -07:00
Kconfig-nommu
Kconfig.debug ARM: SoC multiplatform code changes for v4.1 2015-04-22 09:20:15 -07:00
Makefile ARM: SoC platform updates for v4.1 2015-04-22 09:08:39 -07:00