lkml.org 
[lkml]   [2020]   [Sep]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH 0/2] Enable support IPI_CPU_CRASH_STOP to be pseudo-NMI
Date
Enable support IPI_CPU_CRASH_STOP to be pseudo-NMI

This patchset enables IPI_CPU_CRASH_STOP IPI to be pseudo-NMI.
This allows kdump to collect system information even when the CPU is in
a HARDLOCKUP state.

Only IPI_CPU_CRASH_STOP uses NMI and the other IPIs remain normal IRQs.

The patch has been tested on ThunderX.

This patch assumes Marc's latest IPIs patch-set. [1]
It also uses some of Sumit's IPI patch set for NMI.[2]

[1] https://lore.kernel.org/linux-arm-kernel/20200901144324.1071694-1-maz@kernel.org/
[2] https://lore.kernel.org/linux-arm-kernel/1599830924-13990-3-git-send-email-sumit.garg@linaro.org/

$ echo 1 > /proc/sys/kernel/panic_on_rcu_stal
$ echo HARDLOCKUP > /sys/kernel/debug/provoke-crash/DIRECT
: kernel panics and crash kernel boot
: makedumpfile saves the system state at HARDLOCKUP in vmcore.

crash utility:
crash> bt
PID: 3213 TASK: fffffd001adc5940 CPU: 8 COMMAND: "bash"
#0 [fffffe0022fefcf0] lkdtm_HARDLOCKUP at fffffe0010888ab4
#1 [fffffe0022fefd10] lkdtm_do_action at fffffe00108882bc
#2 [fffffe0022fefd20] direct_entry at fffffe0010888720
#3 [fffffe0022fefd70] full_proxy_write at fffffe001058cfe4
#4 [fffffe0022fefdb0] vfs_write at fffffe00104a4c2c
#5 [fffffe0022fefdf0] ksys_write at fffffe00104a4f0c
#6 [fffffe0022fefe40] __arm64_sys_write at fffffe00104a4fbc
#7 [fffffe0022fefe50] el0_svc_common.constprop.0 at fffffe0010159e38
#8 [fffffe0022fefe80] do_el0_svc at fffffe0010159fa0
#9 [fffffe0022fefe90] el0_svc at fffffe00101481d0
#10 [fffffe0022fefea0] el0_sync_handler at fffffe00101484b4
#11 [fffffe0022fefff0] el0_sync at fffffe0010142b7c


Sumit Garg (1):
irqchip/gic-v3: Enable support for SGIs to act as NMIs

Yuichi Ito (1):
Register IPI_CPU_CRASH_STOP IPI as pseudo-NMI

arch/arm64/kernel/smp.c | 39 ++++++++++++++++++++++++++++--------
drivers/irqchip/irq-gic-v3.c | 13 ++++++++++--
2 files changed, 42 insertions(+), 10 deletions(-)

--
2.25.1

\
 
 \ /
  Last update: 2020-09-24 06:55    [W:0.079 / U:0.396 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site