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Douglas Anderson ef4e484ab0 kgdb: Flush console before entering kgdb on panic
[ Upstream commit dd712d3d45 ]

When entering kdb/kgdb on a kernel panic, it was be observed that the
console isn't flushed before the `kdb` prompt came up. Specifically,
when using the buddy lockup detector on arm64 and running:
  echo HARDLOCKUP > /sys/kernel/debug/provoke-crash/DIRECT

I could see:
  [   26.161099] lkdtm: Performing direct entry HARDLOCKUP
  [   32.499881] watchdog: Watchdog detected hard LOCKUP on cpu 6
  [   32.552865] Sending NMI from CPU 5 to CPUs 6:
  [   32.557359] NMI backtrace for cpu 6
  ... [backtrace for cpu 6] ...
  [   32.558353] NMI backtrace for cpu 5
  ... [backtrace for cpu 5] ...
  [   32.867471] Sending NMI from CPU 5 to CPUs 0-4,7:
  [   32.872321] NMI backtrace forP cpuANC: Hard LOCKUP

  Entering kdb (current=..., pid 0) on processor 5 due to Keyboard Entry
  [5]kdb>

As you can see, backtraces for the other CPUs start printing and get
interleaved with the kdb PANIC print.

Let's replicate the commands to flush the console in the kdb panic
entry point to avoid this.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230822131945.1.I5b460ae8f954e4c4f628a373d6e74713c06dd26f@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:19:47 +00:00
arch ARM: 9320/1: fix stack depot IRQ stack filter 2023-11-28 17:19:43 +00:00
block blk-core: use pr_warn_ratelimited() in bio_check_ro() 2023-11-20 11:59:36 +01:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 17:19:42 +00:00
Documentation i2c: i801: Add support for Intel Birch Stream SoC 2023-11-28 17:19:46 +00:00
drivers drm/amd/display: Avoid NULL dereference of timing generator 2023-11-28 17:19:47 +00:00
fs gfs2: Fix slab-use-after-free in gfs2_qd_dealloc 2023-11-28 17:19:47 +00:00
include media: ipu-bridge: increase sensor_name size 2023-11-28 17:19:46 +00:00
init x86/retpoline: Make sure there are no unconverted return thunks due to KCSAN 2023-11-28 17:19:36 +00:00
io_uring io_uring/net: ensure socket is marked connected on connect retry 2023-11-20 11:59:38 +01:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel kgdb: Flush console before entering kgdb on panic 2023-11-28 17:19:47 +00:00
lib lib/generic-radix-tree.c: Don't overflow in peek() 2023-11-28 17:19:35 +00:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm vfs: fix readahead(2) on block devices 2023-11-20 11:58:52 +01:00
net 9p: v9fs_listxattr: fix %s null argument warning 2023-11-28 17:19:46 +00:00
rust rust: docs: fix logo replacement 2023-10-19 16:40:00 +02:00
samples VFIO updates for v6.6-rc1 2023-08-30 20:36:01 -07:00
scripts x86/retpoline: Make sure there are no unconverted return thunks due to KCSAN 2023-11-28 17:19:36 +00:00
security apparmor: fix invalid reference on profile->disconnected 2023-11-20 11:59:24 +01:00
sound ASoC: Intel: soc-acpi-cht: Add Lenovo Yoga Tab 3 Pro YT3-X90 quirk 2023-11-28 17:19:44 +00:00
tools selftests/efivarfs: create-read: fix a resource leak 2023-11-28 17:19:42 +00:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap 20 hotfixes. 12 are cc:stable and the remainder address post-6.5 issues 2023-10-24 09:52:16 -10:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Char/Misc driver fixes for 6.6-final 2023-10-28 07:51:27 -10:00
Makefile Linux 6.6.2 2023-11-20 11:59:39 +01:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.