linux/arch/um
Mordechay Goodstein 6555acdefc um: time-travel: support time-travel protocol broadcast messages
Add a message type to the time-travel protocol to broadcast
a small (64-bit) value to all participants in a simulation.
The main use case is to have an identical message come to
all participants in a simulation, e.g. to separate out logs
for different tests running in a single simulation.

Down in the guts of time_travel_handle_message() we can't
use printk() and not even printk_deferred(), so just store
the message and print it at the start of the userspace()
function.

Unfortunately this means that other prints in the kernel
can actually bypass the message, but in most cases where
this is used, for example to separate test logs, userspace
will be involved. Also, even if we could use
printk_deferred(), we'd still need to flush it out in the
userspace() function since otherwise userspace messages
might cross it.

As a result, this is a reasonable compromise, there's no
need to have any core changes and it solves the main use
case we have for it.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Link: https://patch.msgid.link/20240702192118.c4093bc5b15e.I2ca8d006b67feeb866ac2017af7b741c9e06445a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-07-03 12:24:22 +02:00
..
configs um: Fix hostaudio build errors 2023-08-19 23:30:22 +02:00
drivers ubd: Remove unused mutex 'ubd_mutex' 2024-07-03 12:21:29 +02:00
include um: time-travel: support time-travel protocol broadcast messages 2024-07-03 12:24:22 +02:00
kernel um: time-travel: support time-travel protocol broadcast messages 2024-07-03 12:24:22 +02:00
os-Linux um: time-travel: support time-travel protocol broadcast messages 2024-07-03 12:24:22 +02:00
scripts um: prevent user code in modules 2023-04-20 23:06:38 +02:00
.gitignore um: gitignore: Add kernel/capflags.c 2021-12-21 21:22:43 +01:00
Kbuild um: use obj-y to descend into arch/um/*/ 2023-08-26 22:41:34 +02:00
Kconfig um: enable UBSAN 2024-07-03 12:23:40 +02:00
Kconfig.debug um: Disable CONFIG_GCOV with MODULES 2021-04-15 23:10:33 +02:00
Makefile um: Makefile: use bash from the environment 2024-04-22 22:17:29 +02:00
Makefile-os-Linux
Makefile-skas arch: um: Add Clang coverage support 2024-01-05 00:30:35 +01:00