mirror-linux/arch/um
Masami Hiramatsu (Google) a494d3c8d5 ring-buffer: Flush and stop persistent ring buffer on panic
On real hardware, panic and machine reboot may not flush hardware cache
to memory. This means the persistent ring buffer, which relies on a
coherent state of memory, may not have its events written to the buffer
and they may be lost. Moreover, there may be inconsistency with the
counters which are used for validation of the integrity of the
persistent ring buffer which may cause all data to be discarded.

To avoid this issue, stop recording of the ring buffer on panic and
flush the cache of the ring buffer's memory.

Fixes: e645535a95 ("tracing: Add option to use memmapped memory for trace boot instance")
Cc: stable@vger.kernel.org
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ian Rogers <irogers@google.com>
Link: https://patch.msgid.link/177751969602.2136606.12031934362587643488.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-05-21 08:20:58 -04:00
..
configs um: Remove CONFIG_FRAME_WARN from x86_64_defconfig 2026-03-21 10:43:10 +01:00
drivers um: drivers: call kernel_strrchr() explicitly in cow_user.c 2026-04-08 09:25:22 +02:00
include ring-buffer: Flush and stop persistent ring buffer on panic 2026-05-21 08:20:58 -04:00
kernel Mostly cleanups and small things, notably: 2026-04-20 16:36:46 -07:00
os-Linux arch/um: remove unused varible err in remove_files_and_dir() 2026-01-13 19:43:41 +01:00
scripts um: prevent user code in modules 2023-04-20 23:06:38 +02:00
.gitignore
Kbuild um: use obj-y to descend into arch/um/*/ 2023-08-26 22:41:34 +02:00
Kconfig um: Disable GCOV_PROFILE_ALL on 32-bit UML with Clang 20/21 2026-04-10 09:28:59 +02:00
Kconfig.debug
Makefile um: Don't rename vmap to kernel_vmap 2025-11-25 10:18:37 +01:00
Makefile-os-Linux
Makefile-skas um: fix stub exe build with CONFIG_GCOV 2024-10-26 16:06:10 +02:00