mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-02-28 19:06:51 +01:00
7dff99b354
This config option goes way back - it used to be an internal debug
option to random.c (at that point called DEBUG_RANDOM_BOOT), then was
renamed and exposed as a config option as CONFIG_WARN_UNSEEDED_RANDOM,
and then further renamed to the current CONFIG_WARN_ALL_UNSEEDED_RANDOM.
It was all done with the best of intentions: the more limited
rate-limited reports were reporting some cases, but if you wanted to see
all the gory details, you'd enable this "ALL" option.
However, it turns out - perhaps not surprisingly - that when people
don't care about and fix the first rate-limited cases, they most
certainly don't care about any others either, and so warning about all
of them isn't actually helping anything.
And the non-ratelimited reporting causes problems, where well-meaning
people enable debug options, but the excessive flood of messages that
nobody cares about will hide actual real information when things go
wrong.
I just got a kernel bug report (which had nothing to do with randomness)
where two thirds of the the truncated dmesg was just variations of
random: get_random_u32 called from __get_random_u32_below+0x10/0x70 with crng_init=0
and in the process early boot messages had been lost (in addition to
making the messages that _hadn't_ been lost harder to read).
The proper way to find these things for the hypothetical developer that
cares - if such a person exists - is almost certainly with boot time
tracing. That gives you the option to get call graphs etc too, which is
likely a requirement for fixing any problems anyway.
See Documentation/trace/boottime-trace.rst for that option.
And if we for some reason do want to re-introduce actual printing of
these things, it will need to have some uniqueness filtering rather than
this "just print it all" model.
Fixes: cc1e127bfa ("random: remove ratelimiting for in-kernel unseeded randomness")
Acked-by: Jason Donenfeld <Jason@zx2c4.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
119 lines
2.7 KiB
Plaintext
119 lines
2.7 KiB
Plaintext
# Help: Debugging for CI systems and finding regressions
|
|
#
|
|
# The config is based on running daily CI for enterprise Linux distros to
|
|
# seek regressions on linux-next builds on different bare-metal and virtual
|
|
# platforms. It can be used for example,
|
|
#
|
|
# $ make ARCH=arm64 defconfig debug.config
|
|
#
|
|
# Keep alphabetically sorted inside each section.
|
|
#
|
|
# printk and dmesg options
|
|
#
|
|
CONFIG_DEBUG_BUGVERBOSE=y
|
|
CONFIG_DYNAMIC_DEBUG=y
|
|
CONFIG_PRINTK_CALLER=y
|
|
CONFIG_PRINTK_TIME=y
|
|
CONFIG_SYMBOLIC_ERRNAME=y
|
|
#
|
|
# Compile-time checks and compiler options
|
|
#
|
|
CONFIG_DEBUG_INFO=y
|
|
CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
|
|
CONFIG_DEBUG_SECTION_MISMATCH=y
|
|
CONFIG_FRAME_WARN=2048
|
|
CONFIG_SECTION_MISMATCH_WARN_ONLY=y
|
|
#
|
|
# Generic Kernel Debugging Instruments
|
|
#
|
|
# CONFIG_UBSAN_ALIGNMENT is not set
|
|
# CONFIG_UBSAN_DIV_ZERO is not set
|
|
# CONFIG_UBSAN_TRAP is not set
|
|
CONFIG_DEBUG_FS=y
|
|
CONFIG_DEBUG_FS_ALLOW_ALL=y
|
|
CONFIG_DEBUG_IRQFLAGS=y
|
|
CONFIG_UBSAN=y
|
|
CONFIG_UBSAN_BOOL=y
|
|
CONFIG_UBSAN_BOUNDS=y
|
|
CONFIG_UBSAN_ENUM=y
|
|
CONFIG_UBSAN_SHIFT=y
|
|
CONFIG_UBSAN_UNREACHABLE=y
|
|
#
|
|
# Networking Debugging
|
|
#
|
|
CONFIG_NET_DEV_REFCNT_TRACKER=y
|
|
CONFIG_NET_NS_REFCNT_TRACKER=y
|
|
CONFIG_DEBUG_NET=y
|
|
#
|
|
# Memory Debugging
|
|
#
|
|
# CONFIG_DEBUG_PAGEALLOC is not set
|
|
# CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF is not set
|
|
# CONFIG_DEBUG_RODATA_TEST is not set
|
|
# CONFIG_DEBUG_WX is not set
|
|
# CONFIG_KFENCE is not set
|
|
# CONFIG_PAGE_POISONING is not set
|
|
# CONFIG_SLUB_STATS is not set
|
|
CONFIG_PAGE_EXTENSION=y
|
|
CONFIG_PAGE_OWNER=y
|
|
CONFIG_DEBUG_KMEMLEAK=y
|
|
CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN=y
|
|
CONFIG_DEBUG_OBJECTS=y
|
|
CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT=1
|
|
CONFIG_DEBUG_OBJECTS_FREE=y
|
|
CONFIG_DEBUG_OBJECTS_PERCPU_COUNTER=y
|
|
CONFIG_DEBUG_OBJECTS_RCU_HEAD=y
|
|
CONFIG_DEBUG_OBJECTS_TIMERS=y
|
|
CONFIG_DEBUG_OBJECTS_WORK=y
|
|
CONFIG_DEBUG_PER_CPU_MAPS=y
|
|
CONFIG_DEBUG_STACK_USAGE=y
|
|
CONFIG_DEBUG_VIRTUAL=y
|
|
CONFIG_DEBUG_VM=y
|
|
CONFIG_DEBUG_VM_PGFLAGS=y
|
|
CONFIG_DEBUG_VM_RB=y
|
|
CONFIG_DEBUG_VM_VMACACHE=y
|
|
CONFIG_KASAN=y
|
|
CONFIG_KASAN_GENERIC=y
|
|
CONFIG_KASAN_INLINE=y
|
|
CONFIG_KASAN_VMALLOC=y
|
|
CONFIG_PTDUMP_DEBUGFS=y
|
|
CONFIG_SCHED_STACK_END_CHECK=y
|
|
CONFIG_SLUB_DEBUG_ON=y
|
|
#
|
|
# Debug Oops, Lockups and Hangs
|
|
#
|
|
CONFIG_BOOTPARAM_HUNG_TASK_PANIC=0
|
|
CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=0
|
|
CONFIG_DEBUG_ATOMIC_SLEEP=y
|
|
CONFIG_DETECT_HUNG_TASK=y
|
|
CONFIG_PANIC_ON_OOPS=y
|
|
CONFIG_PANIC_TIMEOUT=0
|
|
CONFIG_SOFTLOCKUP_DETECTOR=y
|
|
#
|
|
# Lock Debugging (spinlocks, mutexes, etc...)
|
|
#
|
|
# CONFIG_PROVE_RAW_LOCK_NESTING is not set
|
|
CONFIG_PROVE_LOCKING=y
|
|
#
|
|
# Debug kernel data structures
|
|
#
|
|
CONFIG_BUG_ON_DATA_CORRUPTION=y
|
|
#
|
|
# RCU Debugging
|
|
#
|
|
CONFIG_RCU_EXPERT=y
|
|
CONFIG_PROVE_RCU=y
|
|
CONFIG_PROVE_RCU_LIST=y
|
|
#
|
|
# Tracers
|
|
#
|
|
CONFIG_BRANCH_PROFILE_NONE=y
|
|
CONFIG_DYNAMIC_FTRACE=y
|
|
CONFIG_FTRACE=y
|
|
CONFIG_FUNCTION_TRACER=y
|
|
#
|
|
# Preemption
|
|
#
|
|
CONFIG_DEBUG_PREEMPT=y
|
|
CONFIG_PREEMPT=y
|