llvm-project

9d9c7fc0 - [lldb][Process/FreeBSDKernel] Print unread message buffer on start (#178027)

[lldb][Process/FreeBSDKernel] Print unread message buffer on start (#178027) This is equivalent of kgdb_dmesg() in fbsd-kvm.c in FreeBSD kgdb(1) port. Unread kernel messages is only printed in interactive mode (i.e. not in batch mode) to mimic KGDB's behaviour. Example output: ``` ➜ sudo ./build/bin/lldb /boot/kernel/kernel -c /var/crash/vmcore.last (lldb) target create "/boot/kernel/kernel" --core "/var/crash/vmcore.last" Unread portion of the kernel message buffer: panic: kdb_sysctl_panic cpuid = 1 time = 1769364579 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe01b435fa20 vpanic() at vpanic+0x136/frame 0xfffffe01b435fb50 panic() at panic+0x43/frame 0xfffffe01b435fbb0 kdb_sysctl_panic() at kdb_sysctl_panic+0x63/frame 0xfffffe01b435fbe0 sysctl_root_handler_locked() at sysctl_root_handler_locked+0x9c/frame 0xfffffe01b435fc30 sysctl_root() at sysctl_root+0x22f/frame 0xfffffe01b435fcb0 userland_sysctl() at userland_sysctl+0x196/frame 0xfffffe01b435fd50 sys___sysctl() at sys___sysctl+0x65/frame 0xfffffe01b435fe00 amd64_syscall() at amd64_syscall+0x169/frame 0xfffffe01b435ff30 fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe01b435ff30 --- syscall (202, FreeBSD ELF64, __sysctl), rip = 0x3f67cad1c8da, rsp = 0x3f67c80261d8, rbp = 0x3f67c8026220 --- KDB: enter: panic Core file '/var/crash/vmcore.last' (x86_64) was loaded. (lldb) ``` --------- Signed-off-by: Minsoo Choo <minsoochoo0122@proton.me>