mchoo7 wrote: `/dev/mem` is only accessible with root privilege, so security doesn't really matter here. Thus the readonly option I added here isn't tied to security because lldb wouldn't load `/dev/mem` if there is no root privilege at the first place.
E.g.: ```console $ lldb /boot/kernel/kernel -c /dev/mem (lldb) target create "/boot/kernel/kernel" --core "/dev/mem" error: Cannot open '/dev/mem': Permission denied. ``` That's why I chose the word "safety". System stability can be a synonym here. > I'm ok with the code, and the settings part we already had reviewed. I just > want to know about: > > > Implement ProcessFreeBSDKernelCore::DoWriteMemory() to write data on kernel > > dump or /dev/mem. > > Can you define what "kernel dump" is here? Because I'm thinking of it like an > elf core, and writing to "memory" in an elf core I suppose could be done but > is generally not allowed. > > Can you explain that a bit more? > > I agree with this setting's importance for /dev/mem, which I understand to be > a window into the live kernel. By kernel dump, I mean kernel crash dump described [here](https://docs.freebsd.org/en/books/developers-handbook/kerneldebug/). I'll reword the PR description. Kernel crash dump is/isn't kernel crash dump depending on its format. Full kernel crash dump is a elf core. The whole system memory (including unused pages) are dumped onto physical storage. The downside of this is that there are systems using hundreds of GB or a few TB of ram, and sometimes it's difficult to secure a block storage with that capacity. So FreeBSD got another kernel crash dump format called minidump (itis different from lldb's minidump plugin which is windows crash dump only). Minidump is not elf core so it needs FreeBSD's `kvm` to handle memory read/write. This is the main blocker that prevents us from making FreeBSDKernelCore plugin cross-platform. A possible solution for this is creating a utility that converts minidump to elf format, but that's not in my scope for now. https://github.com/llvm/llvm-project/pull/183553 _______________________________________________ lldb-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
