vasilito
d41d0aa728
The relibc fork's pthread_setname_np / pthread_getname_np /
pthread_setaffinity_np / pthread_getaffinity_np and
mutex_owner_id_is_live all use the path format
'proc:{thread_fd}/<sub-handle>' (e.g.
'proc:123/name' or 'proc:123/sched-affinity') via a single
Sys::open() call.
Previously the proc scheme's OpenTy::Auth handler in
src/scheme/proc.rs only recognized 'new-context' and
'cur-context' as literal strings, so '123/name' would
hit the _ => ENOENT arm and the relibc calls would
fail with ENOENT at runtime.
Fix: add a third arm in OpenTy::Auth that splits the
operation string on the first '/', parses the prefix as
a numeric context id, looks up the corresponding
ContextHandle in the HANDLES map, and recursively
dispatches to openat_context with the suffix as the
sub-handle path. This makes 'proc:123/name' resolve to
the same handle chain that 'dup(123, "name")' would
have produced.
The recursive call is safe because openat_context
doesn't depend on the Authority-only state. The
HANDLES map is read-locked; we drop the lock before
the recursive call by scoping the handles variable.
Discovered by Oracle review of Phase 0c patches
(Issue 1). The bug was latent in the original
P5-proc-setschedpolicy patch (before Phase 0c) and
survived because the relibc code paths were never
exercised at runtime.
Kernel
Redox OS Microkernel
Requirements
nasmneeds to be available on the PATH at build time.
Building The Documentation
Use this command:
cargo doc --open --target x86_64-unknown-none
Debugging
QEMU
Running QEMU with the -s flag will set up QEMU to listen on port 1234 for a GDB client to connect to it. To debug the redox kernel run.
make qemu gdb=yes
This will start a virtual machine with and listen on port 1234 for a GDB or LLDB client.
GDB
If you are going to use GDB, run these commands to load debug symbols and connect to your running kernel:
(gdb) symbol-file build/kernel.sym
(gdb) target remote localhost:1234
LLDB
If you are going to use LLDB, run these commands to start debugging:
(lldb) target create -s build/kernel.sym build/kernel
(lldb) gdb-remote localhost:1234
After connecting to your kernel you can set some interesting breakpoints and continue
the process. See your debuggers man page for more information on useful commands to run.
Notes
-
Always use
foo.get(n)instead offoo[n]and try to cover for the possibility ofOption::None. Doing the regular way may work fine for applications, but never in the kernel. No possible panics should ever exist in kernel space, because then the whole OS would just stop working. -
If you receive a kernel panic in QEMU, use
pkill qemu-systemto kill the frozen QEMU process.
How To Contribute
To learn how to contribute to this system component you need to read the following document:
Development
To learn how to do development with this system component inside the Redox build system you need to read the Build System and Coding and Building pages.
How To Build
To build this system component you need to download the Redox build system, you can learn how to do it on the Building Redox page.
This is necessary because they only work with cross-compilation to a Redox virtual machine, but you can do some testing from Linux.
Funding - Unix-style Signals and Process Management
This project is funded through NGI Zero Core, a fund established by NLnet with financial support from the European Commission's Next Generation Internet program. Learn more at the NLnet project page.
