Mark Johnston
61a14ddfe0
Running the test suite yields: lock order reversal: 1st 0xfffff80004bc6700 unp (unp, sleep mutex) @ sys/kern/uipc_usrreq.c:390 2nd 0xffffffff81a94b30 unp_link_rwlock (unp_link_rwlock, rw) @ sys/kern/uipc_usrreq.c:2934 lock order unp -> unp_link_rwlock attempted at: 0xffffffff80bc216e at witness_checkorder+0xbbe 0xffffffff80b493a5 at _rw_wlock_cookie+0x65 0xffffffff80c0a8e2 at unp_discard+0x22 0xffffffff80c0a888 at unp_freerights+0x38 0xffffffff80c09fdd at unp_scan+0x9d 0xffffffff80c0f9a7 at uipc_sosend_dgram+0x727 0xffffffff80c00a79 at sousrsend+0x79 0xffffffff80c072d0 at kern_sendit+0x1c0 0xffffffff80c074d7 at sendit+0xb7 0xffffffff80c076f3 at sys_sendmsg+0x63 0xffffffff8104d957 at amd64_syscall+0x6b7 0xffffffff8101f9eb at fast_syscall_common+0xf8 This happens when uipc_sosend_dgram() discards a control message because the receive socket buffer is full. The overflow handling frees internalized file references in the socket buffer before freeing mbufs. It does this with socket PCBs locked, leading to the LOR. Defer handling of file references until the PCBs are unlocked. Reviewed by: glebius MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D41884
FreeBSD Kernel Source:
This directory contains the source files and build glue that make up the FreeBSD kernel and its modules, including both original and contributed software.
Kernel configuration files are located in the conf/ subdirectory of each
architecture. GENERIC is the configuration used in release builds. NOTES
contains documentation of all possible entries. LINT is a compile-only
configuration used to maximize build coverage and detect regressions.
Documentation:
Source code documentation is maintained in a set of man pages, under section 9.
These pages are located in share/man/man9, from the
top-level of the src tree. Consult intro(9)
for an overview of existing pages.
Some additional high-level documentation of the kernel is maintained in the Architecture Handbook.
Source Roadmap:
| Directory | Description |
|---|---|
| amd64 | AMD64 (64-bit x86) architecture support |
| arm | 32-bit ARM architecture support |
| arm64 | 64-bit ARM (AArch64) architecture support |
| cam | Common Access Method storage subsystem - cam(4) and ctl(4) |
| cddl | CDDL-licensed optional sources such as DTrace |
| conf | kernel build glue |
| compat | Linux compatibility layer, FreeBSD 32-bit compatibility |
| contrib | 3rd-party imported software such as OpenZFS |
| crypto | crypto drivers |
| ddb | interactive kernel debugger - ddb(4) |
| fs | most filesystems, excluding UFS, NFS, and ZFS |
| dev | device drivers and other arch independent code |
| gdb | kernel remote GDB stub - gdb(4) |
| geom | GEOM framework - geom(4) |
| i386 | i386 (32-bit x86) architecture support |
| kern | main part of the kernel |
| libkern | libc-like and other support functions for kernel use |
| modules | kernel module infrastructure |
| net | core networking code |
| net80211 | wireless networking (IEEE 802.11) - net80211(4) |
| netgraph | graph-based networking subsystem - netgraph(4) |
| netinet | IPv4 protocol implementation - inet(4) |
| netinet6 | IPv6 protocol implementation - inet6(4) |
| netipsec | IPsec protocol implementation - ipsec(4) |
| netpfil | packet filters - ipfw(4), pf(4), and ipfilter(4) |
| opencrypto | OpenCrypto framework - crypto(7) |
| powerpc | PowerPC/POWER (32 and 64-bit) architecture support |
| riscv | 64-bit RISC-V architecture support |
| security | security facilities - audit(4) and mac(4) |
| sys | kernel headers |
| tests | kernel unit tests |
| ufs | Unix File System - ffs(7) |
| vm | virtual memory system |
| x86 | code shared by AMD64 and i386 architectures |