here use the given 'flags' argument, and not M_DONTWAIT.
We have a problem with several drivers: they poll an mbuf chain from their
queues and call m_defrag on them, but m_defrag could update the mbuf
pointer, so the mbuf in the queue is no longer valid. It is not easy to
fix each driver, because doing pop+push will reorder the queue, and we
don't really want that to happen.
This problem was independently spotted by me, Kengo, Masanobu, and other
people too it seems (perhaps PR/53218).
Now m_defrag leaves the first mbuf in place, and compresses the chain
only starting from the second mbuf in the chain.
It is important not to compress the first mbuf with hacks, because the
storage of this first mbuf may be shared with other mbufs.
Replace traceme2 with 3 tests:
- traceme_sighandler_catch1
- traceme_sighandler_catch2
- traceme_sighandler_catch3
These tests are verified with PT_TRACE_ME for: SIGHUP, SIGCONT and SIGABRT.
We don't want tests all signals (this is a domain for a fuzzer), but we want
to cover tests with signals from different groups.
All tests pass.
Sponsored by <The NetBSD Foundation>
Use common bode for these tests and a macro 1-liner to define a new test.
Test the same scenarios for 5 signals:
- SIGKILL (temporarily disabled)
- SIGSTOP
- SIGABRT
- SIGHUP
- SIGCONT
These tests call: raise(sig). It's actually important to assert their
behavior for tests that are from different kinds.
The SIGKILL test is work in progress. It can be caught by a debugger on the
FreeBSD kernel, but it's causing a signaled event in a debugger on Linux.
NetBSD is right now in one of the camps, but research whether this is a bug
or feature is in progress.
Sponsored by <The NetBSD Foundation>
Also, simplify MEXTMALLOC, mbtypes[] doesn't exist anymore, but the code
still compiled correctly because "malloc" is a macro and the argument
was dropped.
The tunnel interfaces are gif(4), l2tp(4), and ipsecif(4). They use mutex
itself in percpu area. When percpu_cpu_enlarge() run, the address of the
mutex in percpu area becomes different from the address which lockdebug
saved. That can cause "already initialized" false detection.
M_ROMAP tells us whether the mbuf storage is mapped on a read-only page.
But an mbuf can still be read-only in the sense that the storage is
shared with other mbufs.
macro. Macros are inefficient when they contain too many instructions and
are used too often, because of cache coherency (and also register use).
This change saves 32KB of kernel .text.
riastradh