in the ISR doesn't read the actual socket event register, but instead
reads garbage (usually 0xffffffff, but other times other things).
This totally violates the PCI spec, but happens rarely enough that a
workaround is in order. This adds one test when we have a real
interrupt to service (which is very rare), and doesn't affect the
usualy 'nothing to see here' case at all.
Problem reported by many, but sam@ gave me this workaround after
diagnosing the problem.
a lock's priority to a sleeping thread. When we panic, dump a stack
trace of the thread that is asleep if DDB is compiled into the kernel
just before calling panic(). This is much more informative and useful
for debugging than the current behavior of getting a page fault and not
having an easy way of determining which thread caused the original problem.
MFC after: 1 week
a race where data could come in before we clear the INFLUX flag, and get
skipped over by knote (and hence never be activated, though it should of
been)...
Found by: glebius & co.
Reviewed by: glebius
MFC after: 3 days
some systems were designed so that AML writes to various resources shared
with OS drivers, including the RTC, PIC, PCI, etc. These writes could
collide with writes by the OS and should never be performed. For now, we
print a message if such an access occurs, but do not block it. To block
the access, the tunable "debug.acpi.block_bad_io" can be set to 1. In the
future, we will flip the switch and this will become the default.
Information about this problem was found in Microsoft KB 283649. They
block IO accesses if the BIOS indicates via _OSI that it is Windows 2001
or higher. They always block accesses to the PIC, cascaded PIC, and ELCRs,
no matter how old the BIOS.
systems (blade servers). On most systems, this is implemented as an IO
write to the SMI port and the BIOS generates the actual reset.
PR: kern/94939
Submitted by: dodell@ixsystems.com
Reviewed by: jhb
MFC after: 3 weeks
foreign per-CPU pages in cpu_ipi_send() in order to get the module IDs
of the other CPUs can cause a page fault. If this happens when doing a
TLB shootdown while dealing with another page fault this causes a panic
due to the recursive page fault. As I don't spot other code that assumes
or requires that accessing foreign per-CPU pages must not page fault
solve this by adding a statically allocated (and therefore locked in the
kernel pages) array which establishes a FreeBSD CPU ID -> module ID
relation and use that in cpu_ipi_selected() (instead of statically
allocating the per-CPU pages which would just waste memory on say a dual
CPU machine as sun4u theoretically supports up to 128 CPUs or wasting
dTLB slots for the foreign per-CPU pages). [1]
- Fix a potential race in cpu_ipi_send(); as we don't serialize the access
to cpu_ipi_selected() between MI and MD use (only MI-MI and MD-MD) we
might catch the NACK bit caused by sending another IPI. Solve this by
checking the NACK bit in the contents of the interrupt dispatch status
reg read while interrupts were still turned off instead of reading that
reg anew after interrupts were turned on again. This is also what the
CPU docs suggest to do.
- Add a workaround for the SpitFire erratum #54 bug (affecting interrupt
dispatch). While public info regarding what this CPU bug actually causes
is not available testing shows that with the workaround in place it's
less likely to get a "couldn't send ipi" panic, it doesn't solve these
panics entirely though. [2]
Reported by: kris [1]
Some clue from: kmacy [1]
Info from: Linux, OpenSolaris [2]
Additional testing by: kris
MFC after: 3 days
Saab for helping to track this down. Fix a error with 32bit DMA size
calculation that seemed to be harmless. Add a few micro-optimizations while
I'm here.
generating a coredump as the result of a signal.
- Fix a bug where we could leak a Giant lock if vn_start_write() failed
in coredump().
Reported by: jmg (2)
mddestroy() only if the file is from a non-MPSAFE VFS.
- No longer unconditionally hold Giant in the md kthread for vnode-backed
kthreads.
- Improve the handling of the thread exit race when destroying an md
device.
and use that instead of testing fdidx against -1 to determine if it should
release Giant if Giant was locked due to the requested file residing on a
non-MPSAFE VFS.
Discussed with: jeff
get_cyclecount() as that results in a saner value and makes schedgraph
much happier on Alpha. (schedgraph doesn't handle the fact that the
counters are out of sync though)
as we have to call tick_init() before cninit() in order to provide the
low-level console drivers with a working DELAY() which in turn means we
cannot use panic() in tick_init().
- s,to high, too high, in the panic string
Inspired by: kmacy's sun4v changes
MFC after: 3 days
probably never fully applied to IPv6. Over time it has become more
stale, so replace it with something more up to date.
Reviewed by: ume
MFC after: 1 month
ipsec_copypkt(), as this is already handled by the call to M_MOVE_PKTHDR(),
which also knows how to correctly handle MAC m_tags. This corrects a panic
when running with MAC and KAME IPSEC.
PR: kern/94599
Submitted by: zhouyi zhou <zhouyi04 at ios dot cn>
Reviewed by: bz
MFC after: 3 days
arguments. The first one is never used (all callers pass in 0); the
second is sometimes used to pass in a struct timespec * which is used as
a timeout and never modified. Constify that argument so callers can pass
a const struct timespec * without jumping through hoops.
back to using the RSDT instead. ACPI-CA already follows this same strategy
as a workaround for yet another instance of brain-damaged BIOS writers.
PR: i386/93963
Submitted by: Masayuki FUKUI <fukui.FreeBSD@fanet.net>
now just make it clear station statistics (could read
a stat block and assign to caller can do partial changes)
Reviewed by: avatar (previous version)
MFC after: 1 week
acquiring Giant in kern_sendfile().
Guard against the forced reclamation of a vnode in kern_sendfile().
Discussed with: jeff
Reviewed by: tegge
MFC after: 3 weeks
ipxpcb mutex. Contrary to the comment, even in 4.x this was unsafe,
as parallel use of the socket by another process would result in pcb
corruption if the mbuf allocation slept.
MFC after: 1 month
a problem with listing large number of md(4) devices. Either 'list' or
'query' mode uses XML.
Additionally, new functionality was introduced. It's possible to pass
multiple devices to -u:
# ./mdconfig -l -u md0,md1
Approved by: cognet (mentor)
REGRESSION is enabled, allows user space to dictate that sonewconn()
should skip it's "skip the hard work" check to see if the listen
queue is full, and instead proceed with allocation of a socket and
trimming of the overflowed queue. This makes it easier to test the
queue overflow logic.
MFC after: 1 month
