The combination of sd_netlink_message_enter_container() and
sd_netlink_message_read_string() only reads the last element if the attribute is
duplicated, such a situation easily happens for IFLA_ALT_IFNAME.
The function introduced here reads all matched attributes.
Let's just accept that the kernel is returning inconsistent results.
It seems to happen two only two variables on my machine:
/sys/firmware/efi/efivars/LoaderTimeInitUSec-4a67b082-0a4c-41cf-b6c7-440b29bb8c4f
/sys/firmware/efi/efivars/LoaderTimeMenuUSec-4a67b082-0a4c-41cf-b6c7-440b29bb8c4f
so it might be related to the way we write them.
If we call LOOP_CLR_FD and LOOP_CTL_REMOVE too rapidly, the kernel cannot deal
with that (5.3.13-300.fc31.x86_64 running on dual core
Intel(R) Core(TM) i7-6500U CPU @ 2.50GHz).
$ sudo strace -eioctl build/test-dissect-image /tmp/foobar3.img
ioctl(3, TCGETS, 0x7ffcee47de20) = -1 ENOTTY (Inappropriate ioctl for device)
ioctl(4, LOOP_CTL_GET_FREE) = 9
ioctl(5, LOOP_SET_FD, 3) = 0
ioctl(5, LOOP_SET_STATUS64, {lo_offset=0, lo_number=0, lo_flags=LO_FLAGS_READ_ONLY|LO_FLAGS_AUTOCLEAR|LO_FLAGS_PARTSCAN, lo_file_name="", ...}) = 0
ioctl(5, BLKGETSIZE64, [299999744]) = 0
ioctl(5, CDROM_GET_CAPABILITY, 0) = -1 EINVAL (Invalid argument)
ioctl(5, BLKSSZGET, [512]) = 0
Waiting for device (parent + 0 partitions) to appear...
Found root partition, writable of type btrfs at #-1 (/dev/block/7:9)
ioctl(5, LOOP_CLR_FD) = 0
ioctl(3, LOOP_CTL_REMOVE, 9) = -1 EBUSY (Device or resource busy)
Failed to remove loop device: Device or resource busy
This seems to be clear race condition, and attaching strace is generally enough
to "win" the race. But even with strace attached, we will fail occasionally.
Let's wait a bit and retry. With the wait, on my machine, the second attempt
always succeeds:
...
Found root partition, writable of type btrfs at #-1 (/dev/block/7:9)
ioctl(5, LOOP_CLR_FD) = 0
ioctl(3, LOOP_CTL_REMOVE, 9) = -1 EBUSY (Device or resource busy)
ioctl(3, LOOP_CTL_REMOVE, 9) = 9
+++ exited with 0 +++
Without the wait, all 64 attempts will occasionally fail.
shared/loop-util: fix error handling in loop_device_make_full()
The function no longer returns the fd. This complicated semantics, because it
wasn't clear what holds the ownership: the return value or the output
parameter. There were no users of the fd in the return value, so let's
simplify things conceptually and only return the fd once.
Reduce the scope of variables.
LOOP_CLR_FD was called on the wrong fd. Let's use a cleanup function to make
this automatic and reduce chances of a mixup in the future.
This makes --overlay=+/foobar::/foobar work again, i.e. where the middle
parameter is left out. According to the documentation this is supposed
to generate a temporary writable work place in the midle. But it
apparently never did. Weird.
docs: make sure there's only one # markdown header in each file
@bertob wants us to be strict here, and only have one "#" header per
markdown file, and use "##" (or "###", …) for all others. Interestingly,
we mostly got this right already, but this fixes a few cases where this
wasn't correct.
docs: direct to systemd.io version of naming scheme docs
The document was imported back in f9e6d49904e06d2cba3871f6873d0519fe086d0f. Let's make sure we actually
point to that version rather than the old one on freedesktop.
Let's use the rough categorization of the markdown pages to add basic
sections, via Jeykll templating. Also, add in a couple of additional
links via a JSON array that lists them.
AJ Bagwell [Tue, 10 Dec 2019 16:27:31 +0000 (16:27 +0000)]
ipv4ll: do not reset conflict counter on restart
Don't reset the conflict counter when trying a new pseudo random
address, so that after trying 10 addresses the londer timeout is used in
accordance with the RFC
strv: when growing strv arrays piecemeal actually allocate memory in exponential steps
Let's improve memory allocation for call such as strv_extend() that just
one item to an strv: these are often called in a loop, where they used
to be very ineffecient, since we'd allocate byte-exact space. With this
change let's improve on that, by allocating exponentially by rounding up
to the next exponent of 2. This way we get GREEDY_REALLOC()-like
behaviour without passing around state.
In fact this should be good enough so that we could replace existing
loops around GREEDY_REALLOC() for strv build-up with plain strv_extend()
and get similar behaviour.
The Intermediate Functional Block (ifb) pseudo network interface acts as a QoS concentrator for multiple different sources of traffic. Packets from or to other interfaces have to be redirected to it using the mirred action in order to be handled, regularly routed traffic will be dropped. This way, a single stack of qdiscs, classes and filters can be shared between multiple interfaces.
Here's a simple example to feed incoming traffic from multiple interfaces through a Stochastic Fairness Queue (sfq):
(1) # modprobe ifb
(2) # ip link set ifb0 up
(3) # tc qdisc add dev ifb0 root sfq
projects / thirdparty / systemd.git / log
