Before this commit, the save-entropy script rotates entropy files
like logs. This involves creating a new file that holds the entropy
and renaming of all existing entropy files. However, the entropy
data do not really need to be kept in a particular order, and
replacing the oldest file is sufficient.
This commit replaces the rotation with a scan in the
[1..entropy_save_num] space that finds the first empty slot, or
the slot of the oldest file, and writes entropy into that slot.
This also fixes an issue that prevents save-entropy from saving
any entropy when there is one non-regular file in any slot as a
side effect.
Based on an earlier patch from peterj@.
PR: 134225
Reported by: peterj
Reviewed by: csprng (cem, markm)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22612
The previously used quiesce_all_cpus walks all CPUs and waits until curthread
can run on them. Even on contemporary machines this becomes a significant
problem under load when it can literally take minutes for the operation to
complete. With the patch the stall is normally less than 1 second.
Reviewed by: kib, jeff (previous version)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21740
A variant of this facility was already used by rmlocks where IPIs would
enforce ordering.
This allows to elide fences where they are rarely needed and the cost of
IPI (should it be necessary) is cheaper.
Reviewed by: kib, jeff (previous version)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21740
This allows bumping threadcount without taking the global devmtx lock.
In particular this eliminates contention on said lock while using bhyve
with multiple vms.
Reviewed by: kib
Tested by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D22548
The former is frequently accessed (e.g., in vfs_cache_lookup) and shares the
cacheline with v_usecount, avoidably adding to cache misses during concurrent
lookup. The latter is almost unused and probably can get garbage-collected.
The struct does not change in size despite enum vs char * discrepancy.
On 64-bit archs there used to be 4 bytes padding after v_type giving 480 bytes
in total.
Just as disks can have nested partitions, the same happens with cd devices,
so we need to detect device paths and make sure we will not mix the handles.
To address this:
we fetch handle array and create linked list of block devices.
we walk the list and detect parent devices and set children pd_parent.
for {fd, cd, hd}, we walk device list and pick up our devices and store to
corresponding list. We make sure we store parent device first.
For sorting we use 3 steps: We check for floppy, we check for cd and then
everything else must be hd.
In general, it seems the floppy devices have no parent.
CD can have both parents and children (multiple boot entries, partitions
from the hybrid disk image).
Tested by: cross+freebsd@distal.com on Cisco UCS systems, C200 series (C220M5, C240M4).
Also on MBP with UEFI 1.10
Reported by: Chriss Ross
MFC after: 1w
Differential Revision: https://reviews.freebsd.org/D22553
broken in r355082. Reduce some locking in nearby related object type
checks.
Reviewed by: kib, markj
Differential Revision: https://reviews.freebsd.org/D22565
unset until the object is recycled so this check is stable. Now that we
can acquire the ref without a lock it is not necessary to group these
operations and we can avoid it entirely in many cases.
Reviewed by: kib, markj
Differential Revision: https://reviews.freebsd.org/D22565
in ofw_gpiobus_probe() return BUS_PROBE_DEFAULT rather than 0; we are not
the only possible driver to handle this device, we're just slightly better
than the base gpiobus (which probes at BUS_PROBE_GENERIC).
In the time since this code was first written, the gpio controller bindings
aquired the concept of a "hog" node which could be used to preset one or
more gpio pins as input or output at a specified level. This change doesn't
fully implement the hogging concept, it just filters out hog nodes when
instantiating child devices by scanning for child nodes in the fdt data.
The whole concept of having child nodes under the controller node is not
supported by the standard bindings, and appears to be a freebsd extension,
probably left over from the days when we had no support for cross-tree
phandle references in the fdt data.
Remove the duplicate macros that defined a subset of the VM_MEMATTR values.
While here use VM_MEMATTR macros when filling in the MAIR register.
Reviewed by: alc, markj
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22241
We already assert the lock is held later during tty_rel_free(), but it is
arguably good form to clarify locking expectations here as well at the
top-level that other drivers use.
vn_open_cred() assumes that it is called from the top-level of a VFS
syscall. Writers must call bwillwrite() before locking any VFS
resource to wait for cleanup of dirty buffers.
ZFS getextattr() and setextattr() VOPs do call vn_open_cred(), which
results in wait for unrelated buffers while owning ZFS vnode lock (and
ZFS does not use buffer cache). VN_OPEN_INVFS allows caller to skip
bwillwrite.
Note that ZFS is still incorrect there, because it starts write on an
mp and locks a vnode while holding another vnode lock.
Reported by: Willem Jan Withagen <wjw@digiware.nl>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
We might race with reclaim, and then this is no longer a nfs vnode, in
which case we do not need to handle deferred vnode_pager_setsize()
either.
Reported by: rk@ronald.org
PR: 242184
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Since version 2.11.0, QEMU became bug-compatible with
PowerVM's vty implementation, by inserting a \0 after
every \r going to the guest. Guests are expected to
workaround this issue by removing every \0 immediately
following a \r.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22171
The use of the uma trash procedures is automatic, there's no need to
pass them explicitly here.
Reviewed by: markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D22582
tty_pts.c relies on sys/tty.h for sys/mutex.h. Include it directly instead
of relying on this pollution to ease the diff for anyone that wants to try
converting the tty lock to anything other than a mutex.
The previous revision missed the exact same error in a copy paste block
of the same code in another function. Fix the identical case, too.
A DHCP client identifier is simply the hardware type (one byte)
concatenated with the hardware address (some variable number of bytes,
but at most 16). Limit the size of the temporary buffer to match and
the rest of the calculations shake out correctly.
PR: 238022
Reported by: Young <yangx92 AT hotmail.com>
Submitted by: Young <yangx92 AT hotmail.com>
MFC after: I don't plan to but you should feel free
Security: yes
(e.g. root->left = NULL) to affect the behavior of that function. This
change stops that data manipulation, and instead calls a pair of
functions, one for the left direction and the other for the right,
with the function called depending whether or not we currently null
the root child in that direction to control the behavior of
vm_map_splay_merge.
Reviewed by: kib
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22589
A crash was reported where the nr_client field was NULL during an upcall
to the nfsuserd daemon. Since nr_client == NULL only occurs when the
nfsuserd daemon is being shut down, it appeared to be caused by a race
between doing an upcall and the daemon shutting down.
By inspection two races were identified:
1 - The nfsrv_nfsuserd variable is used to indicate whether or not the
daemon is running. However it did not handle the intermediate phase
where the daemon is starting or stopping.
This was fixed by making nfsrv_nfsuserd tri-state and having the
functions that are called during start/stop to obey the intermediate
state.
2 - nfsrv_nfsuserd was checked to see that the daemon was running at
the beginning of an upcall, but nothing prevented the daemon from
being shut down while an upcall was still in progress.
This race probably caused the crash.
The patch fixes this by adding a count of upcalls in progress and
having the shut down function delay until this count goes to zero
before getting rid of nr_client and related data used by an upcall.
Tested by: avg (Panzura QA)
Reported by: avg
Reviewed by: avg
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22377
In case L2ARC read failed, l2arc_read_done() creates _different_ ZIO
to read data from the original storage device. Unfortunately pointer
to the failed ZIO remains in hdr->b_l1hdr.b_acb->acb_zio_head, and if
some other read try to bump the ZIO priority, it will crash.
The problem is reproducible by corrupting L2ARC content and reading
some data with prefetch if l2arc_noprefetch tunable is changed to 0.
With the default setting the issue is probably not reproducible now.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
as requiresd by the socket API specification.
Thanks to Inaki Baz Castillo, who found this bug running the userland
stack with valgrind and reported the issue in
https://github.com/sctplab/usrsctp/issues/408
MFC after: 1 week
union members in vm_page.h to store the zone and slab. Remove some nearby
dead code.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D22564
RB_MULTIPLE without RB_SERIAL set is valid, and means 'Video first, then serial'
to the kernel (so kernel messages go to both, but /etc/rc uses video console
(this should be fixed, btw, but another day)). Check for RB_MULTIPLE as well as
RB_SERIAL where we want to to serial things. This means we'll use the old code
for emulation in these situations, which is likely best since we're outputing to
both and the old code is ligher weight allowing both to keep up w/o weird
scrolling things.
I have no good explanation why it happens, but I found that in B2B mode
at least Xeon v4 NTB leaks accesses to its configuration memory at BAR0
originated from the link side to its host side. DMAR predictably blocks
those, making access to remote scratchpad registers in B2B mode impossible.
This change creates identity mapping in DMAR covering the BAR0 addresses,
making the NTB work fine with DMAR enabled. It seems like allowing single
4KB range at 32KB offset may be enough, but I don't see a reason to be so
specific.
MFC after: 1 week
Sponsored by: iXsystems, Inc.
