Such situation is defined as UNPREDICTABLE by arm arm manual.
This patch fixes all explicit TLB fetches which could cause this issue
and speculative TLB fetches for sections mapped in user address space.
Speculative TLB fetches for sections mapped in kernel address space are
not fixed yet as the break-before-make approach must be implemented for
kernel mappings too. This means that promoted/demoted section will be
unmapped for a while. Either kernel stack the promotion/demotion is
being done on or L1 page table(s) which must be modified may be mapped
by this section. Thus the fix will not be so simple like for userland
mappings.
The issue was detectable only on Cortex-A8 platforms and only very
rarely. It was reported few times. First, it was by Mikael Urankar
in June 2015. He helped to identify the mechanism of this issue, but
we were not sure how to fix it correctly until now.
PR: 208381
Reported by: Mikael Urankar (mikael.urankar at gmail.com)
Reviewed by: kib
This fixes a kernel panic when using IPoIB with VIMAGE and infiniband.
PR: 208957
Sponsored by: Mellanox Technologies
Tested by: Justin Clift <justin@postgresql.org>
MFC after: 1 week
and R/W emulation aborts under pmap lock.
There were two reasons for using of atomic operations:
(1) the pmap code is based on i386 one where they are used,
(2) there was an idea that access and R/W emulation aborts should be
handled as quick as possible, without pmap locking.
However, the atomic operations in i386 pmap code are used only because
page table entries may be modified by hardware. At the beginning, we
were not sure that it's the only reason. So even if arm hardware does
not modify them, we did not risk to not use them at that time. Further,
it turns out after some testing that using of pmap lock for access and
R/W emulation aborts does not bring any extra cost and there was no
measurable difference. Thus, we have decided finally to use pmap lock
for all operations on page table entries and so, there is no reason for
atomic operations on them. This makes the code cleaner and safer.
This decision introduce a question if it's safe to use pmap lock for
access and R/W emulation aborts. Anyhow, there may happen two cases in
general:
(A) Aborts while the pmap lock is locked already - this should not
happen as pmap lock is not recursive. However, under pmap lock only
internal kernel data should be accessed and such data should be mapped
with A bit set and NM bit cleared. If double abort happens, then
a mapping of data which has caused it must be fixed.
(B) Aborts while another lock(s) is/are locked - this already can
happen. There is no difference here if it's either access or R/W
emulation abort, or if it's some other abort.
Reviewed by: kib
(PL1) and unprivileged (PL0) read/write access. As cp15 virtual to
physical address translation operations are used, interrupts must be
disabled to get consistent result when they are called.
These functions should be used only in very specific occasions like
during abort handling or kernel debugging. One of them is going to be
used in pmap_fault(). However, complete function set is added. It cost
nothing, as they are inlined.
While here, fix comment of #endif.
Reviewed by: kib
- xalloc(..) ensures that e will be non-null via malloc + err.
- `e` is already dereferenced above, so logically it's impossible
to hit the lower test without crashing if it was indeed NULL.
MFC after: 3 days
CID: 1007408
Reported by: Coverity
Sponsored by: EMC / Isilon Storage Division
Submitted by: Jun Su <junsu microsoft com>
Reviewed by: sephe, Dexuan Cui <decui microsoft com>
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D5957
Pass dwarf-version to cc1as.
Fix PR26999 - crashing in cc1as with any '*bsd' target.
This should fix possible crashes when using -g in combination with
-save-temps.
Replace loop with switch statement (rate2ridx())
(should be noop).
Tested with RTL8188EU / RTL8188CUS, STA mode.
Reviewed by: adrian
Differential Revision: https://reviews.freebsd.org/D4848 (rebased)
rounddown2 tends to produce longer lines than the original code
and when the code has a high indentation level it was not really
advantageous to do the replacement.
This tries to strike a balance between readability using the macros
and flexibility of having the expressions, so not everything is
converted.
bcm2835_mbox_fb_init sets configuration so SET_VIRTUAL_OFFSET should be used
instead of GET_VIRTUAL_OFFSET
Submitted by: Sylvain Garrigues <sylvain@sylvaingarrigues.com>
- Enable the commented out locking in fd_probe(). The worker thread
should not be running yet (even after these changes), but better to be
safe than sorry.
- Defer starting the worker thread until after the child drives have been
probed. The worker thread startup is moved into a fdc_start_worker()
thread that the various front ends call at the end of attach. As a
side effect this fixes a few edge cases that weren't shutting down the
worker thread if attach encountered a late failure.
- When executing the initial reset requested by attach in the worker
thread, use DELAY() instead of a tsleep() if cold is set.
Tested by: Howard Su <howard0su@gmail.com>
Sponsored by: Netflix
Eventually with earlier AP startup this code will change to call the
startup function synchronously instead of queueing the task. Moving
the time we queue the task should be a no-op since taskqueue threads
don't start executing tasks until much later, but this reduces the diff
with the earlier AP startup patches.
Sponsored by: Netflix
sys/geom/geom_disk.c:
disk_attr_changed(): Generate a devctl event of type GEOM:<attr> for
every call.
MFC after: 4 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D5952
IPv6 addresses has a scope ID which sometimes is stored in the
"sin6_scope_id" field of "struct sockaddr_in6" and sometimes as part
of the IPv6 address itself depending on the context. If the scope ID
is not in the expected location, the IPv6 address lookups in the
so-called GID table will fail. Some code factoring has been made to
achieve a clean exit of the "addr_resolve" function via a common
"done" label.
Sponsored by: Mellanox Technologies
Submitted by: Shani Michaeli <shanim@mellanox.com>
MFC after: 1 week
This also protects them from trying to create .meta files
with WITH_META_MODE.
Reported by: Nikolai Lifanov <lifanov@mail.lifanov.com>
Sponsored by: EMC / Isilon Storage Division
already required both of them, so having a separate rctl_lock didn't
buy us anything.
Reviewed by: mjg@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5914
tp->snd_wnd. This can happen, for example, when the remote side responds to
a window probe by ACKing the one byte it contains.
Differential Revision: https://reviews.freebsd.org/D5625
Reviewed by: hiren
Obtained from: Juniper Networks (earlier version)
MFC after: 2 weeks
Sponsored by: Juniper Networks
