A weakness of the page->mlock_count approach is the need for lruvec lock
while holding page table lock. That is not an overhead we would allow on
normal pages, but I think acceptable just for pages in an mlocked area.
But let's try to amortize the extra cost by gathering on per-cpu pagevec
before acquiring the lruvec lock.
I have an unverified conjecture that the mlock pagevec might work out
well for delaying the mlock processing of new file pages until they have
got off lru_cache_add()'s pagevec and on to LRU.
The initialization of page->mlock_count is subject to races and awkward:
0 or !!PageMlocked or 1? Was it wrong even in the implementation before
this commit, which just widens the window? I haven't gone back to think
it through. Maybe someone can point out a better way to initialize it.
Bringing lru_cache_add_inactive_or_unevictable()'s mlock initialization
into mm/mlock.c has helped: mlock_new_page(), using the mlock pagevec,
rather than lru_cache_add()'s pagevec.
Experimented with various orderings: the right thing seems to be for
mlock_page() and mlock_new_page() to TestSetPageMlocked before adding to
pagevec, but munlock_page() to leave TestClearPageMlocked to the later
pagevec processing.
Dropped the VM_BUG_ON_PAGE(PageTail)s this time around: they have made
their point, and the thp_nr_page()s already contain a VM_BUG_ON_PGFLAGS()
for that.
This still leaves acquiring lruvec locks under page table lock each time
the pagevec fills (or a THP is added): which I suppose is rather silly,
since they sit on pagevec waiting to be processed long after page table
lock has been dropped; but I'm disinclined to uglify the calling sequence
until some load shows an actual problem with it (nothing wrong with
taking lruvec lock under page table lock, just "nicer" to do it less).
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Oded Gabbay reports that enabling NUMA balancing causes corruption with
his Gaudi accelerator test load:
"All the details are in the bug, but the bottom line is that somehow,
this patch causes corruption when the numa balancing feature is
enabled AND we don't use process affinity AND we use GUP to pin pages
so our accelerator can DMA to/from system memory.
Either disabling numa balancing, using process affinity to bind to
specific numa-node or reverting this patch causes the bug to
disappear"
and Oded bisected the issue to commit 09854ba94c ("mm: do_wp_page()
simplification").
Now, the NUMA balancing shouldn't actually be changing the writability
of a page, and as such shouldn't matter for COW. But it appears it
does. Suspicious.
However, regardless of that, the condition for enabling NUMA faults in
change_pte_range() is nonsensical. It uses "page_mapcount(page)" to
decide if a COW page should be NUMA-protected or not, and that makes
absolutely no sense.
The number of mappings a page has is irrelevant: not only does GUP get a
reference to a page as in Oded's case, but the other mappings migth be
paged out and the only reference to them would be in the page count.
Since we should never try to NUMA-balance a page that we can't move
anyway due to other references, just fix the code to use 'page_count()'.
Oded confirms that that fixes his issue.
Now, this does imply that something in NUMA balancing ends up changing
page protections (other than the obvious one of making the page
inaccessible to get the NUMA faulting information). Otherwise the COW
simplification wouldn't matter - since doing the GUP on the page would
make sure it's writable.
The cause of that permission change would be good to figure out too,
since it clearly results in spurious COW events - but fixing the
nonsensical test that just happened to work before is obviously the
CorrectThing(tm) to do regardless.
Fixes: 09854ba94c ("mm: do_wp_page() simplification")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215616
Link: https://lore.kernel.org/all/CAFCwf10eNmwq2wD71xjUhqkvv5+_pJMR1nPug2RqNDcFT4H86Q@mail.gmail.com/
Reported-and-tested-by: Oded Gabbay <oded.gabbay@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
My reading of comment on smp_mb__after_atomic() in __pagevec_lru_add_fn()
says that it can now be deleted; and that remains so when the next patch
is added.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Compaction, NUMA page movement, THP collapse/split, and memory failure
do isolate unevictable pages from their "LRU", losing the record of
mlock_count in doing so (isolators are likely to use page->lru for their
own private lists, so mlock_count has to be presumed lost).
That's unfortunate, and we should put in some work to correct that: one
can imagine a function to build up the mlock_count again - but it would
require i_mmap_rwsem for read, so be careful where it's called. Or
page_referenced_one() and try_to_unmap_one() might do that extra work.
But one place that can very easily be improved is page migration's
__unmap_and_move(): a small adjustment to where the successful new page
is put back on LRU, and its mlock_count (if any) is built back up by
remove_migration_ptes().
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Fill in missing pieces: reimplementation of munlock_vma_pages_range(),
required to lower the mlock_counts when munlocking without munmapping;
and its complement, implementation of mlock_vma_pages_range(), required
to raise the mlock_counts on pages already there when a range is mlocked.
Combine them into just the one function mlock_vma_pages_range(), using
walk_page_range() to run mlock_pte_range(). This approach fixes the
"Very slow unlockall()" of unpopulated PROT_NONE areas, reported in
https://lore.kernel.org/linux-mm/70885d37-62b7-748b-29df-9e94f3291736@gmail.com/
Munlock clears VM_LOCKED at the start, under exclusive mmap_lock; but if
a racing truncate or holepunch (depending on i_mmap_rwsem) gets to the
pte first, it will not try to munlock the page: leaving release_pages()
to correct it when the last reference to the page is gone - that's okay,
a page is not evictable anyway while it is held by an extra reference.
Mlock sets VM_LOCKED at the start, under exclusive mmap_lock; but if
a racing remove_migration_pte() or try_to_unmap_one() (depending on
i_mmap_rwsem) gets to the pte first, it will try to mlock the page,
then mlock_pte_range() mlock it a second time. This is harder to
reproduce, but a more serious race because it could leave the page
unevictable indefinitely though the area is munlocked afterwards.
Guard against it by setting the (inappropriate) VM_IO flag,
and modifying mlock_vma_page() to decline such vmas.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Previous patches have been preparatory: now implement page->mlock_count.
The ordering of the "Unevictable LRU" is of no significance, and there is
no point holding unevictable pages on a list: place page->mlock_count to
overlay page->lru.prev (since page->lru.next is overlaid by compound_head,
which needs to be even so as not to satisfy PageTail - though 2 could be
added instead of 1 for each mlock, if that's ever an improvement).
But it's only safe to rely on or modify page->mlock_count while lruvec
lock is held and page is on unevictable "LRU" - we can save lots of edits
by continuing to pretend that there's an imaginary LRU here (there is an
unevictable count which still needs to be maintained, but not a list).
The mlock_count technique suffers from an unreliability much like with
page_mlock(): while someone else has the page off LRU, not much can
be done. As before, err on the safe side (behave as if mlock_count 0),
and let try_to_unlock_one() move the page to unevictable if reclaim finds
out later on - a few misplaced pages don't matter, what we want to avoid
is imbalancing reclaim by flooding evictable lists with unevictable pages.
I am not a fan of "if (!isolate_lru_page(page)) putback_lru_page(page);":
if we have taken lruvec lock to get the page off its present list, then
we save everyone trouble (and however many extra atomic ops) by putting
it on its destination list immediately.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Placing munlock_vma_page() at the end of page_remove_rmap() shifts most
of the munlocking to clear_page_mlock(), since PageMlocked is typically
still set when mapcount has fallen to 0. That is not what we want: we
want /proc/vmstat's unevictable_pgs_cleared to remain as a useful check
on the integrity of of the mlock/munlock protocol - small numbers are
not surprising, but big numbers mean the protocol is not working.
That could be easily fixed by placing munlock_vma_page() at the start of
page_remove_rmap(); but later in the series we shall want to batch the
munlocking, and that too would tend to leave PageMlocked still set at
the point when it is checked.
So delete clear_page_mlock() now: leave it instead to release_pages()
(and __page_cache_release()) to do this backstop clearing of Mlocked,
when page refcount has fallen to 0. If a pinned page occasionally gets
counted as Mlocked and Unevictable until it is unpinned, that's okay.
A slightly regrettable side-effect of this change is that, since
release_pages() and __page_cache_release() may be called at interrupt
time, those places which update NR_MLOCK with interrupts enabled
had better use mod_zone_page_state() than __mod_zone_page_state()
(but holding the lruvec lock always has interrupts disabled).
This change, forcing Mlocked off when refcount 0 instead of earlier
when mapcount 0, is not fundamental: it can be reversed if performance
or something else is found to suffer; but this is the easiest way to
separate the stats - let's not complicate that without good reason.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Add vma argument to mlock_vma_page() and munlock_vma_page(), make them
inline functions which check (vma->vm_flags & VM_LOCKED) before calling
mlock_page() and munlock_page() in mm/mlock.c.
Add bool compound to mlock_vma_page() and munlock_vma_page(): this is
because we have understandable difficulty in accounting pte maps of THPs,
and if passed a PageHead page, mlock_page() and munlock_page() cannot
tell whether it's a pmd map to be counted or a pte map to be ignored.
Add vma arg to page_add_file_rmap() and page_remove_rmap(), like the
others, and use that to call mlock_vma_page() at the end of the page
adds, and munlock_vma_page() at the end of page_remove_rmap() (end or
beginning? unimportant, but end was easier for assertions in testing).
No page lock is required (although almost all adds happen to hold it):
delete the "Serialize with page migration" BUG_ON(!PageLocked(page))s.
Certainly page lock did serialize with page migration, but I'm having
difficulty explaining why that was ever important.
Mlock accounting on THPs has been hard to define, differed between anon
and file, involved PageDoubleMap in some places and not others, required
clear_page_mlock() at some points. Keep it simple now: just count the
pmds and ignore the ptes, there is no reason for ptes to undo pmd mlocks.
page_add_new_anon_rmap() callers unchanged: they have long been calling
lru_cache_add_inactive_or_unevictable(), which does its own VM_LOCKED
handling (it also checks for not VM_SPECIAL: I think that's overcautious,
and inconsistent with other checks, that mmap_region() already prevents
VM_LOCKED on VM_SPECIAL; but haven't quite convinced myself to change it).
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
munlock_vma_pages_range() will still be required, when munlocking but
not munmapping a set of pages; but when unmapping a pte, the mlock count
will be maintained in much the same way as it will be maintained when
mapping in the pte. Which removes the need for munlock_vma_pages_all()
on mlocked vmas when munmapping or exiting: eliminating the catastrophic
contention on i_mmap_rwsem, and the need for page lock on the pages.
There is still a need to update locked_vm accounting according to the
munmapped vmas when munmapping: do that in detach_vmas_to_be_unmapped().
exit_mmap() does not need locked_vm updates, so delete unlock_range().
And wasn't I the one who forbade the OOM reaper to attack mlocked vmas,
because of the uncertainty in blocking on all those page locks?
No fear of that now, so permit the OOM reaper on mlocked vmas.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
If counting page mlocks, we must not double-count: follow_page_pte() can
tell if a page has already been Mlocked or not, but cannot tell if a pte
has already been counted or not: that will have to be done when the pte
is mapped in (which lru_cache_add_inactive_or_unevictable() already tracks
for new anon pages, but there's no such tracking yet for others).
Delete all the FOLL_MLOCK code - faulting in the missing pages will do
all that is necessary, without special mlock_vma_page() calls from here.
But then FOLL_POPULATE turns out to serve no purpose - it was there so
that its absence would tell faultin_page() not to faultin page when
setting up VM_LOCKONFAULT areas; but if there's no special work needed
here for mlock, then there's no work at all here for VM_LOCKONFAULT.
Have I got that right? I've not looked into the history, but see that
FOLL_POPULATE goes back before VM_LOCKONFAULT: did it serve a different
purpose before? Ah, yes, it was used to skip the old stack guard page.
And is it intentional that COW is not broken on existing pages when
setting up a VM_LOCKONFAULT area? I can see that being argued either
way, and have no reason to disagree with current behaviour.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
We have recommended some applications to mlock their userspace, but that
turns out to be counter-productive: when many processes mlock the same
file, contention on rmap's i_mmap_rwsem can become intolerable at exit: it
is needed for write, to remove any vma mapping that file from rmap's tree;
but hogged for read by those with mlocks calling page_mlock() (formerly
known as try_to_munlock()) on *each* page mapped from the file (the
purpose being to find out whether another process has the page mlocked,
so therefore it should not be unmlocked yet).
Several optimizations have been made in the past: one is to skip
page_mlock() when mapcount tells that nothing else has this page
mapped; but that doesn't help at all when others do have it mapped.
This time around, I initially intended to add a preliminary search
of the rmap tree for overlapping VM_LOCKED ranges; but that gets
messy with locking order, when in doubt whether a page is actually
present; and risks adding even more contention on the i_mmap_rwsem.
A solution would be much easier, if only there were space in struct page
for an mlock_count... but actually, most of the time, there is space for
it - an mlocked page spends most of its life on an unevictable LRU, but
since 3.18 removed the scan_unevictable_pages sysctl, that "LRU" has
been redundant. Let's try to reuse its page->lru.
But leave that until a later patch: in this patch, clear the ground by
removing page_mlock(), and all the infrastructure that has gathered
around it - which mostly hinders understanding, and will make reviewing
new additions harder. Don't mind those old comments about THPs, they
date from before 4.5's refcounting rework: splitting is not a risk here.
Just keep a minimal version of munlock_vma_page(), as reminder of what it
should attend to (in particular, the odd way PGSTRANDED is counted out of
PGMUNLOCKED), and likewise a stub for munlock_vma_pages_range(). Move
unchanged __mlock_posix_error_return() out of the way, down to above its
caller: this series then makes no further change after mlock_fixup().
After this and each following commit, the kernel builds, boots and runs;
but with deficiencies which may show up in testing of mlock and munlock.
The system calls succeed or fail as before, and mlock remains effective
in preventing page reclaim; but meminfo's Unevictable and Mlocked amounts
may be shown too low after mlock, grow, then stay too high after munlock:
with previously mlocked pages remaining unevictable for too long, until
finally unmapped and freed and counts corrected. Normal service will be
resumed in "mm/munlock: mlock_pte_range() when mlocking or munlocking".
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
vsock_connect() expects that the socket could already be in the
TCP_ESTABLISHED state when the connecting task wakes up with a signal
pending. If this happens the socket will be in the connected table, and
it is not removed when the socket state is reset. In this situation it's
common for the process to retry connect(), and if the connection is
successful the socket will be added to the connected table a second
time, corrupting the list.
Prevent this by calling vsock_remove_connected() if a signal is received
while waiting for a connection. This is harmless if the socket is not in
the connected table, and if it is in the table then removing it will
prevent list corruption from a double add.
Note for backporting: this patch requires d5afa82c97 ("vsock: correct
removal of socket from the list"), which is in all current stable trees
except 4.9.y.
Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Signed-off-by: Seth Forshee <sforshee@digitalocean.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20220217141312.2297547-1-sforshee@digitalocean.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 3710e80952.
Since idm_base and nicpm_base are still optional resources not present
on all platforms, this breaks the driver for everything except Northstar
2 (which has both).
The same change was already reverted once with 755f5738ff ("net:
broadcom: fix a mistake about ioremap resource").
So let's do it again.
Fixes: 3710e80952 ("net: ethernet: bgmac: Use devm_platform_ioremap_resource_byname")
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
[florian: Added comments to explain the resources are optional]
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20220216184634.2032460-1-f.fainelli@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Before freeing the hash table in addrconf_exit_net(),
we need to make sure the work queue has completed,
or risk NULL dereference or UAF.
Thus, use cancel_delayed_work_sync() to enforce this.
We do not hold RTNL in addrconf_exit_net(), making this safe.
Fixes: 8805d13ff1 ("ipv6/addrconf: use one delayed work per netns")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220216182037.3742-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Akira says:
This series resolves issues listed below:
1. Some of chapter and section counts in Table of Contents (TOC) in
large PDF docs collide with chapter/section titles, e.g., Chapters 10,
11, 12, and 13 and Section 10.10 in userspace-api.pdf.
2. In docs of more than 99 pages, page counts in TOC are not aligned
properly when maxdepth >= 2 is specified in toctree, e.g., Chapters 10,
12, and 13 in userspace-api.pdf
3. In TOC of Latin-script docs, quotation and apostrophe symbols look too
wide, e.g., Section 2.2 in userspace-api.pdf.
4. In TOC of translations, Korean chapter titles lose inter-phrase spaces.
5. On systems without "Noto Sans CJK" fonts, CJK chapters in translations
results in full of "TOFU" boxes, with a long build time and a large
log file containing lots of missing-font warnings.
6. In translations.pdf built by "make pdfdocs", ascii-art diagrams in CJK
are not aligned properly.
At boot on the BCM2711, if the HDMI controllers are running, the CRTC
driver will disable itself and its associated HDMI controller to work
around a hardware bug that would leave some pixels stuck in a FIFO.
In order to avoid that issue, we need to run some operations in lockstep
between the CRTC and HDMI controller, and we need to make sure the HDMI
controller will be powered properly.
However, since we haven't enabled it through KMS, the runtime_pm state
is off at this point so we need to make sure the device is powered
through pm_runtime_resume_and_get, and once the operations are complete,
we call pm_runtime_put.
However, the HDMI controller will do that itself in its
post_crtc_powerdown, which means we'll end up calling pm_runtime_put for
a single pm_runtime_get, throwing the reference counting off. Let's
remove the pm_runtime_put call in the CRTC code in order to have the
proper counting.
Fixes: bca10db67b ("drm/vc4: crtc: Make sure the HDMI controller is powered when disabling")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220203102003.1114673-1-maxime@cerno.tech
On bind we will register the HDMI codec device but we don't unregister
it on unbind, leading to a device leakage. Unregister our device at
unbind.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220127111452.222002-1-maxime@cerno.tech
Sprinkle for each loops to allow netdevices to be unregistered
out of order, as their refs are released.
This prevents problems caused by dependencies between netdevs
which want to release references in their ->priv_destructor.
See commit d6ff94afd9 ("vlan: move dev_put into vlan_dev_uninit")
for example.
Eric has removed the only known ordering requirement in
commit c002496bab ("Merge branch 'ipv6-loopback'")
so let's try this and see if anything explodes...
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/20220215225310.3679266-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In prep for unregistering netdevs out of order move the netdev
state validation and change outside of the loop.
While at it modernize this code and use WARN() instead of
pr_err() + dump_stack().
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/20220215225310.3679266-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The qib driver load has been failing with the following message:
sysfs: cannot create duplicate filename '/devices/pci0000:80/0000:80:02.0/0000:81:00.0/infiniband/qib0/ports/1/linkcontrol'
The patch below has two "linkcontrol" names causing the duplication.
Fix by using the correct "diag_counters" name on the second instance.
Fixes: 4a7aaf88c8 ("RDMA/qib: Use attributes for the port sysfs")
Link: https://lore.kernel.org/r/1645106372-23004-1-git-send-email-mike.marciniszyn@cornelisnetworks.com
Cc: <stable@vger.kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
XRC INI QPs should be able to adjust their local ACK timeout.
Fixes: 2c1619edef ("IB/cma: Define option to set ack timeout and pack tos_set")
Link: https://lore.kernel.org/r/1644421175-31943-1-git-send-email-haakon.bugge@oracle.com
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Suggested-by: Avneesh Pant <avneesh.pant@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
After slave abort, all DMA should be stopped, or it will affect the
next transmission and maybe abort again.
Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
Link: https://lore.kernel.org/r/20220216014028.8123-3-jon.lin@rock-chips.com
Signed-off-by: Mark Brown <broonie@kernel.org>
With the existing logic where clear_ack is true (HW doesn’t support
auto clear for ICR), interrupt clear register reset is not handled
properly. Due to this only the first interrupts get processed properly
and further interrupts are blocked due to not resetting interrupt
clear register.
Example for issue case where Invert_ack is false and clear_ack is true:
Say Default ISR=0x00 & ICR=0x00 and ISR is triggered with 2
interrupts making ISR = 0x11.
Step 1: Say ISR is set 0x11 (store status_buff = ISR). ISR needs to
be cleared with the help of ICR once the Interrupt is processed.
Step 2: Write ICR = 0x11 (status_buff), this will clear the ISR to 0x00.
Step 3: Issue - In the existing code, ICR is written with ICR =
~(status_buff) i.e ICR = 0xEE -> This will block all the interrupts
from raising except for interrupts 0 and 4. So expectation here is to
reset ICR, which will unblock all the interrupts.
if (chip->clear_ack) {
if (chip->ack_invert && !ret)
........
else if (!ret)
ret = regmap_write(map, reg,
~data->status_buf[i]);
So writing 0 and 0xff (when ack_invert is true) should have no effect, other
than clearing the ACKs just set.
Fixes: 3a6f0fb7b8 ("regmap: irq: Add support to clear ack registers")
Signed-off-by: Prasad Kumpatla <quic_pkumpatl@quicinc.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20220217085007.30218-1-quic_pkumpatl@quicinc.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In order for the phy driver to be able to actually get and control
the cs and reset GPIOs the dev_id member of the gpiod_lookup table must
be set to point to the dev_name() of the ulpi-device instantiated by
dwc3_ulpi_init().
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220213130524.18748-6-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some Android x86 tablets with a Bay Trail (BYT) SoC and a Crystal Cove
PMIC, which does not support charger-detection, rely on the TUSB1211 phy
for charger-detection.
Windows tablets with the same SoC + PMIC often use an extra chip for
charger-detection like the FSA831A. But since on Android tablets
the designers already need to add a TUSB1211 phy to support device/gadget
mode the phy is used to do charger-detection instead.
These Android x86 tablets can be identified by the unique combination of
a Bay Trail SoC (already checked for by PCI-ids) + a Crystal Cove PMIC +
not using the standard ACPI battery and ac drivers. Where as on Windows
tablets the standard ACPI battery and ac drivers will be used on BYT
boards with a Crystal Cove PMIC.
Set a special kernel-internal (so not part of the dt-bindings)
"linux,phy_charger_detect" property on these boards, which tells the
tusb1210 driver to enable charger-detection.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220213130524.18748-5-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The quirk handling may need to set some different properties
which means using a different swnode, move the setting of the swnode
to inside dwc3_pci_quirks() so that the quirk handling can choose
a different swnode.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220213130524.18748-4-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
WUSB3801 features a configurable port type, accessory detection, and
plug orientation detection. It provides a hardware "ID" pin output for
compatibility with USB 2.0 OTG PHYs. Add a typec class driver for it.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20220214050118.61015-5-samuel@sholland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Basic programmable non-PD Type-C port controllers do not need the full
TCPM library, but they share the same devicetree binding and the same
typec_capability structure. Factor out a helper for parsing those
properties which map to fields in struct typec_capability, so the code
can be shared between TCPM and basic non-TCPM drivers.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20220214050118.61015-4-samuel@sholland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add devicetree support for the Will Semiconductor WUSB3801. This is a
basic non-PD Type-C port controller.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20220214050118.61015-3-samuel@sholland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In xhci_endpoint_{disable|reset}() the expression '&vdev->eps[ep_index]'
just cannot be NULL, so the checks have no sense at all...
Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-9-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Trying to disable Link Powermanagement (LPM) before port reset is
unnecessary and can cause additional delay if host can't communicate
with the device, which is often the reason why device is reset in the
first place.
usb_disable_lpm() will
- zero usb U1/U2 timeouts for the hub downstream port
- send ENABLE U1/U2 clear feature requests to the connected device.
- increase internal reference count for udev->lpm_disable_count
There is no need to zero U1/U2 hub port timeouts, or clearing the
U1/U2 enable for the connected device before reset. These are set
to default by the reset.
USB 3.1 section 10.2.2 "HUB Downstream port U1/U2 timers" states that:
"the U1 and U2 timeout values for a downstream port reset to the default
values when the port receives a SetPortFeature request for a port reset"
Set the udev->lpm_disable_count to "1" after port reset, which is the
default lpm_disable_count value when allocating udev, representing
disabled LPM.
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-8-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Every lpm commmand, both for USB 2 and USB 3 devies used the same
xhci->lpm_command structure to change max exit latency.
xhci->lpm_command is only protected by a hcd->bandwidth mutex, which is
not enoungh as USB 2 and USB 3 devices are behind separate HCDs.
Simplify code and avoid unnecessary locking risks by allocating
separate command structures for each lpm command, just like with
all other commands.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-7-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To support systems with several xhci controllers with active
dbc on each xhci we need to use IDR to identify and give
an index to each port.
Avoid using global struct tty_driver.driver_state for storing
dbc port pointer as it won't work with several dbc ports
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-6-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current workaround to call the dbc_tty_init() in probe is
not working in case we have several xhci devices with dbc enabled.
dbc_tty_init() should be called only once by a module init call when
module is loaded.
until dbgtty is its own module call dbc_tty_init() from xhci
module init call.
Same is true for unloading and dbc_tty_exit()
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-5-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These names give the impression the functions are related to
module init calls, but are in fact creating and removing the dbc
fake device
Rename them to xhci_create_dbc_dev() and xhci_remove_dbc_dev().
We will need the _init and _exit names for actual dbc module init
and exit calls.
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Turn the dbgtty closer to a device driver by allocating the dbc
structure in its own xhci_dbc_tty_probe() function, and freeing it
in xhci_dbc_tty_remove()
Remove xhci_do_dbc_exit() as its no longer needed.
allocate and create the dbc strcuture in xhci_dbc_tty_probe()
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Refactor xhci_dbc_init(), splitting it into logical
parts closer to the Linux device model.
- Create the fake dbc device, depends on xhci strucure
- Allocate a dbc structure, xhci agnostic
- Call xhci_dbc_tty_probe(), similar to actual probe.
Adjustments to xhci_dbc_exit and xhci_dbc_remove are also needed
as a result to the xhci_dbc_init() changes
Mostly non-functional changes, except for creating the dbc sysfs
entry earlier, together with the dbc structure.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220216095153.1303105-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The CONFIG_OF maybe set, but it may not be applicable to a device. In
such case, checking against that can cause the device fail to
initialize. Check against the device node (device->of_node) instead.
Fixes: a102f07e4e ("usb: dwc3: drd: Add support for usb-conn-gpio based usb-role-switch")
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/9f15580ad5810b1e5f31c241b35ebedfbfc30a3f.1644964864.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the custom functions xhci_mtk_ldos_{enable,disable}() by
switching to using regulator_bulk to perform the very same thing,
as the regulators are always either both enabled or both disabled.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220214111905.77903-1-angelogioacchino.delregno@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While examining is_ucounts_overlimit and reading the various messages
I realized that is_ucounts_overlimit fails to deal with counts that
may have wrapped.
Being wrapped should be a transitory state for counts and they should
never be wrapped for long, but it can happen so handle it.
Cc: stable@vger.kernel.org
Fixes: 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
Link: https://lkml.kernel.org/r/20220216155832.680775-5-ebiederm@xmission.com
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
During set*id() which cred->ucounts to charge the the current process
to is not known until after set_cred_ucounts. So move the
RLIMIT_NPROC checking into a new helper flag_nproc_exceeded and call
flag_nproc_exceeded after set_cred_ucounts.
This is very much an arbitrary subset of the places where we currently
change the RLIMIT_NPROC accounting, designed to preserve the existing
logic.
Fixing the existing logic will be the subject of another series of
changes.
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20220216155832.680775-4-ebiederm@xmission.com
Fixes: 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Michal Koutný <mkoutny@suse.com> wrote:
> Tasks are associated to multiple users at once. Historically and as per
> setrlimit(2) RLIMIT_NPROC is enforce based on real user ID.
>
> The commit 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
> made the accounting structure "indexed" by euid and hence potentially
> account tasks differently.
>
> The effective user ID may be different e.g. for setuid programs but
> those are exec'd into already existing task (i.e. below limit), so
> different accounting is moot.
>
> Some special setresuid(2) users may notice the difference, justifying
> this fix.
I looked at cred->ucount and it is only used for rlimit operations
that were previously stored in cred->user. Making the fact
cred->ucount can refer to a different user from cred->user a bug,
affecting all uses of cred->ulimit not just RLIMIT_NPROC.
Fix set_cred_ucounts to always use the real uid not the effective uid.
Further simplify set_cred_ucounts by noticing that set_cred_ucounts
somehow retained a draft version of the check to see if alloc_ucounts
was needed that checks the new->user and new->user_ns against the
current_real_cred(). Remove that draft version of the check.
All that matters for setting the cred->ucounts are the user_ns and uid
fields in the cred.
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20220207121800.5079-4-mkoutny@suse.com
Link: https://lkml.kernel.org/r/20220216155832.680775-3-ebiederm@xmission.com
Reported-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Fixes: 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Michal Koutný <mkoutny@suse.com> wrote:
> It was reported that v5.14 behaves differently when enforcing
> RLIMIT_NPROC limit, namely, it allows one more task than previously.
> This is consequence of the commit 21d1c5e386 ("Reimplement
> RLIMIT_NPROC on top of ucounts") that missed the sharpness of
> equality in the forking path.
This can be fixed either by fixing the test or by moving the increment
to be before the test. Fix it my moving copy_creds which contains
the increment before is_ucounts_overlimit.
In the case of CLONE_NEWUSER the ucounts in the task_cred changes.
The function is_ucounts_overlimit needs to use the final version of
the ucounts for the new process. Which means moving the
is_ucounts_overlimit test after copy_creds is necessary.
Both the test in fork and the test in set_user were semantically
changed when the code moved to ucounts. The change of the test in
fork was bad because it was before the increment. The test in
set_user was wrong and the change to ucounts fixed it. So this
fix only restores the old behavior in one lcation not two.
Link: https://lkml.kernel.org/r/20220204181144.24462-1-mkoutny@suse.com
Link: https://lkml.kernel.org/r/20220216155832.680775-2-ebiederm@xmission.com
Cc: stable@vger.kernel.org
Reported-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Fixes: 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
When the gadget driver hasn't been (yet) configured, and the cable is
connected to a HOST, the SFTDISCON gets cleared unconditionally, so the
HOST tries to enumerate it.
At the host side, this can result in a stuck USB port or worse. When
getting lucky, some dmesg can be observed at the host side:
new high-speed USB device number ...
device descriptor read/64, error -110
Fix it in drd, by checking the enabled flag before calling
dwc2_hsotg_core_connect(). It will be called later, once configured,
by the normal flow:
- udc_bind_to_driver
- usb_gadget_connect
- dwc2_hsotg_pullup
- dwc2_hsotg_core_connect
Fixes: 17f934024e ("usb: dwc2: override PHY input signals with usb role switch support")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/1644999135-13478-1-git-send-email-fabrice.gasnier@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the Bay Trail phy GPIO mappings where added cs and reset were swapped,
this did not cause any issues sofar, because sofar they were always driven
high/low at the same time.
Note the new mapping has been verified both in /sys/kernel/debug/gpio
output on Android factory images on multiple devices, as well as in
the schematics for some devices.
Fixes: 5741022cbd ("usb: dwc3: pci: Add GPIO lookup table on platforms without ACPI GPIO resources")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220213130524.18748-3-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Solar Designer <solar@openwall.com> wrote:
> I'm not aware of anyone actually running into this issue and reporting
> it. The systems that I personally know use suexec along with rlimits
> still run older/distro kernels, so would not yet be affected.
>
> So my mention was based on my understanding of how suexec works, and
> code review. Specifically, Apache httpd has the setting RLimitNPROC,
> which makes it set RLIMIT_NPROC:
>
> https://httpd.apache.org/docs/2.4/mod/core.html#rlimitnproc
>
> The above documentation for it includes:
>
> "This applies to processes forked from Apache httpd children servicing
> requests, not the Apache httpd children themselves. This includes CGI
> scripts and SSI exec commands, but not any processes forked from the
> Apache httpd parent, such as piped logs."
>
> In code, there are:
>
> ./modules/generators/mod_cgid.c: ( (cgid_req.limits.limit_nproc_set) && ((rc = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC,
> ./modules/generators/mod_cgi.c: ((rc = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC,
> ./modules/filters/mod_ext_filter.c: rv = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC, conf->limit_nproc);
>
> For example, in mod_cgi.c this is in run_cgi_child().
>
> I think this means an httpd child sets RLIMIT_NPROC shortly before it
> execs suexec, which is a SUID root program. suexec then switches to the
> target user and execs the CGI script.
>
> Before 2863643fb8, the setuid() in suexec would set the flag, and the
> target user's process count would be checked against RLIMIT_NPROC on
> execve(). After 2863643fb8, the setuid() in suexec wouldn't set the
> flag because setuid() is (naturally) called when the process is still
> running as root (thus, has those limits bypass capabilities), and
> accordingly execve() would not check the target user's process count
> against RLIMIT_NPROC.
In commit 2863643fb8 ("set_user: add capability check when
rlimit(RLIMIT_NPROC) exceeds") capable calls were added to set_user to
make it more consistent with fork. Unfortunately because of call site
differences those capable calls were checking the credentials of the
user before set*id() instead of after set*id().
This breaks enforcement of RLIMIT_NPROC for applications that set the
rlimit and then call set*id() while holding a full set of
capabilities. The capabilities are only changed in the new credential
in security_task_fix_setuid().
The code in apache suexec appears to follow this pattern.
Commit 909cc4ae86f3 ("[PATCH] Fix two bugs with process limits
(RLIMIT_NPROC)") where this check was added describes the targes of this
capability check as:
2/ When a root-owned process (e.g. cgiwrap) sets up process limits and then
calls setuid, the setuid should fail if the user would then be running
more than rlim_cur[RLIMIT_NPROC] processes, but it doesn't. This patch
adds an appropriate test. With this patch, and per-user process limit
imposed in cgiwrap really works.
So the original use case of this check also appears to match the broken
pattern.
Restore the enforcement of RLIMIT_NPROC by removing the bad capable
checks added in set_user. This unfortunately restores the
inconsistent state the code has been in for the last 11 years, but
dealing with the inconsistencies looks like a larger problem.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20210907213042.GA22626@openwall.com/
Link: https://lkml.kernel.org/r/20220212221412.GA29214@openwall.com
Link: https://lkml.kernel.org/r/20220216155832.680775-1-ebiederm@xmission.com
Fixes: 2863643fb8 ("set_user: add capability check when rlimit(RLIMIT_NPROC) exceeds")
History-Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Reviewed-by: Solar Designer <solar@openwall.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
