The following warning can occur when a pq is left on the dmawait list and
the pq is then freed:
WARNING: CPU: 47 PID: 3546 at lib/list_debug.c:29 __list_add+0x65/0xc0
list_add corruption. next->prev should be prev (ffff939228da1880), but was ffff939cabb52230. (next=ffff939cabb52230).
Modules linked in: mmfs26(OE) mmfslinux(OE) tracedev(OE) 8021q garp mrp ib_isert iscsi_target_mod target_core_mod crc_t10dif crct10dif_generic opa_vnic rpcrdma ib_iser libiscsi scsi_transport_iscsi ib_ipoib(OE) bridge stp llc iTCO_wdt iTCO_vendor_support intel_powerclamp coretemp intel_rapl iosf_mbi kvm_intel kvm irqbypass crct10dif_pclmul crct10dif_common crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd ast ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm pcspkr joydev drm_panel_orientation_quirks i2c_i801 mei_me lpc_ich mei wmi ipmi_si ipmi_devintf ipmi_msghandler nfit libnvdimm acpi_power_meter acpi_pad hfi1(OE) rdmavt(OE) rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_core binfmt_misc numatools(OE) xpmem(OE) ip_tables
nfsv3 nfs_acl nfs lockd grace sunrpc fscache igb ahci libahci i2c_algo_bit dca libata ptp pps_core crc32c_intel [last unloaded: i2c_algo_bit]
CPU: 47 PID: 3546 Comm: wrf.exe Kdump: loaded Tainted: G W OE ------------ 3.10.0-957.41.1.el7.x86_64 #1
Hardware name: HPE.COM HPE SGI 8600-XA730i Gen10/X11DPT-SB-SG007, BIOS SBED1229 01/22/2019
Call Trace:
[<ffffffff91f65ac0>] dump_stack+0x19/0x1b
[<ffffffff91898b78>] __warn+0xd8/0x100
[<ffffffff91898bff>] warn_slowpath_fmt+0x5f/0x80
[<ffffffff91a1dabe>] ? ___slab_alloc+0x24e/0x4f0
[<ffffffff91b97025>] __list_add+0x65/0xc0
[<ffffffffc03926a5>] defer_packet_queue+0x145/0x1a0 [hfi1]
[<ffffffffc0372987>] sdma_check_progress+0x67/0xa0 [hfi1]
[<ffffffffc03779d2>] sdma_send_txlist+0x432/0x550 [hfi1]
[<ffffffff91a20009>] ? kmem_cache_alloc+0x179/0x1f0
[<ffffffffc0392973>] ? user_sdma_send_pkts+0xc3/0x1990 [hfi1]
[<ffffffffc0393e3a>] user_sdma_send_pkts+0x158a/0x1990 [hfi1]
[<ffffffff918ab65e>] ? try_to_del_timer_sync+0x5e/0x90
[<ffffffff91a3fe1a>] ? __check_object_size+0x1ca/0x250
[<ffffffffc0395546>] hfi1_user_sdma_process_request+0xd66/0x1280 [hfi1]
[<ffffffffc034e0da>] hfi1_aio_write+0xca/0x120 [hfi1]
[<ffffffff91a4245b>] do_sync_readv_writev+0x7b/0xd0
[<ffffffff91a4409e>] do_readv_writev+0xce/0x260
[<ffffffff918df69f>] ? pick_next_task_fair+0x5f/0x1b0
[<ffffffff918db535>] ? sched_clock_cpu+0x85/0xc0
[<ffffffff91f6b16a>] ? __schedule+0x13a/0x860
[<ffffffff91a442c5>] vfs_writev+0x35/0x60
[<ffffffff91a4447f>] SyS_writev+0x7f/0x110
[<ffffffff91f78ddb>] system_call_fastpath+0x22/0x27
The issue happens when wait_event_interruptible_timeout() returns a value
<= 0.
In that case, the pq is left on the list. The code continues sending
packets and potentially can complete the current request with the pq still
on the dmawait list provided no descriptor shortage is seen.
If the pq is torn down in that state, the sdma interrupt handler could
find the now freed pq on the list with list corruption or memory
corruption resulting.
Fix by adding a flush routine to ensure that the pq is never on a list
after processing a request.
A follow-up patch series will address issues with seqlock surfaced in:
https://lore.kernel.org/r/20200320003129.GP20941@ziepe.ca
The seqlock use for sdma will then be converted to a spin lock since the
list_empty() doesn't need the protection afforded by the sequence lock
currently in use.
Fixes: a0d406934a ("staging/rdma/hfi1: Add page lock limit check for SDMA requests")
Link: https://lore.kernel.org/r/20200320200200.23203.37777.stgit@awfm-01.aw.intel.com
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Pull crypto fix from Herbert Xu:
"This fixes a correctness bug in the ARM64 version of ChaCha for
lib/crypto used by WireGuard"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: arm64/chacha - correctly walk through blocks
We always punt async buffered writes to an io-wq helper, as the core
kernel does not have IOCB_NOWAIT support for that. Most buffered async
writes complete very quickly, as it's just a copy operation. This means
that doing multiple locking roundtrips on the shared wqe lock for each
buffered write is wasteful. Additionally, buffered writes are hashed
work items, which means that any buffered write to a given file is
serialized.
Keep identicaly hashed work items contiguously in @wqe->work_list, and
track a tail for each hash bucket. On dequeue of a hashed item, splice
all of the same hash in one go using the tracked tail. Until the batch
is done, the caller doesn't have to synchronize with the wqe or worker
locks again.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When application uses TCP_QUEUE_SEQ socket option to
change tp->rcv_next, we must also update tp->copied_seq.
Otherwise, stuff relying on tcp_inq() being precise can
eventually be confused.
For example, tcp_zerocopy_receive() might crash because
it does not expect tcp_recv_skb() to return NULL.
We could add tests in various places to fix the issue,
or simply make sure tcp_inq() wont return a random value,
and leave fast path as it is.
Note that this fixes ioctl(fd, SIOCINQ, &val) at the same
time.
Fixes: ee9952831c ("tcp: Initial repair mode")
Fixes: 05255b823a ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
THUNK_TARGET defines [thunk_target] as having "rm" input constraints
when CONFIG_RETPOLINE is not set, which isn't constrained enough for
this specific case.
For inline assembly that modifies the stack pointer before using this
input, the underspecification of constraints is dangerous, and results
in an indirect call to a previously pushed flags register.
In this case `entry`'s stack slot is good enough to satisfy the "m"
constraint in "rm", but the inline assembly in
handle_external_interrupt_irqoff() modifies the stack pointer via
push+pushf before using this input, which in this case results in
calling what was the previous state of the flags register, rather than
`entry`.
Be more specific in the constraints by requiring `entry` be in a
register, and not a memory operand.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: syzbot+3f29ca2efb056a761e38@syzkaller.appspotmail.com
Debugged-by: Alexander Potapenko <glider@google.com>
Debugged-by: Paolo Bonzini <pbonzini@redhat.com>
Debugged-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Message-Id: <20200323191243.30002-1-ndesaulniers@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The GEO_TX_POWER_LIMIT command was sent although
there is no wgds table, so the fw got wrong SAR values
from the driver.
Fix this by avoiding sending the command if no wgds
tables are available.
Signed-off-by: Golan Ben Ami <golan.ben.ami@intel.com>
Fixes: 39c1a9728f ("iwlwifi: refactor the SAR tables from mvm to acpi")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Tested-By: Jonathan McDowell <noodles@earth.li>
Tested-by: Len Brown <len.brown@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/iwlwifi.20200318081237.46db40617cc6.Id5cf852ec8c5dbf20ba86bad7b165a0c828f8b2e@changeid
Sync removal of file is only used in case of a GFP_KERNEL kmalloc
failure at the cost of io_file_put::done and work flush, while a
glich like it can be handled at the call site without too much pain.
That said, what is proposed is to drop sync removing of file, and
the kink in neck as well.
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A case of task hung was reported by syzbot,
INFO: task syz-executor975:9880 blocked for more than 143 seconds.
Not tainted 5.6.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor975 D27576 9880 9878 0x80004000
Call Trace:
schedule+0xd0/0x2a0 kernel/sched/core.c:4154
schedule_timeout+0x6db/0xba0 kernel/time/timer.c:1871
do_wait_for_common kernel/sched/completion.c:83 [inline]
__wait_for_common kernel/sched/completion.c:104 [inline]
wait_for_common kernel/sched/completion.c:115 [inline]
wait_for_completion+0x26a/0x3c0 kernel/sched/completion.c:136
io_queue_file_removal+0x1af/0x1e0 fs/io_uring.c:5826
__io_sqe_files_update.isra.0+0x3a1/0xb00 fs/io_uring.c:5867
io_sqe_files_update fs/io_uring.c:5918 [inline]
__io_uring_register+0x377/0x2c00 fs/io_uring.c:7131
__do_sys_io_uring_register fs/io_uring.c:7202 [inline]
__se_sys_io_uring_register fs/io_uring.c:7184 [inline]
__x64_sys_io_uring_register+0x192/0x560 fs/io_uring.c:7184
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
and bisect pointed to 05f3fb3c53 ("io_uring: avoid ring quiesce for
fixed file set unregister and update").
It is down to the order that we wait for work done before flushing it
while nobody is likely going to wake us up.
We can drop that completion on stack as flushing work itself is a sync
operation we need and no more is left behind it.
To that end, io_file_put::done is re-used for indicating if it can be
freed in the workqueue worker context.
Reported-and-Inspired-by: syzbot <syzbot+538d1957ce178382a394@syzkaller.appspotmail.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Rename ->done to ->free_pfile
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, CLFLUSH is used to flush SEV guest memory before the guest is
terminated (or a memory hotplug region is removed). However, CLFLUSH is
not enough to ensure that SEV guest tagged data is flushed from the cache.
With 33af3a7ef9 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations"), the
original WBINVD was removed. This then exposed crashes at random times
because of a cache flush race with a page that had both a hypervisor and
a guest tag in the cache.
Restore the WBINVD when destroying an SEV guest and add a WBINVD to the
svm_unregister_enc_region() function to ensure hotplug memory is flushed
when removed. The DF_FLUSH can still be avoided at this point.
Fixes: 33af3a7ef9 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <c8bf9087ca3711c5770bdeaafa3e45b717dc5ef4.1584720426.git.thomas.lendacky@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make it so that CEPH_MSG_DATA_PAGES data item can own pages,
fixing a bunch of memory leaks for a page vector allocated in
alloc_msg_with_page_vector(). Currently, only watch-notify
messages trigger this allocation, and normally the page vector
is freed either in handle_watch_notify() or by the caller of
ceph_osdc_notify(). But if the message is freed before that
(e.g. if the session faults while reading in the message or
if the notify is stale), we leak the page vector.
This was supposed to be fixed by switching to a message-owned
pagelist, but that never happened.
Fixes: 1907920324 ("libceph: support for sending notifies")
Reported-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Roman Penyaev <rpenyaev@suse.de>
CEPH_OSDMAP_FULL/NEARFULL aren't set since mimic, so we need to consult
per-pool flags as well. Unfortunately the backwards compatibility here
is lacking:
- the change that deprecated OSDMAP_FULL/NEARFULL went into mimic, but
was guarded by require_osd_release >= RELEASE_LUMINOUS
- it was subsequently backported to luminous in v12.2.2, but that makes
no difference to clients that only check OSDMAP_FULL/NEARFULL because
require_osd_release is not client-facing -- it is for OSDs
Since all kernels are affected, the best we can do here is just start
checking both map flags and pool flags and send that to stable.
These checks are best effort, so take osdc->lock and look up pool flags
just once. Remove the FIXME, since filesystem quotas are checked above
and RADOS quotas are reflected in POOL_FLAG_FULL: when the pool reaches
its quota, both POOL_FLAG_FULL and POOL_FLAG_FULL_QUOTA are set.
Cc: stable@vger.kernel.org
Reported-by: Yanhu Cao <gmayyyha@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Sage Weil <sage@redhat.com>
Don't let non-letters inside a literal block without escaping it, as
the toolchain would mis-interpret it:
./include/linux/i2c.h:518: WARNING: Inline strong start-string without end-string.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Disable all rps-irq interrupts during driver initialization to prevent
an accidental interrupt on GIC.
Fixes: 84316f4ef1 ("ARM: boot: dts: Add Oxford Semiconductor OX810SE dtsi")
Fixes: 38d4a53733 ("ARM: dts: Add support for OX820 and Pogoplug V3")
Signed-off-by: Sungbo Eo <mans0n@gorani.run>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
All but one error handling paths in the 'k3_udma_glue_cfg_rx_flow()'
function 'goto err' and call 'k3_udma_glue_release_rx_flow()'.
This not correct because this function has a 'channel->flows_ready--;' at
the end, but 'flows_ready' has not been incremented here, when we branch to
the error handling path.
In order to keep a correct value in 'flows_ready', un-roll
'k3_udma_glue_release_rx_flow()', simplify it, add some labels and branch
at the correct places when an error is detected.
Doing so, we also NULLify 'flow->udma_rflow' in a path that was lacking it.
Fixes: d702419134 ("dmaengine: ti: k3-udma: Add glue layer for non DMAengine user")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200318191209.1267-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The refcount check for dedicated workqueue (dwq) is off by one and allows
more than 1 user to open the char device. Fix check so only a single user
can open the device.
Fixes: 42d279f913 ("dmaengine: idxd: add char driver to expose submission portal to userland")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/158403020187.10208.14117394394540710774.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
work->data and work->list are shared in union. io_wq_assign_next() sets
->data if a req having a linked_timeout, but then io-wq may want to use
work->list, e.g. to do re-enqueue of a request, so corrupting ->data.
->data is not necessary, just remove it and extract linked_timeout
through @link_list.
Fixes: 60cf46ae60 ("io-wq: hash dependent work")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The bus is virtual and devices have to inherit their DMA constraints
from the underlying interconnect. So add an empty dma-ranges property to
the bus node, implying the firmware bus' DMA constraints are identical to
its parent's.
Fixes: 7dbe8c62ce ("ARM: dts: Add minimal Raspberry Pi 4 support")
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
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Merge tag 'for-5.6-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Two fixes.
The first is a regression: when dropping some incompat bits the
conditions were reversed. The other is a fix for rename whiteout
potentially leaving stack memory linked to a list"
* tag 'for-5.6-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix removal of raid[56|1c34} incompat flags after removing block group
btrfs: fix log context list corruption after rename whiteout error
Merge misc fixes from Andrew Morton:
"10 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
x86/mm: split vmalloc_sync_all()
mm, slub: prevent kmalloc_node crashes and memory leaks
mm/mmu_notifier: silence PROVE_RCU_LIST warnings
epoll: fix possible lost wakeup on epoll_ctl() path
mm: do not allow MADV_PAGEOUT for CoW pages
mm, memcg: throttle allocators based on ancestral memory.high
mm, memcg: fix corruption on 64-bit divisor in memory.high throttling
page-flags: fix a crash at SetPageError(THP_SWAP)
mm/hotplug: fix hot remove failure in SPARSEMEM|!VMEMMAP case
memcg: fix NULL pointer dereference in __mem_cgroup_usage_unregister_event
After io_assign_current_work() of a linked work, it can be decided to
offloaded to another thread so doing io_wqe_enqueue(). However, until
next io_assign_current_work() it can be cancelled, that isn't handled.
Don't assign it, if it's not going to be executed.
Fixes: 60cf46ae60 ("io-wq: hash dependent work")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The driver forgets to disable and unprepare clk when remove.
Add a call to clk_disable_unprepare to fix it.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
The idea of this patch is from Davidlohr Bueso, he posts a patch
for bcache to optimize barrier usage for read-modify-write atomic
bitops. Indeed such optimization can also apply on other locations
where smp_mb() is used before or after an atomic operation.
This patch replaces smp_mb() with smp_mb__before_atomic() or
smp_mb__after_atomic() in btree.c and writeback.c, where it is used
to synchronize memory cache just earlier on other cores. Although
the locations are not on hot code path, it is always not bad to mkae
things a little better.
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We can avoid the unnecessary barrier on non LL/SC architectures,
such as x86. Instead, use the smp_mb__after_atomic().
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit. Fix it by replacing with scnprintf().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When attaching a cached device (a.k.a backing device) to a cache
device, bch_sectors_dirty_init() is called to count dirty sectors
and stripes (see what bcache_dev_sectors_dirty_add() does) on the
cache device.
The counting is done by a single thread recursive function
bch_btree_map_keys() to iterate all the bcache btree nodes.
If the btree has huge number of nodes, bch_sectors_dirty_init() will
take quite long time. In my testing, if the registering cache set has
a existed UUID which matches a already registered cached device, the
automatical attachment during the registration may take more than
55 minutes. This is too long for waiting the bcache to work in real
deployment.
Fortunately when bch_sectors_dirty_init() is called, no other thread
will access the btree yet, it is safe to do a read-only parallelized
dirty sectors counting by multiple threads.
This patch tries to create multiple threads, and each thread tries to
one-by-one count dirty sectors from the sub-tree indexed by a root
node key which the thread fetched. After the sub-tree is counted, the
counting thread will continue to fetch another root node key, until
the fetched key is NULL. How many threads in parallel depends on
the number of keys from the btree root node, and the number of online
CPU core. The thread number will be the less number but no more than
BCH_DIRTY_INIT_THRD_MAX. If there are only 2 keys in root node, it
can only be 2x times faster by this patch. But if there are 10 keys
in the root node, with this patch it can be 10x times faster.
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When registering a cache device, bch_btree_check() is called to check
all btree nodes, to make sure the btree is consistent and not
corrupted.
bch_btree_check() is recursively executed in a single thread, when there
are a lot of data cached and the btree is huge, it may take very long
time to check all the btree nodes. In my testing, I observed it took
around 50 minutes to finish bch_btree_check().
When checking the bcache btree nodes, the cache set is not running yet,
and indeed the whole tree is in read-only state, it is safe to create
multiple threads to check the btree in parallel.
This patch tries to create multiple threads, and each thread tries to
one-by-one check the sub-tree indexed by a key from the btree root node.
The parallel thread number depends on how many keys in the btree root
node. At most BCH_BTR_CHKTHREAD_MAX (64) threads can be created, but in
practice is should be min(cpu-number/2, root-node-keys-number).
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch changes macro btree_root() and btree() to bcache_btree_root()
and bcache_btree(), to avoid potential generic name clash in future.
NOTE: for product kernel maintainers, this patch can be skipped if
you feel the rename stuffs introduce inconvenince to patch backport.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In order to accelerate bcache registration speed, the macro btree()
and btree_root() will be referenced out of btree.c. This patch moves
them from btree.c into btree.h with other relative function declaration
in btree.h, for the following changes.
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Many systems build/test up-to-date kernels with older libcs, and
an older glibc (2.17) lacks the definition of SOL_DCCP in
/usr/include/bits/socket.h (it was added in the 4.6 timeframe).
Adding the definition to the test program avoids a compilation
failure that gets in the way of building tools/testing/selftests/net.
The test itself will work once the definition is added; either
skipping due to DCCP not being configured in the kernel under test
or passing, so there are no other more up-to-date glibc dependencies
here it seems beyond that missing definition.
Fixes: 11fb60d108 ("selftests: net: reuseport_addr_any: add DCCP")
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The hardware offloading of the NETIF_F_HW_CSUM and NETIF_F_RXCSUM
features requires the use of Transmit Status Blocks before transmit
frame data and Receive Status Blocks before receive frame data to
carry the checksum information.
Unfortunately, these status blocks are currently only enabled when
the NETIF_F_HW_CSUM feature is enabled. As a result NETIF_F_RXCSUM
will not actually be offloaded to the hardware unless both it and
NETIF_F_HW_CSUM are enabled. Fortunately, that is the default
configuration.
This commit addresses this issue by always enabling the use of
status blocks on both transmit and receive frames. Further, it
replaces the use of a dedicated flag within the driver private
data structure with direct use of the netdev features flags.
Fixes: 8101553978 ("net: bcmgenet: use CHECKSUM_COMPLETE for NETIF_F_RXCSUM")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the DP83867 PHY is strapped to enable Fast Link Drop (FLD) feature
STRAP_STS2.STRAP_ FLD (reg 0x006F bit 10), the Energy Lost Threshold for
FLD Energy Lost Mode FLD_THR_CFG.ENERGY_LOST_FLD_THR (reg 0x002e bits 2:0)
will be defaulted to 0x2. This may cause the phy link to be unstable. The
new DP83867 DM recommends to always restore ENERGY_LOST_FLD_THR to 0x1.
Hence, restore default value of FLD_THR_CFG.ENERGY_LOST_FLD_THR to 0x1 when
FLD is enabled by bootstrapping as recommended by DM.
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure we clean up devicetree related configuration
also when clock init fails.
Fixes: fecd4d7eef ("net: stmmac: dwmac-rk: Add integrated PHY support")
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
As the description before netdev_run_todo, we cannot call free_netdev
before rtnl_unlock, fix it by reorder the code.
This patch is a 1:1 copy of upstream slip.c commit f596c87005
("slip: not call free_netdev before rtnl_unlock in slip_open").
Reported-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Headers ionic_if.h and ionic_regs.h are licensed under three alternative
licenses and the used SPDX-License-Identifier expression makes
./scripts/spdxcheck.py complain:
drivers/net/ethernet/pensando/ionic/ionic_if.h: 1:52 Syntax error: OR
drivers/net/ethernet/pensando/ionic/ionic_regs.h: 1:52 Syntax error: OR
As OR is associative, it is irrelevant if the parentheses are put around
the first or the second OR-expression.
Simply add parentheses to make spdxcheck.py happy.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
The port->hsr is used in the hsr_handle_frame(), which is a
callback of rx_handler.
hsr master and slaves are initialized in hsr_add_port().
This function initializes several pointers, which includes port->hsr after
registering rx_handler.
So, in the rx_handler routine, un-initialized pointer would be used.
In order to fix this, pointers should be initialized before
registering rx_handler.
Test commands:
ip netns del left
ip netns del right
modprobe -rv veth
modprobe -rv hsr
killall ping
modprobe hsr
ip netns add left
ip netns add right
ip link add veth0 type veth peer name veth1
ip link add veth2 type veth peer name veth3
ip link add veth4 type veth peer name veth5
ip link set veth1 netns left
ip link set veth3 netns right
ip link set veth4 netns left
ip link set veth5 netns right
ip link set veth0 up
ip link set veth2 up
ip link set veth0 address fc:00:00:00:00:01
ip link set veth2 address fc:00:00:00:00:02
ip netns exec left ip link set veth1 up
ip netns exec left ip link set veth4 up
ip netns exec right ip link set veth3 up
ip netns exec right ip link set veth5 up
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip netns exec left ip link add hsr1 type hsr slave1 veth1 slave2 veth4
ip netns exec left ip a a 192.168.100.2/24 dev hsr1
ip netns exec left ip link set hsr1 up
ip netns exec left ip n a 192.168.100.1 dev hsr1 lladdr \
fc:00:00:00:00:01 nud permanent
ip netns exec left ip n r 192.168.100.1 dev hsr1 lladdr \
fc:00:00:00:00:01 nud permanent
for i in {1..100}
do
ip netns exec left ping 192.168.100.1 &
done
ip netns exec left hping3 192.168.100.1 -2 --flood &
ip netns exec right ip link add hsr2 type hsr slave1 veth3 slave2 veth5
ip netns exec right ip a a 192.168.100.3/24 dev hsr2
ip netns exec right ip link set hsr2 up
ip netns exec right ip n a 192.168.100.1 dev hsr2 lladdr \
fc:00:00:00:00:02 nud permanent
ip netns exec right ip n r 192.168.100.1 dev hsr2 lladdr \
fc:00:00:00:00:02 nud permanent
for i in {1..100}
do
ip netns exec right ping 192.168.100.1 &
done
ip netns exec right hping3 192.168.100.1 -2 --flood &
while :
do
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip link del hsr0
done
Splat looks like:
[ 120.954938][ C0] general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1]I
[ 120.957761][ C0] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
[ 120.959064][ C0] CPU: 0 PID: 1511 Comm: hping3 Not tainted 5.6.0-rc5+ #460
[ 120.960054][ C0] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 120.962261][ C0] RIP: 0010:hsr_addr_is_self+0x65/0x2a0 [hsr]
[ 120.963149][ C0] Code: 44 24 18 70 73 2f c0 48 c1 eb 03 48 8d 04 13 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 f2 4
[ 120.966277][ C0] RSP: 0018:ffff8880d9c09af0 EFLAGS: 00010206
[ 120.967293][ C0] RAX: 0000000000000006 RBX: 1ffff1101b38135f RCX: 0000000000000000
[ 120.968516][ C0] RDX: dffffc0000000000 RSI: ffff8880d17cb208 RDI: 0000000000000000
[ 120.969718][ C0] RBP: 0000000000000030 R08: ffffed101b3c0e3c R09: 0000000000000001
[ 120.972203][ C0] R10: 0000000000000001 R11: ffffed101b3c0e3b R12: 0000000000000000
[ 120.973379][ C0] R13: ffff8880aaf80100 R14: ffff8880aaf800f2 R15: ffff8880aaf80040
[ 120.974410][ C0] FS: 00007f58e693f740(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000
[ 120.979794][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 120.980773][ C0] CR2: 00007ffcb8b38f29 CR3: 00000000afe8e001 CR4: 00000000000606f0
[ 120.981945][ C0] Call Trace:
[ 120.982411][ C0] <IRQ>
[ 120.982848][ C0] ? hsr_add_node+0x8c0/0x8c0 [hsr]
[ 120.983522][ C0] ? rcu_read_lock_held+0x90/0xa0
[ 120.984159][ C0] ? rcu_read_lock_sched_held+0xc0/0xc0
[ 120.984944][ C0] hsr_handle_frame+0x1db/0x4e0 [hsr]
[ 120.985597][ C0] ? hsr_nl_nodedown+0x2b0/0x2b0 [hsr]
[ 120.986289][ C0] __netif_receive_skb_core+0x6bf/0x3170
[ 120.992513][ C0] ? check_chain_key+0x236/0x5d0
[ 120.993223][ C0] ? do_xdp_generic+0x1460/0x1460
[ 120.993875][ C0] ? register_lock_class+0x14d0/0x14d0
[ 120.994609][ C0] ? __netif_receive_skb_one_core+0x8d/0x160
[ 120.995377][ C0] __netif_receive_skb_one_core+0x8d/0x160
[ 120.996204][ C0] ? __netif_receive_skb_core+0x3170/0x3170
[ ... ]
Reported-by: syzbot+fcf5dd39282ceb27108d@syzkaller.appspotmail.com
Fixes: c5a7591172 ("net/hsr: Use list_head (and rcu) instead of array for slave devices.")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Luo bin says:
====================
hinic: BugFixes
Fix a number of bugs which have been present since the first commit.
The bugs fixed in these patchs are hardly exposed unless given
very specific conditions.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
the minimum value of skb len that hw supports is 32 rather than 17
Signed-off-by: Luo bin <luobin9@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
the second input parameter of wait_for_completion_timeout should
be jiffies instead of millisecond
Signed-off-by: Luo bin <luobin9@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
add read barrier in driver code to keep from reading other fileds
in dma memory which is writable for hw until we have verified the
memory is valid for driver
Signed-off-by: Luo bin <luobin9@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
should disable eq irq before freeing it, must clear event queue
depth in hw before freeing relevant memory to avoid illegal
memory access and update consumer idx to avoid invalid interrupt
Signed-off-by: Luo bin <luobin9@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
it's unreliable for fw to check whether IO is stopped, so driver
wait for enough time to ensure IO process is done in hw before
freeing resources
Signed-off-by: Luo bin <luobin9@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 3f8fd02b1b ("mm/vmalloc: Sync unmappings in
__purge_vmap_area_lazy()") introduced a call to vmalloc_sync_all() in
the vunmap() code-path. While this change was necessary to maintain
correctness on x86-32-pae kernels, it also adds additional cycles for
architectures that don't need it.
Specifically on x86-64 with CONFIG_VMAP_STACK=y some people reported
severe performance regressions in micro-benchmarks because it now also
calls the x86-64 implementation of vmalloc_sync_all() on vunmap(). But
the vmalloc_sync_all() implementation on x86-64 is only needed for newly
created mappings.
To avoid the unnecessary work on x86-64 and to gain the performance
back, split up vmalloc_sync_all() into two functions:
* vmalloc_sync_mappings(), and
* vmalloc_sync_unmappings()
Most call-sites to vmalloc_sync_all() only care about new mappings being
synchronized. The only exception is the new call-site added in the
above mentioned commit.
Shile Zhang directed us to a report of an 80% regression in reaim
throughput.
Fixes: 3f8fd02b1b ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [GHES]
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20191009124418.8286-1-joro@8bytes.org
Link: https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/4D3JPPHBNOSPFK2KEPC6KGKS6J25AIDB/
Link: http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sachin reports [1] a crash in SLUB __slab_alloc():
BUG: Kernel NULL pointer dereference on read at 0x000073b0
Faulting instruction address: 0xc0000000003d55f4
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 19 PID: 1 Comm: systemd Not tainted 5.6.0-rc2-next-20200218-autotest #1
NIP: c0000000003d55f4 LR: c0000000003d5b94 CTR: 0000000000000000
REGS: c0000008b37836d0 TRAP: 0300 Not tainted (5.6.0-rc2-next-20200218-autotest)
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 24004844 XER: 00000000
CFAR: c00000000000dec4 DAR: 00000000000073b0 DSISR: 40000000 IRQMASK: 1
GPR00: c0000000003d5b94 c0000008b3783960 c00000000155d400 c0000008b301f500
GPR04: 0000000000000dc0 0000000000000002 c0000000003443d8 c0000008bb398620
GPR08: 00000008ba2f0000 0000000000000001 0000000000000000 0000000000000000
GPR12: 0000000024004844 c00000001ec52a00 0000000000000000 0000000000000000
GPR16: c0000008a1b20048 c000000001595898 c000000001750c18 0000000000000002
GPR20: c000000001750c28 c000000001624470 0000000fffffffe0 5deadbeef0000122
GPR24: 0000000000000001 0000000000000dc0 0000000000000002 c0000000003443d8
GPR28: c0000008b301f500 c0000008bb398620 0000000000000000 c00c000002287180
NIP ___slab_alloc+0x1f4/0x760
LR __slab_alloc+0x34/0x60
Call Trace:
___slab_alloc+0x334/0x760 (unreliable)
__slab_alloc+0x34/0x60
__kmalloc_node+0x110/0x490
kvmalloc_node+0x58/0x110
mem_cgroup_css_online+0x108/0x270
online_css+0x48/0xd0
cgroup_apply_control_enable+0x2ec/0x4d0
cgroup_mkdir+0x228/0x5f0
kernfs_iop_mkdir+0x90/0xf0
vfs_mkdir+0x110/0x230
do_mkdirat+0xb0/0x1a0
system_call+0x5c/0x68
This is a PowerPC platform with following NUMA topology:
available: 2 nodes (0-1)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 1 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
node 1 size: 35247 MB
node 1 free: 30907 MB
node distances:
node 0 1
0: 10 40
1: 40 10
possible numa nodes: 0-31
This only happens with a mmotm patch "mm/memcontrol.c: allocate
shrinker_map on appropriate NUMA node" [2] which effectively calls
kmalloc_node for each possible node. SLUB however only allocates
kmem_cache_node on online N_NORMAL_MEMORY nodes, and relies on
node_to_mem_node to return such valid node for other nodes since commit
a561ce00b0 ("slub: fall back to node_to_mem_node() node if allocating
on memoryless node"). This is however not true in this configuration
where the _node_numa_mem_ array is not initialized for nodes 0 and 2-31,
thus it contains zeroes and get_partial() ends up accessing
non-allocated kmem_cache_node.
A related issue was reported by Bharata (originally by Ramachandran) [3]
where a similar PowerPC configuration, but with mainline kernel without
patch [2] ends up allocating large amounts of pages by kmalloc-1k
kmalloc-512. This seems to have the same underlying issue with
node_to_mem_node() not behaving as expected, and might probably also
lead to an infinite loop with CONFIG_SLUB_CPU_PARTIAL [4].
This patch should fix both issues by not relying on node_to_mem_node()
anymore and instead simply falling back to NUMA_NO_NODE, when
kmalloc_node(node) is attempted for a node that's not online, or has no
usable memory. The "usable memory" condition is also changed from
node_present_pages() to N_NORMAL_MEMORY node state, as that is exactly
the condition that SLUB uses to allocate kmem_cache_node structures.
The check in get_partial() is removed completely, as the checks in
___slab_alloc() are now sufficient to prevent get_partial() being
reached with an invalid node.
[1] https://lore.kernel.org/linux-next/3381CD91-AB3D-4773-BA04-E7A072A63968@linux.vnet.ibm.com/
[2] https://lore.kernel.org/linux-mm/fff0e636-4c36-ed10-281c-8cdb0687c839@virtuozzo.com/
[3] https://lore.kernel.org/linux-mm/20200317092624.GB22538@in.ibm.com/
[4] https://lore.kernel.org/linux-mm/088b5996-faae-8a56-ef9c-5b567125ae54@suse.cz/
Fixes: a561ce00b0 ("slub: fall back to node_to_mem_node() node if allocating on memoryless node")
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Reported-by: PUVICHAKRAVARTHY RAMACHANDRAN <puvichakravarthy@in.ibm.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Bharata B Rao <bharata@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christopher Lameter <cl@linux.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200320115533.9604-1-vbabka@suse.cz
Debugged-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is safe to traverse mm->notifier_subscriptions->list either under
SRCU read lock or mm->notifier_subscriptions->lock using
hlist_for_each_entry_rcu(). Silence the PROVE_RCU_LIST false positives,
for example,
WARNING: suspicious RCU usage
-----------------------------
mm/mmu_notifier.c:484 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
3 locks held by libvirtd/802:
#0: ffff9321e3f58148 (&mm->mmap_sem#2){++++}, at: do_mprotect_pkey+0xe1/0x3e0
#1: ffffffff91ae6160 (mmu_notifier_invalidate_range_start){+.+.}, at: change_p4d_range+0x5fa/0x800
#2: ffffffff91ae6e08 (srcu){....}, at: __mmu_notifier_invalidate_range_start+0x178/0x460
stack backtrace:
CPU: 7 PID: 802 Comm: libvirtd Tainted: G I 5.6.0-rc6-next-20200317+ #2
Hardware name: HP ProLiant BL460c Gen8, BIOS I31 11/02/2014
Call Trace:
dump_stack+0xa4/0xfe
lockdep_rcu_suspicious+0xeb/0xf5
__mmu_notifier_invalidate_range_start+0x3ff/0x460
change_p4d_range+0x746/0x800
change_protection+0x1df/0x300
mprotect_fixup+0x245/0x3e0
do_mprotect_pkey+0x23b/0x3e0
__x64_sys_mprotect+0x51/0x70
do_syscall_64+0x91/0xae8
entry_SYSCALL_64_after_hwframe+0x49/0xb3
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Link: http://lkml.kernel.org/r/20200317175640.2047-1-cai@lca.pw
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes possible lost wakeup introduced by commit a218cc4914.
Originally modifications to ep->wq were serialized by ep->wq.lock, but
in commit a218cc4914 ("epoll: use rwlock in order to reduce
ep_poll_callback() contention") a new rw lock was introduced in order to
relax fd event path, i.e. callers of ep_poll_callback() function.
After the change ep_modify and ep_insert (both are called on epoll_ctl()
path) were switched to ep->lock, but ep_poll (epoll_wait) was using
ep->wq.lock on wqueue list modification.
The bug doesn't lead to any wqueue list corruptions, because wake up
path and list modifications were serialized by ep->wq.lock internally,
but actual waitqueue_active() check prior wake_up() call can be
reordered with modifications of ep ready list, thus wake up can be lost.
And yes, can be healed by explicit smp_mb():
list_add_tail(&epi->rdlink, &ep->rdllist);
smp_mb();
if (waitqueue_active(&ep->wq))
wake_up(&ep->wp);
But let's make it simple, thus current patch replaces ep->wq.lock with
the ep->lock for wqueue modifications, thus wake up path always observes
activeness of the wqueue correcty.
Fixes: a218cc4914 ("epoll: use rwlock in order to reduce ep_poll_callback() contention")
Reported-by: Max Neunhoeffer <max@arangodb.com>
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Max Neunhoeffer <max@arangodb.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Christopher Kohlhoff <chris.kohlhoff@clearpool.io>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Jes Sorensen <jes.sorensen@gmail.com>
Cc: <stable@vger.kernel.org> [5.1+]
Link: http://lkml.kernel.org/r/20200214170211.561524-1-rpenyaev@suse.de
References: https://bugzilla.kernel.org/show_bug.cgi?id=205933
Bisected-by: Max Neunhoeffer <max@arangodb.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
