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A number of architectures have non-pagetable aligned huge/large pages.
For such architectures a leaf can actually be part of a larger entry.
Provide generic helpers to determine the size of a page-table leaf.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lkml.kernel.org/r/20201126121121.102580109@infradead.org
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In order to write another lockless page-table walker, we need
gup_get_pte() exposed. While doing that, rename it to
ptep_get_lockless() to match the existing ptep_get() naming.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201126121121.036370527@infradead.org
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Further perf/core patches will depend on:
d3f7b1bb2040 ("mm/gup: fix gup_fast with dynamic page table folding")
which is already in Linus' tree.
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"A couple of scheduler fixes:
- Make the conditional update of the overutilized state work
correctly by caching the relevant flags state before overwriting
them and checking them afterwards.
- Fix a data race in the wakeup path which caused loadavg on ARM64
platforms to become a random number generator.
- Fix the ordering of the iowaiter accounting operations so it can't
be decremented before it is incremented.
- Fix a bug in the deadline scheduler vs. priority inheritance when a
non-deadline task A has inherited the parameters of a deadline task
B and then blocks on a non-deadline task C.
The second inheritance step used the static deadline parameters of
task A, which are usually 0, instead of further propagating task
B's parameters. The zero initialized parameters trigger a bug in
the deadline scheduler"
* tag 'sched-urgent-2020-11-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/deadline: Fix priority inheritance with multiple scheduling classes
sched: Fix rq->nr_iowait ordering
sched: Fix data-race in wakeup
sched/fair: Fix overutilized update in enqueue_task_fair()
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Merge misc fixes from Andrew Morton:
"8 patches.
Subsystems affected by this patch series: mm (madvise, pagemap,
readahead, memcg, userfaultfd), kbuild, and vfs"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: fix madvise WILLNEED performance problem
libfs: fix error cast of negative value in simple_attr_write()
mm/userfaultfd: do not access vma->vm_mm after calling handle_userfault()
mm: memcg/slab: fix root memcg vmstats
mm: fix readahead_page_batch for retry entries
mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports
compiler-clang: remove version check for BPF Tracing
mm/madvise: fix memory leak from process_madvise
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git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"A final set of miscellaneous bug fixes for ext4"
* tag 'ext4_for_linus_fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix bogus warning in ext4_update_dx_flag()
jbd2: fix kernel-doc markups
ext4: drop fast_commit from /proc/mounts
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Both btrfs and fuse have reported faults caused by seeing a retry entry
instead of the page they were looking for. This was caused by a missing
check in the iterator.
As can be seen in the below panic log, the accessing 0x402 causes a
panic. In the xarray.h, 0x402 means RETRY_ENTRY.
BUG: kernel NULL pointer dereference, address: 0000000000000402
CPU: 14 PID: 306003 Comm: as Not tainted 5.9.0-1-amd64 #1 Debian 5.9.1-1
Hardware name: Lenovo ThinkSystem SR665/7D2VCTO1WW, BIOS D8E106Q-1.01 05/30/2020
RIP: 0010:fuse_readahead+0x152/0x470 [fuse]
Code: 41 8b 57 18 4c 8d 54 10 ff 4c 89 d6 48 8d 7c 24 10 e8 d2 e3 28 f9 48 85 c0 0f 84 fe 00 00 00 44 89 f2 49 89 04 d4 44 8d 72 01 <48> 8b 10 41 8b 4f 1c 48 c1 ea 10 83 e2 01 80 fa 01 19 d2 81 e2 01
RSP: 0018:ffffad99ceaebc50 EFLAGS: 00010246
RAX: 0000000000000402 RBX: 0000000000000001 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffff94c5af90bd98 RDI: ffffad99ceaebc60
RBP: ffff94ddc1749a00 R08: 0000000000000402 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000100 R12: ffff94de6c429ce0
R13: ffff94de6c4d3700 R14: 0000000000000001 R15: ffffad99ceaebd68
FS: 00007f228c5c7040(0000) GS:ffff94de8ed80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000402 CR3: 0000001dbd9b4000 CR4: 0000000000350ee0
Call Trace:
read_pages+0x83/0x270
page_cache_readahead_unbounded+0x197/0x230
generic_file_buffered_read+0x57a/0xa20
new_sync_read+0x112/0x1a0
vfs_read+0xf8/0x180
ksys_read+0x5f/0xe0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 042124cc64c3 ("mm: add new readahead_control API")
Reported-by: David Sterba <dsterba@suse.com>
Reported-by: Wonhyuk Yang <vvghjk1234@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20201103142852.8543-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20201103124349.16722-1-vvghjk1234@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The core-mm has a default __weak implementation of phys_to_target_node()
to mirror the weak definition of memory_add_physaddr_to_nid(). That
symbol is exported for modules. However, while the export in
mm/memory_hotplug.c exported the symbol in the configuration cases of:
CONFIG_NUMA_KEEP_MEMINFO=y
CONFIG_MEMORY_HOTPLUG=y
...and:
CONFIG_NUMA_KEEP_MEMINFO=n
CONFIG_MEMORY_HOTPLUG=y
...it failed to export the symbol in the case of:
CONFIG_NUMA_KEEP_MEMINFO=y
CONFIG_MEMORY_HOTPLUG=n
Not only is that broken, but Christoph points out that the kernel should
not be exporting any __weak symbol, which means that
memory_add_physaddr_to_nid() example that phys_to_target_node() copied
is broken too.
Rework the definition of phys_to_target_node() and
memory_add_physaddr_to_nid() to not require weak symbols. Move to the
common arch override design-pattern of an asm header defining a symbol
to replace the default implementation.
The only common header that all memory_add_physaddr_to_nid() producing
architectures implement is asm/sparsemem.h. In fact, powerpc already
defines its memory_add_physaddr_to_nid() helper in sparsemem.h.
Double-down on that observation and define phys_to_target_node() where
necessary in asm/sparsemem.h. An alternate consideration that was
discarded was to put this override in asm/numa.h, but that entangles
with the definition of MAX_NUMNODES relative to the inclusion of
linux/nodemask.h, and requires powerpc to grow a new header.
The dependency on NUMA_KEEP_MEMINFO for DEV_DAX_HMEM_DEVICES is invalid
now that the symbol is properly exported / stubbed in all combinations
of CONFIG_NUMA_KEEP_MEMINFO and CONFIG_MEMORY_HOTPLUG.
[dan.j.williams@intel.com: v4]
Link: https://lkml.kernel.org/r/160461461867.1505359.5301571728749534585.stgit@dwillia2-desk3.amr.corp.intel.com
[dan.j.williams@intel.com: powerpc: fix create_section_mapping compile warning]
Link: https://lkml.kernel.org/r/160558386174.2948926.2740149041249041764.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: a035b6bf863e ("mm/memory_hotplug: introduce default phys_to_target_node() implementation")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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bpftrace parses the kernel headers and uses Clang under the hood.
Remove the version check when __BPF_TRACING__ is defined (as bpftrace
does) so that this tool can continue to parse kernel headers, even with
older clang sources.
Fixes: commit 1f7a44f63e6c ("compiler-clang: add build check for clang 10.0.1")
Reported-by: Chen Yu <yu.chen.surf@gmail.com>
Reported-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jarkko Sakkinen <jarkko@kernel.org>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lkml.kernel.org/r/20201104191052.390657-1-ndesaulniers@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Fixes for two fairly obscure but annoying when triggered races in
iSCSI"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: target: iscsi: Fix cmd abort fabric stop race
scsi: libiscsi: Fix NOP race condition
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull iommu fixes from Will Deacon:
"Two straightforward vt-d fixes:
- Fix boot when intel iommu initialisation fails under TXT (tboot)
- Fix intel iommu compilation error when DMAR is enabled without ATS
and temporarily update IOMMU MAINTAINERs entry"
* tag 'iommu-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
MAINTAINERS: Temporarily add myself to the IOMMU entry
iommu/vt-d: Fix compile error with CONFIG_PCI_ATS not set
iommu/vt-d: Avoid panic if iommu init fails in tboot system
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git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A collection of small fixes: the only core change is a minor error
code handling in the control API, and all the rest are device-specific
fixes, mostly quirks, fixups and ASoC Intel fixes.
It looks boring, and good so"
* tag 'sound-5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: mixart: Fix mutex deadlock
ALSA: hda/ca0132: Fix compile warning without PCI
ASOC: Intel: kbl_rt5663_rt5514_max98927: Do not try to disable disabled clock
ALSA: usb-audio: Add delay quirk for all Logitech USB devices
ASoC: Intel: catpt: Correct clock selection for dai trigger
ASoC: Intel: catpt: Skip position update for unprepared streams
ASoC: qcom: lpass-platform: Fix memory leak
ASoC: Intel: KMB: Fix S24_LE configuration
ALSA: hda: Add Alderlake-S PCI ID and HDMI codec vid
ALSA: usb-audio: Use ALC1220-VB-DT mapping for ASUS ROG Strix TRX40 mobo
ALSA: firewire: Clean up a locking issue in copy_resp_to_buf()
ASoC: rt1015: increase the time to detect BCLK
ALSA: ctl: fix error path at adding user-defined element set
ALSA: hda/realtek - HP Headset Mic can't detect after boot
ALSA: hda/realtek - Add supported mute Led for HP
ALSA: hda/realtek: Add some Clove SSID in the ALC293(ALC1220)
ALSA: hda/realtek - Add supported for Lenovo ThinkPad Headset Button
ASoC: rt1015: add delay to fix pop noise from speaker
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Kernel-doc markup should use this format:
identifier - description
They should not have any type before that, as otherwise
the parser won't do the right thing.
Also, some identifiers have different names between their
prototypes and the kernel-doc markup.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/72f5c6628f5f278d67625f60893ffbc2ca28d46e.1605521731.git.mchehab+huawei@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Networking fixes for 5.10-rc5, including fixes from the WiFi
(mac80211), can and bpf (including the strncpy_from_user fix).
Current release - regressions:
- mac80211: fix memory leak of filtered powersave frames
- mac80211: free sta in sta_info_insert_finish() on errors to avoid
sleeping in atomic context
- netlabel: fix an uninitialized variable warning added in -rc4
Previous release - regressions:
- vsock: forward all packets to the host when no H2G is registered,
un-breaking AWS Nitro Enclaves
- net: Exempt multicast addresses from five-second neighbor lifetime
requirement, decreasing the chances neighbor tables fill up
- net/tls: fix corrupted data in recvmsg
- qed: fix ILT configuration of SRC block
- can: m_can: process interrupt only when not runtime suspended
Previous release - always broken:
- page_frag: Recover from memory pressure by not recycling pages
allocating from the reserves
- strncpy_from_user: Mask out bytes after NUL terminator
- ip_tunnels: Set tunnel option flag only when tunnel metadata is
present, always setting it confuses Open vSwitch
- bpf, sockmap:
- Fix partial copy_page_to_iter so progress can still be made
- Fix socket memory accounting and obeying SO_RCVBUF
- net: Have netpoll bring-up DSA management interface
- net: bridge: add missing counters to ndo_get_stats64 callback
- tcp: brr: only postpone PROBE_RTT if RTT is < current min_rtt
- enetc: Workaround MDIO register access HW bug
- net/ncsi: move netlink family registration to a subsystem init,
instead of tying it to driver probe
- net: ftgmac100: unregister NC-SI when removing driver to avoid
crash
- lan743x:
- prevent interrupt storm on open
- fix freeing skbs in the wrong context
- net/mlx5e: Fix socket refcount leak on kTLS RX resync
- net: dsa: mv88e6xxx: Avoid VLAN database corruption on 6097
- fix 21 unset return codes and other mistakes on error paths, mostly
detected by the Hulk Robot"
* tag 'net-5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (115 commits)
fail_function: Remove a redundant mutex unlock
selftest/bpf: Test bpf_probe_read_user_str() strips trailing bytes after NUL
lib/strncpy_from_user.c: Mask out bytes after NUL terminator.
net/smc: fix direct access to ib_gid_addr->ndev in smc_ib_determine_gid()
net/smc: fix matching of existing link groups
ipv6: Remove dependency of ipv6_frag_thdr_truncated on ipv6 module
libbpf: Fix VERSIONED_SYM_COUNT number parsing
net/mlx4_core: Fix init_hca fields offset
atm: nicstar: Unmap DMA on send error
page_frag: Recover from memory pressure
net: dsa: mv88e6xxx: Wait for EEPROM done after HW reset
mlxsw: core: Use variable timeout for EMAD retries
mlxsw: Fix firmware flashing
net: Have netpoll bring-up DSA management interface
atl1e: fix error return code in atl1e_probe()
atl1c: fix error return code in atl1c_probe()
ah6: fix error return code in ah6_input()
net: usb: qmi_wwan: Set DTR quirk for MR400
can: m_can: process interrupt only when not runtime suspended
can: flexcan: flexcan_chip_start(): fix erroneous flexcan_transceiver_enable() during bus-off recovery
...
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"This is a relatively large set of fixes, the bulk of it being a series
from Lukas Wunner which fixes confusion with the lifetime of driver
data allocated along with the SPI controller structure that's been
created as part of the conversion to devm APIs.
The simplest fix, explained in detail in Lukas' commit message, is to
move to a devm_ function for allocation of the controller and hence
driver data in order to push the free of that after anything tries to
reference the driver data in the remove path. This results in a
relatively large diff due to the addition of a new function but isn't
particularly complex.
There's also a fix from Sven van Asbroeck which fixes yet more fallout
from the conflicts between the various different places one can
configure the polarity of GPIOs in modern systems.
Otherwise everything is fairly small and driver specific"
* tag 'spi-fix-v5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: npcm-fiu: Don't leak SPI master in probe error path
spi: dw: Set transfer handler before unmasking the IRQs
spi: cadence-quadspi: Fix error return code in cqspi_probe
spi: bcm2835aux: Restore err assignment in bcm2835aux_spi_probe
spi: lpspi: Fix use-after-free on unbind
spi: bcm-qspi: Fix use-after-free on unbind
spi: bcm2835aux: Fix use-after-free on unbind
spi: bcm2835: Fix use-after-free on unbind
spi: Introduce device-managed SPI controller allocation
spi: fsi: Fix transfer returning without finalizing message
spi: fix client driver breakages when using GPIO descriptors
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https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v5.11
A collection of driver specific fixes, mostly for x86 systems (or CODECs
used mostly on x86) and all for relatively minor issues, the biggest one
being fixing S24_LE format on Keem Bay systems.
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IPV6=m
NF_DEFRAG_IPV6=y
ld: net/ipv6/netfilter/nf_conntrack_reasm.o: in function
`nf_ct_frag6_gather':
net/ipv6/netfilter/nf_conntrack_reasm.c:462: undefined reference to
`ipv6_frag_thdr_truncated'
Netfilter is depending on ipv6 symbol ipv6_frag_thdr_truncated. This
dependency is forcing IPV6=y.
Remove this dependency by moving ipv6_frag_thdr_truncated out of ipv6. This
is the same solution as used with a similar issues: Referring to
commit 70b095c843266 ("ipv6: remove dependency of nf_defrag_ipv6 on ipv6
module")
Fixes: 9d9e937b1c8b ("ipv6/netfilter: Discard first fragment not including all headers")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Georg Kohmann <geokohma@cisco.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/r/20201119095833.8409-1-geokohma@cisco.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Pull nfsd fix from Bruce Fields:
"Just one quick fix for a tracing oops"
* tag 'nfsd-5.10-2' of git://linux-nfs.org/~bfields/linux:
SUNRPC: Fix oops in the rpc_xdr_buf event class
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git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kunit fixes from Shuah Khan:
"Several fixes to Kunit documentation and tools, and to not pollute
the source directory.
Also remove the incorrect kunit .gitattributes file"
* tag 'linux-kselftest-kunit-fixes-5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: fix display of failed expectations for strings
kunit: tool: fix extra trailing \n in raw + parsed test output
kunit: tool: print out stderr from make (like build warnings)
KUnit: Docs: usage: wording fixes
KUnit: Docs: style: fix some Kconfig example issues
KUnit: Docs: fix a wording typo
kunit: Do not pollute source directory with generated files (test.log)
kunit: Do not pollute source directory with generated files (.kunitconfig)
kunit: tool: fix pre-existing python type annotation errors
kunit: Fix kunit.py parse subcommand (use null build_dir)
kunit: tool: unmark test_data as binary blobs
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"intel_iommu=off" command line is used to disable iommu but iommu is force
enabled in a tboot system for security reason.
However for better performance on high speed network device, a new option
"intel_iommu=tboot_noforce" is introduced to disable the force on.
By default kernel should panic if iommu init fail in tboot for security
reason, but it's unnecessory if we use "intel_iommu=tboot_noforce,off".
Fix the code setting force_on and move intel_iommu_tboot_noforce
from tboot code to intel iommu code.
Fixes: 7304e8f28bb2 ("iommu/vt-d: Correctly disable Intel IOMMU force on")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com>
Tested-by: Lukasz Hawrylko <lukasz.hawrylko@linux.intel.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201110071908.3133-1-zhenzhong.duan@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
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In async_resync mode, we log the TCP seq of records until the async request
is completed. Later, in case one of the logged seqs matches the resync
request, we return it, together with its record serial number. Before this
fix, we mistakenly returned the serial number of the current record
instead.
Fixes: ed9b7646b06a ("net/tls: Add asynchronous resync")
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Boris Pismenny <borisp@nvidia.com>
Link: https://lore.kernel.org/r/20201115131448.2702-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Glenn reported that "an application [he developed produces] a BUG in
deadline.c when a SCHED_DEADLINE task contends with CFS tasks on nested
PTHREAD_PRIO_INHERIT mutexes. I believe the bug is triggered when a CFS
task that was boosted by a SCHED_DEADLINE task boosts another CFS task
(nested priority inheritance).
------------[ cut here ]------------
kernel BUG at kernel/sched/deadline.c:1462!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 12 PID: 19171 Comm: dl_boost_bug Tainted: ...
Hardware name: ...
RIP: 0010:enqueue_task_dl+0x335/0x910
Code: ...
RSP: 0018:ffffc9000c2bbc68 EFLAGS: 00010002
RAX: 0000000000000009 RBX: ffff888c0af94c00 RCX: ffffffff81e12500
RDX: 000000000000002e RSI: ffff888c0af94c00 RDI: ffff888c10b22600
RBP: ffffc9000c2bbd08 R08: 0000000000000009 R09: 0000000000000078
R10: ffffffff81e12440 R11: ffffffff81e1236c R12: ffff888bc8932600
R13: ffff888c0af94eb8 R14: ffff888c10b22600 R15: ffff888bc8932600
FS: 00007fa58ac55700(0000) GS:ffff888c10b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa58b523230 CR3: 0000000bf44ab003 CR4: 00000000007606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
? intel_pstate_update_util_hwp+0x13/0x170
rt_mutex_setprio+0x1cc/0x4b0
task_blocks_on_rt_mutex+0x225/0x260
rt_spin_lock_slowlock_locked+0xab/0x2d0
rt_spin_lock_slowlock+0x50/0x80
hrtimer_grab_expiry_lock+0x20/0x30
hrtimer_cancel+0x13/0x30
do_nanosleep+0xa0/0x150
hrtimer_nanosleep+0xe1/0x230
? __hrtimer_init_sleeper+0x60/0x60
__x64_sys_nanosleep+0x8d/0xa0
do_syscall_64+0x4a/0x100
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fa58b52330d
...
---[ end trace 0000000000000002 ]—
He also provided a simple reproducer creating the situation below:
So the execution order of locking steps are the following
(N1 and N2 are non-deadline tasks. D1 is a deadline task. M1 and M2
are mutexes that are enabled * with priority inheritance.)
Time moves forward as this timeline goes down:
N1 N2 D1
| | |
| | |
Lock(M1) | |
| | |
| Lock(M2) |
| | |
| | Lock(M2)
| | |
| Lock(M1) |
| (!!bug triggered!) |
Daniel reported a similar situation as well, by just letting ksoftirqd
run with DEADLINE (and eventually block on a mutex).
Problem is that boosted entities (Priority Inheritance) use static
DEADLINE parameters of the top priority waiter. However, there might be
cases where top waiter could be a non-DEADLINE entity that is currently
boosted by a DEADLINE entity from a different lock chain (i.e., nested
priority chains involving entities of non-DEADLINE classes). In this
case, top waiter static DEADLINE parameters could be null (initialized
to 0 at fork()) and replenish_dl_entity() would hit a BUG().
Fix this by keeping track of the original donor and using its parameters
when a task is boosted.
Reported-by: Glenn Elliott <glenn@aurora.tech>
Reported-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Link: https://lkml.kernel.org/r/20201117061432.517340-1-juri.lelli@redhat.com
|
|
Mel reported that on some ARM64 platforms loadavg goes bananas and
Will tracked it down to the following race:
CPU0 CPU1
schedule()
prev->sched_contributes_to_load = X;
deactivate_task(prev);
try_to_wake_up()
if (p->on_rq &&) // false
if (smp_load_acquire(&p->on_cpu) && // true
ttwu_queue_wakelist())
p->sched_remote_wakeup = Y;
smp_store_release(prev->on_cpu, 0);
where both p->sched_contributes_to_load and p->sched_remote_wakeup are
in the same word, and thus the stores X and Y race (and can clobber
one another's data).
Whereas prior to commit c6e7bd7afaeb ("sched/core: Optimize ttwu()
spinning on p->on_cpu") the p->on_cpu handoff serialized access to
p->sched_remote_wakeup (just as it still does with
p->sched_contributes_to_load) that commit broke that by calling
ttwu_queue_wakelist() with p->on_cpu != 0.
However, due to
p->XXX = X ttwu()
schedule() if (p->on_rq && ...) // false
smp_mb__after_spinlock() if (smp_load_acquire(&p->on_cpu) &&
deactivate_task() ttwu_queue_wakelist())
p->on_rq = 0; p->sched_remote_wakeup = Y;
We can be sure any 'current' store is complete and 'current' is
guaranteed asleep. Therefore we can move p->sched_remote_wakeup into
the current flags word.
Note: while the observed failure was loadavg accounting gone wrong due
to ttwu() cobbering p->sched_contributes_to_load, the reverse problem
is also possible where schedule() clobbers p->sched_remote_wakeup,
this could result in enqueue_entity() wrecking ->vruntime and causing
scheduling artifacts.
Fixes: c6e7bd7afaeb ("sched/core: Optimize ttwu() spinning on p->on_cpu")
Reported-by: Mel Gorman <mgorman@techsingularity.net>
Debugged-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201117083016.GK3121392@hirez.programming.kicks-ass.net
|
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iSCSI NOPs are sometimes "lost", mistakenly sent to the user-land iscsid
daemon instead of handled in the kernel, as they should be, resulting in a
message from the daemon like:
iscsid: Got nop in, but kernel supports nop handling.
This can occur because of the new forward- and back-locks, and the fact
that an iSCSI NOP response can occur before processing of the NOP send is
complete. This can result in "conn->ping_task" being NULL in
iscsi_nop_out_rsp(), when the pointer is actually in the process of being
set.
To work around this, we add a new state to the "ping_task" pointer. In
addition to NULL (not assigned) and a pointer (assigned), we add the state
"being set", which is signaled with an INVALID pointer (using "-1").
Link: https://lore.kernel.org/r/20201106193317.16993-1-leeman.duncan@gmail.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
|
|
Pull vhost fixes from Michael Tsirkin:
"Fixes all over the place, most notably vhost scsi IO error fixes"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost scsi: Add support for LUN resets.
vhost scsi: add lun parser helper
vhost scsi: fix cmd completion race
vhost scsi: alloc cmds per vq instead of session
vhost: add helper to check if a vq has been setup
vdpasim: fix "mac_pton" undefined error
swiotlb: using SIZE_MAX needs limits.h included
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|
Packets are processed even though the first fragment don't include all
headers through the upper layer header. This breaks TAHI IPv6 Core
Conformance Test v6LC.1.3.6.
Referring to RFC8200 SECTION 4.5: "If the first fragment does not include
all headers through an Upper-Layer header, then that fragment should be
discarded and an ICMP Parameter Problem, Code 3, message should be sent to
the source of the fragment, with the Pointer field set to zero."
The fragment needs to be validated the same way it is done in
commit 2efdaaaf883a ("IPv6: reply ICMP error if the first fragment don't
include all headers") for ipv6. Wrap the validation into a common function,
ipv6_frag_thdr_truncated() to check for truncation in the upper layer
header. This validation does not fullfill all aspects of RFC 8200,
section 4.5, but is at the moment sufficient to pass mentioned TAHI test.
In netfilter, utilize the fragment offset returned by find_prev_fhdr() to
let ipv6_frag_thdr_truncated() start it's traverse from the fragment
header.
Return 0 to drop the fragment in the netfilter. This is the same behaviour
as used on other protocol errors in this function, e.g. when
nf_ct_frag6_queue() returns -EPROTO. The Fragment will later be picked up
by ipv6_frag_rcv() in reassembly.c. ipv6_frag_rcv() will then send an
appropriate ICMP Parameter Problem message back to the source.
References commit 2efdaaaf883a ("IPv6: reply ICMP error if the first
fragment don't include all headers")
Signed-off-by: Georg Kohmann <geokohma@cisco.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/r/20201111115025.28879-1-geokohma@cisco.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
In many case, we need to check return value of pm_runtime_get_sync, but
it brings a trouble to the usage counter processing. Many callers forget
to decrease the usage counter when it failed, which could resulted in
reference leak. It has been discussed a lot[0][1]. So we add a function
to deal with the usage counter for better coding.
[0]https://lkml.org/lkml/2020/6/14/88
[1]https://patchwork.ozlabs.org/project/linux-tegra/list/?series=178139
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
"A set of fixes for perf:
- A set of commits which reduce the stack usage of various perf
event handling functions which allocated large data structs on
stack causing stack overflows in the worst case
- Use the proper mechanism for detecting soft interrupts in the
recursion protection
- Make the resursion protection simpler and more robust
- Simplify the scheduling of event groups to make the code more
robust and prepare for fixing the issues vs. scheduling of
exclusive event groups
- Prevent event multiplexing and rotation for exclusive event groups
- Correct the perf event attribute exclusive semantics to take
pinned events, e.g. the PMU watchdog, into account
- Make the anythread filtering conditional for Intel's generic PMU
counters as it is not longer guaranteed to be supported on newer
CPUs. Check the corresponding CPUID leaf to make sure
- Fixup a duplicate initialization in an array which was probably
caused by the usual 'copy & paste - forgot to edit' mishap"
* tag 'perf-urgent-2020-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Fix Add BW copypasta
perf/x86/intel: Make anythread filter support conditional
perf: Tweak perf_event_attr::exclusive semantics
perf: Fix event multiplexing for exclusive groups
perf: Simplify group_sched_in()
perf: Simplify group_sched_out()
perf/x86: Make dummy_iregs static
perf/arch: Remove perf_sample_data::regs_user_copy
perf: Optimize get_recursion_context()
perf: Fix get_recursion_context()
perf/x86: Reduce stack usage for x86_pmu::drain_pebs()
perf: Reduce stack usage of perf_output_begin()
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git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu
Pull percpu fix and cleanup from Dennis Zhou:
"A fix for a Wshadow warning in the asm-generic percpu macros came in
and then I tacked on the removal of flexible array initializers in the
percpu allocator"
* 'for-5.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
percpu: convert flexible array initializers to use struct_size()
asm-generic: percpu: avoid Wshadow warning
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Merge fixes from Andrew Morton:
"14 patches.
Subsystems affected by this patch series: mm (migration, vmscan, slub,
gup, memcg, hugetlbfs), mailmap, kbuild, reboot, watchdog, panic, and
ocfs2"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
ocfs2: initialize ip_next_orphan
panic: don't dump stack twice on warn
hugetlbfs: fix anon huge page migration race
mm: memcontrol: fix missing wakeup polling thread
kernel/watchdog: fix watchdog_allowed_mask not used warning
reboot: fix overflow parsing reboot cpu number
Revert "kernel/reboot.c: convert simple_strtoul to kstrtoint"
compiler.h: fix barrier_data() on clang
mm/gup: use unpin_user_pages() in __gup_longterm_locked()
mm/slub: fix panic in slab_alloc_node()
mailmap: fix entry for Dmitry Baryshkov/Eremin-Solenikov
mm/vmscan: fix NR_ISOLATED_FILE corruption on 64-bit
mm/compaction: stop isolation if too many pages are isolated and we have pages to migrate
mm/compaction: count pages and stop correctly during page isolation
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When we poll the swap.events, we can miss being woken up when the swap
event occurs. Because we didn't notify.
Fixes: f3a53a3a1e5b ("mm, memcontrol: implement memory.swap.events")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Yafang Shao <laoar.shao@gmail.com>
Cc: Chris Down <chris@chrisdown.name>
Cc: Tejun Heo <tj@kernel.org>
Link: https://lkml.kernel.org/r/20201105161936.98312-1-songmuchun@bytedance.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h
mutually exclusive") neglected to copy barrier_data() from
compiler-gcc.h into compiler-clang.h.
The definition in compiler-gcc.h was really to work around clang's more
aggressive optimization, so this broke barrier_data() on clang, and
consequently memzero_explicit() as well.
For example, this results in at least the memzero_explicit() call in
lib/crypto/sha256.c:sha256_transform() being optimized away by clang.
Fix this by moving the definition of barrier_data() into compiler.h.
Also move the gcc/clang definition of barrier() into compiler.h,
__memory_barrier() is icc-specific (and barrier() is already defined
using it in compiler-intel.h) and doesn't belong in compiler.h.
[rdunlap@infradead.org: fix ALPHA builds when SMP is not enabled]
Link: https://lkml.kernel.org/r/20201101231835.4589-1-rdunlap@infradead.org
Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive")
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20201014212631.207844-1-nivedita@alum.mit.edu
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Currently, we may set the tunnel option flag when the size of metadata
is zero. For example, we set TUNNEL_GENEVE_OPT in the receive function
no matter the geneve option is present or not. As this may result in
issues on the tunnel flags consumers, this patch fixes the issue.
Related discussion:
* https://lore.kernel.org/netdev/1604448694-19351-1-git-send-email-yihung.wei@gmail.com/T/#u
Fixes: 256c87c17c53 ("net: check tunnel option type in tunnel flags")
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Link: https://lore.kernel.org/r/1605053800-74072-1-git-send-email-yihung.wei@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Pull fs freeze fix and cleanups from Darrick Wong:
"A single vfs fix for 5.10, along with two subsequent cleanups.
A very long time ago, a hack was added to the vfs fs freeze protection
code to work around lockdep complaints about XFS, which would try to
run a transaction (which requires intwrite protection) to finalize an
xfs freeze (by which time the vfs had already taken intwrite).
Fast forward a few years, and XFS fixed the recursive intwrite problem
on its own, and the hack became unnecessary. Fast forward almost a
decade, and latent bugs in the code converting this hack from freeze
flags to freeze locks combine with lockdep bugs to make this reproduce
frequently enough to notice page faults racing with freeze.
Since the hack is unnecessary and causes thread race errors, just get
rid of it completely. Making this kind of vfs change midway through a
cycle makes me nervous, but a large enough number of the usual
VFS/ext4/XFS/btrfs suspects have said this looks good and solves a
real problem vector.
And once that removal is done, __sb_start_write is now simple enough
that it becomes possible to refactor the function into smaller,
simpler static inline helpers in linux/fs.h. The cleanup is
straightforward.
Summary:
- Finally remove the "convert to trylock" weirdness in the fs freezer
code. It was necessary 10 years ago to deal with nested
transactions in XFS, but we've long since removed that; and now
this is causing subtle race conditions when lockdep goes offline
and sb_start_* aren't prepared to retry a trylock failure.
- Minor cleanups of the sb_start_* fs freeze helpers"
* tag 'vfs-5.10-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
vfs: move __sb_{start,end}_write* to fs.h
vfs: separate __sb_start_write into blocking and non-blocking helpers
vfs: remove lockdep bogosity in __sb_start_write
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Pull block fixes from Jens Axboe:
"A few small fixes:
- NVMe pull request from Christoph:
- don't clear the read-only bit on a revalidate (Sagi Grimberg)
- nbd error case refcount leak (Christoph)
- loop/generic uevent fix (Christoph, Petr)"
* tag 'block-5.10-2020-11-13' of git://git.kernel.dk/linux-block:
loop: Fix occasional uevent drop
block: add a return value to set_capacity_revalidate_and_notify
nbd: fix a block_device refcount leak in nbd_release
nvme: fix incorrect behavior when BLKROSET is called by the user
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Commit 58956317c8de ("neighbor: Improve garbage collection")
guarantees neighbour table entries a five-second lifetime. Processes
which make heavy use of multicast can fill the neighour table with
multicast addresses in five seconds. At that point, neighbour entries
can't be GC-ed because they aren't five seconds old yet, the kernel
log starts to fill up with "neighbor table overflow!" messages, and
sends start to fail.
This patch allows multicast addresses to be thrown out before they've
lived out their five seconds. This makes room for non-multicast
addresses and makes messages to all addresses more reliable in these
circumstances.
Fixes: 58956317c8de ("neighbor: Improve garbage collection")
Signed-off-by: Jeff Dike <jdike@akamai.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20201113015815.31397-1-jdike@akamai.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO fixes from Linus Walleij:
"Some GPIO fixes I've collected with the help of Bartosz.
Nothing special about them: all are driver and kbuild fixes + some
documentation fixes:
- Tidy up a missed function call in the designware driver when
converting to gpiolib irqchip
- Fix some bitmasks in the Aspeed driver
- Fix some kerneldoc warnings and minor bugs in the improved
userspace API documentation
- Revert the revert of the OMAP fix for lost edge wakeup interrupts:
the fix needs to stay in
- Fix a compile error when deselecting the character device
- A bunch of IRQ fixes on the idio GPIO drivers
- Fix an off-by-one error in the SiFive GPIO driver"
* tag 'gpio-v5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: sifive: Fix SiFive gpio probe
gpio: pcie-idio-24: Enable PEX8311 interrupts
gpio: pcie-idio-24: Fix IRQ Enable Register value
gpio: pcie-idio-24: Fix irq mask when masking
gpiolib: fix sysfs when cdev is not selected
Revert "Revert "gpio: omap: Fix lost edge wake-up interrupts""
gpio: uapi: clarify the meaning of 'empty' char arrays
gpio: uapi: remove whitespace
gpio: uapi: kernel-doc formatting improvements
gpio: uapi: comment consistency
gpio: uapi: fix kernel-doc warnings
gpio: aspeed: fix ast2600 bank properties
gpio: dwapb: Fix missing conversion to GPIO-lib-based IRQ-chip
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Current release - regressions:
- arm64: dts: fsl-ls1028a-kontron-sl28: specify in-band mode for
ENETC
Current release - bugs in new features:
- mptcp: provide rmem[0] limit offset to fix oops
Previous release - regressions:
- IPv6: Set SIT tunnel hard_header_len to zero to fix path MTU
calculations
- lan743x: correctly handle chips with internal PHY
- bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE
- mlx5e: Fix VXLAN port table synchronization after function reload
Previous release - always broken:
- bpf: Zero-fill re-used per-cpu map element
- fix out-of-order UDP packets when forwarding with UDP GSO fraglists
turned on:
- fix UDP header access on Fast/frag0 UDP GRO
- fix IP header access and skb lookup on Fast/frag0 UDP GRO
- ethtool: netlink: add missing netdev_features_change() call
- net: Update window_clamp if SOCK_RCVBUF is set
- igc: Fix returning wrong statistics
- ch_ktls: fix multiple leaks and corner cases in Chelsio TLS offload
- tunnels: Fix off-by-one in lower MTU bounds for ICMP/ICMPv6 replies
- r8169: disable hw csum for short packets on all chip versions
- vrf: Fix fast path output packet handling with async Netfilter
rules"
* tag 'net-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (65 commits)
lan743x: fix use of uninitialized variable
net: udp: fix IP header access and skb lookup on Fast/frag0 UDP GRO
net: udp: fix UDP header access on Fast/frag0 UDP GRO
devlink: Avoid overwriting port attributes of registered port
vrf: Fix fast path output packet handling with async Netfilter rules
cosa: Add missing kfree in error path of cosa_write
net: switch to the kernel.org patchwork instance
ch_ktls: stop the txq if reaches threshold
ch_ktls: tcb update fails sometimes
ch_ktls/cxgb4: handle partial tag alone SKBs
ch_ktls: don't free skb before sending FIN
ch_ktls: packet handling prior to start marker
ch_ktls: Correction in middle record handling
ch_ktls: missing handling of header alone
ch_ktls: Correction in trimmed_len calculation
cxgb4/ch_ktls: creating skbs causes panic
ch_ktls: Update cheksum information
ch_ktls: Correction in finding correct length
cxgb4/ch_ktls: decrypted bit is not enough
net/x25: Fix null-ptr-deref in x25_connect
...
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Return if the function ended up sending an uevent or not.
Cc: stable@vger.kernel.org # v5.9
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Backchannel rpc tasks don't have task->tk_client set, so it's necessary
to check it for NULL before dereferencing.
Fixes: c509f15a5801 ("SUNRPC: Split the xdr_buf event class")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Make the intel_pstate driver behave as expected when it operates in
the passive mode with HWP enabled and the 'powersave' governor on top
of it"
* tag 'pm-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: intel_pstate: Take CPUFREQ_GOV_STRICT_TARGET into account
cpufreq: Add strict_target to struct cpufreq_policy
cpufreq: Introduce CPUFREQ_GOV_STRICT_TARGET
cpufreq: Introduce governor flags
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SPI driver probing currently comprises two steps, whereas removal
comprises only one step:
spi_alloc_master()
spi_register_controller()
spi_unregister_controller()
That's because spi_unregister_controller() calls device_unregister()
instead of device_del(), thereby releasing the reference on the
spi_controller which was obtained by spi_alloc_master().
An SPI driver's private data is contained in the same memory allocation
as the spi_controller struct. Thus, once spi_unregister_controller()
has been called, the private data is inaccessible. But some drivers
need to access it after spi_unregister_controller() to perform further
teardown steps.
Introduce devm_spi_alloc_master() and devm_spi_alloc_slave(), which
release a reference on the spi_controller struct only after the driver
has unbound, thereby keeping the memory allocation accessible. Change
spi_unregister_controller() to not release a reference if the
spi_controller was allocated by one of these new devm functions.
The present commit is small enough to be backportable to stable.
It allows fixing drivers which use the private data in their ->remove()
hook after it's been freed. It also allows fixing drivers which neglect
to release a reference on the spi_controller in the probe error path.
Long-term, most SPI drivers shall be moved over to the devm functions
introduced herein. The few that can't shall be changed in a treewide
commit to explicitly release the last reference on the controller.
That commit shall amend spi_unregister_controller() to no longer release
a reference, t |