Pull perf tools fixes from Arnaldo Carvalho de Melo:

- Revert "perf map: Fix dso->nsinfo refcounting", this makes 'perf top'
abort, uncovering a design flaw on how namespace information is kept.
The fix for that is more than we can do right now, leave it for the
next merge window.

- Split --dump-raw-trace by AUX records for ARM's CoreSight, fixing up
the decoding of some records.

- Fix PMU alias matching.

Thanks to James Clark and John Garry for these fixes.

* tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
Revert "perf map: Fix dso->nsinfo refcounting"
perf pmu: Fix alias matching
perf cs-etm: Split --dump-raw-trace by AUX records

Pull powerpc fixes from Michael Ellerman:

- Don't use r30 in VDSO code, to avoid breaking existing Go lang
programs.

- Change an export symbol to allow non-GPL modules to use spinlocks
again.

Thanks to Paul Menzel, and Srikar Dronamraju.

* tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/vdso: Don't use r30 to avoid breaking Go lang
powerpc/pseries: Fix regression while building external modules

This makes 'perf top' abort in some cases, and the right fix will
involve surgery that is too much to do at this stage, so revert for now
and fix it in the next merge window.

This reverts commit 2d6b74baa7147251c30a46c4996e8cc224aa2dc5.

Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull xfs fixes from Darrick Wong:
"This contains a bunch of bug fixes in XFS.

Dave and I have been busy the last couple of weeks to find and fix as
many log recovery bugs as we can find; here are the results so far. Go
fstests -g recoveryloop! ;)

- Fix a number of coordination bugs relating to cache flushes for
metadata writeback, cache flushes for multi-buffer log writes, and
FUA writes for single-buffer log writes

- Fix a bug with incorrect replay of attr3 blocks

- Fix unnecessary stalls when flushing logs to disk

- Fix spoofing problems when recovering realtime bitmap blocks"

* tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: prevent spoofing of rtbitmap blocks when recovering buffers
xfs: limit iclog tail updates
xfs: need to see iclog flags in tracing
xfs: Enforce attr3 buffer recovery order
xfs: logging the on disk inode LSN can make it go backwards
xfs: avoid unnecessary waits in xfs_log_force_lsn()
xfs: log forces imply data device cache flushes
xfs: factor out forced iclog flushes
xfs: fix ordering violation between cache flushes and tail updates
xfs: fold __xlog_state_release_iclog into xlog_state_release_iclog
xfs: external logs need to flush data device
xfs: flush data dev on external log write

The Go runtime uses r30 for some special value called 'g'. It assumes
that value will remain unchanged even when calling VDSO functions.
Although r30 is non-volatile across function calls, the callee is free
to use it, as long as the callee saves the value and restores it before
returning.

It used to be true by accident that the VDSO didn't use r30, because the
VDSO was hand-written asm. When we switched to building the VDSO from C
the compiler started using r30, at least in some builds, leading to
crashes in Go. eg:

~/go/src$ ./all.bash
Building Go cmd/dist using /usr/lib/go-1.16. (go1.16.2 linux/ppc64le)
Building Go toolchain1 using /usr/lib/go-1.16.
go build os/exec: /usr/lib/go-1.16/pkg/tool/linux_ppc64le/compile: signal: segmentation fault
go build reflect: /usr/lib/go-1.16/pkg/tool/linux_ppc64le/compile: signal: segmentation fault
go tool dist: FAILED: /usr/lib/go-1.16/bin/go install -gcflags=-l -tags=math_big_pure_go compiler_bootstrap bootstrap/cmd/...: exit status 1

There are patches in flight to fix Go[1], but until they are released
and widely deployed we can workaround it in the VDSO by avoiding use of
r30.

Note this only works with GCC, clang does not support -ffixed-rN.

1: https://go-review.googlesource.com/c/go/+/328110

Fixes: ab037dd87a2f ("powerpc/vdso: Switch VDSO to generic C implementation.")
Cc: stable@vger.kernel.org # v5.11+
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210729131244.2595519-1-mpe@ellerman.id.au

Commit c47a5599eda324ba ("perf tools: Fix pattern matching for same
substring in different PMU type"), may have fixed some alias matching,
but has broken some others.

Firstly it cannot handle the simple scenario of PMU name in form
pmu_name{digits} - it can only handle pmu_name_{digits}.

Secondly it cannot handle more complex matching in the case where we
have multiple tokens. In this scenario, the code failed to realise that
we may examine multiple substrings in the PMU name.

Fix in two ways:

- Change perf_pmu__valid_suffix() to accept a PMU name without '_' in the
suffix

- Only pay attention to perf_pmu__valid_suffix() for the final token

Also add const qualifiers as necessary to avoid casting.

Fixes: c47a5599eda324ba ("perf tools: Fix pattern matching for same substring in different PMU type")
Signed-off-by: John Garry <john.garry@huawei.com>
Tested-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/1626793819-79090-1-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull cifs fixes from Steve French:
"Three cifs/smb3 fixes, including two for stable, and a fix for an
fallocate problem noticed by Clang"

* tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: add missing parsing of backupuid
smb3: rc uninitialized in one fallocate path
SMB3: fix readpage for large swap cache

While reviewing the buffer item recovery code, the thought occurred to
me: in V5 filesystems we use log sequence number (LSN) tracking to avoid
replaying older metadata updates against newer log items. However, we
use the magic number of the ondisk buffer to find the LSN of the ondisk
metadata, which means that if an attacker can control the layout of the
realtime device precisely enough that the start of an rt bitmap block
matches the magic and UUID of some other kind of block, they can control
the purported LSN of that spoofed block and thereby break log replay.

Since realtime bitmap and summary blocks don't have headers at all, we
have no way to tell if a block really should be replayed. The best we
can do is replay unconditionally and hope for the best.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>

With commit c9f3401313a5 ("powerpc: Always enable queued spinlocks for
64s, disable for others") CONFIG_PPC_QUEUED_SPINLOCKS is always
enabled on ppc64le, external modules that use spinlock APIs are
failing.

ERROR: modpost: GPL-incompatible module XXX.ko uses GPL-only symbol 'shared_processor'

Before the above commit, modules were able to build without any
issues. Also this problem is not seen on other architectures. This
problem can be workaround if CONFIG_UNINLINE_SPIN_UNLOCK is enabled in
the config. However CONFIG_UNINLINE_SPIN_UNLOCK is not enabled by
default and only enabled in certain conditions like
CONFIG_DEBUG_SPINLOCKS is set in the kernel config.

#include <linux/module.h>
spinlock_t spLock;

static int __init spinlock_test_init(void)
{
spin_lock_init(&spLock);
spin_lock(&spLock);
spin_unlock(&spLock);
return 0;
}

static void __exit spinlock_test_exit(void)
{
printk("spinlock_test unloaded\n");
}
module_init(spinlock_test_init);
module_exit(spinlock_test_exit);

MODULE_DESCRIPTION ("spinlock_test");
MODULE_LICENSE ("non-GPL");
MODULE_AUTHOR ("Srikar Dronamraju");

Given that spin locks are one of the basic facilities for module code,
this effectively makes it impossible to build/load almost any non GPL
modules on ppc64le.

This was first reported at https://github.com/openzfs/zfs/issues/11172

Currently shared_processor is exported as GPL only symbol.
Fix this for parity with other architectures by exposing
shared_processor to non-GPL modules too.

Fixes: 14c73bd344da ("powerpc/vcpu: Assume dedicated processors as non-preempt")
Cc: stable@vger.kernel.org # v5.5+
Reported-by: marc.c.dionne@gmail.com
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210729060449.292780-1-srikar@linux.vnet.ibm.com

Currently --dump-raw-trace skips queueing and splitting buffers because
of an early exit condition in cs_etm__process_auxtrace_info(). Once
that is removed we can print the split data by using the queues
and searching for split buffers with the same reference as the
one that is currently being processed.

This keeps the same behaviour of dumping in file order when an AUXTRACE
event appears, rather than moving trace dump to where AUX records are in
the file.

There will be a newline and size printout for each fragment. For example
this buffer is comprised of two AUX records, but was printed as one:

0 0 0x8098 [0x30]: PERF_RECORD_AUXTRACE size: 0xa0 offset: 0 ref: 0x491a4dfc52fc0e6e idx: 0 t

. ... CoreSight ETM Trace data: size 160 bytes
Idx:0; ID:10; I_ASYNC : Alignment Synchronisation.
Idx:12; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 }
Idx:17; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0x0000000000000000;
Idx:80; ID:10; I_ASYNC : Alignment Synchronisation.
Idx:92; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 }
Idx:97; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0xFFFFDE2AD3FD76D4;

But is now printed as two fragments:

0 0 0x8098 [0x30]: PERF_RECORD_AUXTRACE size: 0xa0 offset: 0 ref: 0x491a4dfc52fc0e6e idx: 0 t

. ... CoreSight ETM Trace data: size 80 bytes
Idx:0; ID:10; I_ASYNC : Alignment Synchronisation.
Idx:12; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 }
Idx:17; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0x0000000000000000;

. ... CoreSight ETM Trace data: size 80 bytes
Idx:80; ID:10; I_ASYNC : Alignment Synchronisation.
Idx:92; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 }
Idx:97; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0xFFFFDE2AD3FD76D4;

Decoding errors that appeared in problematic files are now not present,
for example:

Idx:808; ID:1c; I_BAD_SEQUENCE : Invalid Sequence in packet.[I_ASYNC]
...
PKTP_ETMV4I_0016 : 0x0014 (OCSD_ERR_INVALID_PCKT_HDR) [Invalid packet header]; TrcIdx=822

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Al Grant <al.grant@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Branislav Rankov <branislav.rankov@arm.com>
Cc: Denis Nikitin <denik@chromium.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20210624164303.28632-3-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull networking fixes from Jakub Kicinski:
"Networking fixes for 5.14-rc4, including fixes from bpf, can, WiFi
(mac80211) and netfilter trees.

Current release - regressions:

- mac80211: fix starting aggregation sessions on mesh interfaces

Current release - new code bugs:

- sctp: send pmtu probe only if packet loss in Search Complete state

- bnxt_en: add missing periodic PHC overflow check

- devlink: fix phys_port_name of virtual port and merge error

- hns3: change the method of obtaining default ptp cycle

- can: mcba_usb_start(): add missing urb->transfer_dma initialization

Previous releases - regressions:

- set true network header for ECN decapsulation

- mlx5e: RX, avoid possible data corruption w/ relaxed ordering and
LRO

- phy: re-add check for PHY_BRCM_DIS_TXCRXC_NOENRGY on the BCM54811
PHY

- sctp: fix return value check in __sctp_rcv_asconf_lookup

Previous releases - always broken:

- bpf:
- more spectre corner case fixes, introduce a BPF nospec
instruction for mitigating Spectre v4
- fix OOB read when printing XDP link fdinfo
- sockmap: fix cleanup related races

- mac80211: fix enabling 4-address mode on a sta vif after assoc

- can:
- raw: raw_setsockopt(): fix raw_rcv panic for sock UAF
- j1939: j1939_session_deactivate(): clarify lifetime of session
object, avoid UAF
- fix number of identical memory leaks in USB drivers

- tipc:
- do not blindly write skb_shinfo frags when doing decryption
- fix sleeping in tipc accept routine"

* tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
gve: Update MAINTAINERS list
can: esd_usb2: fix memory leak
can: ems_usb: fix memory leak
can: usb_8dev: fix memory leak
can: mcba_usb_start(): add missing urb->transfer_dma initialization
can: hi311x: fix a signedness bug in hi3110_cmd()
MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver
bpf: Fix leakage due to insufficient speculative store bypass mitigation
bpf: Introduce BPF nospec instruction for mitigating Spectre v4
sis900: Fix missing pci_disable_device() in probe and remove
net: let flow have same hash in two directions
nfc: nfcsim: fix use after free during module unload
tulip: windbond-840: Fix missing pci_disable_device() in probe and remove
sctp: fix return value check in __sctp_rcv_asconf_lookup
nfc: s3fwrn5: fix undefined parameter values in dev_err()
net/mlx5: Fix mlx5_vport_tbl_attr chain from u16 to u32
net/mlx5e: Fix nullptr in mlx5e_hairpin_get_mdev()
net/mlx5: Unload device upon firmware fatal error
net/mlx5e: Fix page allocation failure for ptp-RQ over SF
net/mlx5e: Fix page allocation failure for trap-RQ over SF
...

We lost parsing of backupuid in the switch to new mount API.
Add it back.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: <stable@vger.kernel.org> # v5.11+
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

From the department of "generic/482 keeps on giving", we bring you
another tail update race condition:

iclog:
S1 C1
+-----------------------+-----------------------+
S2 EOIC

Two checkpoints in a single iclog. One is complete, the other just
contains the start record and overruns into a new iclog.

Timeline:

Before S1: Cache flush, log tail = X
At S1: Metadata stable, write start record and checkpoint
At C1: Write commit record, set NEED_FUA
Single iclog checkpoint, so no need for NEED_FLUSH
Log tail still = X, so no need for NEED_FLUSH

After C1,
Before S2: Cache flush, log tail = X
At S2: Metadata stable, write start record and checkpoint
After S2: Log tail moves to X+1
At EOIC: End of iclog, more journal data to write
Releases iclog
Not a commit iclog, so no need for NEED_FLUSH
Writes log tail X+1 into iclog.

At this point, the iclog has tail X+1 and NEED_FUA set. There has
been no cache flush for the metadata between X and X+1, and the
iclog writes the new tail permanently to the log. THis is sufficient
to violate on disk metadata/journal ordering.

We have two options here. The first is to detect this case in some
manner and ensure that the partial checkpoint write sets NEED_FLUSH
when the iclog is already marked NEED_FUA and the log tail changes.
This seems somewhat fragile and quite complex to get right, and it
doesn't actually make it obvious what underlying problem it is
actually addressing from reading the code.

The second option seems much cleaner to me, because it is derived
directly from the requirements of the C1 commit record in the iclog.
That is, when we write this commit record to the iclog, we've
guaranteed that the metadata/data ordering is correct for tail
update purposes. Hence if we only write the log tail into the iclog
for the *first* commit record rather than the log tail at the last
release, we guarantee that the log tail does not move past where the
the first commit record in the log expects it to be.

IOWs, taking the first option means that replay of C1 becomes
dependent on future operations doing the right thing, not just the
C1 checkpoint itself doing the right thing. This makes log recovery
almost impossible to reason about because now we have to take into
account what might or might not have happened in the future when
looking at checkpoints in the log rather than just having to
reconstruct the past...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Merge our fixes branch, which contains some fixes that didn't make it
into rc2 but which we'd like in next.

Pull ACPI fixes from Rafael Wysocki:
"These revert a recent IRQ resources handling modification that turned
out to be problematic, fix suspend-to-idle handling on AMD platforms
to take upcoming systems into account properly and fix the retrieval
of the DPTF attributes of the PCH FIVR.

Specifics:

- Revert recent change of the ACPI IRQ resources handling that
attempted to improve the ACPI IRQ override selection logic, but
introduced serious regressions on some systems (Hui Wang).

- Fix up quirks for AMD platforms in the suspend-to-idle support code
so as to take upcoming systems using uPEP HID AMDI007 into account
as appropriate (Mario Limonciello).

- Fix the code retrieving DPTF attributes of the PCH FIVR so that it
agrees on the return data type with the ACPI control method
evaluated for this purpose (Srinivas Pandruvada)"

* tag 'acpi-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: DPTF: Fix reading of attributes
Revert "ACPI: resources: Add checks for ACPI IRQ override"
ACPI: PM: Add support for upcoming AMD uPEP HID AMDI007

Marc Kleine-Budde says:

====================
pull-request: can 2021-07-30

The first patch is by me and adds Yasushi SHOJI as a reviewer for the
Microchip CAN BUS Analyzer Tool driver.

Dan Carpenter's patch fixes a signedness bug in the hi311x driver.

Pavel Skripkin provides 4 patches, the first targets the mcba_usb
driver by adding the missing urb->transfer_dma initialization, which
was broken in a previous commit. The last 3 patches fix a memory leak
in the usb_8dev, ems_usb and esd_usb2 driver.

* tag 'linux-can-fixes-for-5.14-20210730' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
can: esd_usb2: fix memory leak
can: ems_usb: fix memory leak
can: usb_8dev: fix memory leak
can: mcba_usb_start(): add missing urb->transfer_dma initialization
can: hi311x: fix a signedness bug in hi3110_cmd()
MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver
====================

Link: https://lore.kernel.org/r/20210730070526.1699867-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Clang detected a problem with rc possibly being unitialized
(when length is zero) in a recently added fallocate code path.

Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>

Because I cannot tell if the NEED_FLUSH flag is being set correctly
by the log force and CIL push machinery without it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

The H_ENTER_NESTED hypercall is handled by the L0, and it is a request
by the L1 to switch the context of the vCPU over to that of its L2
guest, and return with an interrupt indication. The L1 is responsible
for switching some registers to guest context, and the L0 switches
others (including all the hypervisor privileged state).

If the L2 MSR has TM active, then the L1 is responsible for
recheckpointing the L2 TM state. Then the L1 exits to L0 via the
H_ENTER_NESTED hcall, and the L0 saves the TM state as part of the exit,
and then it recheckpoints the TM state as part of the nested entry and
finally HRFIDs into the L2 with TM active MSR. Not efficient, but about
the simplest approach for something that's horrendously complicated.

Problems arise if the L1 exits to the L0 with a TM state which does not
match the L2 TM state being requested. For example if the L1 is
transactional but the L2 MSR is non-transactional, or vice versa. The
L0's HRFID can take a TM Bad Thing interrupt and crash.

Fix this by disallowing H_ENTER_NESTED in TM[T] state entirely, and then
ensuring that if the L1 is suspended then the L2 must have TM active,
and if the L1 is not suspended then the L2 must not have TM active.

Fixes: 360cae313702 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall")
Cc: stable@vger.kernel.org # v4.20+
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

gcc doesn't care, but clang quite reasonably pointed out that the recent
commit e9ba16e68cce ("smpboot: Mark idle_init() as __always_inlined to
work around aggressive compiler un-inlining") did some really odd
things:

kernel/smpboot.c:50:20: warning: duplicate 'inline' declaration specifier [-Wduplicate-decl-specifier]
static inline void __always_inline idle_init(unsigned int cpu)
^

which not only has that duplicate inlining specifier, but the new
__always_inline was put in the wrong place of the function definition.

We put the storage class specifiers (ie things like "static" and
"extern") first, and the type information after that. And while the
compiler may not care, we put the inline specifier before the types.

So it should be just

static __always_inline void idle_init(unsigned int cpu)

instead.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since commit 1b6b26ae7053 ("pipe: fix and clarify pipe write wakeup
logic") we have sanitized the pipe write logic, and would only try to
wake up readers if they needed it.

In particular, if the pipe already had data in it before the write,
there was no point in trying to wake up a reader, since any existing
readers must have been aware of the pre-existing data already. Doing
extraneous wakeups will only cause potential thundering herd problems.

However, it turns out that some Android libraries have misused the EPOLL
interface, and expected "edge triggered" be to "any new write will
trigger it". Even if there was no edge in sight.

Quoting Sandeep Patil:
"The commit 1b6b26ae7053 ('pipe: fix and clarify pipe write wakeup
logic') changed pipe write logic to wakeup readers only if the pipe
was empty at the time of write. However, there are libraries that
relied upon the older behavior for notification scheme similar to
what's described in [1]

One such library 'realm-core'[2] is used by numerous Android
applications. The library uses a similar notification mechanism as GNU
Make but it never drains the pipe until it is full. When Android moved
to v5.10 kernel, all applications using this library stopped working.

The library has since been fixed[3] but it will be a while before all
applications incorporate the updated library"

Our regression rule for the kernel is that if applications break from
new behavior, it's a regression, even if it was because the application
did something patently wrong. Also note the original report [4] by
Michal Kerrisk about a test for this epoll behavior - but at that point
we didn't know of any actual broken use case.

So add the extraneous wakeup, to approximate the old behavior.

[ I say "approximate", because the exact old behavior was to do a wakeup
not for each write(), but for each pipe buffer chunk that was filled
in. The behavior introduced by this change is not that - this is just
"every write will cause a wakeup, whether necessary or not", which
seems to be sufficient for the broken library use. ]

It's worth noting that this adds the extraneous wakeup only for the
write side, while the read side still considers the "edge" to be purely
about reading enough from the pipe to allow further writes.

See commit f467a6a66419 ("pipe: fix and clarify pipe read wakeup logic")
for the pipe read case, which remains that "only wake up if the pipe was
full, and we read something from it".

Link: https://lore.kernel.org/lkml/CAHk-=wjeG0q1vgzu4iJhW5juPkTsjTYmiqiMUYAebWW+0bam6w@mail.gmail.com/ [1]
Link: https://github.com/realm/realm-core [2]
Link: https://github.com/realm/realm-core/issues/4666 [3]
Link: https://lore.kernel.org/lkml/CAKgNAkjMBGeAwF=2MKK758BhxvW58wYTgYKB2V-gY1PwXxrH+Q@mail.gmail.com/ [4]
Link: https://lore.kernel.org/lkml/20210729222635.2937453-1-sspatil@android.com/
Reported-by: Sandeep Patil <sspatil@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* acpi-resources:
Revert "ACPI: resources: Add checks for ACPI IRQ override"

* acpi-dptf:
ACPI: DPTF: Fix reading of attributes

The team maintaining the gve driver has undergone some changes,
this updates the MAINTAINERS file accordingly.

Signed-off-by: Catherine Sullivan <csully@google.com>
Signed-off-by: Jon Olson <jonolson@google.com>
Signed-off-by: David Awogbemila <awogbemila@google.com>
Signed-off-by: Jeroen de Borst <jeroendb@google.com>
Link: https://lore.kernel.org/r/20210729155258.442650-1-csully@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

In esd_usb2_setup_rx_urbs() MAX_RX_URBS coherent buffers are allocated
and there is nothing, that frees them:

1) In callback function the urb is resubmitted and that's all
2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER
is not set (see esd_usb2_setup_rx_urbs) and this flag cannot be used
with coherent buffers.

So, all allocated buffers should be freed with usb_free_coherent()
explicitly.

Side note: This code looks like a copy-paste of other can drivers. The
same patch was applied to mcba_usb driver and it works nice with real
hardware. There is no change in functionality, only clean-up code for
coherent buffers.

Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
Link: https://lore.kernel.org/r/b31b096926dcb35998ad0271aac4b51770ca7cc8.1627404470.git.paskripkin@gmail.com
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

readpage was calculating the offset of the page incorrectly
for the case of large swapcaches.

loff_t offset = (loff_t)page->index << PAGE_SHIFT;

As pointed out by Matthew Wilcox, this needs to use
page_file_offset() to calculate the offset instead.
Pages coming from the swap cache have page->index set
to their index within the swapcache, not within the backing
file. For a sufficiently large swapcache, we could have
overlapping values of page->index within the same backing file.

Suggested by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org> # v5.7+
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

From the department of "WTAF? How did we miss that!?"...

When we are recovering a buffer, the first thing we do is check the
buffer magic number and extract the LSN from the buffer. If the LSN
is older than the current LSN, we replay the modification to it. If
the metadata on disk is newer than the transaction in the log, we
skip it. This is a fundamental v5 filesystem metadata recovery
behaviour.

generic/482 failed with an attribute writeback failure during log
recovery. The write verifier caught the corruption before it got
written to disk, and the attr buffer dump looked like:

XFS (dm-3): Metadata corruption detected at xfs_attr3_leaf_verify+0x275/0x2e0, xfs_attr3_leaf block 0x19be8
XFS (dm-3): Unmount and run xfs_repair
XFS (dm-3): First 128 bytes of corrupted metadata buffer:
00000000: 00 00 00 00 00 00 00 00 3b ee 00 00 4d 2a 01 e1 ........;...M*..
00000010: 00 00 00 00 00 01 9b e8 00 00 00 01 00 00 05 38 ...............8
^^^^^^^^^^^^^^^^^^^^^^^
00000020: df 39 5e 51 58 ac 44 b6 8d c5 e7 10 44 09 bc 17 .9^QX.D.....D...
00000030: 00 00 00 00 00 02 00 83 00 03 00 cc 0f 24 01 00 .............$..
00000040: 00 68 0e bc 0f c8 00 10 00 00 00 00 00 00 00 00 .h..............
00000050: 00 00 3c 31 0f 24 01 00 00 00 3c 32 0f 88 01 00 ..<1.$....<2....
00000060: 00 00 3c 33 0f d8 01 00 00 00 00 00 00 00 00 00 ..<3............
00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
.....

The highlighted bytes are the LSN that was replayed into the
buffer: 0x100000538. This is cycle 1, block 0x538. Prior to replay,
that block on disk looks like this:

$ sudo xfs_db -c "fsb 0x417d" -c "type attr3" -c p /dev/mapper/thin-vol
hdr.info.hdr.forw = 0
hdr.info.hdr.back = 0
hdr.info.hdr.magic = 0x3bee
hdr.info.crc = 0xb5af0bc6 (correct)
hdr.info.bno = 105448
hdr.info.lsn = 0x100000900
^^^^^^^^^^^
hdr.info.uuid = df395e51-58ac-44b6-8dc5-e7104409bc17
hdr.info.owner = 131203
hdr.count = 2
hdr.usedbytes = 120
hdr.firstused = 3796
hdr.holes = 1
hdr.freemap[0-2] = [base,size]

Note the LSN stamped into the buffer on disk: 1/0x900. The version
on disk is much newer than the log transaction that was being
replayed. That's a bug, and should -never- happen.

So I immediately went to look at xlog_recover_get_buf_lsn() to check
that we handled the LSN correctly. I was wondering if there was a
similar "two commits with the same start LSN skips the second
replay" problem with buffers. I didn't get that far, because I found
a much more basic, rudimentary bug: xlog_recover_get_buf_lsn()
doesn't recognise buffers with XFS_ATTR3_LEAF_MAGIC set in them!!!

IOWs, attr3 leaf buffers fall through the magic number checks
unrecognised, so trigger the "recover immediately" behaviour instead
of undergoing an LSN check. IOWs, we incorrectly replay ATTR3 leaf
buffers and that causes silent on disk corruption of inode attribute
forks and potentially other things....

Git history shows this is *another* zero day bug, this time
introduced in commit 50d5c8d8e938 ("xfs: check LSN ordering for v5
superblocks during recovery") which failed to handle the attr3 leaf
buffers in recovery. And we've failed to handle them ever since...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Pull perf tools fixes from Arnaldo Carvalho de Melo:

- Skip invalid hybrid PMU on hybrid systems when the atom (little) CPUs
are offlined.

- Fix 'perf test' problems related to the recently added hybrid
(BIG/little) code.

- Split ARM's coresight (hw tracing) decode by aux records to avoid
fatal decoding errors.

- Fix add event failure in 'perf probe' when running 32-bit perf in a
64-bit kernel.

- Fix 'perf sched record' failure when CONFIG_SCHEDSTATS is not set.

- Fix memory and refcount leaks detected by ASAn when running 'perf
test', should be clean of warnings now.

- Remove broken definition of __LITTLE_ENDIAN from tools'
linux/kconfig.h, which was breaking the build in some systems.

- Cast PTHREAD_STACK_MIN to int as it may turn into 'long
sysconf(__SC_THREAD_STACK_MIN_VALUE), breaking the build in some
systems.

- Fix libperf build error with LIBPFM4=1.

- Sync UAPI files changed by the memfd_secret new syscall.

* tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (35 commits)
perf sched: Fix record failure when CONFIG_SCHEDSTATS is not set
perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
perf data: Close all files in close_dir()
perf probe-file: Delete namelist in del_events() on the error path
perf test bpf: Free obj_buf
perf trace: Free strings in trace__parse_events_option()
perf trace: Free syscall tp fields in evsel->priv
perf trace: Free syscall->arg_fmt
perf trace: Free malloc'd trace fields on exit
perf lzma: Close lzma stream on exit
perf script: Fix memory 'threads' and 'cpus' leaks on exit
perf script: Release zstd data
perf session: Cleanup trace_event
perf inject: Close inject.output on exit
perf report: Free generated help strings for sort option
perf env: Fix memory leak of cpu_pmu_caps
perf test maps__merge_in: Fix memory leak of maps
perf dso: Fix memory leak in dso__new_map()
perf test event_update: Fix memory leak of unit
perf test event_update: Fix memory leak of evlist
...

The kvmppc_rtas_hcall() sets the host rtas_args.rets pointer based on
the rtas_args.nargs that was provided by the guest. That guest nargs
value is not range checked, so the guest can cause the host rets pointer
to be pointed outside the args array. The individual rtas function
handlers check the nargs and nrets values to ensure they are correct,
but if they are not, the handlers store a -3 (0xfffffffd) failure
indication in rets[0] which corrupts host memory.

Fix this by testing up front whether the guest supplied nargs and nret
would exceed the array size, and fail the hcall directly without storing
a failure indication to rets[0].

Also expand on a comment about why we kill the guest and try not to
return errors directly if we have a valid rets[0] pointer.

Fixes: 8e591cb72047 ("KVM: PPC: Book3S: Add infrastructure to implement kernel-side RTAS calls")
Cc: stable@vger.kernel.org # v3.10+
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Pull powerpc fixes from Michael Ellerman:

- Fix guest to host memory corruption in H_RTAS due to missing nargs
check.

- Fix guest triggerable host crashes due to bad handling of nested
guest TM state.

- Fix possible crashes due to incorrect reference counting in
kvm_arch_vcpu_ioctl().

- Two commits fixing some regressions in KVM transactional memory
handling introduced by the recent rework of the KVM code.

Thanks to Nicholas Piggin, Alexey Kardashevskiy, and Michael Neuling.

* tag 'powerpc-5.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
KVM: PPC: Book3S HV Nested: Sanitise H_ENTER_NESTED TM state
KVM: PPC: Book3S: Fix H_RTAS rets buffer overflow
KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak
KVM: PPC: Book3S: Fix CONFIG_TRANSACTIONAL_MEM=n crash
KVM: PPC: Book3S HV P9: Fix guest TM support

Pull block fixes from Jens Axboe:

- gendisk freeing fix (Christoph)

- blk-iocost wake ordering fix (Tejun)

- tag allocation error handling fix (John)

- loop locking fix. While this isn't the prettiest fix in the world,
nobody has any good alternatives for 5.14. Something to likely
revisit for 5.15. (Tetsuo)

* tag 'block-5.14-2021-07-30' of git://git.kernel.dk/linux-block:
block: delay freeing the gendisk
blk-iocost: fix operation ordering in iocg_wake_fn()
blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handling
loop: reintroduce global lock for safe loop_validate_file() traversal

AMD systems with uPEP HID AMDI007 should be using revision 2 and
the AMD method.

Fixes: 8fbd6c15ea0a ("ACPI: PM: Adjust behavior for field problems on AMD systems")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The commit 0ec4e55e9f57 ("ACPI: resources: Add checks for ACPI IRQ
override") introduces regression on some platforms, at least it makes
the UART can't get correct irq setting on two different platforms,
and it makes the kernel can't bootup on these two platforms.

This reverts commit 0ec4e55e9f571f08970ed115ec0addc691eda613.

Regression-discuss: https://bugzilla.kernel.org/show_bug.cgi?id=213031
Reported-by: PGNd <pgnet.dev@gmail.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The current assumption that methods to read PCH FIVR attributes will
return integer, is not correct. There is no good way to return integer
as negative numbers are also valid.

These read methods return a package of integers. The first integer returns
status, which is 0 on success and any other value for failure. When the
returned status is zero, then the second integer returns the actual value.

This change fixes this issue by replacing acpi_evaluate_integer() with
acpi_evaluate_object() and use acpi_extract_package() to extract results.

Fixes: 2ce6324eadb01 ("ACPI: DPTF: Add PCH FIVR participant driver")
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Daniel Borkmann says:

====================
pull-request: bpf 2021-07-29

The following pull-request contains BPF updates for your *net* tree.

We've added 9 non-merge commits during the last 14 day(s) which contain
a total of 20 files changed, 446 insertions(+), 138 deletions(-).

The main changes are:

1) Fix UBSAN out-of-bounds splat for showing XDP link fdinfo, from Lorenz Bauer.

2) Fix insufficient Spectre v4 mitigation in BPF runtime, from Daniel Borkmann,
Piotr Krysiuk and Benedict Schlueter.

3) Batch of fixes for BPF sockmap found under stress testing, from John Fastabend.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

In ems_usb_start() MAX_RX_URBS coherent buffers are allocated and
there is nothing, that frees them:

1) In callback function the urb is resubmitted and that's all
2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER
is not set (see ems_usb_start) and this flag cannot be used with
coherent buffers.

So, all allocated buffers should be freed with usb_free_coherent()
explicitly.

Side note: This code looks like a copy-paste of other can drivers. The
same patch was applied to mcba_usb driver and it works nice with real
hardware. There is no change in functionality, only clean-up code for
coherent buffers.

Fixes: 702171adeed3 ("ems_usb: Added support for EMS CPC-USB/ARM7 CAN/USB interface")
Link: https://lore.kernel.org/r/59aa9fbc9a8cbf9af2bbd2f61a659c480b415800.1627404470.git.paskripkin@gmail.com
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

When we log an inode, we format the "log inode" core and set an LSN
in that inode core. We do that via xfs_inode_item_format_core(),
which calls:

xfs_inode_to_log_dinode(ip, dic, ip->i_itemp->ili_item.li_lsn);

to format the log inode. It writes the LSN from the inode item into
the log inode, and if recovery decides the inode item needs to be
replayed, it recovers the log inode LSN field and writes it into the
on disk inode LSN field.

Now this might seem like a reasonable thing to do, but it is wrong
on multiple levels. Firstly, if the item is not yet in the AIL,
item->li_lsn is zero. i.e. the first time the inode it is logged and
formatted, the LSN we write into the log inode will be zero. If we
only log it once, recovery will run and can write this zero LSN into
the inode.

This means that the next time the inode is logged and log recovery
runs, it will *always* replay changes to the inode regardless of
whether the inode is newer on disk than the version in the log and
that violates the entire purpose of recording the LSN in the inode
at writeback time (i.e. to stop it going backwards in time on disk
during recovery).

Secondly, if we commit the CIL to the journal so the inode item
moves to the AIL, and then relog the inode, the LSN that gets
stamped into the log inode will be the LSN of the inode's current
location in the AIL, not it's age on disk. And it's not the LSN that
will be associated with the current change. That means when log
recovery replays this inode item, the LSN that ends up on disk is
the LSN for the previous changes in the log, not the current
changes being replayed. IOWs, after recovery the LSN on disk is not
in sync with the LSN of the modifications that were replayed into
the inode. This, again, violates the recovery ordering semantics
that on-disk writeback LSNs provide.

Hence the inode LSN in the log dinode is -always- invalid.

Thirdly, recovery actually has the LSN of the log transaction it is
replaying right at hand - it uses it to determine if it should
replay the inode by comparing it to the on-disk inode's LSN. But it
doesn't use that LSN to stamp the LSN into the inode which will be
written back when the transaction is fully replayed. It uses the one
in the log dinode, which we know is always going to be incorrect.

Looking back at the change history, the inode logging was broken by
commit 93f958f9c41f ("xfs: cull unnecessary icdinode fields") way
back in 2016 by a stupid idiot who thought he knew how this code
worked. i.e. me. That commit replaced an in memory di_lsn field that
was updated only at inode writeback time from the inode item.li_lsn
value - and hence always contained the same LSN that appeared in the
on-disk inode - with a read of the inode item LSN at inode format
time. CLearly these are not the same thing.

Before 93f958f9c41f, the log recovery behaviour was irrelevant,
because the LSN in the log inode always matched the on-disk LSN at
the time the inode was logged, hence recovery of the transaction
would never make the on-disk LSN in the inode go backwards or get
out of sync.

A symptom of the problem is this, caught from a failure of
generic/482. Before log recovery, the inode has been allocated but
never used:

xfs_db> inode 393388
xfs_db> p
core.magic = 0x494e
core.mode = 0
....
v3.crc = 0x99126961 (correct)
v3.change_count = 0
v3.lsn = 0
v3.flags2 = 0
v3.cowextsize = 0
v3.crtime.sec = Thu Jan 1 10:00:00 1970
v3.crtime.nsec = 0

After log recovery:

xfs_db> p
core.magic = 0x494e
core.mode = 020444
....
v3.crc = 0x23e68f23 (correct)
v3.change_count = 2
v3.lsn = 0
v3.flags2 = 0
v3.cowextsize = 0
v3.crtime.sec = Thu Jul 22 17:03:03 2021
v3.crtime.nsec = 751000000
...

You can see that the LSN of the on-disk inode is 0, even though it
clearly has been written to disk. I point out this inode, because
the generic/482 failure occurred because several adjacent inodes in
this specific inode cluster were not replayed correctly and still
appeared to be zero on disk when all the other metadata (inobt,
finobt, directories, etc) indicated they should be allocated and
written back.

The fix for this is two-fold. The first is that we need to either
revert the LSN changes in 93f958f9c41f or stop logging the inode LSN
altogether. If we do the former, log recovery does not need to
change but we add 8 bytes of memory per inode to store what is
largely a write-only inode field. If we do the latter, log recovery
needs to stamp the on-disk inode in the same manner that inode
writeback does.

I prefer the latter, because we shouldn't really be trying to log
and replay changes to the on disk LSN as the on-disk value is the
canonical source of the on-disk version of the inode. It also
matches the way we recover buffer items - we create a buf_log_item
that carries the current recovery transaction LSN that gets stamped
into the buffer by the write verifier when it gets written back
when the transaction is fully recovered.

However, this might break log recovery on older kernels even more,
so I'm going to simply ignore the logged value in recovery and stamp
the on-disk inode with the LSN of the transaction being recovered
that will trigger writeback on transaction recovery completion. This
will ensure that the on-disk inode LSN always reflects the LSN of
the last change that was written to disk, regardless of whether it
comes from log recovery or runtime writeback.

Fixes: 93f958f9c41f ("xfs: cull unnecessary icdinode fields")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Pull xfs fixes from Darrick Wong:
"A few fixes for issues in the new online shrink code, additional
corrections for my recent bug-hunt w.r.t. extent size hints on
realtime, and improved input checking of the GROWFSRT ioctl.

IOW, the usual 'I somehow got bored during the merge window and
resumed auditing the farther reaches of xfs':

- Fix shrink eligibility checking when sparse inode clusters enabled

- Reset '..' directory entries when unlinking directories to prevent
verifier errors if fs is shrinked later

- Don't report unusable extent size hints to FSGETXATTR

- Don't warn when extent size hints are unusable because the sysadmin
configured them that way

- Fix insufficient parameter validation in GROWFSRT ioctl

- Fix integer overflow when adding rt volumes to filesystem"

* tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: detect misaligned rtinherit directory extent size hints
xfs: fix an integer overflow error in xfs_growfs_rt
xfs: improve FSGROWFSRT precondition checking
xfs: don't expose misaligned extszinherit hints to userspace
xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
xfs: reset child dir '..' entry when unlinking child
xfs: check for sparse inode clusters that cross new EOAG when shrinking

The tracepoints trace_sched_stat_{wait, sleep, iowait} are not exposed to user
if CONFIG_SCHEDSTATS is not set, "perf sched record" records the three events.
As a result, the command fails.

Before:

#perf sched record sleep 1
event syntax error: 'sched:sched_stat_wait'
\___ unknown tracepoint

Error: File /sys/kernel/tracing/events/sched/sched_stat_wait not found.
Hint: Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

Run 'perf list' for a list of valid events

Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]

-e, --event <event> event selector. use 'perf list' to list available events

Solution:
Check whether schedstat tracepoints are exposed. If no, these events are not recorded.

After:
# perf sched record sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.163 MB perf.data (1091 samples) ]
# perf sched report
run measurement overhead: 4736 nsecs
sleep measurement overhead: 9059979 nsecs
the run test took 999854 nsecs
the sleep test took 8945271 nsecs
nr_run_events: 716
nr_sleep_events: 785
nr_wakeup_events: 0
...
------------------------------------------------------------

Fixes: 2a09b5de235a6 ("sched/fair: do not expose some tracepoints to user if CONFIG_SCHEDSTATS is not set")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Yafang Shao <laoar.shao@gmail.com>
Link: http://lore.kernel.org/lkml/20210713112358.194693-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

vcpu_put is not called if the user copy fails. This can result in preempt
notifier corruption and crashes, among other issues.

Fixes: b3cebfe8c1ca ("KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl")
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210716024310.164448-2-npiggin@gmail.com

Pull timer fixes from Thomas Gleixner:
"A small set of timer related fixes:

- Plug a race between rearm and process tick in the posix CPU timers
code

- Make the optimization to avoid recalculation of the next timer
interrupt work correctly when there are no timers pending"

* tag 'timers-urgent-2021-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Fix get_next_timer_interrupt() with no timers pending
posix-cpu-timers: Fix rearm racing against process tick

Pull io_uring fixes from Jens Axboe:

- A fix for block backed reissue (me)

- Reissue context hardening (me)

- Async link locking fix (Pavel)

* tag 'io_uring-5.14-2021-07-30' of git://git.kernel.dk/linux-block:
io_uring: fix poll requests leaking second poll entries
io_uring: don't block level reissue off completion path
io_uring: always reissue from task_work context
io_uring: fix race in unified task_work running
io_uring: fix io_prep_async_link locking

blkdev_get_no_open acquires a reference to the block_device through
the block device inode and then tries to acquire a device model
reference to the gendisk. But at this point the disk migh already
be freed (although the race is free). Fix this by only freeing the
gendisk from the whole device bdevs ->free_inode callback as well.

Fixes: 22ae8ce8b892 ("block: simplify bdev/disk lookup in blkdev_get")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210722075402.983367-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Replace pci_enable_device() with pcim_enable_device(),
pci_disable_device() and pci_release_regions() will be
called in release automatically.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Spectre v4 gadgets make use of memory disambiguation, which is a set of
techniques that execute memory access instructions, that is, loads and
stores, out of program order; Intel's optimization manual, section 2.4.4.5:

A load instruction micro-op may depend on a preceding store. Many
microarchitectures block loads until all preceding store addresses are
known. The memory disambiguator predicts which loads will not depend on
any previous stores. When the disambiguator predicts that a load does
not have such a dependency, the load takes its data from the L1 data
cache. Eventually, the prediction is verified. If an actual conflict is
detected, the load and all succeeding instructions are re-executed.

af86ca4e3088 ("bpf: Prevent memory disambiguation attack") tried to mitigate
this attack by sanitizing the memory locations through preemptive "fast"
(low latency) stores of zero prior to the actual "slow" (high latency) store
of a pointer value such that upon dependency misprediction the CPU then
speculatively executes the load of the pointer value and retrieves the zero
value instead of the attacker controlled scalar value previously stored at
that location, meaning, subsequent access in the speculative domain is then
redirected to the "zero page".

The sanitized preemptive store of zero prior to the actual "slow" store is
done through a simple ST instruction based on r10 (frame pointer) with
relative offset to the stack location that the verifier has been tracking
on the original used register for STX, which does not have to be r10. Thus,
there are no memory dependencies for this store, since it's only using r10
and immediate constant of zero; hence af86ca4e3088 /assumed/ a low latency
operation.

However, a recent attack demonstrated that this mitigation is not sufficient
since the preemptive store of zero could also be turned into a "slow" store
and is thus bypassed as well:

[...]
// r2 = oob address (e.g. scalar)
// r7 = pointer to map value
31: (7b) *(u64 *)(r10 -16) = r2
// r9 will remain "fast" register, r10 will become "slow" register below
32: (bf) r9 = r10
// JIT maps BPF reg to x86 reg:
// r9 -> r15 (callee saved)
// r10 -> rbp
// train store forward prediction to break dependency link between both r9
// and r10 by evicting them from the predictor's LRU table.
33: (61) r0 = *(u32 *)(r7 +24576)
34: (63) *(u32 *)(r7 +29696) = r0
35: (61) r0 = *(u32 *)(r7 +24580)
36: (63) *(u32 *)(r7 +29700) = r0
37: (61) r0 = *(u32 *)(r7 +24584)
38: (63) *(u32 *)(r7 +29704) = r0
39: (61) r0 = *(u32 *)(r7 +24588)
40: (63) *(u32 *)(r7 +29708) = r0
[...]
543: (61) r0 = *(u32 *)(r7 +25596)
544: (63) *(u32 *)(r7 +30716) = r0
// prepare call to bpf_ringbuf_output() helper. the latter will cause rbp
// to spill to stack memory while r13/r14/r15 (all callee saved regs) remain
// in hardware registers. rbp becomes slow due to push/pop latency. below is
// disasm of bpf_ringbuf_output() helper for better visual context:
//
// ffffffff8117ee20: 41 54 push r12
// ffffffff8117ee22: 55 push rbp
// ffffffff8117ee23: 53 push rbx
// ffffffff8117ee24: 48 f7 c1 fc ff ff ff test rcx,0xfffffffffffffffc
// ffffffff8117ee2b: 0f 85 af 00 00 00 jne ffffffff8117eee0 <-- jump taken
// [...]
// ffffffff8117eee0: 49 c7 c4 ea ff ff ff mov r12,0xffffffffffffffea
// ffffffff8117eee7: 5b pop rbx
// ffffffff8117eee8: 5d pop rbp
// ffffffff8117eee9: 4c 89 e0 mov rax,r12
// ffffffff8117eeec: 41 5c pop r12
// ffffffff8117eeee: c3 ret
545: (18) r1 = map[id:4]
547: (bf) r2 = r7
548: (b7) r3 = 0
549: (b7) r4 = 4
550: (85) call bpf_ringbuf_output#194288
// instruction 551 inserted by verifier \
551: (7a) *(u64 *)(r10 -16) = 0 | /both/ are now slow stores here
// storing map value pointer r7 at fp-16 | since value of r10 is "slow".
552: (7b) *(u64 *)(r10 -16) = r7 /
// following "fast" read to the same memory location, but due to dependency
// misprediction it will speculatively execute before insn 551/552 completes.
553: (79) r2 = *(u64 *)(r9 -16)
// in speculative domain contains attacker controlled r2. in non-speculative
// domain this contains r7, and thus accesses r7 +0 below.
554: (71) r3 = *(u8 *)(r2 +0)
// leak r3

As can be seen, the current speculative store bypass mitigation which the
verifier inserts at line 551 is insufficient since /both/, the write of
the zero sanitation as well as the map value pointer are a high latency
instruction due to prior memory access via push/pop of r10 (rbp) in contrast
to the low latency read in line 553 as r9 (r15) which stays in hardware
registers. Thus, architecturally, fp-16 is r7, however, microarchitecturally,
fp-16 can still be r2.

Initial thoughts to address this issue was to track spilled pointer loads
from stack and enforce their load via LDX through r10 as well so that /both/
the preemptive store of zero /as well as/ the load use the /same/ register
such that a dependency is created between the store and load. However, this
option is not sufficient either since it can be bypassed as well under
speculation. An updated attack with pointer spill/fills now _all_ based on
r10 would look as follows:

[...]
// r2 = oob address (e.g. scalar)
// r7 = pointer to map value
[...]
// longer store forward prediction training sequence than before.
2062: (61) r0 = *(u32 *)(r7 +25588)
2063: (63) *(u32 *)(r7 +30708) = r0
2064: (61) r0 = *(u32 *)(r7 +25592)
2065: (63) *(u32 *)(r7 +30712) = r0
2066: (61) r0 = *(u32 *)(r7 +25596)
2067: (63) *(u32 *)(r7 +30716) = r0
// store the speculative load address (scalar) this time after the store
// forward prediction training.
2068: (7b) *(u64 *)(r10 -16) = r2
// preoccupy the CPU store port by running sequence of dummy stores.
2069: (63) *(u32 *)(r7 +29696) = r0
2070: (63) *(u32 *)(r7 +29700) = r0
2071: (63) *(u32 *)(r7 +29704) = r0
2072: (63) *(u32 *)(r7 +29708) = r0
2073: (63) *(u32 *)(r7 +29712) = r0
2074: (63) *(u32 *)(r7 +29716) = r0
2075: (63) *(u32 *)(r7 +29720) = r0
2076: (63) *(u32 *)(r7 +29724) = r0
2077: (63) *(u32 *)(r7 +29728) = r0
2078: (63) *(u32 *)(r7 +29732) = r0
2079: (63) *(u32 *)(r7 +29736) = r0
2080: (63) *(u32 *)(r7 +29740) = r0
2081: (63) *(u32 *)(r7 +29744) = r0
2082: (63) *(u32 *)(r7 +29748) = r0
2083: (63) *(u32 *)(r7 +29752) = r0
2084: (63) *(u32 *)(r7 +29756) = r0
2085: (63) *(u32 *)(r7 +29760) = r0
2086: (63) *(u32 *)(r7 +29764) = r0
2087: (63) *(u32 *)(r7 +29768) = r0
2088: (63) *(u32 *)(r7 +29772) = r0
2089: (63) *(u32 *)(r7 +29776) = r0
2090: (63) *(u32 *)(r7 +29780) = r0
2091: (63) *(u32 *)(r7 +29784) = r0
2092: (63) *(u32 *)(r7 +29788) = r0
2093: (63) *(u32 *)(r7 +29792) = r0
2094: (63) *(u32 *)(r7 +29796) = r0
2095: (63) *(u32 *)(r7 +29800) = r0
2096: (63) *(u32 *)(r7 +29804) = r0
2097: (63) *(u32 *)(r7 +29808) = r0
2098: (63) *(u32 *)(r7 +29812) = r0
// overwrite scalar with dummy pointer; same as before, also including the
// sanitation store with 0 from the current mitigation by the verifier.
2099: (7a) *(u64 *)(r10 -16) = 0 | /both/ are now slow stores here
2100: (7b) *(u64 *)(r10 -16) = r7 | since store unit is still busy.
// load from stack intended to bypass stores.
2101: (79) r2 = *(u64 *)(r10 -16)
2102: (71) r3 = *(u8 *)(r2 +0)
// leak r3
[...]

Looking at the CPU microarchitecture, the scheduler might issue loads (such
as seen in line 2101) before stores (line 2099,2100) because the load execution
units become available while the store execution unit is still busy with the
sequence of dummy stores (line 2069-2098). And so the load may use the prior
stored scalar from r2 at address r10 -16 for speculation. The updated attack
may work less reliable on CPU microarchitectures where loads and stores share
execution resources.

This concludes that the sanitizing with zero stores from af86ca4e3088 ("bpf:
Prevent memory disambiguation attack") is insufficient. Moreover, the detection
of stack reuse from af86ca4e3088 where previously data (STACK_MISC) has been
written to a given stack slot where a pointer value is now to be stored does
not have sufficient coverage as precondition for the mitigation either; for
several reasons outlined as follows:

1) Stack content from prior program runs could still be preserved and is
therefore not "random", best example is to split a speculative store
bypass attack between tail calls, program A would prepare and store the
oob address at a given stack slot and then tail call into program B which
does the "slow" store of a pointer to the stack with subsequent "fast"
read. From program B PoV such stack slot type is STACK_INVALID, and
therefore also must be subject to mitigation.

2) The STACK_SPILL must not be coupled to register_is_const(&stack->spilled_ptr)
condition, for example, the previous content of that memory location could
also be a pointer to map or map value. Without the fix, a speculative
store bypass is not mitigated in such precondition and can then lead to
a type confusion in the speculative domain leaking kernel memory near
these pointer types.

While brainstorming on various alternative mitigation possibilities, we also
stumbled upon a retrospective from Chrome developers [0]:

[...] For variant 4, we implemented a mitigation to zero the unused memory
of the heap prior to allocation, which cost about 1% when done concurrently
and 4% for scavenging. Variant 4 defeats everything we could think of. We
explored more mitigations for variant 4 but the threat proved to be more
pervasive and dangerous than we anticipated. For example, stack slots used
by the register allocator in the optimizing compiler could be subject to
type confusion, leading to pointer crafting. Mitigating type confusion for
stack slots alone would have required a complete redesign of the backend of
the optimizing compiler, perhaps man years of work, without a guarantee of
completeness. [...]

From BPF side, the problem space is reduced, however, options are rather
limited. One idea that has been explored was to xor-obfuscate pointer spills
to the BPF stack:

[...]
// preoccupy the CPU store port by running sequence of dummy stores.
[...]
2106: (63) *(u32 *)(r7 +29796) = r0
2107: (63) *(u32 *)(r7 +29800) = r0
2108: (63) *(u32 *)(r7 +29804) = r0
2109: (63) *(u32 *)(r7 +29808) = r0
2110: (63) *(u32 *)(r7 +29812) = r0
// overwrite scalar with dummy pointer; xored with random 'secret' value
// of 943576462 before store ...
2111: (b4) w11 = 943576462
2112: (af) r11 ^= r7
2113: (7b) *(u64 *)(r10 -16) = r11
2114: (79) r11 = *(u64 *)(r10 -16)
2115: (b4) w2 = 943576462
2116: (af) r2 ^= r11
// ... and restored with the same 'secret' value with the help of AX reg.
2117: (71) r3 = *(u8 *)(r2 +0)
[...]

While the above would not prevent speculation, it would make data leakage
infeasible by directing it to random locations. In order to be effective
and prevent type confusion under speculation, such random secret would have
to be regenerated for each store. The additional complexity involved for a
tracking mechanism that prevents jumps such that restoring spilled pointers
would not get corrupted is not worth the gain for unprivileged. Hence, the
fix in here eventually opted for emitting a non-public BPF_ST | BPF_NOSPEC
instruction which the x86 JIT translates into a lfence opcode. Inserting the
latter in between the store and load instruction is one of the mitigations
options [1]. The x86 instruction manual notes:

[...] An LFENCE that follows an instruction that stores to memory might
complete before the data being stored have become globally visible. [...]

The latter meaning that the preceding store instruction finished execution
and the store is at minimum guaranteed to be in the CPU's store queue, but
it's not guaranteed to be in that CPU's L1 cache at that point (globally
visible). The latter would only be guaranteed via sfence. So the load which
is guaranteed to execute after the lfence for that local CPU would have to
rely on store-to-load forwarding. [2], in section 2.3 on store buffers says:

[...] For every store operation that is added to the ROB, an entry is
allocated in the store buffer. This entry requires both the virtual and
physical address of the target. Only if there is no free entry in the store
buffer, the frontend stalls until there is an empty slot available in the
store buffer again. Otherwise, the CPU can immediately continue adding
subsequent instructions to the ROB and execute them out of order. On Intel
CPUs, the store buffer has up to 56 entries. [...]

One small upside on the fix is that it lifts constraints from af86ca4e3088
where the sanitize_stack_off relative to r10 must be the same when coming
from different paths. The BPF_ST | BPF_NOSPEC gets emitted after a BPF_STX
or BPF_ST instruction. This happens either when we store a pointer or data
value to the BPF stack for the first time, or upon later pointer spills.
The former needs to be enforced since otherwise stale stack data could be
leaked under speculation as outlined earlier. For non-x86 JITs the BPF_ST |
BPF_NOSPEC mapping is currently optimized away, but others could emit a
speculation barrier as well if necessary. For real-world unprivileged
programs e.g. generated by LLVM, pointer spill/fill is only generated upon
register pressure and LLVM only tries to do that for pointers which are not
used often. The program main impact will be the initial BPF_ST | BPF_NOSPEC
sanitation for the STACK_INVALID case when the first write to a stack slot
occurs e.g. upon map lookup. In future we might refine ways to mitigate
the latter cost.

[0] https://arxiv.org/pdf/1902.05178.pdf
[1] https://msrc-blog.microsoft.com/2018/05/21/analysis-and-mitigation-of-speculative-store-bypass-cve-2018-3639/
[2] https://arxiv.org/pdf/1905.05725.pdf

Fixes: af86ca4e3088 ("bpf: Prevent memory disambiguation attack")
Fixes: f7cf25b2026d ("bpf: track spill/fill of constants")
Co-developed-by: Piotr Krysiuk <piotras@gmail.com>
Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>

In usb_8dev_start() MAX_RX_URBS coherent buffers are allocated and
there is nothing, that frees them:

1) In callback function the urb is resubmitted and that's all
2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER
is not set (see usb_8dev_start) and this flag cannot be used with
coherent buffers.

So, all allocated buffers should be freed with usb_free_coherent()
explicitly.

Side note: This code looks like a copy-paste of other can drivers. The
same patch was applied to mcba_usb driver and it works nice with real
hardware. There is no change in functionality, only clean-up code for
coherent buffers.

Fixes: 0024d8ad1639 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices")
Link: https://lore.kernel.org/r/d39b458cd425a1cf7f512f340224e6e9563b07bd.1627404470.git.paskripkin@gmail.com
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Before waiting on a iclog in xfs_log_force_lsn(), we don't check to
see if the iclog has already been completed and the contents on
stable storage. We check for completed iclogs in xfs_log_force(), so
we should do the same thing for xfs_log_force_lsn().

This fixed some random up-to-30s pauses seen in unmounting
filesystems in some tests. A log force ends up waiting on completed
iclog, and that doesn't then get flushed (and hence the log force
get completed) until the background log worker issues a log force
that flushes the iclog in question. Then the unmount unblocks and
continues.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Pull iomap fixes from Darrick Wong:
"A handful of bugfixes for the iomap code.

There's nothing especially exciting here, just fixes for UBSAN (not
KASAN as I erroneously wrote in the tag message) warnings about
undefined behavior in the SEEK_DATA/SEEK_HOLE code, and some
reshuffling of per-page block state info to fix some problems with
gfs2.

- Fix KASAN warnings due to integer overflow in SEEK_DATA/SEEK_HOLE

- Fix assertion errors when using inlinedata files on gfs2"

* tag 'iomap-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: Don't create iomap_page objects in iomap_page_mkwrite_actor
iomap: Don't create iomap_page objects for inline files
iomap: Permit pages without an iop to enter writeback
iomap: remove the length variable in iomap_seek_hole
iomap: remove the length variable in iomap_seek_data

If we encounter a directory that has been configured to pass on an
extent size hint to a new realtime file and the hint isn't an integer
multiple of the rt extent size, we should flag the hint for
administrative review because that is a misconfiguration (that other
parts of the kernel will fix automatically).

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

The "address" member of "struct probe_trace_point" uses long data type.
If kernel is 64-bit and perf program is 32-bit, size of "address"
variable is 32 bits.

As a result, upper 32 bits of address read from kernel are truncated, an
error occurs during address comparison in kprobe_warn_out_range().

Before:

# perf probe -a schedule
schedule is out of .text, skip it.
Error: Failed to add events.

Solution:
Change data type of "address" variable to u64 and change corresponding
address printing and value assignment.

After:

# perf.new.new probe -a schedule
Added new event:
probe:schedule (on schedule)

You can now use it in all perf tools, such as:

perf record -e probe:schedule -aR sleep 1

# perf probe -l
probe:schedule (on schedule@kernel/sched/core.c)
# perf record -e probe:schedule -aR sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
# perf report --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 1K of event 'probe:schedule'
# Event count (approx.): 1366
#
# Overhead Command Shared Object Symbol
# ........ ............... ................. ............
#
6.22% migration/0 [kernel.kallsyms] [k] schedule
6.22% migration/1 [kernel.kallsyms] [k] schedule
6.22% migration/2 [kernel.kallsyms] [k] schedule
6.22% migration/3 [kernel.kallsyms] [k] schedule
6.15% migration/10 [kernel.kallsyms] [k] schedule
6.15% migration/11 [kernel.kallsyms] [k] schedule
6.15% migration/12 [kernel.kallsyms] [k] schedule
6.15% migration/13 [kernel.kallsyms] [k] schedule
6.15% migration/14 [kernel.kallsyms] [k] schedule
6.15% migration/15 [kernel.kallsyms] [k] schedule
6.15% migration/4 [kernel.kallsyms] [k] schedule
6.15% migration/5 [kernel.kallsyms] [k] schedule
6.15% migration/6 [kernel.kallsyms] [k] schedule
6.15% migration/7 [kernel.kallsyms] [k] schedule
6.15% migration/8 [kernel.kallsyms] [k] schedule
6.15% migration/9 [kernel.kallsyms] [k] schedule
0.22% rcu_sched [kernel.kallsyms] [k] schedule
...
#
# (Cannot load tips.txt file, please install perf!)
#

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jianlin Lv <jianlin.lv@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When running CPU_FTR_P9_TM_HV_ASSIST, HFSCR[TM] is set for the guest
even if the host has CONFIG_TRANSACTIONAL_MEM=n, which causes it to be
unprepared to handle guest exits while transactional.

Normal guests don't have a problem because the HTM capability will not
be advertised, but a rogue or buggy one could crash the host.

Fixes: 4bb3c7a0208f ("KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9")
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210716024310.164448-1-npiggin@gmail.com

Pull x86 jump label fix from Thomas Gleixner:
"A single fix for jump labels to prevent the compiler from agressive
un-inlining which results in a section mismatch"

* tag 'locking-urgent-2021-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
jump_labels: Mark __jump_label_transform() as __always_inlined to work around aggressive compiler un-inlining

Pull dyntick fixes from Frederic Weisbecker:

- Fix a rearm race in the posix cpu timer code
- Handle get_next_timer_interrupt() correctly when no timers are pending

Link: https://lore.kernel.org/r/20210715104218.81276-1-frederic@kernel.org

Pull libata fixlets from Jens Axboe:

- A fix for PIO highmem (Christoph)

- Kill HAVE_IDE as it's now unused (Lukas)

* tag 'libata-5.14-2021-07-30' of git://git.kernel.dk/linux-block:
arch: Kconfig: clean up obsolete use of HAVE_IDE
libata: fix ata_pio_sector for CONFIG_HIGHMEM

For pure poll requests, it doesn't remove the second poll wait entry
when it's done, neither after vfs_poll() or in the poll completion
handler. We should remove the second poll wait entry.
And we use io_poll_remove_double() rather than io_poll_remove_waitqs()
since the latter has some redundant logic.

Fixes: 88e41cf928a6 ("io_uring: add multishot mode for IORING_OP_POLL_ADD")
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20210728030322.12307-1-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

iocg_wake_fn() open-codes wait_queue_entry removal and wakeup because it
wants the wq_entry to be always removed whether it ended up waking the
task or not. finish_wait() tests whether wq_entry needs removal without
grabbing the wait_queue lock and expects the waker to use
list_del_init_careful() after all waking operations are complete, which
iocg_wake_fn() didn't do. The operation order was wrong and the regular
list_del_init() was used.

The result is that if a waiter wakes up racing the waker, it can free pop
the wq_entry off stack before the waker is still looking at it, which can
lead to a backtrace like the following.

[7312084.588951] general protection fault, probably for non-canonical address 0x586bf4005b2b88: 0000 [#1] SMP
...
[7312084.647079] RIP: 0010:queued_spin_lock_slowpath+0x171/0x1b0
...
[7312084.858314] Call Trace:
[7312084.863548] _raw_spin_lock_irqsave+0x22/0x30
[7312084.872605] try_to_wake_up+0x4c/0x4f0
[7312084.880444] iocg_wake_fn+0x71/0x80
[7312084.887763] __wake_up_common+0x71/0x140
[7312084.895951] iocg_kick_waitq+0xe8/0x2b0
[7312084.903964] ioc_rqos_throttle+0x275/0x650
[7312084.922423] __rq_qos_throttle+0x20/0x30
[7312084.930608] blk_mq_make_request+0x120/0x650
[7312084.939490] generic_make_request+0xca/0x310
[7312084.957600] submit_bio+0x173/0x200
[7312084.981806] swap_readpage+0x15c/0x240
[7312084.989646] read_swap_cache_async+0x58/0x60
[7312084.998527] swap_cluster_readahead+0x201/0x320
[7312085.023432] swapin_readahead+0x2df/0x450
[7312085.040672] do_swap_page+0x52f/0x820
[7312085.058259] handle_mm_fault+0xa16/0x1420
[7312085.066620] do_page_fault+0x2c6/0x5c0
[7312085.074459] page_fault+0x2f/0x40

Fix it by switching to list_del_init_careful() and putting it at the end.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Rik van Riel <riel@surriel.com>
Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Jens Axboe <axboe@kernel.dk>

using same source and destination ip/port for flow hash calculation
within the two directions.

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>