Return if the function ended up sending an uevent or not.

Cc: stable@vger.kernel.org # v5.9
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NPetr Vorel <pvorel@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arraysSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

No one checks the return value of debugfs_create_devm_seqfile(), as it's
not needed, so make the return value void, so that no one tries to do so
in the future.

Link: https://lore.kernel.org/r/20201023131037.2500765-1-gregkh@linuxfoundation.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arraysSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arraysSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arraysSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arraysSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arraysSigned-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

In preparation to enable -Wimplicit-fallthrough for Clang, explicitly
add break statements instead of letting the code fall through to the
next case.

This patch adds four break statements that, together, fix almost 40,000
warnings when building Linux 5.10-rc1 with Clang 12.0.0 and this[1] change
reverted. Notice that in order to enable -Wimplicit-fallthrough for Clang,
such change[1] is meant to be reverted at some point. So, this patch helps
to move in that direction.

Something important to mention is that there is currently a discrepancy
between GCC and Clang when dealing with switch fall-through to empty case
statements or to cases that only contain a break/continue/return
statement[2][3][4].

Now that the -Wimplicit-fallthrough option has been globally enabled[5],
any compiler should really warn on missing either a fallthrough annotation
or any of the other case-terminating statements (break/continue/return/
goto) when falling through to the next case statement. Making exceptions
to this introduces variation in case handling which may continue to lead
to bugs, misunderstandings, and a general lack of robustness. The point
of enabling options like -Wimplicit-fallthrough is to prevent human error
and aid developers in spotting bugs before their code is even built/
submitted/committed, therefore eliminating classes of bugs. So, in order
to really accomplish this, we should, and can, move in the direction of
addressing any error-prone scenarios and get rid of the unintentional
fallthrough bug-class in the kernel, entirely, even if there is some minor
redundancy. Better to have explicit case-ending statements than continue to
have exceptions where one must guess as to the right result. The compiler
will eliminate any actual redundancy.

[1] commit e2079e93 ("kbuild: Do not enable -Wimplicit-fallthrough for clang for now")
[2] https://github.com/ClangBuiltLinux/linux/issues/636
[3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91432
[4] https://godbolt.org/z/xgkvIh
[5] commit a035d552 ("Makefile: Globally enable fall-through warning")
Co-developed-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>

Fix afs_invalidatepage() to adjust the dirty region recorded in
page->private when truncating a page.  If the dirty region is entirely
removed, then the private data is cleared and the page dirty state is
cleared.

Without this, if the page is truncated and then expanded again by truncate,
zeros from the expanded, but no-longer dirty region may get written back to
the server if the page gets laundered due to a conflicting 3rd-party write.

It mustn't, however, shorten the dirty region of the page if that page is
still mmapped and has been marked dirty by afs_page_mkwrite(), so a flag is
stored in page->private to record this.

Fixes: 4343d008 ("afs: Get rid of the afs_writeback record")
Signed-off-by: NDavid Howells <dhowells@redhat.com>

The afs filesystem uses page->private to store the dirty range within a
page such that in the event of a conflicting 3rd-party write to the server,
we write back just the bits that got changed locally.

However, there are a couple of problems with this:

 (1) I need a bit to note if the page might be mapped so that partial
     invalidation doesn't shrink the range.

 (2) There aren't necessarily sufficient bits to store the entire range of
     data altered (say it's a 32-bit system with 64KiB pages or transparent
     huge pages are in use).

So wrap the accesses in inline functions so that future commits can change
how this works.

Also move them out of the tracing header into the in-directory header.
There's not really any need for them to be in the tracing header.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Add a helper function to test the flags of the cpufreq driver in use
againt a given flags mask.

In particular, this will be needed to test the
CPUFREQ_NEED_UPDATE_LIMITS cpufreq driver flag in the schedutil
governor.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch removes the MIC drivers from the kernel tree
since the corresponding devices have been discontinued.

Removing the dma and char-misc changes in one patch and
merging via the char-misc tree is best to avoid any
potential build breakage.

Cc: Nikhil Rao <nikhil.rao@intel.com>
Reviewed-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NSudeep Dutt <sudeep.dutt@intel.com>
Acked-By: NVinod Koul <vkoul@kernel.org>
Reviewed-by: NSherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/8c1443136563de34699d2c084df478181c205db4.1603854416.git.sudeep.dutt@intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The kernel-doc markup that documents _fc_replay_callback is
missing an asterisk, causing this warning:

	../include/linux/jbd2.h:1271: warning: Function parameter or member 'j_fc_replay_callback' not described in 'journal_s'

When building the docs.

Fixes: 609f928af48f ("jbd2: fast commit recovery path")
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6055927ada2015b55b413cdd2670533bdc9a8da2.1603791716.git.mchehab+huawei@kernel.orgSigned-off-by: NTheodore Ts'o <tytso@mit.edu>

This patch reserves a field in the jbd2 superblock for number of fast
commit blocks. When this value is non-zero, Ext4 uses this field to
set the number of fast commit blocks.

Fixes: 6866d7b3 ("ext4/jbd2: add fast commit initialization")
Signed-off-by: NHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201027044915.2553163-2-harshadshirwadkar@gmail.comSigned-off-by: NTheodore Ts'o <tytso@mit.edu>

Geert reports that commit be288182 ("arm64/build: Assert for
unwanted sections") results in build errors on arm64 for configurations
that have CONFIG_MODULES disabled.

The commit in question added ASSERT()s to the arm64 linker script to
ensure that linker generated sections such as .got.plt etc are empty,
but as it turns out, there are corner cases where the linker does emit
content into those sections. More specifically, weak references to
function symbols (which can remain unsatisfied, and can therefore not
be emitted as relative references) will be emitted as GOT and PLT
entries when linking the kernel in PIE mode (which is the case when
CONFIG_RELOCATABLE is enabled, which is on by default).

What happens is that code such as

	struct device *(*fn)(struct device *dev);
	struct device *iommu_device;

	fn = symbol_get(mdev_get_iommu_device);
	if (fn) {
		iommu_device = fn(dev);

essentially gets converted into the following when CONFIG_MODULES is off:

	struct device *iommu_device;

	if (&mdev_get_iommu_device) {
		iommu_device = mdev_get_iommu_device(dev);

where mdev_get_iommu_device is emitted as a weak symbol reference into
the object file. The first reference is decorated with an ordinary
ABS64 data relocation (which yields 0x0 if the reference remains
unsatisfied). However, the indirect call is turned into a direct call
covered by a R_AARCH64_CALL26 relocation, which is converted into a
call via a PLT entry taking the target address from the associated
GOT entry.

Given that such GOT and PLT entries are unnecessary for fully linked
binaries such as the kernel, let's give these weak symbol references
hidden visibility, so that the linker knows that the weak reference
via R_AARCH64_CALL26 can simply remain unsatisfied.
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>
Tested-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NFangrui Song <maskray@google.com>
Acked-by: NJessica Yu <jeyu@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20201027151132.14066-1-ardb@kernel.orgSigned-off-by: NWill Deacon <will@kernel.org>

There is a common comment marked, instead, with kernel-doc
notation.

Also, some identifiers have different names between their
prototypes and the kernel-doc markup.
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: NFelipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/0b964be3884def04fcd20ea5c12cb90d0014871c.1603469755.git.mchehab+huawei@kernel.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are two flows for handling RDMA_CM_EVENT_ROUTE_RESOLVED, either the
handler triggers a completion and another thread does rdma_connect() or
the handler directly calls rdma_connect().

In all cases rdma_connect() needs to hold the handler_mutex, but when
handler's are invoked this is already held by the core code. This causes
ULPs using the 2nd method to deadlock.

Provide a rdma_connect_locked() and have all ULPs call it from their
handlers.

Link: https://lore.kernel.org/r/0-v2-53c22d5c1405+33-rdma_connect_locking_jgg@nvidia.comReported-and-tested-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Fixes: 2a7cec53 ("RDMA/cma: Fix locking for the RDMA_CM_CONNECT state")
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: NJack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMax Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>

According to the SMCCC spec[1](7.5.2 Discovery) the
ARM_SMCCC_ARCH_WORKAROUND_1 function id only returns 0, 1, and
SMCCC_RET_NOT_SUPPORTED.

 0 is "workaround required and safe to call this function"
 1 is "workaround not required but safe to call this function"
 SMCCC_RET_NOT_SUPPORTED is "might be vulnerable or might not be, who knows, I give up!"

SMCCC_RET_NOT_SUPPORTED might as well mean "workaround required, except
calling this function may not work because it isn't implemented in some
cases". Wonderful. We map this SMC call to

 0 is SPECTRE_MITIGATED
 1 is SPECTRE_UNAFFECTED
 SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE

For KVM hypercalls (hvc), we've implemented this function id to return
SMCCC_RET_NOT_SUPPORTED, 0, and SMCCC_RET_NOT_REQUIRED. One of those
isn't supposed to be there. Per the code we call
arm64_get_spectre_v2_state() to figure out what to return for this
feature discovery call.

 0 is SPECTRE_MITIGATED
 SMCCC_RET_NOT_REQUIRED is SPECTRE_UNAFFECTED
 SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE

Let's clean this up so that KVM tells the guest this mapping:

 0 is SPECTRE_MITIGATED
 1 is SPECTRE_UNAFFECTED
 SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE

Note: SMCCC_RET_NOT_AFFECTED is 1 but isn't part of the SMCCC spec

Fixes: c118bbb5 ("arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests")
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Acked-by: NMarc Zyngier <maz@kernel.org>
Acked-by: NWill Deacon <will@kernel.org>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://developer.arm.com/documentation/den0028/latest [1]
Link: https://lore.kernel.org/r/20201023154751.1973872-1-swboyd@chromium.orgSigned-off-by: NWill Deacon <will@kernel.org>

Under some circumstances, the compiler generates .ctors.* sections. This
is seen doing a cross compile of x86_64 from a powerpc64el host:

x86_64-linux-gnu-ld: warning: orphan section `.ctors.65435' from `kernel/trace/trace_clock.o' being
placed in section `.ctors.65435'
x86_64-linux-gnu-ld: warning: orphan section `.ctors.65435' from `kernel/trace/ftrace.o' being
placed in section `.ctors.65435'
x86_64-linux-gnu-ld: warning: orphan section `.ctors.65435' from `kernel/trace/ring_buffer.o' being
placed in section `.ctors.65435'

Include these orphans along with the regular .ctors section.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Tested-by: NStephen Rothwell <sfr@canb.auug.org.au>
Fixes: 83109d5d ("x86/build: Warn on orphan section placement")
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NNick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20201005025720.2599682-1-keescook@chromium.org

Generally, a cpufreq driver may need to update some internal upper
and lower frequency boundaries on policy max and min changes,
respectively, but currently this does not work if the target
frequency does not change along with the policy limit.

Namely, if the target frequency does not change along with the
policy min or max, the "target_freq == policy->cur" check in
__cpufreq_driver_target() prevents driver callbacks from being
invoked and they do not even have a chance to update the
corresponding internal boundary.

This particularly affects the "powersave" and "performance"
governors that always set the target frequency to one of the
policy limits and it never changes when the other limit is updated.

To allow cpufreq the drivers needing to update internal frequency
boundaries on policy limits changes to avoid this issue, introduce
a new driver flag, CPUFREQ_NEED_UPDATE_LIMITS, that (when set) will
neutralize the check mentioned above.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>

Without the explicit __always_inline, some RISC-V configs place the
functions out of line, triggering the BUILD_BUG_ON checks in the
function.

Fixes: 11129e8e ("riscv: use memcpy based uaccess for nommu again")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

A kernel-doc markup should start with the identifier on its
first line.
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/5b76c5625709aaaa3abee98faa620b9f3d27ff85.1603791716.git.mchehab+huawei@kernel.org

Right now, kernel-doc generates a warning:
	./include/drm/drm_dp_helper.h:1786: warning: Function parameter or member 'hbr2_reset' not described in 'drm_dp_phy_test_params'

This is due to a typo:

	@hb2_reset -> @hbr2_reset
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/2a615cb38e951215bb1bddc2481ad323c9cf3fc9.1603791716.git.mchehab+huawei@kernel.org

It is not possible to create cross-references for duplicated
symbols. While Sphinx always detected it, on Sphinx 3 it
generates warnings like this:

	.../Documentation/gpu/drm-kms-helpers:326: ../drivers/gpu/drm/drm_edid.c:1626: WARNING: Duplicate C declaration, also defined in 'gpu/drm-kms-helpers'.
	Declaration is 'bool drm_edid_are_equal (const struct edid *edid1, const struct edid *edid2)'.

So, get rid of the duplicated kernel-doc markup.
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/9310f4074fa9d29cd3ad60684d86d0ace8dab7ae.1603791716.git.mchehab+huawei@kernel.org

When a mlx5 core devlink instance is reloaded in different net namespace,
its associated IB device is deleted and recreated.

Example sequence is:
$ ip netns add foo
$ devlink dev reload pci/0000:00:08.0 netns foo
$ ip netns del foo

mlx5 IB device needs to attach and detach the netdevice to it through the
netdev notifier chain during load and unload sequence.  A below call graph
of the unload flow.

cleanup_net()
   down_read(&pernet_ops_rwsem); <- first sem acquired
     ops_pre_exit_list()
       pre_exit()
         devlink_pernet_pre_exit()
           devlink_reload()
             mlx5_devlink_reload_down()
               mlx5_unload_one()
               [...]
                 mlx5_ib_remove()
                   mlx5_ib_unbind_slave_port()
                     mlx5_remove_netdev_notifier()
                       unregister_netdevice_notifier()
                         down_write(&pernet_ops_rwsem);<- recurrsive lock

Hence, when net namespace is deleted, mlx5 reload results in deadlock.

When deadlock occurs, devlink mutex is also held. This not only deadlocks
the mlx5 device under reload, but all the processes which attempt to
access unrelated devlink devices are deadlocked.

Hence, fix this by mlx5 ib driver to register for per net netdev notifier
instead of global one, which operats on the net namespace without holding
the pernet_ops_rwsem.

Fixes: 4383cfcc ("net/mlx5: Add devlink reload")
Link: https://lore.kernel.org/r/20201026134359.23150-1-parav@nvidia.comSigned-off-by: NParav Pandit <parav@nvidia.com>
Signed-off-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>

UBSAN reports:

Undefined behaviour in ./include/linux/time64.h:127:27
signed integer overflow:
17179869187 * 1000000000 cannot be represented in type 'long long int'
Call Trace:
 timespec64_to_ns include/linux/time64.h:127 [inline]
 set_cpu_itimer+0x65c/0x880 kernel/time/itimer.c:180
 do_setitimer+0x8e/0x740 kernel/time/itimer.c:245
 __x64_sys_setitimer+0x14c/0x2c0 kernel/time/itimer.c:336
 do_syscall_64+0xa1/0x540 arch/x86/entry/common.c:295

Commit bd40a175 ("y2038: itimer: change implementation to timespec64")
replaced the original conversion which handled time clamping correctly with
timespec64_to_ns() which has no overflow protection.

Fix it in timespec64_to_ns() as this is not necessarily limited to the
usage in itimers.

[ tglx: Added comment and adjusted the fixes tag ]

Fixes: 361a3bf0 ("time64: Add time64.h header and define struct timespec64")
Signed-off-by: NZeng Tao <prime.zeng@hisilicon.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1598952616-6416-1-git-send-email-prime.zeng@hisilicon.com

Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.plSigned-off-by: NJoe Perches <joe@perches.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: NMiguel Ojeda <ojeda@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 453431a5 ("mm, treewide: rename kzfree() to
kfree_sensitive()") renamed kzfree() to kfree_sensitive(),
but it left a compatibility definition of kzfree() to avoid
being too disruptive.

Since then a few more instances of kzfree() have slipped in.

Just get rid of them and remove the compatibility definition
once and for all.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With the removal of the interrupt perturbations in previous random32
change (random32: make prandom_u32() output unpredictable), the PRNG
has become 100% deterministic again. While SipHash is expected to be
way more robust against brute force than the previous Tausworthe LFSR,
there's still the risk that whoever has even one temporary access to
the PRNG's internal state is able to predict all subsequent draws till
the next reseed (roughly every minute). This may happen through a side
channel attack or any data leak.

This patch restores the spirit of commit f227e3ec ("random32: update
the net random state on interrupt and activity") in that it will perturb
the internal PRNG's statee using externally collected noise, except that
it will not pick that noise from the random pool's bits nor upon
interrupt, but will rather combine a few elements along the Tx path
that are collectively hard to predict, such as dev, skb and txq
pointers, packet length and jiffies values. These ones are combined
using a single round of SipHash into a single long variable that is
mixed with the net_rand_state upon each invocation.

The operation was inlined because it produces very small and efficient
code, typically 3 xor, 2 add and 2 rol. The performance was measured
to be the same (even very slightly better) than before the switch to
SipHash; on a 6-core 12-thread Core i7-8700k equipped with a 40G NIC
(i40e), the connection rate dropped from 556k/s to 555k/s while the
SYN cookie rate grew from 5.38 Mpps to 5.45 Mpps.

Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
Cc: George Spelvin <lkml@sdf.org>
Cc: Amit Klein <aksecurity@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: NWilly Tarreau <w@1wt.eu>

Non-cryptographic PRNGs may have great statistical properties, but
are usually trivially predictable to someone who knows the algorithm,
given a small sample of their output.  An LFSR like prandom_u32() is
particularly simple, even if the sample is widely scattered bits.

It turns out the network stack uses prandom_u32() for some things like
random port numbers which it would prefer are *not* trivially predictable.
Predictability led to a practical DNS spoofing attack.  Oops.

This patch replaces the LFSR with a homebrew cryptographic PRNG based
on the SipHash round function, which is in turn seeded with 128 bits
of strong random key.  (The authors of SipHash have *not* been consulted
about this abuse of their algorithm.)  Speed is prioritized over security;
attacks are rare, while performance is always wanted.

Replacing all callers of prandom_u32() is the quick fix.
Whether to reinstate a weaker PRNG for uses which can tolerate it
is an open question.

Commit f227e3ec ("random32: update the net random state on interrupt
and activity") was an earlier attempt at a solution.  This patch replaces
it.
Reported-by: NAmit Klein <aksecurity@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Fixes: f227e3ec ("random32: update the net random state on interrupt and activity")
Signed-off-by: NGeorge Spelvin <lkml@sdf.org>
Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
[ willy: partial reversal of f227e3ec; moved SIPROUND definitions
  to prandom.h for later use; merged George's prandom_seed() proposal;
  inlined siprand_u32(); replaced the net_rand_state[] array with 4
  members to fix a build issue; cosmetic cleanups to make checkpatch
  happy; fixed RANDOM32_SELFTEST build ]
Signed-off-by: NWilly Tarreau <w@1wt.eu>

This patch introduces a new ioctl for vhost-vdpa device that can
report the iova range by the device.

For device that implements get_iova_range() method, we fetch it from
the vDPA device. If device doesn't implement get_iova_range() but
depends on platform IOMMU, we will query via DOMAIN_ATTR_GEOMETRY,
otherwise [0, ULLONG_MAX] is assumed.

For safety, this patch also rules out the map request which is not in
the valid range.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20201023090043.14430-3-jasowang@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

This patch introduce a config op to get valid iova range from the vDPA
device.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20201023090043.14430-2-jasowang@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>

With the switch to the lateeoi model for interdomain event channels
some functions are no longer in use. Remove them.
Suggested-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NJan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20201022094907.28560-2-jgross@suse.comSigned-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

Dirty logging is a key feature of the KVM MMU and must be supported by
the TDP MMU. Add support for both the write protection and PML dirty
logging modes.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: NBen Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-16-bgardon@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When starting a HP machine with HIL driver but without an HIL keyboard
or HIL mouse attached, it may happen that data written to the HIL loop
gets stuck (e.g. because the transaction queue is full).  Usually one
will then have to reboot the machine because all you see is and endless
output of:
 Transaction add failed: transaction already queued?

In the higher layers hp_sdc_enqueue_transaction() is called to queued up
a HIL packet. This function returns an error code, and this patch adds
the necessary checks for this return code and disables the HIL driver if
further packets can't be sent.

Tested on a HP 730 and a HP 715/64 machine.
Signed-off-by: NHelge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>

With the set_fs change, we can no longer rely on copy_{to,from}_user()
accepting a kernel pointer, and it was bad form to do so anyway. Clean
this up and change the internal helper that io_uring uses to deal with
kernel pointers instead. This puts the offset copy in/out in __do_splice()
instead, which just calls the same helper.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch adds fast commit recovery path support for Ext4 file
system. We add several helper functions that are similar in spirit to
e2fsprogs journal recovery path handlers. Example of such functions
include - a simple block allocator, idempotent block bitmap update
function etc. Using these routines and the fast commit log in the fast
commit area, the recovery path (ext4_fc_replay()) performs fast commit
log recovery.
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-8-harshadshirwadkar@gmail.comSigned-off-by: NTheodore Ts'o <tytso@mit.edu>

This patch adds fast commit recovery support in JBD2.
Signed-off-by: NHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-7-harshadshirwadkar@gmail.comSigned-off-by: NTheodore Ts'o <tytso@mit.edu>

This patch adds main fast commit commit path handlers. The overall
patch can be divided into two inter-related parts:

(A) Metadata updates tracking

    This part consists of helper functions to track changes that need
    to be committed during a commit operation. These updates are
    maintained by Ext4 in different in-memory queues. Following are
    the APIs and their short description that are implemented in this
    patch:

    - ext4_fc_track_link/unlink/creat() - Track unlink. link and creat
      operations
    - ext4_fc_track_range() - Track changed logical block offsets
      inodes
    - ext4_fc_track_inode() - Track inodes
    - ext4_fc_mark_ineligible() - Mark file system fast commit
      ineligible()
    - ext4_fc_start_update() / ext4_fc_stop_update() /
      ext4_fc_start_ineligible() / ext4_fc_stop_ineligible() These
      functions are useful for co-ordinating inode updates with
      commits.

(B) Main commit Path

    This part consists of functions to convert updates tracked in
    in-memory data structures into on-disk commits. Function
    ext4_fc_commit() is the main entry point to commit path.
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-6-harshadshirwadkar@gmail.comSigned-off-by: NTheodore Ts'o <tytso@mit.edu>