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git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- fix build rules in binderfs sample
- fix build errors when Kbuild recurses to the top Makefile
- covert '---help---' in Kconfig to 'help'
* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
treewide: replace '---help---' in Kconfig files with 'help'
kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
samples: binderfs: really compile this sample and fix build issues
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Pull more SCSI updates from James Bottomley:
"This is the set of changes collected since just before the merge
window opened. It's mostly minor fixes in drivers.
The one non-driver set is the three optical disk (sr) changes where
two are error path fixes and one is a helper conversion.
The big driver change is the hpsa compat_alloc_userspace rework by Al
so he can kill the remaining user. This has been tested and acked by
the maintainer"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
scsi: acornscsi: Fix an error handling path in acornscsi_probe()
scsi: storvsc: Remove memset before memory freeing in storvsc_suspend()
scsi: cxlflash: Remove an unnecessary NULL check
scsi: ibmvscsi: Don't send host info in adapter info MAD after LPM
scsi: sr: Fix sr_probe() missing deallocate of device minor
scsi: sr: Fix sr_probe() missing mutex_destroy
scsi: st: Convert convert get_user_pages() --> pin_user_pages()
scsi: target: Rename target_setup_cmd_from_cdb() to target_cmd_parse_cdb()
scsi: target: Fix NULL pointer dereference
scsi: target: Initialize LUN in transport_init_se_cmd()
scsi: target: Factor out a new helper, target_cmd_init_cdb()
scsi: hpsa: hpsa_ioctl(): Tidy up a bit
scsi: hpsa: Get rid of compat_alloc_user_space()
scsi: hpsa: Don't bother with vmalloc for BIG_IOCTL_Command_struct
scsi: hpsa: Lift {BIG_,}IOCTL_Command_struct copy{in,out} into hpsa_ioctl()
scsi: ufs: Remove redundant urgent_bkop_lvl initialization
scsi: ufs: Don't update urgent bkops level when toggling auto bkops
scsi: qedf: Remove redundant initialization of variable rc
scsi: mpt3sas: Fix memset() in non-RDPQ mode
scsi: iscsi: Fix reference count leak in iscsi_boot_create_kobj
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git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
"I2C has quite some patches for you this time. I hope it is the move to
per-driver-maintainers which is now showing results. We will see.
The big news is two new drivers (Nuvoton NPCM and Qualcomm CCI),
larger refactoring of the Designware, Tegra, and PXA drivers, the
Cadence driver supports being a slave now, and there is support to
instanciate SPD eeproms for well-known cases (which will be
user-visible because the i801 driver supports it), and some
devm_platform_ioremap_resource() conversions which blow up the
diffstat.
Note that I applied the Nuvoton driver quite late, so some minor fixup
patches arrived during the merge window. I chose to apply them right
away because they were trivial"
* 'i2c/for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (109 commits)
i2c: Drop stray comma in MODULE_AUTHOR statements
i2c: npcm7xx: npcm_i2caddr[] can be static
MAINTAINERS: npcm7xx: Add maintainer for Nuvoton NPCM BMC
i2c: npcm7xx: Fix a couple of error codes in probe
i2c: icy: Fix build with CONFIG_AMIGA_PCMCIA=n
i2c: npcm7xx: Remove unnecessary parentheses
i2c: npcm7xx: Add support for slave mode for Nuvoton
i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver
dt-bindings: i2c: npcm7xx: add NPCM I2C controller
i2c: pxa: don't error out if there's no pinctrl
i2c: add 'single-master' property to generic bindings
i2c: designware: Add Baikal-T1 System I2C support
i2c: designware: Move reg-space remapping into a dedicated function
i2c: designware: Retrieve quirk flags as early as possible
i2c: designware: Convert driver to using regmap API
i2c: designware: Discard Cherry Trail model flag
i2c: designware: Add Baytrail sem config DW I2C platform dependency
i2c: designware: slave: Set DW I2C core module dependency
i2c: designware: Use `-y` to build multi-object modules
dt-bindings: i2c: dw: Add Baikal-T1 SoC I2C controller
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git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull more media updates from Mauro Carvalho Chehab:
- a set of atomisp patches. They remove several abstraction layers, and
fixes clang and gcc warnings (that were hidden via some macros that
were disabling 4 or 5 types of warnings there). There are also some
important fixes and sensor auto-detection on newer BIOSes via ACPI
_DCM tables.
- some fixes
* tag 'media/v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (95 commits)
media: rkvdec: Fix H264 scaling list order
media: v4l2-ctrls: Unset correct HEVC loop filter flag
media: videobuf2-dma-contig: fix bad kfree in vb2_dma_contig_clear_max_seg_size
media: v4l2-subdev.rst: correct information about v4l2 events
media: s5p-mfc: Properly handle dma_parms for the allocated devices
media: medium: cec: Make MEDIA_CEC_SUPPORT default to n if !MEDIA_SUPPORT
media: cedrus: Implement runtime PM
media: cedrus: Program output format during each run
media: atomisp: improve ACPI/DMI detection logs
media: Revert "media: atomisp: add Asus Transform T101HA ACPI vars"
media: Revert "media: atomisp: Add some ACPI detection info"
media: atomisp: improve sensor detection code to use _DSM table
media: atomisp: get rid of an iomem abstraction layer
media: atomisp: get rid of a string_support.h abstraction layer
media: atomisp: use strscpy() instead of less secure variants
media: atomisp: set DFS to MAX if sensor doesn't report fps
media: atomisp: use different dfs failed messages
media: atomisp: change the detection of ISP2401 at runtime
media: atomisp: use macros from intel-family.h
media: atomisp: don't set hpll_freq twice with different values
...
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git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"Small collection of cleanups to rework usage of ->queuedata and the
GUID api"
* tag 'libnvdimm-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
nvdimm/pmem: stop using ->queuedata
nvdimm/btt: stop using ->queuedata
nvdimm/blk: stop using ->queuedata
libnvdimm: Replace guid_copy() with import_guid() where it makes sense
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Let's keep "git status" happy and quiet.
Fixes: f5b5a164f9a1 ("Add sample notification program")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Pull iomap fix from Darrick Wong:
"A single iomap bug fix for a variable type mistake on 32-bit
architectures, fixing an integer overflow problem in the unshare
actor"
* tag 'iomap-5.8-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: Fix unsharing of an extent >2GB on a 32-bit machine
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Pull xfs fix from Darrick Wong:
"We've settled down into the bugfix phase; this one fixes a resource
leak on an error bailout path"
* tag 'xfs-5.8-merge-9' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: Add the missed xfs_perag_put() for xfs_ifree_cluster()
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Pull 9p update from Dominique Martinet:
"Another very quiet cycle... Only one commit: increase the size of the
ring used for xen transport"
* tag '9p-for-5.8' of git://github.com/martinetd/linux:
9p/xen: increase XEN_9PFS_RING_ORDER
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
"One fix for a recent change which broke nested KVM guests on Power9.
Thanks to Alexey Kardashevskiy"
* tag 'powerpc-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
KVM: PPC: Fix nested guest RC bits update
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Pull ARM fixes from Russell King:
- fix for "hex" Kconfig default to use 0x0 rather than 0 to allow these
to be removed from defconfigs
- fix from Ard Biesheuvel for EFI HYP mode booting
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8985/1: efi/decompressor: deal with HYP mode boot gracefully
ARM: 8984/1: Kconfig: set default ZBOOT_ROM_TEXT/BSS value to 0x0
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Pull OpenRISC update from Stafford Horne:
"One patch found wile I was getting the glibc port ready: fix issue
with clone TLS arg getting overwritten"
* tag 'for-linus' of git://github.com/openrisc/linux:
openrisc: Fix issue with argument clobbering for clone/fork
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git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha
Pull alpha updates from Matt Turner:
"A few changes for alpha. They're mostly small janitorial fixes but
there's also a build fix and most notably a patch from Mikulas that
fixes a hang on boot on the Avanti platform, which required quite a
bit of work and review"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha:
alpha: Fix build around srm_sysrq_reboot_op
alpha: c_next should increase position index
alpha: Replace sg++ with sg = sg_next(sg)
alpha: fix memory barriers so that they conform to the specification
alpha: remove unneeded semicolon in sys_eiger.c
alpha: remove unneeded semicolon in osf_sys.c
alpha: Replace strncmp with str_has_prefix
alpha: fix rtc port ranges
alpha: Kconfig: pedantic formatting
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RAS updates from Thomas Gleixner:
"RAS updates from Borislav Petkov:
- Unmap a whole guest page if an MCE is encountered in it to avoid
follow-on MCEs leading to the guest crashing, by Tony Luck.
This change collided with the entry changes and the merge
resolution would have been rather unpleasant. To avoid that the
entry branch was merged in before applying this. The resulting code
did not change over the rebase.
- AMD MCE error thresholding machinery cleanup and hotplug
sanitization, by Thomas Gleixner.
- Change the MCE notifiers to denote whether they have handled the
error and not break the chain early by returning NOTIFY_STOP, thus
giving the opportunity for the later handlers in the chain to see
it. By Tony Luck.
- Add AMD family 0x17, models 0x60-6f support, by Alexander Monakov.
- Last but not least, the usual round of fixes and improvements"
* tag 'ras-core-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
x86/mce/dev-mcelog: Fix -Wstringop-truncation warning about strncpy()
x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned
EDAC/amd64: Add AMD family 17h model 60h PCI IDs
hwmon: (k10temp) Add AMD family 17h model 60h PCI match
x86/amd_nb: Add AMD family 17h model 60h PCI IDs
x86/mcelog: Add compat_ioctl for 32-bit mcelog support
x86/mce: Drop bogus comment about mce.kflags
x86/mce: Fixup exception only for the correct MCEs
EDAC: Drop the EDAC report status checks
x86/mce: Add mce=print_all option
x86/mce: Change default MCE logger to check mce->kflags
x86/mce: Fix all mce notifiers to update the mce->kflags bitmask
x86/mce: Add a struct mce.kflags field
x86/mce: Convert the CEC to use the MCE notifier
x86/mce: Rename "first" function as "early"
x86/mce/amd, edac: Remove report_gart_errors
x86/mce/amd: Make threshold bank setting hotplug robust
x86/mce/amd: Cleanup threshold device remove path
x86/mce/amd: Straighten CPU hotplug path
x86/mce/amd: Sanitize thresholding device creation hotplug path
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 entry updates from Thomas Gleixner:
"The x86 entry, exception and interrupt code rework
This all started about 6 month ago with the attempt to move the Posix
CPU timer heavy lifting out of the timer interrupt code and just have
lockless quick checks in that code path. Trivial 5 patches.
This unearthed an inconsistency in the KVM handling of task work and
the review requested to move all of this into generic code so other
architectures can share.
Valid request and solved with another 25 patches but those unearthed
inconsistencies vs. RCU and instrumentation.
Digging into this made it obvious that there are quite some
inconsistencies vs. instrumentation in general. The int3 text poke
handling in particular was completely unprotected and with the batched
update of trace events even more likely to expose to endless int3
recursion.
In parallel the RCU implications of instrumenting fragile entry code
came up in several discussions.
The conclusion of the x86 maintainer team was to go all the way and
make the protection against any form of instrumentation of fragile and
dangerous code pathes enforcable and verifiable by tooling.
A first batch of preparatory work hit mainline with commit
d5f744f9a2ac ("Pull x86 entry code updates from Thomas Gleixner")
That (almost) full solution introduced a new code section
'.noinstr.text' into which all code which needs to be protected from
instrumentation of all sorts goes into. Any call into instrumentable
code out of this section has to be annotated. objtool has support to
validate this.
Kprobes now excludes this section fully which also prevents BPF from
fiddling with it and all 'noinstr' annotated functions also keep
ftrace off. The section, kprobes and objtool changes are already
merged.
The major changes coming with this are:
- Preparatory cleanups
- Annotating of relevant functions to move them into the
noinstr.text section or enforcing inlining by marking them
__always_inline so the compiler cannot misplace or instrument
them.
- Splitting and simplifying the idtentry macro maze so that it is
now clearly separated into simple exception entries and the more
interesting ones which use interrupt stacks and have the paranoid
handling vs. CR3 and GS.
- Move quite some of the low level ASM functionality into C code:
- enter_from and exit to user space handling. The ASM code now
calls into C after doing the really necessary ASM handling and
the return path goes back out without bells and whistels in
ASM.
- exception entry/exit got the equivivalent treatment
- move all IRQ tracepoints from ASM to C so they can be placed as
appropriate which is especially important for the int3
recursion issue.
- Consolidate the declaration and definition of entry points between
32 and 64 bit. They share a common header and macros now.
- Remove the extra device interrupt entry maze and just use the
regular exception entry code.
- All ASM entry points except NMI are now generated from the shared
header file and the corresponding macros in the 32 and 64 bit
entry ASM.
- The C code entry points are consolidated as well with the help of
DEFINE_IDTENTRY*() macros. This allows to ensure at one central
point that all corresponding entry points share the same
semantics. The actual function body for most entry points is in an
instrumentable and sane state.
There are special macros for the more sensitive entry points, e.g.
INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
They allow to put the whole entry instrumentation and RCU handling
into safe places instead of the previous pray that it is correct
approach.
- The INT3 text poke handling is now completely isolated and the
recursion issue banned. Aside of the entry rework this required
other isolation work, e.g. the ability to force inline bsearch.
- Prevent #DB on fragile entry code, entry relevant memory and
disable it on NMI, #MC entry, which allowed to get rid of the
nested #DB IST stack shifting hackery.
- A few other cleanups and enhancements which have been made
possible through this and already merged changes, e.g.
consolidating and further restricting the IDT code so the IDT
table becomes RO after init which removes yet another popular
attack vector
- About 680 lines of ASM maze are gone.
There are a few open issues:
- An escape out of the noinstr section in the MCE handler which needs
some more thought but under the aspect that MCE is a complete
trainwreck by design and the propability to survive it is low, this
was not high on the priority list.
- Paravirtualization
When PV is enabled then objtool complains about a bunch of indirect
calls out of the noinstr section. There are a few straight forward
ways to fix this, but the other issues vs. general correctness were
more pressing than parawitz.
- KVM
KVM is inconsistent as well. Patches have been posted, but they
have not yet been commented on or picked up by the KVM folks.
- IDLE
Pretty much the same problems can be found in the low level idle
code especially the parts where RCU stopped watching. This was
beyond the scope of the more obvious and exposable problems and is
on the todo list.
The lesson learned from this brain melting exercise to morph the
evolved code base into something which can be validated and understood
is that once again the violation of the most important engineering
principle "correctness first" has caused quite a few people to spend
valuable time on problems which could have been avoided in the first
place. The "features first" tinkering mindset really has to stop.
With that I want to say thanks to everyone involved in contributing to
this effort. Special thanks go to the following people (alphabetical
order): Alexandre Chartre, Andy Lutomirski, Borislav Petkov, Brian
Gerst, Frederic Weisbecker, Josh Poimboeuf, Juergen Gross, Lai
Jiangshan, Macro Elver, Paolo Bonzin,i Paul McKenney, Peter Zijlstra,
Vitaly Kuznetsov, and Will Deacon"
* tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (142 commits)
x86/entry: Force rcu_irq_enter() when in idle task
x86/entry: Make NMI use IDTENTRY_RAW
x86/entry: Treat BUG/WARN as NMI-like entries
x86/entry: Unbreak __irqentry_text_start/end magic
x86/entry: __always_inline CR2 for noinstr
lockdep: __always_inline more for noinstr
x86/entry: Re-order #DB handler to avoid *SAN instrumentation
x86/entry: __always_inline arch_atomic_* for noinstr
x86/entry: __always_inline irqflags for noinstr
x86/entry: __always_inline debugreg for noinstr
x86/idt: Consolidate idt functionality
x86/idt: Cleanup trap_init()
x86/idt: Use proper constants for table size
x86/idt: Add comments about early #PF handling
x86/idt: Mark init only functions __init
x86/entry: Rename trace_hardirqs_off_prepare()
x86/entry: Clarify irq_{enter,exit}_rcu()
x86/entry: Remove DBn stacks
x86/entry: Remove debug IDT frobbing
x86/entry: Optimize local_db_save() for virt
...
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Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull notification queue from David Howells:
"This adds a general notification queue concept and adds an event
source for keys/keyrings, such as linking and unlinking keys and
changing their attributes.
Thanks to Debarshi Ray, we do have a pull request to use this to fix a
problem with gnome-online-accounts - as mentioned last time:
https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47
Without this, g-o-a has to constantly poll a keyring-based kerberos
cache to find out if kinit has changed anything.
[ There are other notification pending: mount/sb fsinfo notifications
for libmount that Karel Zak and Ian Kent have been working on, and
Christian Brauner would like to use them in lxc, but let's see how
this one works first ]
LSM hooks are included:
- A set of hooks are provided that allow an LSM to rule on whether or
not a watch may be set. Each of these hooks takes a different
"watched object" parameter, so they're not really shareable. The
LSM should use current's credentials. [Wanted by SELinux & Smack]
- A hook is provided to allow an LSM to rule on whether or not a
particular message may be posted to a particular queue. This is
given the credentials from the event generator (which may be the
system) and the watch setter. [Wanted by Smack]
I've provided SELinux and Smack with implementations of some of these
hooks.
WHY
===
Key/keyring notifications are desirable because if you have your
kerberos tickets in a file/directory, your Gnome desktop will monitor
that using something like fanotify and tell you if your credentials
cache changes.
However, we also have the ability to cache your kerberos tickets in
the session, user or persistent keyring so that it isn't left around
on disk across a reboot or logout. Keyrings, however, cannot currently
be monitored asynchronously, so the desktop has to poll for it - not
so good on a laptop. This facility will allow the desktop to avoid the
need to poll.
DESIGN DECISIONS
================
- The notification queue is built on top of a standard pipe. Messages
are effectively spliced in. The pipe is opened with a special flag:
pipe2(fds, O_NOTIFICATION_PIPE);
The special flag has the same value as O_EXCL (which doesn't seem
like it will ever be applicable in this context)[?]. It is given up
front to make it a lot easier to prohibit splice&co from accessing
the pipe.
[?] Should this be done some other way? I'd rather not use up a new
O_* flag if I can avoid it - should I add a pipe3() system call
instead?
The pipe is then configured::
ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth);
ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter);
Messages are then read out of the pipe using read().
- It should be possible to allow write() to insert data into the
notification pipes too, but this is currently disabled as the
kernel has to be able to insert messages into the pipe *without*
holding pipe->mutex and the code to make this work needs careful
auditing.
- sendfile(), splice() and vmsplice() are disabled on notification
pipes because of the pipe->mutex issue and also because they
sometimes want to revert what they just did - but one or more
notification messages might've been interleaved in the ring.
- The kernel inserts messages with the wait queue spinlock held. This
means that pipe_read() and pipe_write() have to take the spinlock
to update the queue pointers.
- Records in the buffer are binary, typed and have a length so that
they can be of varying size.
This allows multiple heterogeneous sources to share a common
buffer; there are 16 million types available, of which I've used
just a few, so there is scope for others to be used. Tags may be
specified when a watchpoint is created to help distinguish the
sources.
- Records are filterable as types have up to 256 subtypes that can be
individually filtered. Other filtration is also available.
- Notification pipes don't interfere with each other; each may be
bound to a different set of watches. Any particular notification
will be copied to all the queues that are currently watching for it
- and only those that are watching for it.
- When recording a notification, the kernel will not sleep, but will
rather mark a queue as having lost a message if there's
insufficient space. read() will fabricate a loss notification
message at an appropriate point later.
- The notification pipe is created and then watchpoints are attached
to it, using one of:
keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);
watch_mount(AT_FDCWD, "/", 0, fd, 0x02);
watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03);
where in both cases, fd indicates the queue and the number after is
a tag between 0 and 255.
- Watches are removed if either the notification pipe is destroyed or
the watched object is destroyed. In the latter case, a message will
be generated indicating the enforced watch removal.
Things I want to avoid:
- Introducing features that make the core VFS dependent on the
network stack or networking namespaces (ie. usage of netlink).
- Dumping all this stuff into dmesg and having a daemon that sits
there parsing the output and distributing it as this then puts the
responsibility for security into userspace and makes handling
namespaces tricky. Further, dmesg might not exist or might be
inaccessible inside a container.
- Letting users see events they shouldn't be able to see.
TESTING AND MANPAGES
====================
- The keyutils tree has a pipe-watch branch that has keyctl commands
for making use of notifications. Proposed manual pages can also be
found on this branch, though a couple of them really need to go to
the main manpages repository instead.
If the kernel supports the watching of keys, then running "make
test" on that branch will cause the testing infrastructure to spawn
a monitoring process on the side that monitors a notifications pipe
for all the key/keyring changes induced by the tests and they'll
all be checked off to make sure they happened.
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch
- A test program is provided (samples/watch_queue/watch_test) that
can be used to monitor for keyrings, mount and superblock events.
Information on the notifications is simply logged to stdout"
* tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
smack: Implement the watch_key and post_notification hooks
selinux: Implement the watch_key security hook
keys: Make the KEY_NEED_* perms an enum rather than a mask
pipe: Add notification lossage handling
pipe: Allow buffers to be marked read-whole-or-error for notifications
Add sample notification program
watch_queue: Add a key/keyring notification facility
security: Add hooks to rule on setting a watch
pipe: Add general notification queue support
pipe: Add O_NOTIFICATION_PIPE
security: Add a hook for the point of notification insertion
uapi: General notification queue definitions
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EFI on ARM only supports short descriptors, and given that it mandates
that the MMU and caches are on, it is implied that booting in HYP mode
is not supported.
However, implementations of EFI exist (i.e., U-Boot) that ignore this
requirement, which is not entirely unreasonable, given that it makes
HYP mode inaccessible to the operating system.
So let's make sure that we can deal with this condition gracefully.
We already tolerate booting the EFI stub with the caches off (even
though this violates the EFI spec as well), and so we should deal
with HYP mode boot with MMU and caches either on or off.
- When the MMU and caches are on, we can ignore the HYP stub altogether,
since we can carry on executing at HYP. We do need to ensure that we
disable the MMU at HYP before entering the kernel proper.
- When the MMU and caches are off, we have to drop to SVC mode so that
we can set up the page tables using short descriptors. In this case,
we need to install the HYP stub as usual, so that we can return to HYP
mode before handing over to the kernel proper.
Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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ZBOOT_ROM_TEXT and ZBOOT_ROM_BSS are defined as 'hex' but had a default
of "0". Kconfig will helpfully expand a text entry of 0 to 0x0 but
because this is not the same as the default value it was treated as
being explicitly set when running 'make savedefconfig' so most arm
defconfigs have CONFIG_ZBOOT_ROM_TEXT=0x0 and CONFIG_ZBOOT_ROM_BSS=0x0.
Change the default to 0x0 which will mean next time the defconfigs are
re-generated the spurious config entries will be removed.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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The patch introducing the struct was probably never compile tested,
because it sets a handler with a wrong function signature. Wrap the
handler into a functions with the correct signature to fix the build.
Fixes: 0f1c9688a194 ("tty/sysrq: alpha: export and use __sysrq_get_key_op()")
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Matt Turner <mattst88@gmail.com>
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Signed-off-by: Matt Turner <mattst88@gmail.com>
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Replace sg++ with sg = sg_next(sg).
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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The commits cd0e00c10672 and 92d7223a7423 broke boot on the Alpha Avanti
platform. The patches move memory barriers after a write before the write.
The result is that if there's iowrite followed by ioread, there is no
barrier between them.
The Alpha architecture allows reordering of the accesses to the I/O space,
and the missing barrier between write and read causes hang with serial
port and real time clock.
This patch makes barriers confiorm to the specification.
1. We add mb() before readX_relaxed and writeX_relaxed -
memory-barriers.txt claims that these functions must be ordered w.r.t.
each other. Alpha doesn't order them, so we need an explicit barrier.
2. We add mb() before reads from the I/O space - so that if there's a
write followed by a read, there should be a barrier between them.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: cd0e00c10672 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering")
Fixes: 92d7223a7423 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering #2")
Cc: stable@vger.kernel.org # v4.17+
Acked-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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Fix the following coccicheck warning:
arch/alpha/kernel/sys_eiger.c:179:2-3: Unneeded semicolon
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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Fix the following coccicheck warning:
arch/alpha/kernel/osf_sys.c:680:2-3: Unneeded semicolon
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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In commit b6b2735514bc
("tracing: Use str_has_prefix() instead of using fixed sizes")
the newly introduced str_has_prefix() was used
to replace error-prone strncmp(str, const, len).
Here fix codes with the same pattern.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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Alpha incorrectly reports "0070-0080 : rtc" in /proc/ioports.
Fix this, so that it is "0070-007f".
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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Formatting of Kconfig files doesn't look so pretty, so let the
Great White Handkerchief come around and clean it up.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Signed-off-by: Matt Turner <mattst88@gmail.com>
|
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git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux
Pull thermal updates from Daniel Lezcano:
- Add the hwmon support on the i.MX SC (Anson Huang)
- Thermal framework cleanups (self-encapsulation, pointless stubs,
private structures) (Daniel Lezcano)
- Use the PM QoS frequency changes for the devfreq cooling device
(Matthias Kaehlcke)
- Remove duplicate error messages from platform_get_irq() error
handling (Markus Elfring)
- Add support for the bandgap sensors (Keerthy)
- Statically initialize .get_mode/.set_mode ops (Andrzej Pietrasiewicz)
- Add Renesas R-Car maintainer entry (Niklas Söderlund)
- Fix error checking after calling ti_bandgap_get_sensor_data() for the
TI SoC thermal (Sudip Mukherjee)
- Add latency constraint for the idle injection, the DT binding and the
change the registering function (Daniel Lezcano)
- Convert the thermal framework binding to the Yaml schema (Amit
Kucheria)
- Replace zero-length array with flexible-array on i.MX 8MM (Gustavo A.
R. Silva)
- Thermal framework cleanups (alphabetic order for heads, replace
module.h by export.h, make file naming consistent) (Amit Kucheria)
- Merge tsens-common into the tsens driver (Amit Kucheria)
- Fix platform dependency for the Qoriq driver (Geert Uytterhoeven)
- Clean up the rcar_thermal_update_temp() function in the rcar thermal
driver (Niklas Söderlund)
- Fix the TMSAR register for the TMUv2 on the Qoriq platform (Yuantian
Tang)
- Export GDDV, OEM vendor variables, and don't require IDSP for the
int340x thermal driver - trivial conflicts fixed (Matthew Garrett)
* tag 'thermal-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (48 commits)
thermal/int340x_thermal: Don't require IDSP to exist
thermal/int340x_thermal: Export OEM vendor variables
thermal/int340x_thermal: Export GDDV
thermal: qoriq: Update the settings for TMUv2
thermal: rcar_thermal: Clean up rcar_thermal_update_temp()
thermal: qoriq: Add platform dependencies
drivers: thermal: tsens: Merge tsens-common.c into tsens.c
thermal/of: Rename of-thermal.c
thermal/governors: Prefix all source files with gov_
thermal/drivers/user_space: Sort headers alphabetically
thermal/drivers/of-thermal: Sort headers alphabetically
thermal/drivers/cpufreq_cooling: Replace module.h with export.h
thermal/drivers/cpufreq_cooling: Sort headers alphabetically
thermal/drivers/clock_cooling: Include export.h
thermal/drivers/clock_cooling: Sort headers alphabetically
thermal/drivers/thermal_hwmon: Include export.h
thermal/drivers/thermal_hwmon: Sort headers alphabetically
thermal/drivers/thermal_helpers: Include export.h
thermal/drivers/thermal_helpers: Sort headers alphabetically
thermal/core: Replace module.h with export.h
...
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git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull proc fix from Eric Biederman:
"Much to my surprise syzbot found a very old bug in proc that the
recent changes made easier to reproce. This bug is subtle enough it
looks like it fooled everyone who should know better"
* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
proc: Use new_inode not new_inode_pseudo
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The idea of conditionally calling into rcu_irq_enter() only when RCU is
not watching turned out to be not completely thought through.
Paul noticed occasional premature end of grace periods in RCU torture
testing. Bisection led to the commit which made the invocation of
rcu_irq_enter() conditional on !rcu_is_watching().
It turned out that this conditional breaks RCU assumptions about the idle
task when the scheduler tick happens to be a nested interrupt. Nested
interrupts can happen when the first interrupt invokes softirq processing
on return which enables interrupts.
If that nested tick interrupt does not invoke rcu_irq_enter() then the
RCU's irq-nesting checks will believe that this interrupt came directly
from idle, which will cause RCU to report a quiescent state. Because this
interrupt instead came from a softirq handler which might have been
executing an RCU read-side critical section, this can cause the grace
period to end prematurely.
Change the condition from !rcu_is_watching() to is_idle_task(current) which
enforces that interrupts in the idle task unconditionally invoke
rcu_irq_enter() independent of the RCU state.
This is also correct vs. user mode entries in NOHZ full scenarios because
user mode entries bring RCU out of EQS and force the RCU irq nesting state
accounting to nested. As only the first interrupt can enter from user mode
a nested tick interrupt will enter from kernel mode and as the nesting
state accounting is forced to nesting it will not do anything stupid even
if rcu_irq_enter() has not been invoked.
Fixes: 3eeec3858488 ("x86/entry: Provide idtentry_entry/exit_cond_rcu()")
Reported-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: "Paul E. McKenney" <paulmck@kernel.org>
Reviewed-by: "Paul E. McKenney" <paulmck@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/87wo4cxubv.fsf@nanos.tec.linutronix.de
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git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
"Nothing too exciting for this cycle. A couple of fixes across the
board, and Lee volunteered to help with patch review"
* tag 'pwm/for-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
pwm: Add missing "CONFIG_" prefix
MAINTAINERS: Add Lee Jones as reviewer for the PWM subsystem
pwm: imx27: Fix rounding behavior
pwm: rockchip: Simplify rockchip_pwm_get_state()
pwm: img: Call pm_runtime_put() in pm_runtime_get_sync() failed case
pwm: tegra: Support dynamic clock frequency configuration
pwm: jz4740: Add support for the JZ4725B
pwm: jz4740: Make PWM start with the active part
pwm: jz4740: Enhance precision in calculation of duty cycle
pwm: jz4740: Drop dependency on MACH_INGENIC
pwm: lpss: Fix get_state runtime-pm reference handling
pwm: sun4i: Support direct clock output on Allwinner A64
pwm: Add support for Azoteq IQS620A PWM generator
dt-bindings: pwm: rcar: add r8a77961 support
pwm: Add missing '\n' in log messages
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git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu driver directory structure cleanup from Joerg Roedel:
"Move the Intel and AMD IOMMU drivers into their own subdirectory.
Both drivers consist of several files by now and giving them their own
directory unclutters the IOMMU top-level directory a bit"
* tag 'iommu-drivers-move-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/vt-d: Move Intel IOMMU driver into subdirectory
iommu/amd: Move AMD IOMMU driver into subdirectory
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git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk fix from Petr Mladek:
"One more printk change for 5.8: make sure that messages printed from
KDB context are redirected to KDB console handlers. It did not work
when KDB interrupted NMI or printk_safe contexts.
Arm people started hitting this problem more often recently. I forgot
to add the fix into the previous pull request by mistake"
* tag 'printk-for-5.8-kdb-nmi' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk/kdb: Redirect printk messages into kdb in any context
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Recently syzbot reported that unmounting proc when there is an ongoing
inotify watch on the root directory of proc could result in a use
after free when the watch is removed after the unmount of proc
when the watcher exits.
Commit 69879c01a0c3 ("proc: Remove the now unnecessary internal mount
of proc") made it easier to unmount proc and allowed syzbot to see the
problem, but looking at the code it has been around for a long time.
Looking at the code the fsnotify watch should have been removed by
fsnotify_sb_delete in generic_shutdown_super. Unfortunately the inode
was allocated with new_inode_pseudo instead of new_inode so the inode
was not on the sb->s_inodes list. Which prevented
fsnotify_unmount_inodes from finding the inode and removing the watch
as well as made it so the "VFS: Busy inodes after unmount" warning
could not find the inodes to warn about them.
Make all of the inodes in proc visible to generic_shutdown_super,
and fsnotify_sb_delete by using new_inode instead of new_inode_pseudo.
The only functional difference is that new_inode places the inodes
on the sb->s_inodes list.
I wrote a small test program and I can verify that without changes it
can trigger this issue, and by replacing new_inode_pseudo with
new_inode the issues goes away.
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/000000000000d788c905a7dfa3f4@google.com
Reported-by: syzbot+7d2debdcdb3cb93c1e5e@syzkaller.appspotmail.com
Fixes: 0097875bd415 ("proc: Implement /proc/thread-self to point at the directory of the current thread")
Fixes: 021ada7dff22 ("procfs: switch /proc/self away from proc_dir_entry")
Fixes: 51f0885e5415 ("vfs,proc: guarantee unique inodes in /proc")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity fix from Mimi Zohar:
"ima mprotect performance fix"
* tag 'integrity-v5.8-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: fix mprotect checking
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git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree fixes from Rob Herring:
- Another round of whack-a-mole removing 'allOf', redundant cases of
'maxItems' and incorrect 'reg' sizes
- Fix support for yaml.h in non-standard paths
* tag 'devicetree-fixes-for-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
dt-bindings: Remove redundant 'maxItems'
dt-bindings: Fix more incorrect 'reg' property sizes in examples
dt-bindings: phy: qcom: Fix missing 'ranges' and example addresses
dt-bindings: Remove more cases of 'allOf' containing a '$ref'
scripts/dtc: use pkg-config to include <yaml.h> in non-standard path
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git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2
Pull nios2 update from Ley Foon Tan:
"Mark expected switch fall-through in signal handling"
* tag 'nios2-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2:
nios2: signal: Mark expected switch fall-through
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Pull more KVM updates from Paolo Bonzini:
"The guest side of the asynchronous page fault work has been delayed to
5.9 in order to sync with Thomas's interrupt entry rework, but here's
the rest of the KVM updates for this merge window.
MIPS:
- Loongson port
PPC:
- Fixes
ARM:
- Fixes
x86:
- KVM_SET_USER_MEMORY_REGION optimizations
- Fixes
- Selftest fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (62 commits)
KVM: x86: do not pass poisoned hva to __kvm_set_memory_region
KVM: selftests: fix sync_with_host() in smm_test
KVM: async_pf: Inject 'page ready' event only if 'page not present' was previously injected
KVM: async_pf: Cleanup kvm_setup_async_pf()
kvm: i8254: remove redundant assignment to pointer s
KVM: x86: respect singlestep when emulating instruction
KVM: selftests: Don't probe KVM_CAP_HYPERV_ENLIGHTENED_VMCS when nested VMX is unsupported
KVM: selftests: do not substitute SVM/VMX check with KVM_CAP_NESTED_STATE check
KVM: nVMX: Consult only the "basic" exit reason when routing nested exit
KVM: arm64: Move hyp_symbol_addr() to kvm_asm.h
KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception
KVM: arm64: Make vcpu_cp1x() work on Big Endian hosts
KVM: arm64: Remove host_cpu_context member from vcpu structure
KVM: arm64: Stop sparse from moaning at __hyp_this_cpu_ptr
KVM: arm64: Handle PtrAuth traps early
KVM: x86: Unexport x86_fpu_cache and make it static
KVM: selftests: Ignore KVM 5-level paging support for VM_MODE_PXXV48_4K
KVM: arm64: Save the host's PtrAuth keys in non-preemptible context
KVM: arm64: Stop save/restoring ACTLR_EL1
KVM: arm64: Add emulation for 32bit guests accessing ACTLR2
...
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git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
- several smaller cleanups
- a fix for a Xen guest regression with CPU offlining
- a small fix in the xen pvcalls backend driver
- an update of MAINTAINERS
* tag 'for-linus-5.8b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
MAINTAINERS: Update PARAVIRT_OPS_INTERFACE and VMWARE_HYPERVISOR_INTERFACE
xen/pci: Get rid of verbose_request and use dev_dbg() instead
xenbus: Use dev_printk() when possible
xen-pciback: Use dev_printk() when possible
xen: enable BALLOON_MEMORY_HOTPLUG by default
xen: expand BALLOON_MEMORY_HOTPLUG description
xen/pvcalls: Make pvcalls_back_global static
xen/cpuhotplug: Fix initial CPU offlining for PV(H) guests
xen-platform: Constify dev_pm_ops
xen/pvcalls-back: test for errors when calling backend_connect()
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There's no need to specify 'maxItems' with the same value as the number
of entries in 'items'. A meta-schema update will catch future cases.
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Anson Huang <Anson.Huang@nxp.com>
Cc: linux-clk@vger.kernel.org
Cc: linux-pwm@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Reviewed-by: Stephen Boyd <sboyd@kernel.org> # clk
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
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Make sure IMA is enabled before checking mprotect change. Addresses
report of a 3.7% regression of boot-time.dhcp.
Fixes: 8eb613c0b8f1 ("ima: verify mprotect change is consistent with mmap policy")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Tested-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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For no reason other than beginning brainmelt, IDTENTRY_NMI was mapped to
IDTENTRY_IST.
This is not a problem on 64bit because the IST default entry point maps to
IDTENTRY_RAW which does not any entry handling. The surplus function
declaration for the noist C entry point is unused and as there is no ASM
code emitted for NMI this went unnoticed.
On 32bit IDTENTRY_IST maps to a regular IDTENTRY which does the normal
entry handling. That is clearly the wrong thing to do for NMI.
Map it to IDTENTRY_RAW to unbreak it. The IDTENTRY_NMI mapping needs to
stay to avoid emitting ASM code.
Fixes: 6271fef00b34 ("x86/entry: Convert NMI to IDTENTRY_NMI")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Debugged-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/CA+G9fYvF3cyrY+-iw_SZtpN-i2qA2BruHg4M=QYECU2-dNdsMw@mail.gmail.com
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BUG/WARN are cleverly optimized using UD2 to handle the BUG/WARN out of
line in an exception fixup.
But if BUG or WARN is issued in a funny RCU context, then the
idtentry_enter...() path might helpfully WARN that the RCU context is
invalid, which results in infinite recursion.
Split the BUG/WARN handling into an nmi_enter()/nmi_exit() path in
exc_invalid_op() to increase the chance to survive the experience.
[ tglx: Make the declaration match the implementation ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/f8fe40e0088749734b4435b554f73eee53dcf7a8.1591932307.git.luto@kernel.org
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Before commit 6cdf30375f82 ("powerpc/kvm/book3s: Use kvm helpers
to walk shadow or secondary table") we called __find_linux_pte() with
a page table pointer from a kvm_nested_guest struct but
now we rely on kvmhv_find_nested() which takes an L1 LPID and returns
a kvm_nested_guest pointer, however we pass a L0 LPID there and
the L2 guest hangs.
This fixes the LPID passed to kvmppc_hv_handle_set_rc().
Fixes: 6cdf30375f82 ("powerpc/kvm/book3s: Use kvm helpers to walk shadow or secondary table")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200611030559.75257-1-aik@ozlabs.ru
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Mark switch cases where we are expecting to fall through.
Fix the following warning through the use of the new the new
pseudo-keyword fallthrough;
arch/nios2/kernel/signal.c:254:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
254 | restart = -2;
| ~~~~~~~~^~~~
arch/nios2/kernel/signal.c:255:3: note: here
255 | case ERESTARTNOHAND:
| ^~~~
Reported-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull the Kernel Concurrency Sanitizer from Thomas Gleixner:
"The Kernel Concurrency Sanitizer (KCSAN) is a dynamic race detector,
which relies on compile-time instrumentation, and uses a
watchpoint-based sampling approach to detect races.
The feature was under development for quite some time and has already
found legitimate bugs.
Unfortunately it comes with a limitation, which was only understood
late in the development cycle:
It requires an up to date CLANG-11 compiler
CLANG-11 is not yet released (scheduled for June), but it's the only
compiler today which handles the kernel requirements and especially
the annotations of functions to exclude them from KCSAN
instrumentation correctly.
These annotations really need to work so that low level entry code and
especially int3 text poke handling can be completely isolated.
A detailed discussion of the requirements and compiler issues can be
found here:
https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/
We came to the conclusion that trying to work around compiler
limitations and bugs again would end up in a major trainwreck, so
requiring a working compiler seemed to be the best choice.
For Continous Integration purposes the compiler restriction is
manageable and that's where most xxSAN reports come from.
For a change this limitation might make GCC people actually look at
their bugs. Some issues with CSAN in GCC are 7 years old and one has
been 'fixed' 3 years ago with a half baken solution which 'solved' the
reported issue but not the underlying problem.
The KCSAN developers also ponder to use a GCC plugin to become
independent, but that's not something which will show up in a few
days.
Blocking KCSAN until wide spread compiler support is available is not
a really good alternative because the continuous growth of lockless
optimizations in the kernel demands proper tooling support"
* tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
compiler_types.h, kasan: Use __SANITIZE_ADDRESS__ instead of CONFIG_KASAN to decide inlining
compiler.h: Move function attributes to compiler_types.h
compiler.h: Avoid nested statement expression in data_race()
compiler.h: Remove data_race() and unnecessary checks from {READ,WRITE}_ONCE()
kcsan: Update Documentation to change supported compilers
kcsan: Remove 'noinline' from __no_kcsan_or_inline
kcsan: Pass option tsan-instrument-read-before-write to Clang
kcsan: Support distinguishing volatile accesses
kcsan: Restrict supported compilers
kcsan: Avoid inserting __tsan_func_entry/exit if possible
ubsan, kcsan: Don't combine sanitizer with kcov on clang
objtool, kcsan: Add kcsan_disable_current() and kcsan_enable_current_nowarn()
kcsan: Add __kcsan_{enable,disable}_current() variants
checkpatch: Warn about data_race() without comment
kcsan: Use GFP_ATOMIC under spin lock
Improve KCSAN documentation a bit
kcsan: Make reporting aware of KCSAN tests
kcsan: Fix function matching in report
kcsan: Change data_race() to no longer require marking racing accesses
kcsan: Move kcsan_{disable,enable}_current() to kcsan-checks.h
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull atomics rework from Thomas Gleixner:
"Peter Zijlstras rework of atomics and fallbacks. This solves two
problems:
1) Compilers uninline small atomic_* static inline functions which
can expose them to instrumentation.
2) The instrumentation of atomic primitives was done at the
architecture level while composites or fallbacks were provided at
the generic level. As a result there are no uninstrumented
variants of the fallbacks.
Both issues were in the way of fully isolating fragile entry code
pathes and especially the text poke int3 handler which is prone to an
endless recursion problem when anything in that code path is about to
be instrumented. This was always a problem, but got elevated due to
the new batch mode updates of tracing.
The solution is to mark the functions __always_inline and to flip the
fallback and instrumentation so the non-instrumented variants are at
the architecture level and the instrumentation is done in generic
code.
The latter introduces another fallback variant which will go away once
all architectures have been moved over to arch_atomic_*"
* tag 'locking-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomics: Flip fallbacks and instrumentation
asm-generic/atomic: Use __always_inline for fallback wrappers
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Pull updates from Andrew Morton:
"A few fixes and stragglers.
Subsystems affected by this patch series: mm/memory-failure, ocfs2,
lib/lzo, misc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
amdgpu: a NULL ->mm does not mean a thread is a kthread
lib/lzo: fix ambiguous encoding bug in lzo-rle
ocfs2: fix build failure when TCP/IP is disabled
mm/memory-failure: send SIGBUS(BUS_MCEERR_AR) only to current thread
mm/memory-failure: prioritize prctl(PR_MCE_KILL) over vm.memory_failure_early_kill
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