Pull RCU updates from Ingo Molnar:
"The main RCU changes in this cycle were:
- Updates to use cond_resched() instead of cond_resched_rcu_qs()
where feasible (currently everywhere except in kernel/rcu and in
kernel/torture.c). Also a couple of fixes to avoid sending IPIs to
offline CPUs.
- Updates to simplify RCU's dyntick-idle handling.
- Updates to remove almost all uses of smp_read_barrier_depends() and
read_barrier_depends().
- Torture-test updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
torture: Save a line in stutter_wait(): while -> for
torture: Eliminate torture_runnable and perf_runnable
torture: Make stutter less vulnerable to compilers and races
locking/locktorture: Fix num reader/writer corner cases
locking/locktorture: Fix rwsem reader_delay
torture: Place all torture-test modules in one MAINTAINERS group
rcutorture/kvm-build.sh: Skip build directory check
rcutorture: Simplify functions.sh include path
rcutorture: Simplify logging
rcutorture/kvm-recheck-*: Improve result directory readability check
rcutorture/kvm.sh: Support execution from any directory
rcutorture/kvm.sh: Use consistent help text for --qemu-args
rcutorture/kvm.sh: Remove unused variable, `alldone`
rcutorture: Remove unused script, config2frag.sh
rcutorture/configinit: Fix build directory error message
rcutorture: Preempt RCU-preempt readers more vigorously
torture: Reduce #ifdefs for preempt_schedule()
rcu: Remove have_rcu_nocb_mask from tree_plugin.h
rcu: Add comment giving debug strategy for double call_rcu()
tracing, rcu: Hide trace event rcu_nocb_wake when not used
...
Pull x86/pti updates from Thomas Gleixner:
"Another set of melted spectrum related changes:
- Code simplifications and cleanups for RSB and retpolines.
- Make the indirect calls in KVM speculation safe.
- Whitelist CPUs which are known not to speculate from Meltdown and
prepare for the new CPUID flag which tells the kernel that a CPU is
not affected.
- A less rigorous variant of the module retpoline check which merily
warns when a non-retpoline protected module is loaded and reflects
that fact in the sysfs file.
- Prepare for Indirect Branch Prediction Barrier support.
- Prepare for exposure of the Speculation Control MSRs to guests, so
guest OSes which depend on those "features" can use them. Includes
a blacklist of the broken microcodes. The actual exposure of the
MSRs through KVM is still being worked on"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Simplify indirect_branch_prediction_barrier()
x86/retpoline: Simplify vmexit_fill_RSB()
x86/cpufeatures: Clean up Spectre v2 related CPUID flags
x86/cpu/bugs: Make retpoline module warning conditional
x86/bugs: Drop one "mitigation" from dmesg
x86/nospec: Fix header guards names
x86/alternative: Print unadorned pointers
x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
x86/msr: Add definitions for new speculation control MSRs
x86/cpufeatures: Add AMD feature bits for Speculation Control
x86/cpufeatures: Add Intel feature bits for Speculation Control
x86/cpufeatures: Add CPUID_7_EDX CPUID leaf
module/retpoline: Warn about missing retpoline in module
KVM: VMX: Make indirect call speculation safe
KVM: x86: Make indirect calls in emulator speculation safe
There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.
To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.
If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.
[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Since kernel 4.9, the thread_info has been moved into task_struct, no
longer locates at the bottom of kernel stack.
See commits c65eacbe29 ("sched/core: Allow putting thread_info into
task_struct") and 15f4eae70d ("x86: Move thread_info into
task_struct").
Before fix:
(gdb) set $current = $lx_current()
(gdb) p $lx_thread_info($current)
$1 = {flags = 1470918301}
(gdb) p $current.thread_info
$2 = {flags = 2147483648}
After fix:
(gdb) p $lx_thread_info($current)
$1 = {flags = 2147483648}
(gdb) p $current.thread_info
$2 = {flags = 2147483648}
Link: http://lkml.kernel.org/r/20180118210159.17223-1-imxikangjie@gmail.com
Fixes: 15f4eae70d ("x86: Move thread_info into task_struct")
Signed-off-by: Xi Kangjie <imxikangjie@gmail.com>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Kieran Bingham <kbingham@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are a couple of problems with the decodecode script and arm64:
1. AArch64 objdump refuses to disassemble .4byte directives as instructions,
insisting that they are data values and displaying them as:
a94153f3 .word 0xa94153f3 <-- trapping instruction
This is resolved by using the .inst directive instead.
2. Disassembly of branch instructions attempts to provide the target as
an offset from a symbol, e.g.:
0: 34000082 cbz w2, 10 <.text+0x10>
however this falls foul of the grep -v, which matches lines containing
".text" and ends up removing all branch instructions from the dump.
This patch resolves both issues by using the .inst directive for 4-byte
quantities on arm64 and stripping the resulting binaries (as is done on
arm already) to remove the mapping symbols.
Link: http://lkml.kernel.org/r/1506596147-23630-1-git-send-email-will.deacon@arm.com
Signed-off-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 pti bits and fixes from Thomas Gleixner:
"This last update contains:
- An objtool fix to prevent a segfault with the gold linker by
changing the invocation order. That's not just for gold, it's a
general robustness improvement.
- An improved error message for objtool which spares tearing hairs.
- Make KASAN fail loudly if there is not enough memory instead of
oopsing at some random place later
- RSB fill on context switch to prevent RSB underflow and speculation
through other units.
- Make the retpoline/RSB functionality work reliably for both Intel
and AMD
- Add retpoline to the module version magic so mismatch can be
detected
- A small (non-fix) update for cpufeatures which prevents cpu feature
clashing for the upcoming extra mitigation bits to ease
backporting"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
module: Add retpoline tag to VERMAGIC
x86/cpufeature: Move processor tracing out of scattered features
objtool: Improve error message for bad file argument
objtool: Fix seg fault with gold linker
x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros
x86/retpoline: Fill RSB on context switch for affected CPUs
x86/kasan: Panic if there is not enough memory to boot
Objtool segfaults when the gold linker is used with
CONFIG_MODVERSIONS=y and CONFIG_UNWINDER_ORC=y.
With CONFIG_MODVERSIONS=y, the .o file gets passed to the linker before
being passed to objtool. The gold linker seems to strip unused ELF
symbols by default, which confuses objtool and causes the seg fault when
it's trying to generate ORC metadata.
Objtool should really be running immediately after GCC anyway, without a
linker call in between. Change the makefile ordering so that objtool is
called before the linker.
Reported-and-tested-by: Markus <M4rkusXXL@web.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: ee9f8fce99 ("x86/unwind: Add the ORC unwinder")
Link: http://lkml.kernel.org/r/355f04da33581f4a3bf82e5b512973624a1e23a2.1516025651.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull Kbuild fixes from Masahiro Yamada:
- fix cross-compilation for architectures that setup CROSS_COMPILE in
their arch Makefile
- fix Kconfig rational operators for bool / tristate
- drop a gperf-generated file from .gitignore
* tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
genksyms: drop *.hash.c from .gitignore
kconfig: fix relational operators for bool and tristate symbols
kbuild: move cc-option and cc-disable-warning after incl. arch Makefile
This is a left-over of commit bb3290d916 ("Remove gperf usage from
toolchain").
We do not generate a hash function any more.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit 31847b67be ("kconfig: allow use of relations other than
(in)equality") it is possible to use relational operators in Kconfig
statements. However, those operators give unexpected results when
applied to bool/tristate values:
(n < y) = y (correct)
(m < y) = y (correct)
(n < m) = n (wrong)
This happens because relational operators process bool and tristate
symbols as strings and m sorts before n. It makes little sense to do a
lexicographical compare on bool and tristate values though.
Documentation/kbuild/kconfig-language.txt states that expression can have
a value of 'n', 'm' or 'y' (or 0, 1, 2 respectively for calculations).
Let's make it so for relational comparisons with bool/tristate
expressions as well and document them. If at least one symbol is an
actual string then the lexicographical compare works just as before.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull RCU updates from Paul E. McKenney:
- Updates to use cond_resched() instead of cond_resched_rcu_qs()
where feasible (currently everywhere except in kernel/rcu and
in kernel/torture.c). Also a couple of fixes to avoid sending
IPIs to offline CPUs.
- Updates to simplify RCU's dyntick-idle handling.
- Updates to remove almost all uses of smp_read_barrier_depends()
and read_barrier_depends().
- Miscellaneous fixes.
- Torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull locking fixes from Ingo Molnar:
"Misc fixes:
- Fix a S390 boot hang that was caused by the lock-break logic.
Remove lock-break to begin with, as review suggested it was
unreasonably fragile and our confidence in its continued good
health is lower than our confidence in its removal.
- Remove the lockdep cross-release checking code for now, because of
unresolved false positive warnings. This should make lockdep work
well everywhere again.
- Get rid of the final (and single) ACCESS_ONCE() straggler and
remove the API from v4.15.
- Fix a liblockdep build warning"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/lib/lockdep: Add missing declaration of 'pr_cont()'
checkpatch: Remove ACCESS_ONCE() warning
compiler.h: Remove ACCESS_ONCE()
tools/include: Remove ACCESS_ONCE()
tools/perf: Convert ACCESS_ONCE() to READ_ONCE()
locking/lockdep: Remove the cross-release locking checks
locking/core: Remove break_lock field when CONFIG_GENERIC_LOCKBREAK=y
locking/core: Fix deadlock during boot on systems with GENERIC_LOCKBREAK
Now that both smp_read_barrier_depends() and read_barrier_depends()
are being de-emphasized, warn if any are added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
[ paulmck: Skipped checking files and handled whitespace per Joe Perches. ]
Pull documentation fixes from Jonathan Corbet:
"A handful of documentation fixes.
The most significant of these addresses a problem with the new warning
mode: it can break the build when confronted with a source file
containing malformed kerneldoc comments"
* tag 'docs-4.15-fixes' of git://git.lwn.net/linux:
Documentation: fix docs build error after source file removed
scsi: documentation: Fix case of 'scsi_device' struct mention(s)
genericirq.rst: Remove :c:func:`...` in code blocks
dmaengine: doc : Fix warning "Title underline too short" while make xmldocs
scripts/kernel-doc: Don't fail with status != 0 if error encountered with -none
My bisect scripts starting running into build failures when trying to
compile 4.15-rc1 with the builds failing with things like:
drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c:2078: error: Cannot parse struct or union!
The line in question is actually just a #define, but after some digging
it turns out that my scripts pass W=1 and since commit 3a025e1d1c
("Add optional check for bad kernel-doc comments") that results in
kernel-doc running on each source file. The file in question has a
badly formatted comment immediately before the #define:
/**
* struct brcmf_skbuff_cb reserves first two bytes in sk_buff::cb for
* bus layer usage.
*/
which causes the regex in dump_struct to fail (lack of braces following
struct declaration) and kernel-doc returns 1, which causes the build
to fail.
Fix the issue by always returning 0 from kernel-doc when invoked with
-none. It successfully generates no documentation, and prints out any
issues.
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Mergr misc fixes from Andrew Morton:
"28 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (28 commits)
fs/hugetlbfs/inode.c: change put_page/unlock_page order in hugetlbfs_fallocate()
mm/hugetlb: fix NULL-pointer dereference on 5-level paging machine
autofs: revert "autofs: fix AT_NO_AUTOMOUNT not being honored"
autofs: revert "autofs: take more care to not update last_used on path walk"
fs/fat/inode.c: fix sb_rdonly() change
mm, memcg: fix mem_cgroup_swapout() for THPs
mm: migrate: fix an incorrect call of prep_transhuge_page()
kmemleak: add scheduling point to kmemleak_scan()
scripts/bloat-o-meter: don't fail with division by 0
fs/mbcache.c: make count_objects() more robust
Revert "mm/page-writeback.c: print a warning if the vm dirtiness settings are illogical"
mm/madvise.c: fix madvise() infinite loop under special circumstances
exec: avoid RLIMIT_STACK races with prlimit()
IB/core: disable memory registration of filesystem-dax vmas
v4l2: disable filesystem-dax mapping support
mm: fail get_vaddr_frames() for filesystem-dax mappings
mm: introduce get_user_pages_longterm
device-dax: implement ->split() to catch invalid munmap attempts
mm, hugetlbfs: introduce ->split() to vm_operations_struct
scripts/faddr2line: extend usage on generic arch
...
printk specifier %p now hashes all addresses before printing. Sometimes
we need to see the actual unmodified address. This can be achieved using
%lx but then we face the risk that if in future we want to change the
way the Kernel handles printing of pointers we will have to grep through
the already existent 50 000 %lx call sites. Let's add specifier %px as a
clear, opt-in, way to print a pointer and maintain some level of
isolation from all the other hex integer output within the Kernel.
Add printk specifier %px to print the actual unmodified address.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Pull timer updates from Thomas Gleixner:
- The final conversion of timer wheel timers to timer_setup().
A few manual conversions and a large coccinelle assisted sweep and
the removal of the old initialization mechanisms and the related
code.
- Remove the now unused VSYSCALL update code
- Fix permissions of /proc/timer_list. I still need to get rid of that
file completely
- Rename a misnomed clocksource function and remove a stale declaration
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
m68k/macboing: Fix missed timer callback assignment
treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
timer: Remove redundant __setup_timer*() macros
timer: Pass function down to initialization routines
timer: Remove unused data arguments from macros
timer: Switch callback prototype to take struct timer_list * argument
timer: Pass timer_list pointer to callbacks unconditionally
Coccinelle: Remove setup_timer.cocci
timer: Remove setup_*timer() interface
timer: Remove init_timer() interface
treewide: setup_timer() -> timer_setup() (2 field)
treewide: setup_timer() -> timer_setup()
treewide: init_timer() -> setup_timer()
treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
s390: cmm: Convert timers to use timer_setup()
lightnvm: Convert timers to use timer_setup()
drivers/net: cris: Convert timers to use timer_setup()
drm/vc4: Convert timers to use timer_setup()
block/laptop_mode: Convert timers to use timer_setup()
net/atm/mpc: Avoid open-coded assignment of timer callback function
...
Pull more Kbuild updates from Masahiro Yamada:
- use 'pwd' instead of '/bin/pwd' for portability
- clean up Makefiles
- fix ld-option for clang
- fix malloc'ed data size in Kconfig
- fix parallel building along with coccicheck
- fix a minor issue of package building
- prompt to use "rpm-pkg" instead of "rpm"
- clean up *.i and *.lst patterns by "make clean"
* tag 'kbuild-v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: drop $(extra-y) from real-objs-y
kbuild: clean up *.i and *.lst patterns by make clean
kbuild: rpm: prompt to use "rpm-pkg" if "rpm" target is used
kbuild: pkg: use --transform option to prefix paths in tar
coccinelle: fix parallel build with CHECK=scripts/coccicheck
kconfig/symbol.c: use correct pointer type argument for sizeof
kbuild: Set KBUILD_CFLAGS before incl. arch Makefile
kbuild: remove all dummy assignments to obj-
kbuild: create built-in.o automatically if parent directory wants it
kbuild: /bin/pwd -> pwd
Pull documentation updates from Jonathan Corbet:
"A few late-arriving docs updates that have no real reason to wait.
There's a new "Co-Developed-by" tag described by Greg, and a build
enhancement from Willy to generate docs warnings during a kernel build
(but only when additional warnings have been requested in general)"
* tag 'docs-4.15-2' of git://git.lwn.net/linux:
Add optional check for bad kernel-doc comments
Documentation: fix profile= options in kernel-parameters.txt
documentation/svga.txt: update outdated file
kokr/memory-barriers.txt: Fix typo in paring example
kokr/memory-barriers/txt: Replace uses of "transitive"
Documentation/process: add Co-Developed-by: tag for patches with multiple authors
