AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity
930,754 Commits 7 Branches 0 Tags 1.9 GiB
9cb8f069de
Commit Graph

33332 Commits

Author SHA1 Message Date
Dmitry Safonov
9cb8f069de kernel: rename show_stack_loglvl() => show_stack() 
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-09 09:39:13 -07:00
Dmitry Safonov
fe1993a001 kernel: use show_stack_loglvl() 
Align the last users of show_stack() by KERN_DEFAULT as the surrounding
headers/messages.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-50-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-09 09:39:13 -07:00
Dmitry Safonov
8ba09b1dc1 sched: print stack trace with KERN_INFO 
Aligning with other messages printed in sched_show_task() - use KERN_INFO
to print the backtrace.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-49-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-09 09:39:12 -07:00
Dmitry Safonov
77819daf24 kdb: don't play with console_loglevel 
Print the stack trace with KERN_EMERG - it should be always visible.

Playing with console_loglevel is a bad idea as there may be more messages
printed than wanted.  Also the stack trace might be not printed at all if
printk() was deferred and console_loglevel was raised back before the
trace got flushed.

Unfortunately, after rebasing on commit 2277b49258 ("kdb: Fix stack
crawling on 'running' CPUs that aren't the master"), kdb_show_stack() uses
now kdb_dump_stack_on_cpu(), which for now won't be converted as it uses
dump_stack() instead of show_stack().

Convert for now the branch that uses show_stack() and remove
console_loglevel exercise from that case.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-48-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-09 09:39:12 -07:00
Dmitry Safonov
2062a4e8ae kallsyms/printk: add loglvl to print_ip_sym() 
Patch series "Add log level to show_stack()", v3.

Add log level argument to show_stack().

Done in three stages:
1. Introducing show_stack_loglvl() for every architecture
2. Migrating old users with an explicit log level
3. Renaming show_stack_loglvl() into show_stack()

Justification:

- It's a design mistake to move a business-logic decision into platform
  realization detail.

- I have currently two patches sets that would benefit from this work:
  Removing console_loglevel jumps in sysrq driver [1] Hung task warning
  before panic [2] - suggested by Tetsuo (but he probably didn't realise
  what it would involve).

- While doing (1), (2) the backtraces were adjusted to headers and other
  messages for each situation - so there won't be a situation when the
  backtrace is printed, but the headers are missing because they have
  lesser log level (or the reverse).

- As the result in (2) plays with console_loglevel for kdb are removed.

The least important for upstream, but maybe still worth to note that every
company I've worked in so far had an off-list patch to print backtrace
with the needed log level (but only for the architecture they cared
about).  If you have other ideas how you will benefit from show_stack()
with a log level - please, reply to this cover letter.

See also discussion on v1:
https://lore.kernel.org/linux-riscv/20191106083538.z5nlpuf64cigxigh@pathway.suse.cz/

This patch (of 50):

print_ip_sym() needs to have a log level parameter to comply with other
parts being printed.  Otherwise, half of the expected backtrace would be
printed and other may be missing with some logging level.

The following callee(s) are using now the adjusted log level:
- microblaze/unwind: the same level as headers & userspace unwind.
  Note that pr_debug()'s there are for debugging the unwinder itself.
- nds32/traps: symbol addresses are printed with the same log level
  as backtrace headers.
- lockdep: ip for locking issues is printed with the same log level
  as other part of the warning.
- sched: ip where preemption was disabled is printed as error like
  the rest part of the message.
- ftrace: bug reports are now consistent in the log level being used.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Will Deacon <will@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-2-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-09 09:39:10 -07:00
Christoph Hellwig
490741ab1b module: move the set_fs hack for flush_icache_range to m68k 
flush_icache_range generally operates on kernel addresses, but for some
reason m68k needed a set_fs override.  Move that into the m68k code
insted of keeping it in the module loader.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: http://lkml.kernel.org/r/20200515143646.3857579-30-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:58 -07:00
Christoph Hellwig
885f7f8e30 mm: rename flush_icache_user_range to flush_icache_user_page 
The function currently known as flush_icache_user_range only operates on
a single page.  Rename it to flush_icache_user_page as we'll need the
name flush_icache_user_range for something else soon.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20200515143646.3857579-20-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:58 -07:00
Souptick Joarder
dadbb612f6 mm/gup.c: convert to use get_user_{page|pages}_fast_only() 
API __get_user_pages_fast() renamed to get_user_pages_fast_only() to
align with pin_user_pages_fast_only().

As part of this we will get rid of write parameter.  Instead caller will
pass FOLL_WRITE to get_user_pages_fast_only().  This will not change any
existing functionality of the API.

All the callers are changed to pass FOLL_WRITE.

Also introduce get_user_page_fast_only(), and use it in a few places
that hard-code nr_pages to 1.

Updated the documentation of the API.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>		[arch/powerpc/kvm]
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Michal Suchanek <msuchanek@suse.de>
Link: http://lkml.kernel.org/r/1590396812-31277-1-git-send-email-jrdr.linux@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Rafael Aquini
e77132e758 kernel/sysctl.c: ignore out-of-range taint bits introduced via kernel.tainted 
Users with SYS_ADMIN capability can add arbitrary taint flags to the
running kernel by writing to /proc/sys/kernel/tainted or issuing the
command 'sysctl -w kernel.tainted=...'.  This interface, however, is
open for any integer value and this might cause an invalid set of flags
being committed to the tainted_mask bitset.

This patch introduces a simple way for proc_taint() to ignore any
eventual invalid bit coming from the user input before committing those
bits to the kernel tainted_mask.

Signed-off-by: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Link: http://lkml.kernel.org/r/20200512223946.888020-1-aquini@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Guilherme G. Piccoli
60c958d8df panic: add sysctl to dump all CPUs backtraces on oops event 
Usually when the kernel reaches an oops condition, it's a point of no
return; in case not enough debug information is available in the kernel
splat, one of the last resorts would be to collect a kernel crash dump
and analyze it.  The problem with this approach is that in order to
collect the dump, a panic is required (to kexec-load the crash kernel).
When in an environment of multiple virtual machines, users may prefer to
try living with the oops, at least until being able to properly shutdown
their VMs / finish their important tasks.

This patch implements a way to collect a bit more debug details when an
oops event is reached, by printing all the CPUs backtraces through the
usage of NMIs (on architectures that support that).  The sysctl added
(and documented) here was called "oops_all_cpu_backtrace", and when set
will (as the name suggests) dump all CPUs backtraces.

Far from ideal, this may be the last option though for users that for
some reason cannot panic on oops.  Most of times oopses are clear enough
to indicate the kernel portion that must be investigated, but in virtual
environments it's possible to observe hypervisor/KVM issues that could
lead to oopses shown in other guests CPUs (like virtual APIC crashes).
This patch hence aims to help debug such complex issues without
resorting to kdump.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Link: http://lkml.kernel.org/r/20200327224116.21030-1-gpiccoli@canonical.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Guilherme G. Piccoli
0ec9dc9bcb kernel/hung_task.c: introduce sysctl to print all traces when a hung task is detected 
Commit 401c636a0e ("kernel/hung_task.c: show all hung tasks before
panic") introduced a change in that we started to show all CPUs
backtraces when a hung task is detected _and_ the sysctl/kernel
parameter "hung_task_panic" is set.  The idea is good, because usually
when observing deadlocks (that may lead to hung tasks), the culprit is
another task holding a lock and not necessarily the task detected as
hung.

The problem with this approach is that dumping backtraces is a slightly
expensive task, specially printing that on console (and specially in
many CPU machines, as servers commonly found nowadays).  So, users that
plan to collect a kdump to investigate the hung tasks and narrow down
the deadlock definitely don't need the CPUs backtrace on dmesg/console,
which will delay the panic and pollute the log (crash tool would easily
grab all CPUs traces with 'bt -a' command).

Also, there's the reciprocal scenario: some users may be interested in
seeing the CPUs backtraces but not have the system panic when a hung
task is detected.  The current approach hence is almost as embedding a
policy in the kernel, by forcing the CPUs backtraces' dump (only) on
hung_task_panic.

This patch decouples the panic event on hung task from the CPUs
backtraces dump, by creating (and documenting) a new sysctl called
"hung_task_all_cpu_backtrace", analog to the approach taken on soft/hard
lockups, that have both a panic and an "all_cpu_backtrace" sysctl to
allow individual control.  The new mechanism for dumping the CPUs
backtraces on hung task detection respects "hung_task_warnings" by not
dumping the traces in case there's no warnings left.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: http://lkml.kernel.org/r/20200327223646.20779-1-gpiccoli@canonical.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Guilherme G. Piccoli
f117955a22 kernel/watchdog.c: convert {soft/hard}lockup boot parameters to sysctl aliases 
After a recent change introduced by Vlastimil's series [0], kernel is
able now to handle sysctl parameters on kernel command line; also, the
series introduced a simple infrastructure to convert legacy boot
parameters (that duplicate sysctls) into sysctl aliases.

This patch converts the watchdog parameters softlockup_panic and
{hard,soft}lockup_all_cpu_backtrace to use the new alias infrastructure.
It fixes the documentation too, since the alias only accepts values 0 or
1, not the full range of integers.

We also took the opportunity here to improve the documentation of the
previously converted hung_task_panic (see the patch series [0]) and put
the alias table in alphabetical order.

[0] http://lkml.kernel.org/r/20200427180433.7029-1-vbabka@suse.cz

Signed-off-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Link: http://lkml.kernel.org/r/20200507214624.21911-1-gpiccoli@canonical.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Vlastimil Babka
b467f3ef3c kernel/hung_task convert hung_task_panic boot parameter to sysctl 
We can now handle sysctl parameters on kernel command line and have
infrastructure to convert legacy command line options that duplicate
sysctl to become a sysctl alias.

This patch converts the hung_task_panic parameter.  Note that the sysctl
handler is more strict and allows only 0 and 1, while the legacy
parameter allowed any non-zero value.  But there is little reason anyone
would not be using 1.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Guilherme G . Piccoli" <gpiccoli@canonical.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Ivan Teterevkov <ivan.teterevkov@nutanix.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200427180433.7029-4-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Rafael Aquini
db38d5c106 kernel: add panic_on_taint 
Analogously to the introduction of panic_on_warn, this patch introduces
a kernel option named panic_on_taint in order to provide a simple and
generic way to stop execution and catch a coredump when the kernel gets
tainted by any given flag.

This is useful for debugging sessions as it avoids having to rebuild the
kernel to explicitly add calls to panic() into the code sites that
introduce the taint flags of interest.

For instance, if one is interested in proceeding with a post-mortem
analysis at the point a given code path is hitting a bad page (i.e.
unaccount_page_cache_page(), or slab_bug()), a coredump can be collected
by rebooting the kernel with 'panic_on_taint=0x20' amended to the
command line.

Another, perhaps less frequent, use for this option would be as a means
for assuring a security policy case where only a subset of taints, or no
single taint (in paranoid mode), is allowed for the running system.  The
optional switch 'nousertaint' is handy in this particular scenario, as
it will avoid userspace induced crashes by writes to sysctl interface
/proc/sys/kernel/tainted causing false positive hits for such policies.

[akpm@linux-foundation.org: tweak kernel-parameters.txt wording]

Suggested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Bunk <bunk@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>
Link: http://lkml.kernel.org/r/20200515175502.146720-1-aquini@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-08 11:05:56 -07:00
Linus Torvalds
9aa900c809 Char/Misc driver patches for 5.8-rc1 
Here is the large set of char/misc driver patches for 5.8-rc1
 
 Included in here are:
 	- habanalabs driver updates, loads
 	- mhi bus driver updates
 	- extcon driver updates
 	- clk driver updates (approved by the clock maintainer)
 	- firmware driver updates
 	- fpga driver updates
 	- gnss driver updates
 	- coresight driver updates
 	- interconnect driver updates
 	- parport driver updates (it's still alive!)
 	- nvmem driver updates
 	- soundwire driver updates
 	- visorbus driver updates
 	- w1 driver updates
 	- various misc driver updates
 
 In short, loads of different driver subsystem updates along with the
 drivers as well.
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXtzkHw8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yldOwCgus/DgpnI1UL4z+NdBxJrAXtkPmgAn2sgTUea
 i5RblCmcVMqvHaGtYkY+
 =tScN
 -----END PGP SIGNATURE-----

Merge tag 'char-misc-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the large set of char/misc driver patches for 5.8-rc1

  Included in here are:

   - habanalabs driver updates, loads

   - mhi bus driver updates

   - extcon driver updates

   - clk driver updates (approved by the clock maintainer)

   - firmware driver updates

   - fpga driver updates

   - gnss driver updates

   - coresight driver updates

   - interconnect driver updates

   - parport driver updates (it's still alive!)

   - nvmem driver updates

   - soundwire driver updates

   - visorbus driver updates

   - w1 driver updates

   - various misc driver updates

  In short, loads of different driver subsystem updates along with the
  drivers as well.

  All have been in linux-next for a while with no reported issues"

* tag 'char-misc-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (233 commits)
  habanalabs: correctly cast u64 to void*
  habanalabs: initialize variable to default value
  extcon: arizona: Fix runtime PM imbalance on error
  extcon: max14577: Add proper dt-compatible strings
  extcon: adc-jack: Fix an error handling path in 'adc_jack_probe()'
  extcon: remove redundant assignment to variable idx
  w1: omap-hdq: print dev_err if irq flags are not cleared
  w1: omap-hdq: fix interrupt handling which did show spurious timeouts
  w1: omap-hdq: fix return value to be -1 if there is a timeout
  w1: omap-hdq: cleanup to add missing newline for some dev_dbg
  /dev/mem: Revoke mappings when a driver claims the region
  misc: xilinx-sdfec: convert get_user_pages() --> pin_user_pages()
  misc: xilinx-sdfec: cleanup return value in xsdfec_table_write()
  misc: xilinx-sdfec: improve get_user_pages_fast() error handling
  nvmem: qfprom: remove incorrect write support
  habanalabs: handle MMU cache invalidation timeout
  habanalabs: don't allow hard reset with open processes
  habanalabs: GAUDI does not support soft-reset
  habanalabs: add print for soft reset due to event
  habanalabs: improve MMU cache invalidation code
  ...
 2020-06-07 10:59:32 -07:00
Linus Torvalds
081096d98b TTY/Serial driver updates for 5.8-rc1 
Here is the tty and serial driver updates for 5.8-rc1
 
 Nothing huge at all, just a lot of little serial driver fixes, updates
 for new devices and features, and other small things.  Full details are
 in the shortlog.
 
 Note, you will get a conflict merging with your tree in the
 Documentation/devicetree/bindings/serial/rs485.yaml file, but it should
 be pretty obvious what to do.  If not, I'm sure Rob will clean it all up
 afterwards :)
 
 All of these have been in linux-next with no issues for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXtzpCg8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ylRxACgjGtOKPjahONL4lWd0F8ZYEcyw7sAn34woBCO
 BDUV3kolrRQ4OYNJWsHP
 =TvqG
 -----END PGP SIGNATURE-----

Merge tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the tty and serial driver updates for 5.8-rc1

  Nothing huge at all, just a lot of little serial driver fixes, updates
  for new devices and features, and other small things. Full details are
  in the shortlog.

  All of these have been in linux-next with no issues for a while"

* tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (67 commits)
  tty: serial: qcom_geni_serial: Add 51.2MHz frequency support
  tty: serial: imx: clear Ageing Timer Interrupt in handler
  serial: 8250_fintek: Add F81966 Support
  sc16is7xx: Add flag to activate IrDA mode
  dt-bindings: sc16is7xx: Add flag to activate IrDA mode
  serial: 8250: Support rs485 bus termination GPIO
  serial: 8520_port: Fix function param documentation
  dt-bindings: serial: Add binding for rs485 bus termination GPIO
  vt: keyboard: avoid signed integer overflow in k_ascii
  serial: 8250: Enable 16550A variants by default on non-x86
  tty: hvc_console, fix crashes on parallel open/close
  serial: imx: Initialize lock for non-registered console
  sc16is7xx: Read the LSR register for basic device presence check
  sc16is7xx: Allow sharing the IRQ line
  sc16is7xx: Use threaded IRQ
  sc16is7xx: Always use falling edge IRQ
  tty: n_gsm: Fix bogus i++ in gsm_data_kick
  tty: n_gsm: Remove unnecessary test in gsm_print_packet()
  serial: stm32: add no_console_suspend support
  tty: serial: fsl_lpuart: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
  ...
 2020-06-07 09:52:36 -07:00
Linus Torvalds
cff11abeca Kbuild updates for v5.8 
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
 
  - ensure to rebuild all objects when the compiler is upgraded
 
  - exclude system headers from dependency tracking and fixdep processing
 
  - fix potential bit-size mismatch between the kernel and BPF user-mode
    helper
 
  - add the new syntax 'userprogs' to build user-space programs for the
    target architecture (the same arch as the kernel)
 
  - compile user-space sample code under samples/ for the target arch
    instead of the host arch
 
  - make headers_install fail if a CONFIG option is leaked to user-space
 
  - sanitize the output format of scripts/checkstack.pl
 
  - handle ARM 'push' instruction in scripts/checkstack.pl
 
  - error out before modpost if a module name conflict is found
 
  - error out when multiple directories are passed to M= because this
    feature is broken for a long time
 
  - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
 
  - a lot of cleanups of modpost
 
  - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
    second pass of modpost
 
  - do not run the second pass of modpost if nothing in modules is updated
 
  - install modules.builtin(.modinfo) by 'make install' as well as by
    'make modules_install' because it is useful even when CONFIG_MODULES=n
 
  - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
    to allow users to use alternatives such as pigz, pbzip2, etc.
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl7brm0VHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGjeEP/Rrf8H9cp/Tq+ALQCBycI3W5ZEHg
 n2EqprZkVP2MlOV0d+8b9t4PdZf6E5Wmfv26sMaBAhl6X1KQI/0NgPMnTINvy5jJ
 Q2SMhj9y8Gwr3XKFu9Hd/0U+Sax5rz+LmY84tdF95dXzPIUWjAEVnbmN+ofY6T++
 sNf2YGNFSR6iiqr3uCYA0hHZmpKlfhVgDPAdncWa5aadSsuQb79nZQWefGeVEsuD
 HrISpwnkhBc0qY1xyWry6agE92xWmkNkdjKq6A7peguZL02XySWLRWjyHoiiaPOB
 6U4urKs/NSXqPgxGxwZthhwERHryC3+g4s8wRBDKE6ISRWKBBA2ruHpgdF5h/utu
 re1ZP2qRcAt8NBFynr4MEb2AU0mYkv7iEgfLJ7NUCRlMOtqrn5RFwnS4r8ReyQp5
 1UM11RbPhYgYjM5g9hBHJ7nK944/kfvy1/4jF4I1+M5O7QL6f00pu3r2bBIa/65g
 DWrNOpIliKG27GgnRlxi7HgLfxs9etFcXTpHO0ymgnMmlz+7FQsdceR9qqybGU9o
 yBWw6zculMQjb3E+k0DTnE5kLWsycbua921wxM9ABSxRmJi7WciNF73RdLUIBoAY
 VUbwrP2aIpdL+2uyX6RqdTaWzEBpW8omszr46aQ96pX+RiqMrPvJRLaA/tr3ZH8g
 tdHenJPWdHSaOcO4
 =GKe5
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

 - fix potential bit-size mismatch between the kernel and BPF user-mode
   helper

 - add the new syntax 'userprogs' to build user-space programs for the
   target architecture (the same arch as the kernel)

 - compile user-space sample code under samples/ for the target arch
   instead of the host arch

 - make headers_install fail if a CONFIG option is leaked to user-space

 - sanitize the output format of scripts/checkstack.pl

 - handle ARM 'push' instruction in scripts/checkstack.pl

 - error out before modpost if a module name conflict is found

 - error out when multiple directories are passed to M= because this
   feature is broken for a long time

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

 - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
   second pass of modpost

 - do not run the second pass of modpost if nothing in modules is
   updated

 - install modules.builtin(.modinfo) by 'make install' as well as by
   'make modules_install' because it is useful even when
   CONFIG_MODULES=n

 - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
   to allow users to use alternatives such as pigz, pbzip2, etc.

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info->size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod->skip struct member
  modpost: add mod->is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod->is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
 2020-06-06 12:00:25 -07:00
Linus Torvalds
1ee18de929 dma-mapping updates for 5.8, part 1 
- enhance the dma pool to allow atomic allocation on x86 with AMD SEV
    (David Rientjes)
  - two small cleanups (Jason Yan and Peter Collingbourne)
 -----BEGIN PGP SIGNATURE-----
 
 iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAl7bvTULHGhjaEBsc3Qu
 ZGUACgkQD55TZVIEUYMJVhAAgTiWNzxPJhM6RTeRooM6W0NvcZGTJT6ExyJghaau
 aJvHUjXPrRmeBM8Zjwbbu5dioncd8c7npfRjBvATaEL74pa1u9gH3jnUTxh6L4WQ
 /FTNYryZVbprXJsdFuDZvCsO/CChqfZL8PWz+NFgIpICOyyXdorQELMhCaeOhnfU
 /goq6SvKmPlmXdb4eM2fXRD7udt1qlp+Oq2EZUdT3Xb4CBFsWUYbOMde22VY390Z
 2E9mEztOaKjNgAM/TfCoXo7iRUSwxcpO5aSliDhJJ/7uWaxyWTzFlaoIlwIkkNKb
 TcguNJbIZtjIXwBMv9gS6CqVEgFymmWqX5Tr23+vbb7S/235HqKtN1dPmV2h4R0H
 QOpvYXfm6kc4tpH4J32NMp+IqfQmwgMbNtUsiXWk5Lxl27cb8K2Q5eqEwxRWMbG+
 HObO7Kzb8oCygWwozZ+3QcWSr+9QAgzsb4Jl4jg6adjd8LDcbmKo4B9TKptGpVnL
 xjDleKdb/P4Vq55q9KHFLjqFUesuQIv2mKl2s+zr2BqROxjZ562kM9QHwsoCqc4Q
 tFuVed+XOoT7yhdKdtwEK7lwcQBtZgP5l/HgsoosmuJ975holsQ4pbKSf4A2Y4yo
 XwHYonSwOAEbi4nPxnvKIm4aUNq+PC44TH0VJcXud3tmQ/DGipdlLW8/nyw9ecfa
 qaQ=
 =GT3J
 -----END PGP SIGNATURE-----

Merge tag 'dma-mapping-5.8' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - enhance the dma pool to allow atomic allocation on x86 with AMD SEV
   (David Rientjes)

 - two small cleanups (Jason Yan and Peter Collingbourne)

* tag 'dma-mapping-5.8' of git://git.infradead.org/users/hch/dma-mapping:
  dma-contiguous: fix comment for dma_release_from_contiguous
  dma-pool: scale the default DMA coherent pool size with memory capacity
  x86/mm: unencrypted non-blocking DMA allocations use coherent pools
  dma-pool: add pool sizes to debugfs
  dma-direct: atomic allocations must come from atomic coherent pools
  dma-pool: dynamically expanding atomic pools
  dma-pool: add additional coherent pools to map to gfp mask
  dma-remap: separate DMA atomic pools from direct remap code
  dma-debug: make __dma_entry_alloc_check_leak() static
 2020-06-06 11:43:23 -07:00
Linus Torvalds
fe3bc8a988 Merge branch 'for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 
Pull workqueue updates from Tejun Heo:
 "Mostly cleanups and other trivial changes.

  The only interesting change is Sebastian's rcuwait conversion for RT"

* 'for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: use BUILD_BUG_ON() for compile time test instead of WARN_ON()
  workqueue: fix a piece of comment about reserved bits for work flags
  workqueue: remove useless unlock() and lock() in series
  workqueue: void unneeded requeuing the pwq in rescuer thread
  workqueue: Convert the pool::lock and wq_mayday_lock to raw_spinlock_t
  workqueue: Use rcuwait for wq_manager_wait
  workqueue: Remove unnecessary kfree() call in rcu_free_wq()
  workqueue: Fix an use after free in init_rescuer()
  workqueue: Use IS_ERR and PTR_ERR instead of PTR_ERR_OR_ZERO.
 2020-06-06 10:01:48 -07:00
Linus Torvalds
4a7e89c5ec Merge branch 'for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 
Pull cgroup updates from Tejun Heo:
 "Just two patches: one to add system-level cpu.stat to the root cgroup
  for convenience and a trivial comment update"

* 'for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: add cpu.stat file to root cgroup
  cgroup: Remove stale comments
 2020-06-06 09:59:34 -07:00
Denis Efremov
8dfb61dcba kbuild: add variables for compression tools 
Allow user to use alternative implementations of compression tools,
such as pigz, pbzip2, pxz. For example, multi-threaded tools to
speed up the build:
$ make GZIP=pigz BZIP2=pbzip2

Variables _GZIP, _BZIP2, _LZOP are used internally because original env
vars are reserved by the tools. The use of GZIP in gzip tool is obsolete
since 2015. However, alternative implementations (e.g., pigz) still rely
on it. BZIP2, BZIP, LZOP vars are not obsolescent.

The credit goes to @grsecurity.

As a sidenote, for multi-threaded lzma, xz compression one can use:
$ export XZ_OPT="--threads=0"

Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
 2020-06-06 23:42:01 +09:00
Linus Torvalds
7ae77150d9 powerpc updates for 5.8 
- Support for userspace to send requests directly to the on-chip GZIP
    accelerator on Power9.
 
  - Rework of our lockless page table walking (__find_linux_pte()) to make it
    safe against parallel page table manipulations without relying on an IPI for
    serialisation.
 
  - A series of fixes & enhancements to make our machine check handling more
    robust.
 
  - Lots of plumbing to add support for "prefixed" (64-bit) instructions on
    Power10.
 
  - Support for using huge pages for the linear mapping on 8xx (32-bit).
 
  - Remove obsolete Xilinx PPC405/PPC440 support, and an associated sound driver.
 
  - Removal of some obsolete 40x platforms and associated cruft.
 
  - Initial support for booting on Power10.
 
  - Lots of other small features, cleanups & fixes.
 
 Thanks to:
   Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Andrey Abramov,
   Aneesh Kumar K.V, Balamuruhan S, Bharata B Rao, Bulent Abali, Cédric Le
   Goater, Chen Zhou, Christian Zigotzky, Christophe JAILLET, Christophe Leroy,
   Dmitry Torokhov, Emmanuel Nicolet, Erhard F., Gautham R. Shenoy, Geoff Levand,
   George Spelvin, Greg Kurz, Gustavo A. R. Silva, Gustavo Walbon, Haren Myneni,
   Hari Bathini, Joel Stanley, Jordan Niethe, Kajol Jain, Kees Cook, Leonardo
   Bras, Madhavan Srinivasan., Mahesh Salgaonkar, Markus Elfring, Michael
   Neuling, Michal Simek, Nathan Chancellor, Nathan Lynch, Naveen N. Rao,
   Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pingfan Liu, Qian Cai, Ram
   Pai, Raphael Moreira Zinsly, Ravi Bangoria, Sam Bobroff, Sandipan Das, Segher
   Boessenkool, Stephen Rothwell, Sukadev Bhattiprolu, Tyrel Datwyler, Wolfram
   Sang, Xiongfeng Wang.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCAAxFiEEJFGtCPCthwEv2Y/bUevqPMjhpYAFAl7aYZ8THG1wZUBlbGxl
 cm1hbi5pZC5hdQAKCRBR6+o8yOGlgPiKD/9zNCuZLFMAFrIdbm0HlYA2RGYZFT75
 GUHsqYyei1pxA7PgM3KwJiXELVODsBv0eQbgNh1tbecKrxPRegN/cywd1KLjPZ7I
 v5/qweQP8MvR0RhzjbhvUcO0jq/f8u2LbJr5mUfVzjU6tAvrvcWo3oZqDElsekCS
 kgyOH3r1vZ2PLTMiGFhb0gWi2iqc+6BHU1AFCGPCMjB1Vu5d5+54VvZ/6lllGsOF
 yg9CBXmmVvQ+Bn6tH4zdEB78FYxnAIwBqlbmL79i5ca+HQJ0Sw6HuPRy9XYq35p6
 2EiXS4Wrgp7i7+1TN3HO362u5Onb8TSyQU7NS6yCFPoJ6JQxcJMBIw6mHhnXOPuZ
 CrjgcdwUMjx8uDoKmX1Epbfuex2w+AysW+4yBHPFiSgl3klKC3D0wi95mR485w2F
 rN8uzJtrDeFKcYZJG7IoB/cgFCCPKGf9HaXr8q0S/jBKMffx91ul3cfzlfdIXOCw
 FDNw/+ZX7UD6ddFEG12ZTO+vdL8yf1uCRT/DIZwUiDMIA0+M6F4nc7j3lfyZfoO1
 65f9UlhoLxScq7VH2fKH4UtZatO9cPID2z1CmiY4UbUIPtFDepSuYClgLF+Duf4b
 rkfxhKU0+Ja1zNH5XNc+L+Bc5/W4lFiJXz02dYIjtHoUpWkc1aToOETVwzggYFNM
 G3PXIBOI0jRgRw==
 =o0WU
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Support for userspace to send requests directly to the on-chip GZIP
   accelerator on Power9.

 - Rework of our lockless page table walking (__find_linux_pte()) to
   make it safe against parallel page table manipulations without
   relying on an IPI for serialisation.

 - A series of fixes & enhancements to make our machine check handling
   more robust.

 - Lots of plumbing to add support for "prefixed" (64-bit) instructions
   on Power10.

 - Support for using huge pages for the linear mapping on 8xx (32-bit).

 - Remove obsolete Xilinx PPC405/PPC440 support, and an associated sound
   driver.

 - Removal of some obsolete 40x platforms and associated cruft.

 - Initial support for booting on Power10.

 - Lots of other small features, cleanups & fixes.

Thanks to: Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
Andrey Abramov, Aneesh Kumar K.V, Balamuruhan S, Bharata B Rao, Bulent
Abali, Cédric Le Goater, Chen Zhou, Christian Zigotzky, Christophe
JAILLET, Christophe Leroy, Dmitry Torokhov, Emmanuel Nicolet, Erhard F.,
Gautham R. Shenoy, Geoff Levand, George Spelvin, Greg Kurz, Gustavo A.
R. Silva, Gustavo Walbon, Haren Myneni, Hari Bathini, Joel Stanley,
Jordan Niethe, Kajol Jain, Kees Cook, Leonardo Bras, Madhavan
Srinivasan., Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Michal
Simek, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
Oliver O'Halloran, Paul Mackerras, Pingfan Liu, Qian Cai, Ram Pai,
Raphael Moreira Zinsly, Ravi Bangoria, Sam Bobroff, Sandipan Das, Segher
Boessenkool, Stephen Rothwell, Sukadev Bhattiprolu, Tyrel Datwyler,
Wolfram Sang, Xiongfeng Wang.

* tag 'powerpc-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (299 commits)
  powerpc/pseries: Make vio and ibmebus initcalls pseries specific
  cxl: Remove dead Kconfig options
  powerpc: Add POWER10 architected mode
  powerpc/dt_cpu_ftrs: Add MMA feature
  powerpc/dt_cpu_ftrs: Enable Prefixed Instructions
  powerpc/dt_cpu_ftrs: Advertise support for ISA v3.1 if selected
  powerpc: Add support for ISA v3.1
  powerpc: Add new HWCAP bits
  powerpc/64s: Don't set FSCR bits in INIT_THREAD
  powerpc/64s: Save FSCR to init_task.thread.fscr after feature init
  powerpc/64s: Don't let DT CPU features set FSCR_DSCR
  powerpc/64s: Don't init FSCR_DSCR in __init_FSCR()
  powerpc/32s: Fix another build failure with CONFIG_PPC_KUAP_DEBUG
  powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel
  powerpc/module_64: Simplify check for -mprofile-kernel ftrace relocations
  powerpc/module_64: Consolidate ftrace code
  powerpc/32: Disable KASAN with pages bigger than 16k
  powerpc/uaccess: Don't set KUEP by default on book3s/32
  powerpc/uaccess: Don't set KUAP by default on book3s/32
  powerpc/8xx: Reduce time spent in allow_user_access() and friends
  ...
 2020-06-05 12:39:30 -07:00
Linus Torvalds
084623e468 Modules updates for v5.8 
Summary of modules changes for the 5.8 merge window:
 
 - Harden CONFIG_STRICT_MODULE_RWX by rejecting any module that has
   SHF_WRITE|SHF_EXECINSTR sections
 - Remove and clean up nested #ifdefs, as it makes code hard to read
 
 Signed-off-by: Jessica Yu <jeyu@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEVrp26glSWYuDNrCUwEV+OM47wXIFAl7Z+qkQHGpleXVAa2Vy
 bmVsLm9yZwAKCRDARX44zjvBcm+vEACo/JelhaEDjjLzVuTBN4FQfXgBRbh6CGeF
 br7J1VtI9B0Coun0wfrDewwDieB2uHXQqivdC+KzNGXrBVhvFNLWuTTFcG7yce0K
 KZlbVREpiTRlenEa6A5EdIdvH0Ttg/+PFfkvOvvQOrbx5woZKptG49VdII9mhPuE
 LKnZk1xrK6jQLbOCPtUjyfB+eLqi0swhwstcfdIPUXsi2HtuLKmu7JPRpbW3Yz1v
 0Y9xix7ByTSg+wsphiKgvDnoJ9TYC3bFlAwpw+A+tsOKE0pmyetWKvkJ/hH42W9D
 7w6odSlG85d4ZExO2K8fHHsKmW2HgWx0cgLFf91sXCALqRYNjwTRkXH2OBXggLsz
 n3k8PmTRkDwS1oElrNG9E4LjKhjFbZZpP4kz+VlVe7YAsnlYpOBOcroTuaiuSV/A
 xmAP6mHgVAeUugwF5vHAPV4mwGJBLUVcvHENzge4jnyl/rSHsWE7hhwLnik9qkua
 cWINAVhBJpQvk3nrDr0dmUAXRJ7CXXtyPBbNh8ivvA4XeDNBLcYr8mcHPLpAoN4C
 xVcTRBxDXTRkw246zlQRcTySVpovtSv2C+IiaaHxA3j7lo4C1xhj6ihUIKz3Z1/A
 70zvBxmg3zpMwZWiRGeasAIu69a0qvBh0AOfVTbHBrIp5RokibtdoyuOu7ZGOU9B
 Un1WJNrSYQ==
 =OlVv
 -----END PGP SIGNATURE-----

Merge tag 'modules-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull module updates from Jessica Yu:

 - Harden CONFIG_STRICT_MODULE_RWX by rejecting any module that has
   SHF_WRITE|SHF_EXECINSTR sections

 - Remove and clean up nested #ifdefs, as it makes code hard to read

* tag 'modules-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: Harden STRICT_MODULE_RWX
  module: break nested ARCH_HAS_STRICT_MODULE_RWX and STRICT_MODULE_RWX #ifdefs
 2020-06-05 12:31:16 -07:00
Linus Torvalds
435faf5c21 RISC-V Patches for the 5.8 Merge Window, Part 1 
* The remainder of the code necessary to support the Kendryte K210.
     * Support for building device trees into the kernel, as the K210 doesn't
       have a bootloader that provides one.
     * A K210 device tree and the associated defconfig update.
     * Support for skipping PMP initialization on systems that trap on PMP
       accesses rather than treating them as WARL.
 * Support for KGDB.
 * Improvements to text patching.
 * Some cleanups to the SiFive L2 cache driver.
 
 I may have a second part, but I wanted to get this out earlier rather than
 later as they've been ready to go for a while now.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAl7YRtMTHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRAuExnzX7sYif+oD/4kaoQqmiw0VvyFjBlPT/TC7OPbaoXO
 5WBegSEAl+oOq+fUtjHomzn6HaTW2cPNexsqC/KuGP1/QL0OQ23T5O18LaCmrGMd
 CvELeAcvu6G4kbRuHwF0U16hBI2A1xIYVUJ8qmbuHPpEwVel3AsP2RIjQ+bOvm7g
 fVTIrlzl1s1eTsOXdOJb3sFZtISHb7o3lHZmcplDva3N13x8E0FrjuoJhHv0f2mj
 kcmZcy3sr8luAkwAJmbqmdPuwYTlteMnucXdCUv/kG2SaPkBwU5TS+MN7No2ylXH
 v4vxjkuSyJ1db72pla6uUB/cYD+mh2YI4tjjvH93s3k4I/GZMCrqivXZW2QtxBdt
 na++GxK8e4FrBG+VCCCQvx2mqugpMFMDnZDt36N2BqwjOtEzO3W8GqjrKCovXtQf
 farlgAiuFNVcoo7VFdpNZE+N5elQa0GWf57csCqqMNN4J8JLaOgyS7ByozJ9b9/A
 1x4g7kQANnMvYiYAeV+C2YfBcK6x8gHEPlWio1QZqirW5la34VUEWa18+rQeSRMz
 DArKPauCR1GuYZZVUkkDI8cXj0Gs5fTXsYmn+WsIpjFHnDYeYVe6Ocmczxyb3o3O
 lQwm7+drHlSmMvgrOlWJMrIUbdiomgelDU/iD4PiZzKozC52yKDS6A5gzoG6uZSM
 UleeAIeVG/TDCw==
 =keTq
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.8-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - The remainder of the code necessary to support the Kendryte K210:

     * Support for building device trees into the kernel, as the K210
       doesn't have a bootloader that provides one

     * A K210 device tree and the associated defconfig update

     * Support for skipping PMP initialization on systems that trap on
       PMP accesses rather than treating them as WARL

 - Support for KGDB

 - Improvements to text patching

 - Some cleanups to the SiFive L2 cache driver

* tag 'riscv-for-linus-5.8-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  soc: sifive: l2 cache: Mark l2_get_priv_group as static
  soc: sifive: l2 cache: Eliminate an unsigned zero compare warning
  riscv: Add support to determine no. of L2 cache way enabled
  riscv: cacheinfo: Implement cache_get_priv_group with a generic ops structure
  riscv: Use text_mutex instead of patch_lock
  riscv: Use NOKPROBE_SYMBOL() instead of __krpobes annotation
  riscv: Remove the 'riscv_' prefix of function name
  riscv: Add SW single-step support for KDB
  riscv: Use the XML target descriptions to report 3 system registers
  riscv: Add KGDB support
  kgdb: Add kgdb_has_hit_break function
  RISC-V: Skip setting up PMPs on traps
  riscv: K210: Update defconfig
  riscv: K210: Add a built-in device tree
  riscv: Allow device trees to be built into the kernel
 2020-06-04 20:14:18 -07:00
Linus Torvalds
828f3e18e1 ARM/SoC: drivers for v5.7 
These are updates to SoC specific drivers that did not have
 another subsystem maintainer tree to go through for some
 reason:
 
 - Some bus and memory drivers for the MIPS P5600 based
   Baikal-T1 SoC that is getting added through the MIPS tree.
 
 - There are new soc_device identification drivers for TI K3,
   Qualcomm MSM8939
 
 - New reset controller drivers for NXP i.MX8MP, Renesas
   RZ/G1H, and Hisilicon hi6220
 
 - The SCMI firmware interface can now work across ARM SMC/HVC
   as a transport.
 
 - Mediatek platforms now use a new driver for their "MMSYS"
   hardware block that controls clocks and some other aspects
   in behalf of the media and gpu drivers.
 
 - Some Tegra processors have improved power management
   support, including getting woken up by the PMIC and cluster
   power down during idle.
 
 - A new v4l staging driver for Tegra is added.
 
 - Cleanups and minor bugfixes for TI, NXP, Hisilicon,
   Mediatek, and Tegra.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEo6/YBQwIrVS28WGKmmx57+YAGNkFAl7XvgAACgkQmmx57+YA
 GNmj/hAAnAJ/hYehLfgCe711HUntgeRkaoTVpCt8BJNMdxsa23sn3V6k5+WYn1uG
 PtlgpefZEMHLUEEVDegR4nZXLG0Pzu1SR12KW34YPcQKkNo/+vlQ9zYUajnJ/KX6
 10zdLSIzHfk1VtXKvvQQ8xFyE+S/trGmjC57E6gfoCUT3rl1maD+ccVXUBaz9oob
 wuMxGXQAl57mio5yT1OfSk6Fev39xRE2dN1hzP7KUYhsemZajBwBBW5wVJZCsCB8
 LCGmxVkavM7BV4r2NokbBDs5rlfedBl/P/IPd9Is5a5tuGUkSsVRG9zqShxYLGM3
 S06az6POQFwXKFJoUKW0dK/Koy0D7BK+vhUBPzFv4HZ8iDCVf6Jju2MJ02GMqHPj
 OOrXaCbLYrvN/edVUWeeFywqwMbYTRwC4DxyTq5m7HxEB004xTOhs0rX5aR0u4n1
 bbsR97LguolwH9iEMzd3F3jCiKBcMecH3lAh5WcrtwlFIRrNhbWoGDoA/4TuORFS
 b11rgsTRIJ5Vc++D1HnSnx0ZZvUzyluMvygdALnSgVah6xYe6KVw9Kg/wioAJ04G
 uSTidqP3qRhsyET2HQo7CxdVfZbKfP25iKCKrdhQziztKvhF8qrUmZKloXOodRw+
 ewYSRmv8c324OYYit1X43oAdW8dntq1XbSIauaqxEb4JC7x/xRY=
 =44Jc
 -----END PGP SIGNATURE-----

Merge tag 'arm-drivers-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM/SoC driver updates from Arnd Bergmann:
 "These are updates to SoC specific drivers that did not have another
  subsystem maintainer tree to go through for some reason:

   - Some bus and memory drivers for the MIPS P5600 based Baikal-T1 SoC
     that is getting added through the MIPS tree.

   - There are new soc_device identification drivers for TI K3, Qualcomm
     MSM8939

   - New reset controller drivers for NXP i.MX8MP, Renesas RZ/G1H, and
     Hisilicon hi6220

   - The SCMI firmware interface can now work across ARM SMC/HVC as a
     transport.

   - Mediatek platforms now use a new driver for their "MMSYS" hardware
     block that controls clocks and some other aspects in behalf of the
     media and gpu drivers.

   - Some Tegra processors have improved power management support,
     including getting woken up by the PMIC and cluster power down
     during idle.

   - A new v4l staging driver for Tegra is added.

   - Cleanups and minor bugfixes for TI, NXP, Hisilicon, Mediatek, and
     Tegra"

* tag 'arm-drivers-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (155 commits)
  clk: sprd: fix compile-testing
  bus: bt1-axi: Build the driver into the kernel
  bus: bt1-apb: Build the driver into the kernel
  bus: bt1-axi: Use sysfs_streq instead of strncmp
  bus: bt1-axi: Optimize the return points in the driver
  bus: bt1-apb: Use sysfs_streq instead of strncmp
  bus: bt1-apb: Use PTR_ERR_OR_ZERO to return from request-regs method
  bus: bt1-apb: Fix show/store callback identations
  bus: bt1-apb: Include linux/io.h
  dt-bindings: memory: Add Baikal-T1 L2-cache Control Block binding
  memory: Add Baikal-T1 L2-cache Control Block driver
  bus: Add Baikal-T1 APB-bus driver
  bus: Add Baikal-T1 AXI-bus driver
  dt-bindings: bus: Add Baikal-T1 APB-bus binding
  dt-bindings: bus: Add Baikal-T1 AXI-bus binding
  staging: tegra-video: fix V4L2 dependency
  tee: fix crypto select
  drivers: soc: ti: knav_qmss_queue: Make knav_gp_range_ops static
  soc: ti: add k3 platforms chipid module driver
  dt-bindings: soc: ti: add binding for k3 platforms chipid module
  ...
 2020-06-04 19:56:20 -07:00
Linus Torvalds
886d7de631 Merge branch 'akpm' (patches from Andrew) 
Merge yet more updates from Andrew Morton:

 - More MM work. 100ish more to go. Mike Rapoport's "mm: remove
   __ARCH_HAS_5LEVEL_HACK" series should fix the current ppc issue

 - Various other little subsystems

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits)
  lib/ubsan.c: fix gcc-10 warnings
  tools/testing/selftests/vm: remove duplicate headers
  selftests: vm: pkeys: fix multilib builds for x86
  selftests: vm: pkeys: use the correct page size on powerpc
  selftests/vm/pkeys: override access right definitions on powerpc
  selftests/vm/pkeys: test correct behaviour of pkey-0
  selftests/vm/pkeys: introduce a sub-page allocator
  selftests/vm/pkeys: detect write violation on a mapped access-denied-key page
  selftests/vm/pkeys: associate key on a mapped page and detect write violation
  selftests/vm/pkeys: associate key on a mapped page and detect access violation
  selftests/vm/pkeys: improve checks to determine pkey support
  selftests/vm/pkeys: fix assertion in test_pkey_alloc_exhaust()
  selftests/vm/pkeys: fix number of reserved powerpc pkeys
  selftests/vm/pkeys: introduce powerpc support
  selftests/vm/pkeys: introduce generic pkey abstractions
  selftests: vm: pkeys: use the correct huge page size
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really random
  selftests/vm/pkeys: fix assertion in pkey_disable_set/clear()
  selftests/vm/pkeys: fix pkey_disable_clear()
  selftests: vm: pkeys: add helpers for pkey bits
  ...
 2020-06-04 19:18:29 -07:00
Pengcheng Yang
341a7213e5 kernel/relay.c: fix read_pos error when multiple readers 
When reading, read_pos should start with bytes_consumed, not file->f_pos.
Because when there is more than one reader, the read_pos corresponding to
file->f_pos may have been consumed, which will cause the data that has
been consumed to be read and the bytes_consumed update error.

Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jann Horn <jannh@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>e
Link: http://lkml.kernel.org/r/1579691175-28949-1-git-send-email-yangpc@wangsu.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:26 -07:00
Daniel Axtens
54e200ab40 kernel/relay.c: handle alloc_percpu returning NULL in relay_open 
alloc_percpu() may return NULL, which means chan->buf may be set to NULL.
In that case, when we do *per_cpu_ptr(chan->buf, ...), we dereference an
invalid pointer:

  BUG: Unable to handle kernel data access at 0x7dae0000
  Faulting instruction address: 0xc0000000003f3fec
  ...
  NIP relay_open+0x29c/0x600
  LR relay_open+0x270/0x600
  Call Trace:
     relay_open+0x264/0x600 (unreliable)
     __blk_trace_setup+0x254/0x600
     blk_trace_setup+0x68/0xa0
     sg_ioctl+0x7bc/0x2e80
     do_vfs_ioctl+0x13c/0x1300
     ksys_ioctl+0x94/0x130
     sys_ioctl+0x48/0xb0
     system_call+0x5c/0x68

Check if alloc_percpu returns NULL.

This was found by syzkaller both on x86 and powerpc, and the reproducer
it found on powerpc is capable of hitting the issue as an unprivileged
user.

Fixes: 017c59c042 ("relay: Use per CPU constructs for the relay channel buffer pointers")
Reported-by: syzbot+1e925b4b836afe85a1c6@syzkaller-ppc64.appspotmail.com
Reported-by: syzbot+587b2421926808309d21@syzkaller-ppc64.appspotmail.com
Reported-by: syzbot+58320b7171734bf79d26@syzkaller.appspotmail.com
Reported-by: syzbot+d6074fb08bdb2e010520@syzkaller.appspotmail.com
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Akash Goel <akash.goel@intel.com>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Salvatore Bonaccorso <carnil@debian.org>
Cc: <stable@vger.kernel.org>	[4.10+]
Link: http://lkml.kernel.org/r/20191219121256.26480-1-dja@axtens.net
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:26 -07:00
Kefeng Wang
eac2cece45 kernel/kprobes.c: convert to use DEFINE_SEQ_ATTRIBUTE macro 
Use DEFINE_SEQ_ATTRIBUTE macro to simplify the code.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/20200509064031.181091-4-wangkefeng.wang@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:26 -07:00
Jason Yan
de83dbd97f user.c: make uidhash_table static 
Fix the following sparse warning:

  kernel/user.c:85:19: warning: symbol 'uidhash_table' was not declared.
  Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200413082146.22737-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:24 -07:00
David Hildenbrand
3fe4f4991a kexec_file: don't place kexec images on IORESOURCE_MEM_DRIVER_MANAGED 
Memory flagged with IORESOURCE_MEM_DRIVER_MANAGED is special - it won't be
part of the initial memmap of the kexec kernel and not all memory might be
accessible.  Don't place any kexec images onto it.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-4-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:23 -07:00
Andrey Konovalov
5ff3b30ab5 kcov: collect coverage from interrupts 
This change extends kcov remote coverage support to allow collecting
coverage from soft interrupts in addition to kernel background threads.

To collect coverage from code that is executed in softirq context, a part
of that code has to be annotated with kcov_remote_start/stop() in a
similar way as how it is done for global kernel background threads.  Then
the handle used for the annotations has to be passed to the
KCOV_REMOTE_ENABLE ioctl.

Internally this patch adjusts the __sanitizer_cov_trace_pc() compiler
inserted callback to not bail out when called from softirq context.
kcov_remote_start/stop() are updated to save/restore the current per task
kcov state in a per-cpu area (in case the softirq came when the kernel was
already collecting coverage in task context).  Coverage from softirqs is
collected into pre-allocated per-cpu areas, whose size is controlled by
the new CONFIG_KCOV_IRQ_AREA_SIZE.

[andreyknvl@google.com: turn current->kcov_softirq into unsigned int to fix objtool warning]
  Link: http://lkml.kernel.org/r/841c778aa3849c5cb8c3761f56b87ce653a88671.1585233617.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/469bd385c431d050bc38a593296eff4baae50666.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:20 -07:00
Andrey Konovalov
5fe7042dc0 kcov: use t->kcov_mode as enabled indicator 
Currently kcov_remote_start() and kcov_remote_stop() check t->kcov to find
out whether the coverage is already being collected by the current task.
Use t->kcov_mode for that instead.  This doesn't change the overall
behavior in any way, but serves as a preparation for the following softirq
coverage collection support patch.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/f70377945d1d8e6e4916cbce871a12303d6186b4.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/ee1a1dec43059da5d7664c85c1addc89c4cd58de.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:20 -07:00
Andrey Konovalov
eeb91f9a2e kcov: move t->kcov_sequence assignment 
Move t->kcov_sequence assignment before assigning t->kcov_mode for
consistency.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/5889efe35e0b300e69dba97216b1288d9c2428a8.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/f0283c676bab3335cb48bfe12d375a3da4719f59.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:20 -07:00
Andrey Konovalov
76484b1c77 kcov: move t->kcov assignments into kcov_start/stop 
Every time kcov_start/stop() is called, t->kcov is also assigned, so move
the assignment into the functions.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/6644839d3567df61ade3c4b246a46cacbe4f9e11.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/82625ef3ff878f0b585763cc31d09d9b08ca37d6.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:20 -07:00
Andrey Konovalov
67b3d3cca3 kcov: fix potential use-after-free in kcov_remote_start 
If vmalloc() fails in kcov_remote_start() we'll access remote->kcov
without holding kcov_remote_lock, so remote might potentially be freed at
that point.  Cache kcov pointer in a local variable.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/9d9134359725a965627b7e8f2652069f86f1d1fa.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/de0d3d30ff90776a2a509cc34c7c1c7521bda125.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:20 -07:00
Andrey Konovalov
3c61df3885 kcov: cleanup debug messages 
Patch series "kcov: collect coverage from usb soft interrupts", v4.

This patchset extends kcov to allow collecting coverage from soft
interrupts and then uses the new functionality to collect coverage from
USB code.

This has allowed to find at least one new HID bug [1], which was recently
fixed by Alan [2].

[1] https://syzkaller.appspot.com/bug?extid=09ef48aa58261464b621
[2] https://patchwork.kernel.org/patch/11283319/

Any subsystem that uses softirqs (e.g. timers) can make use of this in
the future. Looking at the recent syzbot reports, an obvious candidate
is the networking subsystem [3, 4, 5 and many more].

[3] https://syzkaller.appspot.com/bug?extid=522ab502c69badc66ab7
[4] https://syzkaller.appspot.com/bug?extid=57f89d05946c53dbbb31
[5] https://syzkaller.appspot.com/bug?extid=df358e65d9c1b9d3f5f4

This pach (of 7):

Previous commit left a lot of excessive debug messages, clean them up.

Link; http://lkml.kernel.org/r/cover.1585233617.git.andreyknvl@google.com
Link; http://lkml.kernel.org/r/ab5e2885ce674ba6e04368551e51eeb6a2c11baf.1585233617.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/4a497134b2cf7a9d306d28e3dd2746f5446d1605.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-04 19:06:20 -07:00
Linus Torvalds
15a2bc4dbb Merge branch 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 
Pull execve updates from Eric Biederman:
 "Last cycle for the Nth time I ran into bugs and quality of
  implementation issues related to exec that could not be easily be
  fixed because of the way exec is implemented. So I have been digging
  into exec and cleanup up what I can.

  I don't think I have exec sorted out enough to fix the issues I
  started with but I have made some headway this cycle with 4 sets of
  changes.

   - promised cleanups after introducing exec_update_mutex

   - trivial cleanups for exec

   - control flow simplifications

   - remove the recomputation of bprm->cred

  The net result is code that is a bit easier to understand and work
  with and a decrease in the number of lines of code (if you don't count
  the added tests)"

* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (24 commits)
  exec: Compute file based creds only once
  exec: Add a per bprm->file version of per_clear
  binfmt_elf_fdpic: fix execfd build regression
  selftests/exec: Add binfmt_script regression test
  exec: Remove recursion from search_binary_handler
  exec: Generic execfd support
  exec/binfmt_script: Don't modify bprm->buf and then return -ENOEXEC
  exec: Move the call of prepare_binprm into search_binary_handler
  exec: Allow load_misc_binary to call prepare_binprm unconditionally
  exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds
  exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds
  exec: Teach prepare_exec_creds how exec treats uids & gids
  exec: Set the point of no return sooner
  exec: Move handling of the point of no return to the top level
  exec: Run sync_mm_rss before taking exec_update_mutex
  exec: Fix spelling of search_binary_handler in a comment
  exec: Move the comment from above de_thread to above unshare_sighand
  exec: Rename flush_old_exec begin_new_exec
  exec: Move most of setup_new_exec into flush_old_exec
  exec: In setup_new_exec cache current in the local variable me
  ...
 2020-06-04 14:07:08 -07:00
Linus Torvalds
9ff7258575 Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 
Pull proc updates from Eric Biederman:
 "This has four sets of changes:

   - modernize proc to support multiple private instances

   - ensure we see the exit of each process tid exactly

   - remove has_group_leader_pid

   - use pids not tasks in posix-cpu-timers lookup

  Alexey updated proc so each mount of proc uses a new superblock. This
  allows people to actually use mount options with proc with no fear of
  messing up another mount of proc. Given the kernel's internal mounts
  of proc for things like uml this was a real problem, and resulted in
  Android's hidepid mount options being ignored and introducing security
  issues.

  The rest of the changes are small cleanups and fixes that came out of
  my work to allow this change to proc. In essence it is swapping the
  pids in de_thread during exec which removes a special case the code
  had to handle. Then updating the code to stop handling that special
  case"

* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: proc_pid_ns takes super_block as an argument
  remove the no longer needed pid_alive() check in __task_pid_nr_ns()
  posix-cpu-timers: Replace __get_task_for_clock with pid_for_clock
  posix-cpu-timers: Replace cpu_timer_pid_type with clock_pid_type
  posix-cpu-timers: Extend rcu_read_lock removing task_struct references
  signal: Remove has_group_leader_pid
  exec: Remove BUG_ON(has_group_leader_pid)
  posix-cpu-timer:  Unify the now redundant code in lookup_task
  posix-cpu-timer: Tidy up group_leader logic in lookup_task
  proc: Ensure we see the exit of each process tid exactly once
  rculist: Add hlists_swap_heads_rcu
  proc: Use PIDTYPE_TGID in next_tgid
  Use proc_pid_ns() to get pid_namespace from the proc superblock
  proc: use named enums for better readability
  proc: use human-readable values for hidepid
  docs: proc: add documentation for "hidepid=4" and "subset=pid" options and new mount behavior
  proc: add option to mount only a pids subset
  proc: instantiate only pids that we can ptrace on 'hidepid=4' mount option
  proc: allow to mount many instances of proc in one pid namespace
  proc: rename struct proc_fs_info to proc_fs_opts
 2020-06-04 13:54:34 -07:00
Linus Torvalds
9fb4c5250f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching 
Pull livepatching updates from Jiri Kosina:

 - simplifications and improvements for issues Peter Ziljstra found
   during his previous work on W^X cleanups.

   This allows us to remove livepatch arch-specific .klp.arch sections
   and add proper support for jump labels in patched code.

   Also, this patchset removes the last module_disable_ro() usage in the
   tree.

   Patches from Josh Poimboeuf and Peter Zijlstra

 - a few other minor cleanups

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
  MAINTAINERS: add lib/livepatch to LIVE PATCHING
  livepatch: add arch-specific headers to MAINTAINERS
  livepatch: Make klp_apply_object_relocs static
  MAINTAINERS: adjust to livepatch .klp.arch removal
  module: Make module_enable_ro() static again
  x86/module: Use text_mutex in apply_relocate_add()
  module: Remove module_disable_ro()
  livepatch: Remove module_disable_ro() usage
  x86/module: Use text_poke() for late relocations
  s390/module: Use s390_kernel_write() for late relocations
  s390: Change s390_kernel_write() return type to match memcpy()
  livepatch: Prevent module-specific KLP rela sections from referencing vmlinux symbols
  livepatch: Remove .klp.arch
  livepatch: Apply vmlinux-specific KLP relocations early
  livepatch: Disallow vmlinux.ko
 2020-06-04 11:13:03 -07:00
Linus Torvalds
ee01c4d72a Merge branch 'akpm' (patches from Andrew) 
Merge more updates from Andrew Morton:
 "More mm/ work, plenty more to come

  Subsystems affected by this patch series: slub, memcg, gup, kasan,
  pagealloc, hugetlb, vmscan, tools, mempolicy, memblock, hugetlbfs,
  thp, mmap, kconfig"

* akpm: (131 commits)
  arm64: mm: use ARCH_HAS_DEBUG_WX instead of arch defined
  x86: mm: use ARCH_HAS_DEBUG_WX instead of arch defined
  riscv: support DEBUG_WX
  mm: add DEBUG_WX support
  drivers/base/memory.c: cache memory blocks in xarray to accelerate lookup
  mm/thp: rename pmd_mknotpresent() as pmd_mkinvalid()
  powerpc/mm: drop platform defined pmd_mknotpresent()
  mm: thp: don't need to drain lru cache when splitting and mlocking THP
  hugetlbfs: get unmapped area below TASK_UNMAPPED_BASE for hugetlbfs
  sparc32: register memory occupied by kernel as memblock.memory
  include/linux/memblock.h: fix minor typo and unclear comment
  mm, mempolicy: fix up gup usage in lookup_node
  tools/vm/page_owner_sort.c: filter out unneeded line
  mm: swap: memcg: fix memcg stats for huge pages
  mm: swap: fix vmstats for huge pages
  mm: vmscan: limit the range of LRU type balancing
  mm: vmscan: reclaim writepage is IO cost
  mm: vmscan: determine anon/file pressure balance at the reclaim root
  mm: balance LRU lists based on relative thrashing
  mm: only count actual rotations as LRU reclaim cost
  ...
 2020-06-03 20:24:15 -07:00
Johannes Weiner
c843966c55 mm: allow swappiness that prefers reclaiming anon over the file workingset 
With the advent of fast random IO devices (SSDs, PMEM) and in-memory swap
devices such as zswap, it's possible for swap to be much faster than
filesystems, and for swapping to be preferable over thrashing filesystem
caches.

Allow setting swappiness - which defines the rough relative IO cost of
cache misses between page cache and swap-backed pages - to reflect such
situations by making the swap-preferred range configurable.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Link: http://lkml.kernel.org/r/20200520232525.798933-4-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:48 -07:00
Johannes Weiner
d9eb1ea2bf mm: memcontrol: delete unused lrucare handling 
Swapin faults were the last event to charge pages after they had already
been put on the LRU list.  Now that we charge directly on swapin, the
lrucare portion of the charge code is unused.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Shakeel Butt <shakeelb@google.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-19-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:48 -07:00
Johannes Weiner
9d82c69438 mm: memcontrol: convert anon and file-thp to new mem_cgroup_charge() API 
With the page->mapping requirement gone from memcg, we can charge anon and
file-thp pages in one single step, right after they're allocated.

This removes two out of three API calls - especially the tricky commit
step that needed to happen at just the right time between when the page is
"set up" and when it's "published" - somewhat vague and fluid concepts
that varied by page type.  All we need is a freshly allocated page and a
memcg context to charge.

v2: prevent double charges on pre-allocated hugepages in khugepaged

[hannes@cmpxchg.org: Fix crash - *hpage could be ERR_PTR instead of NULL]
  Link: http://lkml.kernel.org/r/20200512215813.GA487759@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/20200508183105.225460-13-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:48 -07:00
Johannes Weiner
be5d0a74c6 mm: memcontrol: switch to native NR_ANON_MAPPED counter 
Memcg maintains a private MEMCG_RSS counter.  This divergence from the
generic VM accounting means unnecessary code overhead, and creates a
dependency for memcg that page->mapping is set up at the time of charging,
so that page types can be told apart.

Convert the generic accounting sites to mod_lruvec_page_state and friends
to maintain the per-cgroup vmstat counter of NR_ANON_MAPPED.  We use
lock_page_memcg() to stabilize page->mem_cgroup during rmap changes, the
same way we do for NR_FILE_MAPPED.

With the previous patch removing MEMCG_CACHE and the private NR_SHMEM
counter, this patch finally eliminates the need to have page->mapping set
up at charge time.  However, we need to have page->mem_cgroup set up by
the time rmap runs and does the accounting, so switch the commit and the
rmap callbacks around.

v2: fix temporary accounting bug by switching rmap<->commit (Joonsoo)

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-11-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:47 -07:00
Johannes Weiner
3fba69a56e mm: memcontrol: drop @compound parameter from memcg charging API 
The memcg charging API carries a boolean @compound parameter that tells
whether the page we're dealing with is a hugepage.
mem_cgroup_commit_charge() has another boolean @lrucare that indicates
whether the page needs LRU locking or not while charging.  The majority of
callsites know those parameters at compile time, which results in a lot of
naked "false, false" argument lists.  This makes for cryptic code and is a
breeding ground for subtle mistakes.

Thankfully, the huge page state can be inferred from the page itself and
doesn't need to be passed along.  This is safe because charging completes
before the page is published and somebody may split it.

Simplify the callsites by removing @compound, and let memcg infer the
state by using hpage_nr_pages() unconditionally.  That function does
PageTransHuge() to identify huge pages, which also helpfully asserts that
nobody passes in tail pages by accident.

The following patches will introduce a new charging API, best not to carry
over unnecessary weight.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-4-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:47 -07:00
Daniel Jordan
004ed42638 padata: add basic support for multithreaded jobs 
Sometimes the kernel doesn't take full advantage of system memory
bandwidth, leading to a single CPU spending excessive time in
initialization paths where the data scales with memory size.

Multithreading naturally addresses this problem.

Extend padata, a framework that handles many parallel yet singlethreaded
jobs, to also handle multithreaded jobs by adding support for splitting up
the work evenly, specifying a minimum amount of work that's appropriate
for one helper thread to do, load balancing between helpers, and
coordinating them.

This is inspired by work from Pavel Tatashin and Steve Sistare.

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Josh Triplett <josh@joshtriplett.org>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200527173608.2885243-5-daniel.m.jordan@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:45 -07:00
Daniel Jordan
4611ce2246 padata: allocate work structures for parallel jobs from a pool 
padata allocates per-CPU, per-instance work structs for parallel jobs.  A
do_parallel call assigns a job to a sequence number and hashes the number
to a CPU, where the job will eventually run using the corresponding work.

This approach fit with how padata used to bind a job to each CPU
round-robin, makes less sense after commit bfde23ce20 ("padata: unbind
parallel jobs from specific CPUs") because a work isn't bound to a
particular CPU anymore, and isn't needed at all for multithreaded jobs
because they don't have sequence numbers.

Replace the per-CPU works with a preallocated pool, which allows sharing
them between existing padata users and the upcoming multithreaded user.
The pool will also facilitate setting NUMA-aware concurrency limits with
later users.

The pool is sized according to the number of possible CPUs.  With this
limit, MAX_OBJ_NUM no longer makes sense, so remove it.

If the global pool is exhausted, a parallel job is run in the current task
instead to throttle a system trying to do too much in parallel.

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Josh Triplett <josh@joshtriplett.org>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200527173608.2885243-4-daniel.m.jordan@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:45 -07:00
Daniel Jordan
f1b192b117 padata: initialize earlier 
padata will soon initialize the system's struct pages in parallel, so it
needs to be ready by page_alloc_init_late().

The error return from padata_driver_init() triggers an initcall warning,
so add a warning to padata_init() to avoid silent failure.

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Josh Triplett <josh@joshtriplett.org>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200527173608.2885243-3-daniel.m.jordan@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:45 -07:00
Daniel Jordan
305dacf779 padata: remove exit routine 
Patch series "padata: parallelize deferred page init", v3.

Deferred struct page init is a bottleneck in kernel boot--the biggest for
us and probably others.  Optimizing it maximizes availability for
large-memory systems and allows spinning up short-lived VMs as needed
without having to leave them running.  It also benefits bare metal
machines hosting VMs that are sensitive to downtime.  In projects such as
VMM Fast Restart[1], where guest state is preserved across kexec reboot,
it helps prevent application and network timeouts in the guests.

So, multithread deferred init to take full advantage of system memory
bandwidth.

Extend padata, a framework that handles many parallel singlethreaded jobs,
to handle multithreaded jobs as well by adding support for splitting up
the work evenly, specifying a minimum amount of work that's appropriate
for one helper thread to do, load balancing between helpers, and
coordinating them.  More documentation in patches 4 and 8.

This series is the first step in a project to address other memory
proportional bottlenecks in the kernel such as pmem struct page init, vfio
page pinning, hugetlb fallocate, and munmap.  Deferred page init doesn't
require concurrency limits, resource control, or priority adjustments like
these other users will because it happens during boot when the system is
otherwise idle and waiting for page init to finish.

This has been run on a variety of x86 systems and speeds up kernel boot by
4% to 49%, saving up to 1.6 out of 4 seconds.  Patch 6 has more numbers.

This patch (of 8):

padata_driver_exit() is unnecessary because padata isn't built as a module
and doesn't exit.

padata's init routine will soon allocate memory, so getting rid of the
exit function now avoids pointless code to free it.

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Josh Triplett <josh@joshtriplett.org>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200527173608.2885243-1-daniel.m.jordan@oracle.com
Link: http://lkml.kernel.org/r/20200527173608.2885243-2-daniel.m.jordan@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2020-06-03 20:09:45 -07:00