Use the newly added SYM_CODE_START_LOCAL* to annotate beginnings of
all pseudo-functions (those ending with END until now) which do not
have ".globl" annotation. This is needed to balance END for tools that
generate debuginfo. Note that ENDs are switched to SYM_CODE_END too so
that everybody can see the pairing.

C-like functions (which handle frame ptr etc.) are not annotated here,
hence SYM_CODE_* macros are used here, not SYM_FUNC_*. Note that the
32bit version of early_idt_handler_common already had ENDPROC -- switch
that to SYM_CODE_END for the same reason as above (and to be the same as
64bit).

While early_idt_handler_common is LOCAL, it's name is not prepended with
".L" as it happens to appear in call traces.

bad_get_user*, and bad_put_user are now aligned, as they are separate
functions. They do not mind to be aligned -- no need to be compact
there.

early_idt_handler_common is aligned now too, as it is after
early_idt_handler_array, so as well no need to be compact there.

verify_cpu is self-standing and included in other .S files, so align it
too.

The others have alignment preserved to what it used to be (using the
_NOALIGN variant of macros).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexios Zavras <alexios.zavras@intel.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: Enrico Weigelt <info@metux.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: linux-arch@vger.kernel.org
Cc: Maran Wilson <maran.wilson@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191011115108.12392-6-jslaby@suse.cz

Place SYM_*_START_NOALIGN and SYM_*_END around the THUNK macro body.
Preserve @function by FUNC (64bit) and CODE (32bit). Given it was not
marked as aligned, use NOALIGN.

The result:
 Value  Size Type    Bind   Vis      Ndx Name
  0000    28 FUNC    GLOBAL DEFAULT    1 trace_hardirqs_on_thunk
  001c    28 FUNC    GLOBAL DEFAULT    1 trace_hardirqs_off_thunk
  0038    24 FUNC    GLOBAL DEFAULT    1 lockdep_sys_exit_thunk
  0050    24 FUNC    GLOBAL DEFAULT    1 ___preempt_schedule
  0068    24 FUNC    GLOBAL DEFAULT    1 ___preempt_schedule_notra

The annotation of .L_restore does not generate anything (at the moment).
Here, it just serves documentation purposes (as opening and closing
brackets of functions).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191011115108.12392-5-jslaby@suse.cz

There are functions in relocate_kernel_{32,64}.c which are not
annotated. This makes automatic annotations on them rather hard. So
annotate all the functions now.

Note that these are not C-like functions, so FUNC is not used. Instead
CODE markers are used. Also the functions are not aligned, so the
NOALIGN versions are used:

- SYM_CODE_START_NOALIGN
- SYM_CODE_START_LOCAL_NOALIGN
- SYM_CODE_END

The result is:
  0000   108 NOTYPE  GLOBAL DEFAULT    1 relocate_kernel
  006c   165 NOTYPE  LOCAL  DEFAULT    1 identity_mapped
  0146   127 NOTYPE  LOCAL  DEFAULT    1 swap_pages
  0111    53 NOTYPE  LOCAL  DEFAULT    1 virtual_mapped
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexios Zavras <alexios.zavras@intel.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Enrico Weigelt <info@metux.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191011115108.12392-4-jslaby@suse.cz

Some global data in the suspend code were marked as `ENTRY'. ENTRY was
intended for functions and shall be paired with ENDPROC. ENTRY also
aligns symbols to 16 bytes which creates unnecessary holes.

Note that:

* saved_magic (long) in wakeup_32 is still prepended by section's ALIGN
* saved_magic (quad) in wakeup_64 follows a bunch of quads which are
  aligned (but need not be aligned to 16)

Since historical markings are being dropped, make proper use of newly
added SYM_DATA in this code.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191011115108.12392-3-jslaby@suse.cz

Introduce new C macros for annotations of functions and data in
assembly. There is a long-standing mess in macros like ENTRY, END,
ENDPROC and similar. They are used in different manners and sometimes
incorrectly.

So introduce macros with clear use to annotate assembly as follows:

a) Support macros for the ones below
   SYM_T_FUNC -- type used by assembler to mark functions
   SYM_T_OBJECT -- type used by assembler to mark data
   SYM_T_NONE -- type used by assembler to mark entries of unknown type

   They are defined as STT_FUNC, STT_OBJECT, and STT_NOTYPE
   respectively. According to the gas manual, this is the most portable
   way. I am not sure about other assemblers, so this can be switched
   back to %function and %object if this turns into a problem.
   Architectures can also override them by something like ", @function"
   if they need.

   SYM_A_ALIGN, SYM_A_NONE -- align the symbol?
   SYM_L_GLOBAL, SYM_L_WEAK, SYM_L_LOCAL -- linkage of symbols

b) Mostly internal annotations, used by the ones below
   SYM_ENTRY -- use only if you have to (for non-paired symbols)
   SYM_START -- use only if you have to (for paired symbols)
   SYM_END -- use only if you have to (for paired symbols)

c) Annotations for code
   SYM_INNER_LABEL_ALIGN -- only for labels in the middle of code
   SYM_INNER_LABEL -- only for labels in the middle of code

   SYM_FUNC_START_LOCAL_ALIAS -- use where there are two local names for
	one function
   SYM_FUNC_START_ALIAS -- use where there are two global names for one
	function
   SYM_FUNC_END_ALIAS -- the end of LOCAL_ALIASed or ALIASed function

   SYM_FUNC_START -- use for global functions
   SYM_FUNC_START_NOALIGN -- use for global functions, w/o alignment
   SYM_FUNC_START_LOCAL -- use for local functions
   SYM_FUNC_START_LOCAL_NOALIGN -- use for local functions, w/o
	alignment
   SYM_FUNC_START_WEAK -- use for weak functions
   SYM_FUNC_START_WEAK_NOALIGN -- use for weak functions, w/o alignment
   SYM_FUNC_END -- the end of SYM_FUNC_START_LOCAL, SYM_FUNC_START,
	SYM_FUNC_START_WEAK, ...

   For functions with special (non-C) calling conventions:
   SYM_CODE_START -- use for non-C (special) functions
   SYM_CODE_START_NOALIGN -- use for non-C (special) functions, w/o
	alignment
   SYM_CODE_START_LOCAL -- use for local non-C (special) functions
   SYM_CODE_START_LOCAL_NOALIGN -- use for local non-C (special)
	functions, w/o alignment
   SYM_CODE_END -- the end of SYM_CODE_START_LOCAL or SYM_CODE_START

d) For data
   SYM_DATA_START -- global data symbol
   SYM_DATA_START_LOCAL -- local data symbol
   SYM_DATA_END -- the end of the SYM_DATA_START symbol
   SYM_DATA_END_LABEL -- the labeled end of SYM_DATA_START symbol
   SYM_DATA -- start+end wrapper around simple global data
   SYM_DATA_LOCAL -- start+end wrapper around simple local data

==========

The macros allow to pair starts and ends of functions and mark functions
correctly in the output ELF objects.

All users of the old macros in x86 are converted to use these in further
patches.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20191011115108.12392-2-jslaby@suse.cz

During the assembly cleanup patchset review, I found more symbols which
are used only locally. So make them really local by prepending ".L" to
them. Namely:

 - wakeup_idt is used only in realmode/rm/wakeup_asm.S.
 - in_pm32 is used only in boot/pmjump.S.
 - retint_user is used only in entry/entry_64.S, perhaps since commit
   2ec67971 ("x86/entry/64/compat: Remove most of the fast system
   call machinery"), where entry_64_compat's caller was removed.

Drop GLOBAL from all of them too. I do not see more candidates in the
series.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20191011092213.31470-1-jslaby@suse.czSigned-off-by: Ingo Molnar <mingo@kernel.org>

As far as I can see, it was never used outside of head_32.S. Not even
when added in 2004. So make it local.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191003095238.29831-2-jslaby@suse.cz

Moving early_recursion_flag (4 bytes) after early_level4_pgt (4k) and
early_dynamic_pgts (256k) saves 4k which are used for alignment of
early_level4_pgt after early_recursion_flag.

The real improvement is merely on the source code side. Previously it
was:
* __INITDATA + .balign
* early_recursion_flag variable
* a ton of CPP MACROS
* __INITDATA (again)
* early_top_pgt and early_recursion_flag variables
* .data

Now, it is a bit simpler:
* a ton of CPP MACROS
* __INITDATA + .balign
* early_top_pgt and early_recursion_flag variables
* early_recursion_flag variable
* .data

On the binary level the change looks like this:
Before:
 (sections)
  12 .init.data    00042000  0000000000000000  0000000000000000 00008000  2**12
 (symbols)
  000000       4 OBJECT  GLOBAL DEFAULT   22 early_recursion_flag
  001000    4096 OBJECT  GLOBAL DEFAULT   22 early_top_pgt
  002000 0x40000 OBJECT  GLOBAL DEFAULT   22 early_dynamic_pgts

After:
 (sections)
  12 .init.data    00041004  0000000000000000  0000000000000000 00008000  2**12
 (symbols)
  000000    4096 OBJECT  GLOBAL DEFAULT   22 early_top_pgt
  001000 0x40000 OBJECT  GLOBAL DEFAULT   22 early_dynamic_pgts
  041000       4 OBJECT  GLOBAL DEFAULT   22 early_recursion_flag

So the resulting vmlinux is smaller by 4k with my toolchain as many
other variables can be placed after early_recursion_flag to fill the
rest of the page. Note that this is only .init data, so it is freed
right after being booted anyway. Savings on-disk are none -- compression
of zeros is easy, so the size of bzImage is the same pre and post the
change.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191003095238.29831-1-jslaby@suse.cz

Pull btrfs fixes from David Sterba:
 "A bunch of fixes that accumulated in recent weeks, mostly material for
  stable.

  Summary:

   - fix for regression from 5.3 that prevents to use balance convert
     with single profile

   - qgroup fixes: rescan race, accounting leak with multiple writers,
     potential leak after io failure recovery

   - fix for use after free in relocation (reported by KASAN)

   - other error handling fixups"

* tag 'for-5.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: qgroup: Fix reserved data space leak if we have multiple reserve calls
  btrfs: qgroup: Fix the wrong target io_tree when freeing reserved data space
  btrfs: Fix a regression which we can't convert to SINGLE profile
  btrfs: relocation: fix use-after-free on dead relocation roots
  Btrfs: fix race setting up and completing qgroup rescan workers
  Btrfs: fix missing error return if writeback for extent buffer never started
  btrfs: adjust dirty_metadata_bytes after writeback failure of extent buffer
  Btrfs: fix selftests failure due to uninitialized i_mode in test inodes

Pull csky updates from Guo Ren:
 "This round of csky subsystem just some fixups:

   - Fix mb() synchronization problem

   - Fix dma_alloc_coherent with PAGE_SO attribute

   - Fix cache_op failed when cross memory ZONEs

   - Optimize arch_sync_dma_for_cpu/device with dma_inv_range

   - Fix ioremap function losing

   - Fix arch_get_unmapped_area() implementation

   - Fix defer cache flush for 610

   - Support kernel non-aligned access

   - Fix 610 vipt cache flush mechanism

   - Fix add zero_fp fixup perf backtrace panic

   - Move static keyword to the front of declaration

   - Fix csky_pmu.max_period assignment

   - Use generic free_initrd_mem()

   - entry: Remove unneeded need_resched() loop"

* tag 'csky-for-linus-5.4-rc1' of git://github.com/c-sky/csky-linux:
  csky: Move static keyword to the front of declaration
  csky: entry: Remove unneeded need_resched() loop
  csky: Fixup csky_pmu.max_period assignment
  csky: Fixup add zero_fp fixup perf backtrace panic
  csky: Use generic free_initrd_mem()
  csky: Fixup 610 vipt cache flush mechanism
  csky: Support kernel non-aligned access
  csky: Fixup defer cache flush for 610
  csky: Fixup arch_get_unmapped_area() implementation
  csky: Fixup ioremap function losing
  csky: Optimize arch_sync_dma_for_cpu/device with dma_inv_range
  csky/dma: Fixup cache_op failed when cross memory ZONEs
  csky: Fixup dma_alloc_coherent with PAGE_SO attribute
  csky: Fixup mb() synchronization problem

Pull ARM SoC fixes from Olof Johansson:
 "A few fixes that have trickled in through the merge window:

   - Video fixes for OMAP due to panel-dpi driver removal

   - Clock fixes for OMAP that broke no-idle quirks + nfsroot on DRA7

   - Fixing arch version on ASpeed ast2500

   - Two fixes for reset handling on ARM SCMI"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  ARM: aspeed: ast2500 is ARMv6K
  reset: reset-scmi: add missing handle initialisation
  firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset
  bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle()
  ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
  ARM: dts: am3517-evm: Fix missing video
  ARM: dts: logicpd-torpedo-baseboard: Fix missing video
  ARM: omap2plus_defconfig: Fix missing video
  bus: ti-sysc: Fix handling of invalid clocks
  bus: ti-sysc: Fix clock handling for no-idle quirks

Pull tracing fixes from Steven Rostedt:
 "A few more tracing fixes:

   - Fix a buffer overflow by checking nr_args correctly in probes

   - Fix a warning that is reported by clang

   - Fix a possible memory leak in error path of filter processing

   - Fix the selftest that checks for failures, but wasn't failing

   - Minor clean up on call site output of a memory trace event"

* tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Fix same probe error test
  mm, tracing: Print symbol name for call_site in trace events
  tracing: Have error path in predicate_parse() free its allocated memory
  tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
  tracing/probe: Fix to check the difference of nr_args before adding probe

Pull more MMC updates from Ulf Hansson:
 "A couple more updates/fixes for MMC:

   - sdhci-pci: Add Genesys Logic GL975x support

   - sdhci-tegra: Recover loss in throughput for DMA

   - sdhci-of-esdhc: Fix DMA bug"

* tag 'mmc-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: host: sdhci-pci: Add Genesys Logic GL975x support
  mmc: tegra: Implement ->set_dma_mask()
  mmc: sdhci: Let drivers define their DMA mask
  mmc: sdhci-of-esdhc: set DMA snooping based on DMA coherence
  mmc: sdhci: improve ADMA error reporting

Move the static keyword to the front of declaration of
csky_pmu_of_device_ids, and resolve the following compiler
warning that can be seen when building with warnings
enabled (W=1):

arch/csky/kernel/perf_event.c:1340:1: warning:
  ‘static’ is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

Since the enabling and disabling of IRQs within preempt_schedule_irq()
is contained in a need_resched() loop, we don't need the outer arch
code loop.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

Pull Documentation/process update from Greg KH:
 "Here are two small Documentation/process/embargoed-hardware-issues.rst
  file updates that missed my previous char/misc pull request.

  The first one adds an Intel representative for the process, and the
  second one cleans up the text a bit more when it comes to how the
  disclosure rules work, as it was a bit confusing to some companies"

* tag 'char-misc-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Documentation/process: Clarify disclosure rules
  Documentation/process: Volunteer as the ambassador for Intel

Pull more vfs updates from Al Viro:
 "A couple of misc patches"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  afs dynroot: switch to simple_dir_operations
  fs/handle.c - fix up kerneldoc

Pull more cifs updates from Steve French:
 "Fixes from the recent SMB3 Test events and Storage Developer
  Conference (held the last two weeks).

  Here are nine smb3 patches including an important patch for debugging
  traces with wireshark, with three patches marked for stable.

  Additional fixes from last week to better handle some newly discovered
  reparse points, and a fix the create/mkdir path for setting the mode
  more atomically (in SMB3 Create security descriptor context), and one
  for path name processing are still being tested so are not included
  here"

* tag '5.4-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix oplock handling for SMB 2.1+ protocols
  smb3: missing ACL related flags
  smb3: pass mode bits into create calls
  smb3: Add missing reparse tags
  CIFS: fix max ea value size
  fs/cifs/sess.c: Remove set but not used variable 'capabilities'
  fs/cifs/smb2pdu.c: Make SMB2_notify_init static
  smb3: fix leak in "open on server" perf counter
  smb3: allow decryption keys to be dumped by admin for debugging

The csky_pmu.max_period has type u64, and BIT() can only return
32 bits unsigned long on C-SKY. The initialization for max_period
will be incorrect when count_width is bigger than 32.

Use BIT_ULL()
Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>

We need set fp zero to let backtrace know the end. The patch fixup perf
callchain panic problem, because backtrace didn't know what is the end
of fp.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reported-by: Mao Han <han_mao@c-sky.com>

The csky implementation of free_initrd_mem() is an open-coded version of
free_reserved_area() without poisoning.

Remove it and make csky use the generic version of free_initrd_mem().
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

Merge active entropy generation updates.

This is admittedly partly "for discussion".  We need to have a way
forward for the boot time deadlocks where user space ends up waiting for
more entropy, but no entropy is forthcoming because the system is
entirely idle just waiting for something to happen.

While this was triggered by what is arguably a user space bug with
GDM/gnome-session asking for secure randomness during early boot, when
they didn't even need any such truly secure thing, the issue ends up
being that our "getrandom()" interface is prone to that kind of
confusion, because people don't think very hard about whether they want
to block for sufficient amounts of entropy.

The approach here-in is to decide to not just passively wait for entropy
to happen, but to start actively collecting it if it is missing.  This
is not necessarily always possible, but if the architecture has a CPU
cycle counter, there is a fair amount of noise in the exact timings of
reasonably complex loads.

We may end up tweaking the load and the entropy estimates, but this
should be at least a reasonable starting point.

As part of this, we also revert the revert of the ext4 IO pattern
improvement that ended up triggering the reported lack of external
entropy.

* getrandom() active entropy waiting:
  Revert "Revert "ext4: make __ext4_get_inode_loc plug""
  random: try to actively add entropy rather than passively wait for it

This reverts commit 72dbcf72.

Instead of waiting forever for entropy that may just not happen, we now
try to actively generate entropy when required, and are thus hopefully
avoiding the problem that caused the nice ext4 IO pattern fix to be
reverted.

So revert the revert.

Cc: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For 5.3 we had to revert a nice ext4 IO pattern improvement, because it
caused a bootup regression due to lack of entropy at bootup together
with arguably broken user space that was asking for secure random
numbers when it really didn't need to.

See commit 72dbcf72 (Revert "ext4: make __ext4_get_inode_loc plug").

This aims to solve the issue by actively generating entropy noise using
the CPU cycle counter when waiting for the random number generator to
initialize.  This only works when you have a high-frequency time stamp
counter available, but that's the case on all modern x86 CPU's, and on
most other modern CPU's too.

What we do is to generate jitter entropy from the CPU cycle counter
under a somewhat complex load: calling the scheduler while also
guaranteeing a certain amount of timing noise by also triggering a
timer.

I'm sure we can tweak this, and that people will want to look at other
alternatives, but there's been a number of papers written on jitter
entropy, and this should really be fairly conservative by crediting one
bit of entropy for every timer-induced jump in the cycle counter.  Not
because the timer itself would be all that unpredictable, but because
the interaction between the timer and the loop is going to be.

Even if (and perhaps particularly if) the timer actually happens on
another CPU, the cacheline interaction between the loop that reads the
cycle counter and the timer itself firing is going to add perturbations
to the cycle counter values that get mixed into the entropy pool.

As Thomas pointed out, with a modern out-of-order CPU, even quite simple
loops show a fair amount of hard-to-predict timing variability even in
the absense of external interrupts.  But this tries to take that further
by actually having a fairly complex interaction.

This is not going to solve the entropy issue for architectures that have
no CPU cycle counter, but it's not clear how (and if) that is solvable,
and the hardware in question is largely starting to be irrelevant.  And
by doing this we can at least avoid some of the even more contentious
approaches (like making the entropy waiting time out in order to avoid
the possibly unbounded waiting).

Cc: Ahmed Darwish <darwish.07@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Nicholas Mc Guire <hofrat@opentech.at>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'fixes-5.4-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into arm/fixes

Fixes for omap variants

Few fixes for ti-sysc interconnect target module driver for no-idle
quirks that caused nfsroot to fail on some dra7 boards.

And let's fixes to get LCD working again for logicpd board that got
broken a while back with removal of panel-dpi driver. We need to now
use generic CONFIG_DRM_PANEL_SIMPLE instead.

* tag 'fixes-5.4-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle()
  ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
  ARM: dts: am3517-evm: Fix missing video
  ARM: dts: logicpd-torpedo-baseboard: Fix missing video
  ARM: omap2plus_defconfig: Fix missing video
  bus: ti-sysc: Fix handling of invalid clocks
  bus: ti-sysc: Fix clock handling for no-idle quirks

Link: https://lore.kernel.org/r/pull-1568819401-72461@atomide.comSigned-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'scmi-fixes-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/fixes

ARM SCMI fixes for v5.4

Couple of fixes: one in scmi reset driver initialising missed scmi handle
and an other in scmi reset API implementation fixing the assignment of
reset state

* tag 'scmi-fixes-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
  reset: reset-scmi: add missing handle initialisation
  firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset

Link: https://lore.kernel.org/r/20190918142139.GA4370@bogusSigned-off-by: Olof Johansson <olof@lixom.net>

More libnvdimm updates from Dan Williams:

 - Complete the reworks to interoperate with powerpc dynamic huge page
   sizes

 - Fix a crash due to missed accounting for the powerpc 'struct
   page'-memmap mapping granularity

 - Fix badblock initialization for volatile (DRAM emulated) pmem ranges

 - Stop triggering request_key() notifications to userspace when
   NVDIMM-security is disabled / not present

 - Miscellaneous small fixups

* tag 'libnvdimm-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm/region: Enable MAP_SYNC for volatile regions
  libnvdimm: prevent nvdimm from requesting key when security is disabled
  libnvdimm/region: Initialize bad block for volatile namespaces
  libnvdimm/nfit_test: Fix acpi_handle redefinition
  libnvdimm/altmap: Track namespace boundaries in altmap
  libnvdimm: Fix endian conversion issues 
  libnvdimm/dax: Pick the right alignment default when creating dax devices
  powerpc/book3s64: Export has_transparent_hugepage() related functions.

Pull thermal SoC updates from Eduardo Valentin:
 "This is a really small pull in the midst of a lot of pending patches.

  We are in the middle of restructuring how we are maintaining the
  thermal subsystem, as per discussion in our last LPC. For now, I am
  sending just some changes that were pending in my tree. Looking
  forward to get a more streamlined process in the next merge window"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: db8500: Rewrite to be a pure OF sensor
  thermal: db8500: Use dev helper variable
  thermal: db8500: Finalize device tree conversion
  thermal: thermal_mmio: remove some dead code

Pull  more i2c updates from Wolfram Sang:

 - make Lenovo Yoga C630 boot now that the dependencies are merged

 - restore BlockProcessCall for i801, accidently removed in this merge
   window

 - a bugfix for the riic driver

 - an improvement to the slave-eeprom driver which should have been in
   the first pull request but sadly got lost in the process

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: slave-eeprom: Add read only mode
  i2c: i801: Bring back Block Process Call support for certain platforms
  i2c: riic: Clear NACK in tend isr
  i2c: qcom-geni: Disable DMA processing on the Lenovo Yoga C630

Pull iommu fixes from Joerg Roedel:
 "A couple of fixes for the AMD IOMMU driver have piled up:

   - Some fixes for the reworked IO page-table which caused memory leaks
     or did not allow to downgrade mappings under some conditions.

   - Locking fixes to fix a couple of possible races around accessing
     'struct protection_domain'. The races got introduced when the
     dma-ops path became lock-less in the fast-path"

* tag 'iommu-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Lock code paths traversing protection_domain->dev_list
  iommu/amd: Lock dev_data in attach/detach code paths
  iommu/amd: Check for busy devices earlier in attach_device()
  iommu/amd: Take domain->lock for complete attach/detach path
  iommu/amd: Remove amd_iommu_devtable_lock
  iommu/amd: Remove domain->updated
  iommu/amd: Wait for completion of IOTLB flush in attach_device
  iommu/amd: Unmap all L7 PTEs when downgrading page-sizes
  iommu/amd: Introduce first_pte_l7() helper
  iommu/amd: Fix downgrading default page-sizes in alloc_pte()
  iommu/amd: Fix pages leak in free_pagetable()

The role of the contact list provided by the disclosing party and how it
affects the disclosure process and the ability to include experts into
the development process is not really well explained.

Neither is it entirely clear when the disclosing party will be informed
about the fact that a developer who is not covered by an employer NDA needs
to be brought in and disclosed.

Explain the role of the contact list and the information policy along with
an eventual conflict resolution better.
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.1909251028390.10825@nanos.tec.linutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull networking fixes from David Miller:

 1) Sanity check URB networking device parameters to avoid divide by
    zero, from Oliver Neukum.

 2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
    don't work properly. Longer term this needs a better fix tho. From
    Vijay Khemka.

 3) Small fixes to selftests (use ping when ping6 is not present, etc.)
    from David Ahern.

 4) Bring back rt_uses_gateway member of struct rtable, it's semantics
    were not well understood and trying to remove it broke things. From
    David Ahern.

 5) Move usbnet snaity checking, ignore endpoints with invalid
    wMaxPacketSize. From Bjørn Mork.

 6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.

 7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
    Alex Vesker, and Yevgeny Kliteynik

 8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.

 9) Fix crash when removing sch_cbs entry while offloading is enabled,
    from Vinicius Costa Gomes.

10) Signedness bug fixes, generally in looking at the result given by
    of_get_phy_mode() and friends. From Dan Crapenter.

11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.

12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.

13) Fix quantization code in tcp_bbr, from Kevin Yang.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
  net: tap: clean up an indentation issue
  nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
  tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
  sk_buff: drop all skb extensions on free and skb scrubbing
  tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
  mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
  Documentation: Clarify trap's description
  mlxsw: spectrum: Clear VLAN filters during port initialization
  net: ena: clean up indentation issue
  NFC: st95hf: clean up indentation issue
  net: phy: micrel: add Asym Pause workaround for KSZ9021
  net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
  ptp: correctly disable flags on old ioctls
  lib: dimlib: fix help text typos
  net: dsa: microchip: Always set regmap stride to 1
  nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
  nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
  net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
  vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
  net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
  ...

Merge hugepage allocation updates from David Rientjes:
 "We (mostly Linus, Andrea, and myself) have been discussing offlist how
  to implement a sane default allocation strategy for hugepages on NUMA
  platforms.

  With these reverts in place, the page allocator will happily allocate
  a remote hugepage immediately rather than try to make a local hugepage
  available. This incurs a substantial performance degradation when
  memory compaction would have otherwise made a local hugepage
  available.

  This series reverts those reverts and attempts to propose a more sane
  default allocation strategy specifically for hugepages. Andrea
  acknowledges this is likely to fix the swap storms that he originally
  reported that resulted in the patches that removed __GFP_THISNODE from
  hugepage allocations.

  The immediate goal is to return 5.3 to the behavior the kernel has
  implemented over the past several years so that remote hugepages are
  not immediately allocated when local hugepages could have been made
  available because the increased access latency is untenable.

  The next goal is to introduce a sane default allocation strategy for
  hugepages allocations in general regardless of the configuration of
  the system so that we prevent thrashing of local memory when
  compaction is unlikely to succeed and can prefer remote hugepages over
  remote native pages when the local node is low on memory."

Note on timing: this reverts the hugepage VM behavior changes that got
introduced fairly late in the 5.3 cycle, and that fixed a huge
performance regression for certain loads that had been around since
4.18.

Andrea had this note:

 "The regression of 4.18 was that it was taking hours to start a VM
  where 3.10 was only taking a few seconds, I reported all the details
  on lkml when it was finally tracked down in August 2018.

     https://lore.kernel.org/linux-mm/20180820032640.9896-2-aarcange@redhat.com/

  __GFP_THISNODE in MADV_HUGEPAGE made the above enterprise vfio
  workload degrade like in the "current upstream" above. And it still
  would have been that bad as above until 5.3-rc5"

where the bad behavior ends up happening as you fill up a local node,
and without that change, you'd get into the nasty swap storm behavior
due to compaction working overtime to make room for more memory on the
nodes.

As a result 5.3 got the two performance fix reverts in rc5.

However, David Rientjes then noted that those performance fixes in turn
regressed performance for other loads - although not quite to the same
degree.  He suggested reverting the reverts and instead replacing them
with two small changes to how hugepage allocations are done (patch
descriptions rephrased by me):

 - "avoid expensive reclaim when compaction may not succeed": just admit
   that the allocation failed when you're trying to allocate a huge-page
   and compaction wasn't successful.

 - "allow hugepage fallback to remote nodes when madvised": when that
   node-local huge-page allocation failed, retry without forcing the
   local node.

but by then I judged it too late to replace the fixes for a 5.3 release.
So 5.3 was released with behavior that harked back to the pre-4.18 logic.

But now we're in the merge window for 5.4, and we can see if this
alternate model fixes not just the horrendous swap storm behavior, but
also restores the performance regression that the late reverts caused.

Fingers crossed.

* emailed patches from David Rientjes <rientjes@google.com>:
  mm, page_alloc: allow hugepage fallback to remote nodes when madvised
  mm, page_alloc: avoid expensive reclaim when compaction may not succeed
  Revert "Revert "Revert "mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask""
  Revert "Revert "mm, thp: restore node-local hugepage allocations""

The "same probe" selftest that tests that adding the same probe fails
doesn't add the same probe and passes, which fails the test.

Fixes: b78b94b8 ("selftests/ftrace: Update kprobe event error testcase")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

To improve the readability of raw slab trace points, print the call_site ip
using '%pS'. Then we can grep events with function names.

[002] ....   808.188897: kmem_cache_free: call_site=putname+0x47/0x50 ptr=00000000cef40c80
[002] ....   808.188898: kfree: call_site=security_cred_free+0x42/0x50 ptr=0000000062400820
[002] ....   808.188904: kmem_cache_free: call_site=put_cred_rcu+0x88/0xa0 ptr=0000000058d74ef8
[002] ....   808.188913: kmem_cache_alloc: call_site=prepare_creds+0x26/0x100 ptr=0000000058d74ef8 bytes_req=168 bytes_alloc=576 gfp_flags=GFP_KERNEL
[002] ....   808.188917: kmalloc: call_site=security_prepare_creds+0x77/0xa0 ptr=0000000062400820 bytes_req=8 bytes_alloc=336 gfp_flags=GFP_KERNEL|__GFP_ZERO
[002] ....   808.188920: kmem_cache_alloc: call_site=getname_flags+0x4f/0x1e0 ptr=00000000cef40c80 bytes_req=4096 bytes_alloc=4480 gfp_flags=GFP_KERNEL
[002] ....   808.188925: kmem_cache_free: call_site=putname+0x47/0x50 ptr=00000000cef40c80
[002] ....   808.188926: kfree: call_site=security_cred_free+0x42/0x50 ptr=0000000062400820
[002] ....   808.188931: kmem_cache_free: call_site=put_cred_rcu+0x88/0xa0 ptr=0000000058d74ef8

Link: http://lkml.kernel.org/r/20190914103215.23301-1-changbin.du@gmail.comSigned-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

In predicate_parse, there is an error path that is not going to
out_free instead it returns directly which leads to a memory leak.

Link: http://lkml.kernel.org/r/20190920225800.3870-1-navid.emamdoost@gmail.comSigned-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

After r372664 in clang, the IF_ASSIGN macro causes a couple hundred
warnings along the lines of:

kernel/trace/trace_output.c:1331:2: warning: converting the enum
constant to a boolean [-Wint-in-bool-context]
kernel/trace/trace.h:409:3: note: expanded from macro
'trace_assign_type'
                IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,
                ^
kernel/trace/trace.h:371:14: note: expanded from macro 'IF_ASSIGN'
                WARN_ON(id && (entry)->type != id);     \
                           ^
264 warnings generated.

This warning can catch issues with constructs like:

    if (state == A || B)

where the developer really meant:

    if (state == A || state == B)

This is currently the only occurrence of the warning in the kernel
tree across defconfig, allyesconfig, allmodconfig for arm32, arm64,
and x86_64. Add the implicit '!= 0' to the WARN_ON statement to fix
the warnings and find potential issues in the future.

Link: https://github.com/llvm/llvm-project/commit/28b38c277a2941e9e891b2db30652cfd962f070b
Link: https://github.com/ClangBuiltLinux/linux/issues/686
Link: http://lkml.kernel.org/r/20190926162258.466321-1-natechancellor@gmail.comReviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Steven reported that a test triggered:

==================================================================
 BUG: KASAN: slab-out-of-bounds in trace_kprobe_create+0xa9e/0xe40
 Read of size 8 at addr ffff8880c4f25a48 by task ftracetest/4798

 CPU: 2 PID: 4798 Comm: ftracetest Not tainted 5.3.0-rc6-test+ #30
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 Call Trace:
  dump_stack+0x7c/0xc0
  ? trace_kprobe_create+0xa9e/0xe40
  print_address_description+0x6c/0x332
  ? trace_kprobe_create+0xa9e/0xe40
  ? trace_kprobe_create+0xa9e/0xe40
  __kasan_report.cold.6+0x1a/0x3b
  ? trace_kprobe_create+0xa9e/0xe40
  kasan_report+0xe/0x12
  trace_kprobe_create+0xa9e/0xe40
  ? print_kprobe_event+0x280/0x280
  ? match_held_lock+0x1b/0x240
  ? find_held_lock+0xac/0xd0
  ? fs_reclaim_release.part.112+0x5/0x20
  ? lock_downgrade+0x350/0x350
  ? kasan_unpoison_shadow+0x30/0x40
  ? __kasan_kmalloc.constprop.6+0xc1/0xd0
  ? trace_kprobe_create+0xe40/0xe40
  ? trace_kprobe_create+0xe40/0xe40
  create_or_delete_trace_kprobe+0x2e/0x60
  trace_run_command+0xc3/0xe0
  ? trace_panic_handler+0x20/0x20
  ? kasan_unpoison_shadow+0x30/0x40
  trace_parse_run_command+0xdc/0x163
  vfs_write+0xe1/0x240
  ksys_write+0xba/0x150
  ? __ia32_sys_read+0x50/0x50
  ? tracer_hardirqs_on+0x61/0x180
  ? trace_hardirqs_off_caller+0x43/0x110
  ? mark_held_locks+0x29/0xa0
  ? do_syscall_64+0x14/0x260
  do_syscall_64+0x68/0x260

Fix to check the difference of nr_args before adding probe
on existing probes. This also may set the error log index
bigger than the number of command parameters. In that case
it sets the error position is next to the last parameter.

Link: http://lkml.kernel.org/r/156966474783.3478.13217501608215769150.stgit@devnote2

Fixes: ca89bc07 ("tracing/kprobe: Add multi-probe per event support")
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

For systems configured to always try hard to allocate transparent
hugepages (thp defrag setting of "always") or for memory that has been
explicitly madvised to MADV_HUGEPAGE, it is often better to fallback to
remote memory to allocate the hugepage if the local allocation fails
first.

The point is to allow the initial call to __alloc_pages_node() to attempt
to defragment local memory to make a hugepage available, if possible,
rather than immediately fallback to remote memory.  Local hugepages will
always have a better access latency than remote (huge)pages, so an attempt
to make a hugepage available locally is always preferred.

If memory compaction cannot be successful locally, however, it is likely
better to fallback to remote memory.  This could take on two forms: either
allow immediate fallback to remote memory or do per-zone watermark checks.
It would be possible to fallback only when per-zone watermarks fail for
order-0 memory, since that would require local reclaim for all subsequent
faults so remote huge allocation is likely better than thrashing the local
zone for large workloads.

In this case, it is assumed that because the system is configured to try
hard to allocate hugepages or the vma is advised to explicitly want to try
hard for hugepages that remote allocation is better when local allocation
and memory compaction have both failed.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>