x86: stop playing stack games in profile_pc()

The 'profile_pc()' function is used for timer-based profiling, which
isn't really all that relevant any more to begin with, but it also ends
up making a

x86: stop playing stack games in profile_pc()

The 'profile_pc()' function is used for timer-based profiling, which
isn't really all that relevant any more to begin with, but it also ends
up making assumptions based on the stack layout that aren't necessarily
valid.

Basically, the code tries to account the time spent in spinlocks to the
caller rather than the spinlock, and while I support that as a concept,
it's not worth the code complexity or the KASAN warnings when no serious
profiling is done using timers anyway these days.

And the code really does depend on stack layout that is only true in the
simplest of cases. We've lost the comment at some point (I think when
the 32-bit and 64-bit code was unified), but it used to say:

Assume the lock function has either no stack frame or a copy
of eflags from PUSHF.

which explains why it just blindly loads a word or two straight off the
stack pointer and then takes a minimal look at the values to just check
if they might be eflags or the return pc:

Eflags always has bits 22 and up cleared unlike kernel addresses

but that basic stack layout assumption assumes that there isn't any lock
debugging etc going on that would complicate the code and cause a stack
frame.

It causes KASAN unhappiness reported for years by syzkaller [1] and
others [2].

With no real practical reason for this any more, just remove the code.

Just for historical interest, here's some background commits relating to
this code from 2006:

0cb91a229364 ("i386: Account spinlocks to the caller during profiling for !FP kernels")
31679f38d886 ("Simplify profile_pc on x86-64")

and a code unification from 2009:

ef4512882dbe ("x86: time_32/64.c unify profile_pc")

but the basics of this thing actually goes back to before the git tree.

Link: https://syzkaller.appspot.com/bug?extid=84fe685c02cd112a2ac3 [1]
Link: https://lore.kernel.org/all/CAK55_s7Xyq=nh97=K=G1sxueOFrJDAvPOJAL4TPTCAYvmxO9_A@mail.gmail.com/ [2]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

x86_64: Fix jiffies ODR violation

'jiffies' and 'jiffies_64' are meant to alias (two different symbols that
share the same address). Most architectures make the symbols alias to the
same address vi

x86_64: Fix jiffies ODR violation

'jiffies' and 'jiffies_64' are meant to alias (two different symbols that
share the same address). Most architectures make the symbols alias to the
same address via a linker script assignment in their
arch/<arch>/kernel/vmlinux.lds.S:

jiffies = jiffies_64;

which is effectively a definition of jiffies.

jiffies and jiffies_64 are both forward declared for all architectures in
include/linux/jiffies.h. jiffies_64 is defined in kernel/time/timer.c.

x86_64 was peculiar in that it wasn't doing the above linker script
assignment, but rather was:
1. defining jiffies in arch/x86/kernel/time.c instead via the linker script.
2. overriding the symbol jiffies_64 from kernel/time/timer.c in
arch/x86/kernel/vmlinux.lds.s via 'jiffies_64 = jiffies;'.

As Fangrui notes:

In LLD, symbol assignments in linker scripts override definitions in
object files. GNU ld appears to have the same behavior. It would
probably make sense for LLD to error "duplicate symbol" but GNU ld
is unlikely to adopt for compatibility reasons.

This results in an ODR violation (UB), which seems to have survived
thus far. Where it becomes harmful is when;

1. -fno-semantic-interposition is used:

As Fangrui notes:

Clang after LLVM commit 5b22bcc2b70d
("[X86][ELF] Prefer to lower MC_GlobalAddress operands to .Lfoo$local")
defaults to -fno-semantic-interposition similar semantics which help
-fpic/-fPIC code avoid GOT/PLT when the referenced symbol is defined
within the same translation unit. Unlike GCC
-fno-semantic-interposition, Clang emits such relocations referencing
local symbols for non-pic code as well.

This causes references to jiffies to refer to '.Ljiffies$local' when
jiffies is defined in the same translation unit. Likewise, references to
jiffies_64 become references to '.Ljiffies_64$local' in translation units
that define jiffies_64. Because these differ from the names used in the
linker script, they will not be rewritten to alias one another.

2. Full LTO

Full LTO effectively treats all source files as one translation
unit, causing these local references to be produced everywhere. When
the linker processes the linker script, there are no longer any
references to jiffies_64' anywhere to replace with 'jiffies'. And
thus '.Ljiffies$local' and '.Ljiffies_64$local' no longer alias
at all.

In the process of porting patches enabling Full LTO from arm64 to x86_64,
spooky bugs have been observed where the kernel appeared to boot, but init
doesn't get scheduled.

Avoid the ODR violation by matching other architectures and define jiffies
only by linker script. For -fno-semantic-interposition + Full LTO, there
is no longer a global definition of jiffies for the compiler to produce a
local symbol which the linker script won't ensure aliases to jiffies_64.

Fixes: 40747ffa5aa8 ("asmlinkage: Make jiffies visible")
Reported-by: Nathan Chancellor <[email protected]>
Reported-by: Alistair Delva <[email protected]>
Debugged-by: Nick Desaulniers <[email protected]>
Debugged-by: Sami Tolvanen <[email protected]>
Suggested-by: Fangrui Song <[email protected]>
Signed-off-by: Bob Haarman <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Sedat Dilek <[email protected]> # build+boot on
Reviewed-by: Andi Kleen <[email protected]>
Reviewed-by: Josh Poimboeuf <[email protected]>
Cc: [email protected]
Link: https://github.com/ClangBuiltLinux/linux/issues/852
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86/delay: Introduce TPAUSE delay

TPAUSE instructs the processor to enter an implementation-dependent
optimized state. The instruction execution wakes up when the time-stamp
counter reaches or excee

x86/delay: Introduce TPAUSE delay

TPAUSE instructs the processor to enter an implementation-dependent
optimized state. The instruction execution wakes up when the time-stamp
counter reaches or exceeds the implicit EDX:EAX 64-bit input value.
The instruction execution also wakes up due to the expiration of
the operating system time-limit or by an external interrupt
or exceptions such as a debug exception or a machine check exception.

TPAUSE offers a choice of two lower power states:
1. Light-weight power/performance optimized state C0.1
2. Improved power/performance optimized state C0.2

This way, it can save power with low wake-up latency in comparison to
spinloop based delay. The selection between the two is governed by the
input register.

TPAUSE is available on processors with X86_FEATURE_WAITPKG.

Co-developed-by: Fenghua Yu <[email protected]>
Signed-off-by: Fenghua Yu <[email protected]>
Signed-off-by: Kyung Min Park <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Tony Luck <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86: Replace setup_irq() by request_irq()

request_irq() is preferred over setup_irq(). The early boot setup_irq()
invocations happen either via 'init_IRQ()' or 'time_init()', while
memory allocators

x86: Replace setup_irq() by request_irq()

request_irq() is preferred over setup_irq(). The early boot setup_irq()
invocations happen either via 'init_IRQ()' or 'time_init()', while
memory allocators are ready by 'mm_init()'.

setup_irq() was required in old kernels when allocators were not ready by
the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

[ tglx: Use a local variable and get rid of the line break. Tweak the
comment a bit ]

Signed-off-by: afzal mohammed <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lkml.kernel.org/r/17f85021f6877650a5b09e0212d88323e6a30fd0.1582471508.git.afzal.mohd.ma@gmail.com

show more ...

x86/vdso: Use generic VDSO clock mode storage

Switch to the generic VDSO clock mode storage.

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@ar

x86/vdso: Use generic VDSO clock mode storage

Switch to the generic VDSO clock mode storage.

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Vincenzo Frascino <[email protected]> (VDSO parts)
Acked-by: Juergen Gross <[email protected]> (Xen parts)
Acked-by: Paolo Bonzini <[email protected]> (KVM parts)
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode

Tony reported a boot regression caused by the recent workaround for systems
which have a disabled (clock gate off) PIT.

On hi

x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode

Tony reported a boot regression caused by the recent workaround for systems
which have a disabled (clock gate off) PIT.

On his machine the kernel fails to initialize the PIT because
apic_needs_pit() does not take into account whether the local APIC
interrupt delivery mode will actually allow to setup and use the local
APIC timer. This should be easy to reproduce with acpi=off on the
command line which also disables HPET.

Due to the way the PIT/HPET and APIC setup ordering works (APIC setup can
require working PIT/HPET) the information is not available at the point
where apic_needs_pit() makes this decision.

To address this, split out the interrupt mode selection from
apic_intr_mode_init(), invoke the selection before making the decision
whether PIT is required or not, and add the missing checks into
apic_needs_pit().

Fixes: c8c4076723da ("x86/timer: Skip PIT initialization on modern chipsets")
Reported-by: Anthony Buckley <[email protected]>
Tested-by: Anthony Buckley <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Daniel Drake <[email protected]>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206125
Link: https://lore.kernel.org/r/[email protected]

show more ...

x86/timer: Skip PIT initialization on modern chipsets

Recent Intel chipsets including Skylake and ApolloLake have a special
ITSSPRC register which allows the 8254 PIT to be gated. When gated, the
8

x86/timer: Skip PIT initialization on modern chipsets

Recent Intel chipsets including Skylake and ApolloLake have a special
ITSSPRC register which allows the 8254 PIT to be gated. When gated, the
8254 registers can still be programmed as normal, but there are no IRQ0
timer interrupts.

Some products such as the Connex L1430 and exone go Rugged E11 use this
register to ship with the PIT gated by default. This causes Linux to fail
to boot:

Kernel panic - not syncing: IO-APIC + timer doesn't work! Boot with
apic=debug and send a report.

The panic happens before the framebuffer is initialized, so to the user, it
appears as an early boot hang on a black screen.

Affected products typically have a BIOS option that can be used to enable
the 8254 and make Linux work (Chipset -> South Cluster Configuration ->
Miscellaneous Configuration -> 8254 Clock Gating), however it would be best
to make Linux support the no-8254 case.

Modern sytems allow to discover the TSC and local APIC timer frequencies,
so the calibration against the PIT is not required. These systems have
always running timers and the local APIC timer works also in deep power
states.

So the setup of the PIT including the IO-APIC timer interrupt delivery
checks are a pointless exercise.

Skip the PIT setup and the IO-APIC timer interrupt checks on these systems,
which avoids the panic caused by non ticking PITs and also speeds up the
boot process.

Thanks to Daniel for providing the changelog, initial analysis of the
problem and testing against a variety of machines.

Reported-by: Daniel Drake <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Daniel Drake <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86/stackframe/32: Provide consistent pt_regs

Currently pt_regs on x86_32 has an oddity in that kernel regs
(!user_mode(regs)) are short two entries (esp/ss). This means that any
code trying to use

x86/stackframe/32: Provide consistent pt_regs

Currently pt_regs on x86_32 has an oddity in that kernel regs
(!user_mode(regs)) are short two entries (esp/ss). This means that any
code trying to use them (typically: regs->sp) needs to jump through
some unfortunate hoops.

Change the entry code to fix this up and create a full pt_regs frame.

This then simplifies various trampolines in ftrace and kprobes, the
stack unwinder, ptrace, kdump and kgdb.

Much thanks to Josh for help with the cleanups!

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Josh Poimboeuf <[email protected]>
Acked-by: Masami Hiramatsu <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

x86/time: Correct the attribute on jiffies' definition

Clang warns that the declaration of jiffies in include/linux/jiffies.h
doesn't match the definition in arch/x86/time/kernel.c:

arch/x86/kernel

x86/time: Correct the attribute on jiffies' definition

Clang warns that the declaration of jiffies in include/linux/jiffies.h
doesn't match the definition in arch/x86/time/kernel.c:

arch/x86/kernel/time.c:29:42: warning: section does not match previous declaration [-Wsection]
__visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES;
^
./include/linux/cache.h:49:4: note: expanded from macro '__cacheline_aligned'
__section__(".data..cacheline_aligned")))
^
./include/linux/jiffies.h:81:31: note: previous attribute is here
extern unsigned long volatile __cacheline_aligned_in_smp __jiffy_arch_data jiffies;
^
./arch/x86/include/asm/cache.h:20:2: note: expanded from macro '__cacheline_aligned_in_smp'
__page_aligned_data
^
./include/linux/linkage.h:39:29: note: expanded from macro '__page_aligned_data'
#define __page_aligned_data __section(.data..page_aligned) __aligned(PAGE_SIZE)
^
./include/linux/compiler_attributes.h:233:56: note: expanded from macro '__section'
#define __section(S) __attribute__((__section__(#S)))
^
1 warning generated.

The declaration was changed in commit 7c30f352c852 ("jiffies.h: declare
jiffies and jiffies_64 with ____cacheline_aligned_in_smp") but wasn't
updated here. Make them match so Clang no longer warns.

Fixes: 7c30f352c852 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp")
Signed-off-by: Nathan Chancellor <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86/vdso: Enforce 64bit clocksource

All VDSO clock sources are TSC based and use CLOCKSOURCE_MASK(64). There is
no point in masking with all FF. Get rid of it and enforce the mask in the
sanity chec

x86/vdso: Enforce 64bit clocksource

All VDSO clock sources are TSC based and use CLOCKSOURCE_MASK(64). There is
no point in masking with all FF. Get rid of it and enforce the mask in the
sanity checker.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Andy Lutomirski <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Matt Rickard <[email protected]>
Cc: Stephen Boyd <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Florian Weimer <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Vitaly Kuznetsov <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Paolo Bonzini <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Juergen Gross <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86/time: Implement clocksource_arch_init()

Runtime validate the VCLOCK_MODE in clocksource::archdata and disable
VCLOCK if invalid, which disables the VDSO but keeps the system running.

Signed-off

x86/time: Implement clocksource_arch_init()

Runtime validate the VCLOCK_MODE in clocksource::archdata and disable
VCLOCK if invalid, which disables the VDSO but keeps the system running.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Andy Lutomirski <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Matt Rickard <[email protected]>
Cc: Stephen Boyd <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Florian Weimer <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Vitaly Kuznetsov <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Paolo Bonzini <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Juergen Gross <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86: Don't include linux/irq.h from asm/hardirq.h

The next patch in this series will have to make the definition of
irq_cpustat_t available to entering_irq().

Inclusion of asm/hardirq.h into asm/ap

x86: Don't include linux/irq.h from asm/hardirq.h

The next patch in this series will have to make the definition of
irq_cpustat_t available to entering_irq().

Inclusion of asm/hardirq.h into asm/apic.h would cause circular header
dependencies like

asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/topology.h
linux/smp.h
asm/smp.h

or

linux/gfp.h
linux/mmzone.h
asm/mmzone.h
asm/mmzone_64.h
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/irqdesc.h
linux/kobject.h
linux/sysfs.h
linux/kernfs.h
linux/idr.h
linux/gfp.h

and others.

This causes compilation errors because of the header guards becoming
effective in the second inclusion: symbols/macros that had been defined
before wouldn't be available to intermediate headers in the #include chain
anymore.

A possible workaround would be to move the definition of irq_cpustat_t
into its own header and include that from both, asm/hardirq.h and
asm/apic.h.

However, this wouldn't solve the real problem, namely asm/harirq.h
unnecessarily pulling in all the linux/irq.h cruft: nothing in
asm/hardirq.h itself requires it. Also, note that there are some other
archs, like e.g. arm64, which don't have that #include in their
asm/hardirq.h.

Remove the linux/irq.h #include from x86' asm/hardirq.h.

Fix resulting compilation errors by adding appropriate #includes to *.c
files as needed.

Note that some of these *.c files could be cleaned up a bit wrt. to their
set of #includes, but that should better be done from separate patches, if
at all.

Signed-off-by: Nicolai Stange <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>

show more ...

x86/time: Unconditionally register legacy timer interrupt

Even without a PIC/PIT the legacy timer interrupt is required for HPET in
legacy replacement mode.

Signed-off-by: Peter Zijlstra (Intel) <p

x86/time: Unconditionally register legacy timer interrupt

Even without a PIC/PIT the legacy timer interrupt is required for HPET in
legacy replacement mode.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

x86/apic: Initialize interrupt mode after timer init

A cold or warm boot through BIOS sets the APIC in default interrupt
delivery mode. A dump-capture kernel will not go through a BIOS reset and
lea

x86/apic: Initialize interrupt mode after timer init

A cold or warm boot through BIOS sets the APIC in default interrupt
delivery mode. A dump-capture kernel will not go through a BIOS reset and
leave the interrupt delivery mode in the state which was active on the
crashed kernel, but the dump kernel startup code assumes default delivery
mode which can result in interrupt delivery/handling to fail.

To solve this problem, it's required to set up the final interrupt delivery
mode as soon as possible. As IOAPIC setup needs the timer initialized for
verifying the timer interrupt delivery mode, the earliest point is right
after timer setup in late_time_init().

That results in the following init order:

1) Set up the legacy timer, if applicable on the platform

2) Set up APIC/IOAPIC which includes the verification of the legacy timer
interrupt delivery.

3) TSC calibration

4) Local APIC timer setup


Signed-off-by: Dou Liyang <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

show more ...

x86/time: Make setup_default_timer_irq() static

This function isn't used outside of time.c, so let's mark it static.

Signed-off-by: Dou Liyang <[email protected]>
Cc: Linus Torvalds <torval

x86/time: Make setup_default_timer_irq() static

This function isn't used outside of time.c, so let's mark it static.

Signed-off-by: Dou Liyang <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'

user_mode_vm() and user_mode() are now the same. Change all callers
of user_mode_vm() to user_mode().

The next patch will remove t

x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'

user_mode_vm() and user_mode() are now the same. Change all callers
of user_mode_vm() to user_mode().

The next patch will remove the definition of user_mode_vm.

Signed-off-by: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brad Spengler <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org
[ Merged to a more recent kernel. ]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

x86_64/vdso: Remove jiffies from the vvar page

I think that the jiffies vvar was once used for the vgetcpu
cache. That code is long gone, so let's just make jiffies be a
normal variable.

Signed-off

x86_64/vdso: Remove jiffies from the vvar page

I think that the jiffies vvar was once used for the vgetcpu
cache. That code is long gone, so let's just make jiffies be a
normal variable.

Signed-off-by: Andy Lutomirski <[email protected]>
Link: http://lkml.kernel.org/r/fcfee6f8749af14d96373a9e2656354ad0b95499.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

x86: Fix non-PC platform kernel crash on boot due to NULL dereference

Upstream commit:

95d76acc7518d5 ("x86, irq: Count legacy IRQs by legacy_pic->nr_legacy_irqs instead of NR_IRQS_LEGACY")

remo

x86: Fix non-PC platform kernel crash on boot due to NULL dereference

Upstream commit:

95d76acc7518d5 ("x86, irq: Count legacy IRQs by legacy_pic->nr_legacy_irqs instead of NR_IRQS_LEGACY")

removed reserved interrupts for the platforms that do not have a legacy IOAPIC.

Which breaks the boot on Intel MID platforms such as Medfield:

BUG: unable to handle kernel NULL pointer dereference at 0000003a
IP: [<c107079a>] setup_irq+0xf/0x4d [ 0.000000] *pdpt = 0000000000000000 *pde = 9bbf32453167e510

The culprit is an uncoditional setting of IRQ2 which is used
as cascade IRQ on legacy platforms. It seems we have to check
if we have enough legacy IRQs reserved before we can call
setup_irq().

The fix adds such check in native_init_IRQ() and in setup_default_timer_irq().

Signed-off-by: Andy Shevchenko <[email protected]>
Reviewed-by: Jiang Liu <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Cc: David Cohen <[email protected]>
Link: http://lkml.kernel.org/r/1405931920-12871-1-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

x86: Remove deprecated IRQF_DISABLED

This patch removes the IRQF_DISABLED flag from x86 architecture
code. It's a NOOP since 2.6.35 and it will be removed one day.

Signed-off-by: Michael Opdenacker

x86: Remove deprecated IRQF_DISABLED

This patch removes the IRQF_DISABLED flag from x86 architecture
code. It's a NOOP since 2.6.35 and it will be removed one day.

Signed-off-by: Michael Opdenacker <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/1393965305-17248-1-git-send-email-michael.opdenacker@free-electrons.com
Signed-off-by: Thomas Gleixner <[email protected]>

show more ...

asmlinkage: Make jiffies visible

Jiffies is referenced by the linker script, so it has to be visible.

Handled both the generic and the x86 version.

Signed-off-by: Andi Kleen <[email protected]>
L

asmlinkage: Make jiffies visible

Jiffies is referenced by the linker script, so it has to be visible.

Handled both the generic and the x86 version.

Signed-off-by: Andi Kleen <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>

show more ...

MCA: delete all remaining traces of microchannel bus support.

Hardware with MCA bus is limited to 386 and 486 class machines
that are now 20+ years old and typically with less than 32MB
of memory.

MCA: delete all remaining traces of microchannel bus support.

Hardware with MCA bus is limited to 386 and 486 class machines
that are now 20+ years old and typically with less than 32MB
of memory. A quick search on the internet, and you see that
even the MCA hobbyist/enthusiast community has lost interest
in the early 2000 era and never really even moved ahead from
the 2.4 kernels to the 2.6 series.

This deletes anything remaining related to CONFIG_MCA from core
kernel code and from the x86 architecture. There is no point in
carrying this any further into the future.

One complication to watch for is inadvertently scooping up
stuff relating to machine check, since there is overlap in
the TLA name space (e.g. arch/x86/boot/mca.c).

Cc: Thomas Gleixner <[email protected]>
Cc: James Bottomley <[email protected]>
Cc: [email protected]
Acked-by: Ingo Molnar <[email protected]>
Acked-by: H. Peter Anvin <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>

show more ...

x86/time: Eliminate unused irq0_irqs counter

As of v2.6.38 this counter is being maintained without ever being
read.

Signed-off-by: Jan Beulich <[email protected]>
Link: http://lkml.kernel.org/r/4F

x86/time: Eliminate unused irq0_irqs counter

As of v2.6.38 this counter is being maintained without ever being
read.

Signed-off-by: Jan Beulich <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE

These files were implicitly getting EXPORT_SYMBOL via device.h
which was including module.h, but that will be fixed up shor

x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE

These files were implicitly getting EXPORT_SYMBOL via device.h
which was including module.h, but that will be fixed up shortly.

By fixing these now, we can avoid seeing things like:

arch/x86/kernel/rtc.c:29: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’
arch/x86/kernel/pci-dma.c:20: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’
arch/x86/kernel/e820.c:69: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL_GPL’

[ with input from Randy Dunlap <[email protected]> and also
from Stephen Rothwell <[email protected]> ]

Signed-off-by: Paul Gortmaker <[email protected]>

show more ...

i8253: Create linux/i8253.h and use it in all 8253 related files

Signed-off-by: Ralf Baechle <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/20110601180610.0542540

i8253: Create linux/i8253.h and use it in all 8253 related files

Signed-off-by: Ralf Baechle <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

arch/arm/mach-footbridge/isa-timer.c | 2 +-
arch/mips/cobalt/time.c | 2 +-
arch/mips/jazz/irq.c | 2 +-
arch/mips/kernel/i8253.c | 2 +-
arch/mips/mti-malta/malta-time.c | 2 +-
arch/mips/sgi-ip22/ip22-time.c | 2 +-
arch/mips/sni/time.c | 2 +-
arch/x86/kernel/apic/apic.c | 2 +-
arch/x86/kernel/apm_32.c | 2 +-
arch/x86/kernel/hpet.c | 2 +-
arch/x86/kernel/i8253.c | 2 +-
arch/x86/kernel/time.c | 2 +-
drivers/block/hd.c | 2 +-
drivers/clocksource/i8253.c | 2 +-
drivers/input/gameport/gameport.c | 2 +-
drivers/input/joystick/analog.c | 2 +-
drivers/input/misc/pcspkr.c | 2 +-
include/linux/i8253.h | 11 +++++++++++
sound/drivers/pcsp/pcsp.h | 2 +-
19 files changed, 29 insertions(+), 18 deletions(-)

show more ...