um: remove copy_from_kernel_nofault_allowed

There is no need to override the default version of this function
anymore as UML now has proper _nofault memory access functions.

Doing this also fixes t

um: remove copy_from_kernel_nofault_allowed

There is no need to override the default version of this function
anymore as UML now has proper _nofault memory access functions.

Doing this also fixes the fact that the implementation was incorrect as
using mincore() will incorrectly flag pages as inaccessible if they were
swapped out by the host.

Fixes: f75b1b1bedfb ("um: Implement probe_kernel_read()")
Signed-off-by: Benjamin Berg <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Johannes Berg <[email protected]>

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kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention withou

kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

$(obj) - directory in the object tree
$(src) - directory in the source tree (changed by this commit)
$(objtree) - the top of the kernel object tree
$(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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kbuild: remove --include-dir MAKEFLAG from top Makefile

I added $(srctree)/ to some included Makefiles in the following commits:

- 3204a7fb98a3 ("kbuild: prefix $(srctree)/ to some included Makefi

kbuild: remove --include-dir MAKEFLAG from top Makefile

I added $(srctree)/ to some included Makefiles in the following commits:

- 3204a7fb98a3 ("kbuild: prefix $(srctree)/ to some included Makefiles")
- d82856395505 ("kbuild: do not require sub-make for separate output tree builds")

They were a preparation for removing --include-dir flag.

I have never thought --include-dir useful. Rather, it _is_ harmful.

For example, run the following commands:

$ make -s ARCH=x86 mrproper defconfig
$ make ARCH=arm O=foo dtbs
make[1]: Entering directory '/tmp/linux/foo'
HOSTCC scripts/basic/fixdep
Error: kernelrelease not valid - run 'make prepare' to update it
UPD include/config/kernel.release
make[1]: Leaving directory '/tmp/linux/foo'

The first command configures the source tree for x86. The next command
tries to build ARM device trees in the separate foo/ directory - this
must stop because the directory foo/ has not been configured yet.

However, due to --include-dir=$(abs_srctree), the top Makefile includes
the wrong include/config/auto.conf from the source tree and continues
building. Kbuild traverses the directory tree, but of course it does
not work correctly. The Error message is also pointless - 'make prepare'
does not help at all for fixing the issue.

This commit fixes more arch Makefile, and finally removes --include-dir
from the top Makefile.

There are more breakages under drivers/, but I do not volunteer to fix
them all. I just moved --include-dir to drivers/Makefile.

With this commit, the second command will stop with a sensible message.

$ make -s ARCH=x86 mrproper defconfig
$ make ARCH=arm O=foo dtbs
make[1]: Entering directory '/tmp/linux/foo'
SYNC include/config/auto.conf.cmd
***
*** The source tree is not clean, please run 'make ARCH=arm mrproper'
*** in /tmp/linux
***
make[2]: *** [../Makefile:646: outputmakefile] Error 1
/tmp/linux/Makefile:770: include/config/auto.conf.cmd: No such file or directory
make[1]: *** [/tmp/linux/Makefile:793: include/config/auto.conf.cmd] Error 2
make[1]: Leaving directory '/tmp/linux/foo'
make: *** [Makefile:226: __sub-make] Error 2

Signed-off-by: Masahiro Yamada <[email protected]>

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um: Add devicetree support

Add a dtb=<filename> option to boot UML with a devicetree blob. This
can be used for testing driver code using UML.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch

um: Add devicetree support

Add a dtb=<filename> option to boot UML with a devicetree blob. This
can be used for testing driver code using UML.

Signed-off-by: Vincent Whitchurch <[email protected]>
[rw: Add dependency on CONFIG_OF]
Signed-off-by: Richard Weinberger <[email protected]>

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um: Extract load file helper from initrd.c

The file loading support in initrd.c can be re-used for
loading devicetrees. Move it out of initrd.c.

Signed-off-by: Vincent Whitchurch <vincent.whitchur

um: Extract load file helper from initrd.c

The file loading support in initrd.c can be re-used for
loading devicetrees. Move it out of initrd.c.

Signed-off-by: Vincent Whitchurch <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: move amd64 variant of mmap(2) to arch/x86/um/syscalls_64.c

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

um: Add support for host CPU flags and alignment

1. Reflect host cpu flags into the UML instance so they can
be used to select the correct implementations for xor, crypto, etc.

2. Reflect host cach

um: Add support for host CPU flags and alignment

1. Reflect host cpu flags into the UML instance so they can
be used to select the correct implementations for xor, crypto, etc.

2. Reflect host cache alignment into UML instance. This is
important when running 32 bit on a 64 bit host as 32 bit by
default aligns to 32 while the actual alignment should be 64.
Ditto for some Xeons which align at 128.

Signed-off-by: Anton Ivanov <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: add PCI over virtio emulation driver

To support testing of PCI/PCIe drivers in UML, add a PCI bus
support driver. This driver uses virtio, which in UML is really
just vhost-user, to talk to devi

um: add PCI over virtio emulation driver

To support testing of PCI/PCIe drivers in UML, add a PCI bus
support driver. This driver uses virtio, which in UML is really
just vhost-user, to talk to devices, and adds the devices to
the virtual PCI bus in the system.

Since virtio already allows DMA/bus mastering this really isn't
all that hard, of course we need the logic_iomem infrastructure
that was added by a previous patch.

The protocol to talk to the device is has a few fairly simple
messages for reading to/writing from config and IO spaces, and
messages for the device to send the various interrupts (INT#,
MSI/MSI-X and while suspended PME#).

Note that currently no offical virtio device ID is assigned for
this protocol, as a consequence this patch requires defining it
in the Kconfig, with a default that makes the driver refuse to
work at all.

Finally, in order to add support for MSI/MSI-X interrupts, some
small changes are needed in the UML IRQ code, it needs to have
more interrupts, changing NR_IRQS from 64 to 128 if this driver
is enabled, but not actually use them for anything so that the
generic IRQ domain/MSI infrastructure can allocate IRQ numbers.

Signed-off-by: Johannes Berg <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: Disable CONFIG_GCOV with MODULES

CONFIG_GCOV doesn't work with modules, and for various reasons
it cannot work, see also
https://lore.kernel.org/r/d36ea54d8c0a8dd706826ba844a6f27691f45d55.camel@

um: Disable CONFIG_GCOV with MODULES

CONFIG_GCOV doesn't work with modules, and for various reasons
it cannot work, see also
https://lore.kernel.org/r/[email protected]

Make CONFIG_GCOV depend on !MODULES to avoid anyone
running into issues there. This also means we need
not export the gcov symbols.

Signed-off-by: Johannes Berg <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: Add SPDX headers to files in arch/um/kernel/

Convert files to use SPDX header. All files are licensed under the
GPLv2.

Signed-off-by: Alex Dewar <[email protected]>
Signed-off-by: Richard We

um: Add SPDX headers to files in arch/um/kernel/

Convert files to use SPDX header. All files are licensed under the
GPLv2.

Signed-off-by: Alex Dewar <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: Remove meaningless clearing of clean-files

Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

um: Support kcov

This adds support for kcov to UML.

There is a small problem where UML will randomly segfault during boot;
this is because current_thread_info() occasionally returns an invalid
(non

um: Support kcov

This adds support for kcov to UML.

There is a small problem where UML will randomly segfault during boot;
this is because current_thread_info() occasionally returns an invalid
(non-NULL) pointer and we try to dereference it in
__sanitizer_cov_trace_pc(). I consider this a bug in UML itself and this
patch merely exposes it.

[v2: disable instrumentation in UML-specific code]

Cc: Quentin Casasnovas <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Thomas Meyer <[email protected]>
Cc: user-mode-linux-devel <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Signed-off-by: Vegard Nossum <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: add a kmsg_dumper

Add a kmsg_dumper, that dumps the kmsg buffer to stdout, when no console
is available. This an enables the printing of early panic() calls
triggered in uml_postsetup().
When a

um: add a kmsg_dumper

Add a kmsg_dumper, that dumps the kmsg buffer to stdout, when no console
is available. This an enables the printing of early panic() calls
triggered in uml_postsetup().
When a panic() call happens so early in the UML kernel no
earlyprintk/console is available yet, but with a kmsg_dumper in place
the kernel message buffer will be outputted to the user, to give a
better hint, of what the failure was.

Signed-off-by: Thomas Meyer <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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um: Remove broken SMP support

At times where UML used the TT mode to operate it had
kind of SMP support. It never got finished nor was
stable.
Let's rip out that cruft and stop confusing developers

um: Remove broken SMP support

At times where UML used the TT mode to operate it had
kind of SMP support. It never got finished nor was
stable.
Let's rip out that cruft and stop confusing developers
which do tree-wide SMP cleanups.

If someone wants SMP support UML it has do be done from scratch.

Signed-off-by: Richard Weinberger <[email protected]>

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um: Add support for CONFIG_STACKTRACE

Add stacktrace support for User Mode Linux

Signed-off-by: Daniel Walter <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

um: Implement probe_kernel_read()

UML needs it's own probe_kernel_read() to handle kernel
mode faults correctly.
The implementation uses mincore() on the host side to detect
whether a page is owned

um: Implement probe_kernel_read()

UML needs it's own probe_kernel_read() to handle kernel
mode faults correctly.
The implementation uses mincore() on the host side to detect
whether a page is owned by the UML kernel process.

This fixes also a possible crash when sysrq-t is used.
Starting with 3.10 sysrq-t calls probe_kernel_read() to
read details from the kernel workers. As kernel worker are
completely async pointers may turn NULL while reading them.

Cc: <[email protected]>
Cc: <[email protected]>
Cc: <[email protected]> # 3.10.x
Signed-off-by: Richard Weinberger <[email protected]>

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um: Use generic init_task

Same code. Use the generic version.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Richard Weinberger <[email protected]>
Link: http://lkml.kernel.org/r/201205

um: Use generic init_task

Same code. Use the generic version.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Richard Weinberger <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]

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um: fix linker script generation

while we can't just use -U$(SUBARCH), we still need to kill idiotic define
(implicit -Di386=1), both for SUBARCH=i386 and SUBARCH=x86/CONFIG_64BIT=n
builds.

Signed-

um: fix linker script generation

while we can't just use -U$(SUBARCH), we still need to kill idiotic define
(implicit -Di386=1), both for SUBARCH=i386 and SUBARCH=x86/CONFIG_64BIT=n
builds.

Signed-off-by: Al Viro <[email protected]>

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um: most of the SUBARCH uses can be killed

Signed-off-by: Al Viro <[email protected]>
[[email protected]: Re-export SUBARCH in arch/um/Makefile]
Signed-off-by: Richard Weinberger <[email protected]>

um: kill dead code around uaccess

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

um: add earlyprintk support

User Mode Linux can also benefit from earlyprintk. UML's earlyprintk
writes kernel messages directly to stdout.

Signed-off-by: Richard Weinberger <[email protected]>
Signe

um: add earlyprintk support

User Mode Linux can also benefit from earlyprintk. UML's earlyprintk
writes kernel messages directly to stdout.

Signed-off-by: Richard Weinberger <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0

Albin Tonnerre <[email protected]> reported:

Bash 4 filters out variables which contain a dot in them.
T

arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0

Albin Tonnerre <[email protected]> reported:

Bash 4 filters out variables which contain a dot in them.
This happends to be the case of CPPFLAGS_vmlinux.lds.
This is rather unfortunate, as it now causes
build failures when using SHELL=/bin/bash to compile,
or when bash happens to be used by make (eg when it's /bin/sh)

Remove the common definition of CPPFLAGS_vmlinux.lds by
pushing relevant stuff to either Makefile.build or the
arch specific kernel/Makefile where we build the linker script.

This is also nice cleanup as we move the information out where
it is used.

Notes for the different architectures touched:

arm - we use an already exported symbol
cris - we use a config symbol aleady available
[Not build tested]
mips - the jiffies complexity has moved to vmlinux.lds.S where we need it.
Added a few variables to CPPFLAGS - they are only used by
the linker script.
[Not build tested]
powerpc - removed assignment that is not needed
[not build tested]
sparc - simplified it using $(BITS)
um - introduced a few new exported variables to deal with this
xtensa - added options to CPP invocation
[not build tested]

Cc: Albin Tonnerre <[email protected]>
Cc: Russell King <[email protected]>
Cc: Mikael Starvik <[email protected]>
Cc: Jesper Nilsson <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jeff Dike <[email protected]>
Cc: Chris Zankel <[email protected]>
Signed-off-by: Sam Ravnborg <[email protected]>

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uml: don't use a too long string literal

uml uses a concatenated string literal to store the contents of .config,
but .config file content is varaible, it can be very long.

Use an array of string l

uml: don't use a too long string literal

uml uses a concatenated string literal to store the contents of .config,
but .config file content is varaible, it can be very long.

Use an array of string literals instead.

Signed-off-by: WANG Cong <[email protected]>
Cc: Jeff Dike <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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uml: style fixes pass 1

Formatting changes in the files which have been changed in the
tt-removal patchset so far. These include:
copyright updates
header file trimming
style fixes
adding sever

uml: style fixes pass 1

Formatting changes in the files which have been changed in the
tt-removal patchset so far. These include:
copyright updates
header file trimming
style fixes
adding severity to printks
indenting Kconfig help according to the predominant kernel style

These changes should be entirely non-functional.

Signed-off-by: Jeff Dike <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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uml: throw out CONFIG_MODE_TT

This patchset throws out tt mode, which has been non-functional for a while.

This is done in phases, interspersed with code cleanups on the affected files.

The remova

uml: throw out CONFIG_MODE_TT

This patchset throws out tt mode, which has been non-functional for a while.

This is done in phases, interspersed with code cleanups on the affected files.

The removal is done as follows:
remove all code, config options, and files which depend on
CONFIG_MODE_TT
get rid of the CHOOSE_MODE macro, which decided whether to
call tt-mode or skas-mode code, and replace invocations with their
skas portions
replace all now-trivial procedures with their skas equivalents

There are now a bunch of now-redundant pieces of data structures, including
mode-specific pieces of the thread structure, pt_regs, and mm_context. These
are all replaced with their skas-specific contents.

As part of the ongoing style compliance project, I made a style pass over all
files that were changed. There are three such patches, one for each phase,
covering the files affected by that phase but no later ones.

I noticed that we weren't freeing the LDT state associated with a process when
it exited, so that's fixed in one of the later patches.

The last patch is a tidying patch which I've had for a while, but which caused
inexplicable crashes under tt mode. Since that is no longer a problem, this
can now go in.

This patch:

Start getting rid of tt mode support.

This patch throws out CONFIG_MODE_TT and all config options, code, and files
which depend on it.

CONFIG_MODE_SKAS is gone and everything that depends on it is included
unconditionally.

The few changed lines are in re-written Kconfig help, lines which needed
something skas-related removed from them, and a few more which weren't
strictly deletions.

Signed-off-by: Jeff Dike <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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