kconfig: mconf,nconf: remove unneeded '\0' termination after snprintf()
snprintf() always terminates the destination buffer with '\0' even if
the buffer is not long enough. (In this case, the last element of the
buffer becomes '\0'.)
kconfig: use /boot/config-* etc. as DEFCONFIG_LIST only for native build
When the .config file is missing, 'make config', 'make menuconfig', etc.
uses a file listed in DEFCONFIG_LIST, if found, as base configuration.
Ususally, /boot/config-$(uname -r) exists, and is used as default.
However, when you are cross-compiling the kernel, it does not make
sense to use /boot/config-* on the build host. It should default to
arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG).
UML previously did not use DEFCONFIG_LIST at all, but it should be
able to use arch/um/configs/$(KBUILD_DEFCONFIG) as a base config file.
kconfig: change sym_change_count to a boolean flag
sym_change_count has no good reason to be 'int' type.
sym_set_change_count() compares the old and new values after casting
both of them to (bool). I do not see any practical diffrence between
sym_set_change_count(1) and sym_add_change_count(1).
kconfig: nconf: fix core dump when searching in empty menu
The following code in get_mext_match():
index = (index + items_num) % items_num;
... makes the program crash when items_num is zero (that is, the menu
is empty).
A menu can be empty when all the options in it are hidden by unmet
'depends on'.
For example,
menu "This menu will be empty"
config FOO
bool "foo"
depends on BROKEN
endmenu
If you visit this menu and press a '/' key and then another key, nconf
crashes with:
Floating point exception (core dumped)
When the number of items is zero, it does not make sense to search in
the menu. In this case, current_item() returns NULL, and item_index()
ERR, but get_mext_match() does not check it.
Let's make get_mext_match() just return if the menu is empty.
While I am here, change items_num from 'int' to 'unsigned int' because
it should never become negative.
Yonghong Song [Thu, 1 Apr 2021 23:27:23 +0000 (16:27 -0700)]
kbuild: add an elfnote for whether vmlinux is built with lto
Currently, clang LTO built vmlinux won't work with pahole.
LTO introduced cross-cu dwarf tag references and broke
current pahole model which handles one cu as a time.
The solution is to merge all cu's as one pahole cu as in [1].
We would like to do this merging only if cross-cu dwarf
references happens. The LTO build mode is a pretty good
indication for that.
In earlier version of this patch ([2]), clang flag
-grecord-gcc-switches is proposed to add to compilation flags
so pahole could detect "-flto" and then merging cu's.
This will increate the binary size of 1% without LTO though.
Arnaldo suggested to use a note to indicate the vmlinux
is built with LTO. Such a cheap way to get whether the vmlinux
is built with LTO or not helps pahole but is also useful
for tracing as LTO may inline/delete/demote global functions,
promote static functions, etc.
So this patch added an elfnote with a new type LINUX_ELFNOTE_LTO_INFO.
The owner of the note is "Linux".
With gcc 8.4.1 and clang trunk, without LTO, I got
$ readelf -n vmlinux
Displaying notes found in: .notes
Owner Data size Description
...
Linux 0x00000004 func
description data: 00 00 00 00
...
With "readelf -x ".notes" vmlinux", I can verify the above "func"
with type code 0x101.
With clang thin-LTO, I got the same as above except the following:
description data: 01 00 00 00
which indicates the vmlinux is built with LTO.
Masahiro Yamada [Wed, 31 Mar 2021 13:38:10 +0000 (22:38 +0900)]
kbuild: remove CONFIG_MODULE_COMPRESS
CONFIG_MODULE_COMPRESS is only used to activate the choice for module
compression algorithm. It will be simpler to make the choice always
visible, and add CONFIG_MODULE_COMPRESS_NONE in the choice.
This is more consistent with the "Kernel compression mode" and "Built-in
initramfs compression mode" choices. CONFIG_KERNEL_UNCOMPRESSED and
CONFIG_INITRAMFS_COMPRESSION_NONE are available to choose no compression.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Masahiro Yamada [Wed, 31 Mar 2021 13:38:09 +0000 (22:38 +0900)]
kbuild: merge scripts/Makefile.modsign to scripts/Makefile.modinst
scripts/Makefile.modsign is a subset of scripts/Makefile.modinst,
and duplicates the code. Let's merge them.
By the way, you do not need to run 'make modules_sign' explicitly
because modules are signed as a part of 'make modules_install' when
CONFIG_MODULE_SIG_ALL=y. If CONFIG_MODULE_SIG_ALL=n, mod_sign_cmd is
set to 'true', so 'make modules_sign' is not functional.
In my understanding, the reason of still keeping this is to handle
corner cases like commit 64178cb62c32 ("builddeb: fix stripped module
signatures if CONFIG_DEBUG_INFO and CONFIG_MODULE_SIG_ALL are set").
Masahiro Yamada [Wed, 31 Mar 2021 13:38:08 +0000 (22:38 +0900)]
kbuild: move module strip/compression code into scripts/Makefile.modinst
Both mod_strip_cmd and mod_compress_cmd are only used in
scripts/Makefile.modinst, hence there is no good reason to define them
in the top Makefile. Move the relevant code to scripts/Makefile.modinst.
Also, show separate log messages for each of install, strip, sign, and
compress.
Masahiro Yamada [Wed, 31 Mar 2021 13:38:07 +0000 (22:38 +0900)]
kbuild: refactor scripts/Makefile.modinst
scripts/Makefile.modinst is ugly and weird in multiple ways; it
specifies real files $(modules) as phony, makes directory manipulation
needlessly too complicated.
Clean up the Makefile code, and show the full path of installed modules
in the log.
Masahiro Yamada [Wed, 31 Mar 2021 13:38:06 +0000 (22:38 +0900)]
kbuild: rename extmod-prefix to extmod_prefix
This seems to be useful in sub-make as well. As a preparation of
exporting it, rename extmod-prefix to extmod_prefix because exported
variables cannot contain hyphens.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Masahiro Yamada [Wed, 31 Mar 2021 13:38:05 +0000 (22:38 +0900)]
kbuild: check module name conflict for external modules as well
If there are multiple modules with the same name in the same external
module tree, there is ambiguity about which one will be loaded, and
very likely something odd is happening.
Masahiro Yamada [Wed, 31 Mar 2021 13:38:03 +0000 (22:38 +0900)]
kbuild: unify modules(_install) for in-tree and external modules
If you attempt to build or install modules ('make modules(_install)'
with CONFIG_MODULES disabled, you will get a clear error message, but
nothing for external module builds.
Factor out the modules and modules_install rules into the common part,
so you will get the same error message when you try to build external
modules with CONFIG_MODULES=n.
Masahiro Yamada [Thu, 25 Mar 2021 18:54:11 +0000 (03:54 +0900)]
kbuild: fix false-positive modpost warning when all symbols are trimmed
Nathan reports that the mips defconfig emits the following warning:
WARNING: modpost: Symbol info of vmlinux is missing. Unresolved symbol check will be entirely skipped.
This false-positive happens under the following combination:
- CONFIG_TRIM_UNUSED_KSYMS=y
- CONFIG_MODULES=y
- No CONFIG option is set to 'm'
Commit a0590473c5e6 ("nfs: fix PNFS_FLEXFILE_LAYOUT Kconfig default")
turned the last 'm' into 'y' for the mips defconfig, and uncovered
this issue.
In this case, the module feature itself is enabled, but we have no
module to build. As a result, CONFIG_TRIM_UNUSED_KSYMS drops all the
instances of EXPORT_SYMBOL. Then, modpost wrongly assumes vmlinux is
missing because vmlinux.symvers is empty. (Or, you can create a module
that does not use any symbol of vmlinux).
The current behavior is to entirely suppress the unresolved symbol
warnings when vmlinux is missing just because there are too many.
I found the origin of this code in the historical git tree. [1]
If this is a matter of noisiness, I think modpost can display the
first 10 warnings, and the number of suppressed warnings at the end.
You will get a bit noisier logs when you run 'make modules' without
vmlinux, but such warnings are better to show because you never know
the resulting modules are actually loadable or not.
This commit changes the following:
- If any of input *.symver files is missing, pass -w option to let
the module build keep going with warnings instead of errors.
- If there are too many (10+) unresolved symbol warnings, show only
the first 10, and also the number of suppressed warnings.
Masahiro Yamada [Thu, 25 Mar 2021 18:54:09 +0000 (03:54 +0900)]
kbuild: generate Module.symvers only when vmlinux exists
The external module build shows the following warning if Module.symvers
is missing in the kernel tree.
WARNING: Symbol version dump "Module.symvers" is missing.
Modules may not have dependencies or modversions.
I think this is an important heads-up because the resulting modules may
not work as expected. This happens when you did not build the entire
kernel tree, for example, you might have prepared the minimal setups
for external modules by 'make defconfig && make modules_preapre'.
A problem is that 'make modules' creates Module.symvers even without
vmlinux. In this case, that warning is suppressed since Module.symvers
already exists in spite of its incomplete content.
The incomplete (i.e. invalid) Module.symvers should not be created.
This commit changes the second pass of modpost to dump symbols into
modules-only.symvers. The final Module.symvers is created by
concatenating vmlinux.symvers and modules-only.symvers if both exist.
Module.symvers is supposed to collect symbols from both vmlinux and
modules. It might be a bit confusing, and I am not quite sure if it
is an official interface, but presumably it is difficult to rename it
because some tools (e.g. kmod) parse it.
Masahiro Yamada [Wed, 24 Mar 2021 07:11:28 +0000 (16:11 +0900)]
arm64: move --fix-cortex-a53-843419 linker test to Kconfig
Since commit a14efe0d73eb ("kbuild: include Makefile.compiler only when
compiler is needed"), "make ARCH=arm64 (modules_)install" shows a false
positive warning.
Move the ld-option test to Kconfig, so that the result can be stored in
the .config file, avoiding multiple-time evaluations in the build and
installation time.
Masahiro Yamada [Mon, 15 Mar 2021 16:12:56 +0000 (01:12 +0900)]
kbuild: check the minimum assembler version in Kconfig
Documentation/process/changes.rst defines the minimum assembler version
(binutils version), but we have never checked it in the build time.
Kbuild never invokes 'as' directly because all assembly files in the
kernel tree are *.S, hence must be preprocessed. I do not expect
raw assembly source files (*.s) would be added to the kernel tree.
Therefore, we always use $(CC) as the assembler driver, and commit aa824e0c962b ("kbuild: remove AS variable") removed 'AS'. However,
we are still interested in the version of the assembler acting behind.
As usual, the --version option prints the version string.
$ as --version | head -n 1
GNU assembler (GNU Binutils for Ubuntu) 2.35.1
But, we do not have $(AS). So, we can add the -Wa prefix so that
$(CC) passes --version down to the backing assembler.
$ gcc -Wa,--version | head -n 1
gcc: fatal error: no input files
compilation terminated.
OK, we need to input something to satisfy gcc.
$ gcc -Wa,--version -c -x assembler /dev/null -o /dev/null | head -n 1
GNU assembler (GNU Binutils for Ubuntu) 2.35.1
The combination of Clang and GNU assembler works in the same way:
$ clang -no-integrated-as -Wa,--version -c -x assembler /dev/null -o /dev/null | head -n 1
GNU assembler (GNU Binutils for Ubuntu) 2.35.1
Clang with the integrated assembler fails like this:
For the last case, checking the error message is fragile. If the
proposal for -Wa,--version support [1] is accepted, this may not be
even an error in the future.
One easy way is to check if -integrated-as is present in the passed
arguments. We did not pass -integrated-as to CLANG_FLAGS before, but
we can make it explicit.
Nathan pointed out -integrated-as is the default for all of the
architectures/targets that the kernel cares about, but it goes
along with "explicit is better than implicit" policy. [2]
With all this in my mind, I implemented scripts/as-version.sh to
check the assembler version in Kconfig time.
$ scripts/as-version.sh gcc
GNU 23501
$ scripts/as-version.sh clang -no-integrated-as
GNU 23501
$ scripts/as-version.sh clang -integrated-as
LLVM 0
Masahiro Yamada [Sat, 13 Mar 2021 19:48:34 +0000 (04:48 +0900)]
kconfig: do not use allnoconfig_y option
allnoconfig_y is an ugly hack that sets a symbol to 'y' by allnoconfig.
allnoconfig does not mean a minimal set of CONFIG options because a
bunch of prompts are hidden by 'if EMBEDDED' or 'if EXPERT', but I do
not like to hack Kconfig this way.
Use the pre-existing feature, KCONFIG_ALLCONFIG, to provide a one
liner config fragment. CONFIG_EMBEDDED=y is still forced when
allnoconfig is invoked as a part of tinyconfig.
No change in the .config file produced by 'make tinyconfig'.
The output of 'make allnoconfig' will be changed; we will get
CONFIG_EMBEDDED=n because allnoconfig literally sets all symbols to n.
Masahiro Yamada [Sat, 13 Mar 2021 19:48:32 +0000 (04:48 +0900)]
kconfig: change defconfig_list option to environment variable
"defconfig_list" is a weird option that defines a static symbol that
declares the list of base config files in case the .config does not
exist yet.
This is quite different from other normal symbols; we just abused the
"string" type and the "default" properties to list out the input files.
They must be fixed values since these are searched for and loaded in
the parse stage.
It is an ugly hack, and should not exist in the first place. Providing
this feature as an environment variable is a saner approach.
Masahiro Yamada [Sat, 13 Mar 2021 19:48:25 +0000 (04:48 +0900)]
kconfig: refactor option parse code
The current option parse code is clumsy.
The 's' option is separately handled in an if-conditional due to the
following code:
input_mode = (enum input_mode)opt;
If 's' is moved to the switch statement, the invalid value 's' would
be assigned to the input_mode.
Another potential problem is that we are mixing 'enum input_mode' and
ASCII characters. They could overwrap if we add more input modes.
To separate them out, set the flag field of long options to a pointer
of input_mode_opt. For mode select options, getopt_long() returns 0,
which never causes overwrap with ASCII characters that represent short
options.
Masahiro Yamada [Mon, 15 Mar 2021 16:12:55 +0000 (01:12 +0900)]
kbuild: collect minimum tool versions into scripts/min-tool-version.sh
The kernel build uses various tools, many of which are provided by the
same software suite, for example, LLVM and Binutils.
When you raise the minimum version of Clang/LLVM, you need to update
clang_min_version in scripts/cc-version.sh and also lld_min_version in
scripts/ld-version.sh.
Kbuild can handle CC=clang and LD=ld.lld independently, but it does not
make much sense to maintain their versions separately.
Let's create a central place of minimum tool versions so you do not need
to touch multiple files. scripts/min-tool-version.sh prints the minimum
version of the given tool.
Nathan Chancellor [Tue, 9 Mar 2021 20:59:15 +0000 (13:59 -0700)]
Makefile: Only specify '--prefix=' when building with clang + GNU as
When building with LLVM_IAS=1, there is no point to specifying
'--prefix=' because that flag is only used to find GNU cross tools,
which will not be used indirectly when using the integrated assembler.
All of the tools are invoked directly from PATH or a full path specified
via the command line, which does not depend on the value of '--prefix='.
Sharing commands to reproduce issues becomes a little bit easier without
a '--prefix=' value because that '--prefix=' value is specific to a
user's machine due to it being an absolute path.
Some further notes from Fangrui Song:
clang can spawn GNU as (if -f?no-integrated-as is specified) and GNU
objcopy (-f?no-integrated-as and -gsplit-dwarf and -g[123]).
objcopy is only used for GNU as assembled object files.
With integrated assembler, the object file streamer creates .o and
.dwo simultaneously.
With GNU as, two objcopy commands are needed to extract .debug*.dwo to
.dwo files && another command to remove .debug*.dwo sections.
A small consequence of this change (to keep things simple) is that
'--prefix=' will always be specified now, even with a native build, when
it was not before. This should not be an issue due to the way that the
Makefile searches for the prefix (based on elfedit's location). This
ends up improving the experience for host builds because PATH is better
respected and matches GCC's behavior more closely. See the below thread
for more details:
Nathan Chancellor [Tue, 9 Mar 2021 20:59:14 +0000 (13:59 -0700)]
Makefile: Remove '--gcc-toolchain' flag
This flag was originally added to allow clang to find the GNU cross
tools in commit 785f11aa595b ("kbuild: Add better clang cross build
support"). This flag was not enough to find the tools at times so
'--prefix' was added to the list in commit ef8c4ed9db80 ("kbuild: allow
to use GCC toolchain not in Clang search path") and improved upon in
commit ca9b31f6bb9c ("Makefile: Fix GCC_TOOLCHAIN_DIR prefix for Clang
cross compilation"). Now that '--prefix' specifies a full path and
prefix, '--gcc-toolchain' serves no purpose because the kernel builds
with '-nostdinc' and '-nostdlib'.
This has been verified with self compiled LLVM 10.0.1 and LLVM 13.0.0 as
well as a distribution version of LLVM 11.1.0 without binutils in the
LLVM toolchain locations.
Link: https://reviews.llvm.org/D97902 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Fangrui Song <maskray@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Masahiro Yamada [Sat, 6 Mar 2021 06:11:21 +0000 (15:11 +0900)]
kbuild: move $(strip ) to suffix-search definition
Move $(strip ...) to the callee from the callers of suffix-search. It
shortens the code slightly. Adding a space after a comma will not be
a matter. I also dropped parentheses from single character variables.
Rasmus Villemoes [Fri, 5 Mar 2021 10:02:12 +0000 (11:02 +0100)]
kbuild: apply fixdep logic to link-vmlinux.sh
The patch adding CONFIG_VMLINUX_MAP revealed a small defect in the
build system: link-vmlinux.sh takes decisions based on CONFIG_*
options, but changing one of those does not always lead to vmlinux
being linked again.
For most of the CONFIG_* knobs referenced previously, this has
probably been hidden by those knobs also affecting some object file,
hence indirectly also vmlinux.
But CONFIG_VMLINUX_MAP is only handled inside link-vmlinux.sh, and
changing CONFIG_VMLINUX_MAP=n to CONFIG_VMLINUX_MAP=y does not cause
the build system to re-link (and hence have vmlinux.map
emitted). Since that map file is mostly a debugging aid, this is
merely a nuisance which is easily worked around by just deleting
vmlinux and building again.
But one could imagine other (possibly future) CONFIG options that
actually do affect the vmlinux binary but which are not captured
through some object file dependency.
To fix this, make link-vmlinux.sh emit a .vmlinux.d file in the same
format as the dependency files generated by gcc, and apply the fixdep
logic to that. I've tested that this correctly works with both in-tree
and out-of-tree builds.
Rasmus Villemoes [Fri, 5 Mar 2021 09:27:07 +0000 (10:27 +0100)]
kbuild: add CONFIG_VMLINUX_MAP expert option
It can be quite useful to have ld emit a link map file, in order to
debug or verify that special sections end up where they are supposed
to, and to see what LD_DEAD_CODE_DATA_ELIMINATION manages to get rid
of.
The only reason I'm not just adding this unconditionally is that the
.map file can be rather large (several MB), and that's a waste of
space when one isn't interested in these things. Also make it depend
on CONFIG_EXPERT.
Masahiro Yamada [Tue, 2 Mar 2021 14:26:14 +0000 (23:26 +0900)]
kbuild: show warning if 'make headers_check' is used
Since commit 7ecaf069da52 ("kbuild: move headers_check rule to
usr/include/Makefile"), 'make headers_check' is no-op.
This stub target is remaining here in case some scripts still invoke it.
In order to prompt people to remove stale code, show a noisy warning
message if used. The stub will be really removed after the Linux 5.15
release.
Masahiro Yamada [Sun, 28 Feb 2021 06:10:28 +0000 (15:10 +0900)]
kbuild: include Makefile.compiler only when compiler is needed
Since commit f2f02ebd8f38 ("kbuild: improve cc-option to clean up all
temporary files"), running 'make kernelversion' in a read-only source
tree emits a bunch of warnings:
Non-build targets such as kernelversion, clean, help, etc. do not
need to evaluate $(call cc-option,) or friends. Skip Makefile.compiler
so $(call cc-option,) becomes no-op.
This not only fixes the warnings, but also runs non-build targets much
faster.
Basically, all installation targets should also be non-build targets.
Unfortunately, vdso_install requires the compiler because it builds
vdso before installtion. This is a problem that must be fixed by a
separate patch.
Reported-by: Israel Tsadok <itsadok@gmail.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Masahiro Yamada [Sun, 28 Feb 2021 06:10:26 +0000 (15:10 +0900)]
kbuild: prefix $(srctree)/ to some included Makefiles
VPATH is used in Kbuild to make pattern rules search for prerequisites
in both $(objtree) and $(srctree). Some of *.c, *.S files are not real
sources, but generated by tools such as flex, bison, perl.
In contrast, I doubt the benefit of --include-dir=$(abs_srctree) because
it is always clear which Makefiles are real sources, and which are not.
So, my hope is to add $(srctree)/ prefix to all check-in Makefiles,
then remove --include-dir=$(abs_srctree) flag in the future.
I am touching only some Kbuild core parts for now. Treewide fixes will
be needed to achieve this goal.
Alexey Dobriyan [Sun, 14 Mar 2021 20:51:14 +0000 (23:51 +0300)]
prctl: fix PR_SET_MM_AUXV kernel stack leak
Doing a
prctl(PR_SET_MM, PR_SET_MM_AUXV, addr, 1);
will copy 1 byte from userspace to (quite big) on-stack array
and then stash everything to mm->saved_auxv.
AT_NULL terminator will be inserted at the very end.
/proc/*/auxv handler will find that AT_NULL terminator
and copy original stack contents to userspace.
Linus Torvalds [Sun, 14 Mar 2021 20:33:33 +0000 (13:33 -0700)]
Merge tag 'irq-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"A set of irqchip updates:
- Make the GENERIC_IRQ_MULTI_HANDLER configuration correct
- Add a missing DT compatible string for the Ingenic driver
- Remove the pointless debugfs_file pointer from struct irqdomain"
* tag 'irq-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/ingenic: Add support for the JZ4760
dt-bindings/irq: Add compatible string for the JZ4760B
irqchip: Do not blindly select CONFIG_GENERIC_IRQ_MULTI_HANDLER
ARM: ep93xx: Select GENERIC_IRQ_MULTI_HANDLER directly
irqdomain: Remove debugfs_file from struct irq_domain
Linus Torvalds [Sun, 14 Mar 2021 20:29:38 +0000 (13:29 -0700)]
Merge tag 'timers-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
"A single fix in for hrtimers to prevent an interrupt storm caused by
the lack of reevaluation of the timers which expire in softirq context
under certain circumstances, e.g. when the clock was set"
* tag 'timers-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Update softirq_expires_next correctly after __hrtimer_get_next_event()
Linus Torvalds [Sun, 14 Mar 2021 20:15:55 +0000 (13:15 -0700)]
Merge tag 'objtool-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fix from Thomas Gleixner:
"A single objtool fix to handle the PUSHF/POPF validation correctly for
the paravirt changes which modified arch_local_irq_restore not to use
popf"
* tag 'objtool-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool,x86: Fix uaccess PUSHF/POPF validation
Linus Torvalds [Sun, 14 Mar 2021 20:03:21 +0000 (13:03 -0700)]
Merge tag 'locking-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
"A couple of locking fixes:
- A fix for the static_call mechanism so it handles unaligned
addresses correctly.
- Make u64_stats_init() a macro so every instance gets a seperate
lockdep key.
- Make seqcount_latch_init() a macro as well to preserve the static
variable which is used for the lockdep key"
* tag 'locking-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
seqlock,lockdep: Fix seqcount_latch_init()
u64_stats,lockdep: Fix u64_stats_init() vs lockdep
static_call: Fix the module key fixup
Linus Torvalds [Sun, 14 Mar 2021 19:57:17 +0000 (12:57 -0700)]
Merge tag 'perf_urgent_for_v5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Make sure PMU internal buffers are flushed for per-CPU events too and
properly handle PID/TID for large PEBS.
- Handle the case properly when there's no PMU and therefore return an
empty list of perf MSRs for VMX to switch instead of reading random
garbage from the stack.
* tag 'perf_urgent_for_v5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/perf: Use RET0 as default for guest_get_msrs to handle "no PMU" case
perf/x86/intel: Set PERF_ATTACH_SCHED_CB for large PEBS and LBR
perf/core: Flush PMU internal buffers for per-CPU events
Linus Torvalds [Sun, 14 Mar 2021 19:54:56 +0000 (12:54 -0700)]
Merge tag 'efi-urgent-for-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI fix from Ard Biesheuvel via Borislav Petkov:
"Fix an oversight in the handling of EFI_RT_PROPERTIES_TABLE, which was
added v5.10, but failed to take the SetVirtualAddressMap() RT service
into account"
* tag 'efi-urgent-for-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: stub: omit SetVirtualAddressMap() if marked unsupported in RT_PROP table
Linus Torvalds [Sun, 14 Mar 2021 19:48:10 +0000 (12:48 -0700)]
Merge tag 'x86_urgent_for_v5.12_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- A couple of SEV-ES fixes and robustifications: verify usermode stack
pointer in NMI is not coming from the syscall gap, correctly track
IRQ states in the #VC handler and access user insn bytes atomically
in same handler as latter cannot sleep.
- Balance 32-bit fast syscall exit path to do the proper work on exit
and thus not confuse audit and ptrace frameworks.
- Two fixes for the ORC unwinder going "off the rails" into KASAN
redzones and when ORC data is missing.
* tag 'x86_urgent_for_v5.12_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sev-es: Use __copy_from_user_inatomic()
x86/sev-es: Correctly track IRQ states in runtime #VC handler
x86/sev-es: Check regs->sp is trusted before adjusting #VC IST stack
x86/sev-es: Introduce ip_within_syscall_gap() helper
x86/entry: Fix entry/exit mismatch on failed fast 32-bit syscalls
x86/unwind/orc: Silence warnings caused by missing ORC data
x86/unwind/orc: Disable KASAN checking in the ORC unwinder, part 2
Linus Torvalds [Sun, 14 Mar 2021 19:37:43 +0000 (12:37 -0700)]
Merge tag 'powerpc-5.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Some more powerpc fixes for 5.12:
- Fix wrong instruction encoding for lis in ppc_function_entry(),
which could potentially lead to missed kprobes.
- Fix SET_FULL_REGS on 32-bit and 64e, which prevented ptrace of
non-volatile GPRs immediately after exec.
- Clean up a missed SRR specifier in the recent interrupt rework.
- Don't treat unrecoverable_exception() as an interrupt handler, it's
called from other handlers so shouldn't do the interrupt entry/exit
accounting itself.
- Fix build errors caused by missing declarations for
[en/dis]able_kernel_vsx().
Thanks to Christophe Leroy, Daniel Axtens, Geert Uytterhoeven, Jiri
Olsa, Naveen N. Rao, and Nicholas Piggin"
* tag 'powerpc-5.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/traps: unrecoverable_exception() is not an interrupt handler
powerpc: Fix missing declaration of [en/dis]able_kernel_vsx()
powerpc/64s/exception: Clean up a missed SRR specifier
powerpc: Fix inverted SET_FULL_REGS bitop
powerpc/64s: Use symbolic macros for function entry encoding
powerpc/64s: Fix instruction encoding for lis in ppc_function_entry()
Linus Torvalds [Sun, 14 Mar 2021 19:35:02 +0000 (12:35 -0700)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"More fixes for ARM and x86"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: LAPIC: Advancing the timer expiration on guest initiated write
KVM: x86/mmu: Skip !MMU-present SPTEs when removing SP in exclusive mode
KVM: kvmclock: Fix vCPUs > 64 can't be online/hotpluged
kvm: x86: annotate RCU pointers
KVM: arm64: Fix exclusive limit for IPA size
KVM: arm64: Reject VM creation when the default IPA size is unsupported
KVM: arm64: Ensure I-cache isolation between vcpus of a same VM
KVM: arm64: Don't use cbz/adr with external symbols
KVM: arm64: Fix range alignment when walking page tables
KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility
KVM: arm64: Rename __vgic_v3_get_ich_vtr_el2() to __vgic_v3_get_gic_config()
KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is available
KVM: arm64: Turn kvm_arm_support_pmu_v3() into a static key
KVM: arm64: Fix nVHE hyp panic host context restore
KVM: arm64: Avoid corrupting vCPU context register in guest exit
KVM: arm64: nvhe: Save the SPE context early
kvm: x86: use NULL instead of using plain integer as pointer
KVM: SVM: Connect 'npt' module param to KVM's internal 'npt_enabled'
KVM: x86: Ensure deadline timer has truly expired before posting its IRQ
Linus Torvalds [Sun, 14 Mar 2021 19:23:34 +0000 (12:23 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"28 patches.
Subsystems affected by this series: mm (memblock, pagealloc, hugetlb,
highmem, kfence, oom-kill, madvise, kasan, userfaultfd, memcg, and
zram), core-kernel, kconfig, fork, binfmt, MAINTAINERS, kbuild, and
ia64"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (28 commits)
zram: fix broken page writeback
zram: fix return value on writeback_store
mm/memcg: set memcg when splitting page
mm/memcg: rename mem_cgroup_split_huge_fixup to split_page_memcg and add nr_pages argument
ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) sign
ia64: fix ia64_syscall_get_set_arguments() for break-based syscalls
mm/userfaultfd: fix memory corruption due to writeprotect
kasan: fix KASAN_STACK dependency for HW_TAGS
kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC
mm/madvise: replace ptrace attach requirement for process_madvise
include/linux/sched/mm.h: use rcu_dereference in in_vfork()
kfence: fix reports if constant function prefixes exist
kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations
kfence: fix printk format for ptrdiff_t
linux/compiler-clang.h: define HAVE_BUILTIN_BSWAP*
MAINTAINERS: exclude uapi directories in API/ABI section
binfmt_misc: fix possible deadlock in bm_register_write
mm/highmem.c: fix zero_user_segments() with start > end
hugetlb: do early cow when page pinned on src mm
mm: use is_cow_mapping() across tree where proper
...
Thomas Gleixner [Sun, 14 Mar 2021 15:34:35 +0000 (16:34 +0100)]
Merge tag 'irqchip-fixes-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent
Pull irqchip fixes from Marc Zyngier:
- More compatible strings for the Ingenic irqchip (introducing the
JZ4760B SoC)
- Select GENERIC_IRQ_MULTI_HANDLER on the ARM ep93xx platform
- Drop all GENERIC_IRQ_MULTI_HANDLER selections from the irqchip
Kconfig, now relying on the architecture to get it right
- Drop the debugfs_file field from struct irq_domain, now that
debugfs can track things on its own
Linus Torvalds [Sat, 13 Mar 2021 20:38:44 +0000 (12:38 -0800)]
Merge tag 'char-misc-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are some small misc/char driver fixes to resolve some reported
problems:
- habanalabs driver fixes
- Acrn build fixes (reported many times)
- pvpanic module table export fix
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
misc/pvpanic: Export module FDT device table
misc: fastrpc: restrict user apps from sending kernel RPC messages
virt: acrn: Correct type casting of argument of copy_from_user()
virt: acrn: Use EPOLLIN instead of POLLIN
virt: acrn: Use vfs_poll() instead of f_op->poll()
virt: acrn: Make remove_cpu sysfs invisible with !CONFIG_HOTPLUG_CPU
cpu/hotplug: Fix build error of using {add,remove}_cpu() with !CONFIG_SMP
habanalabs: fix debugfs address translation
habanalabs: Disable file operations after device is removed
habanalabs: Call put_pid() when releasing control device
drivers: habanalabs: remove unused dentry pointer for debugfs files
habanalabs: mark hl_eq_inc_ptr() as static
Linus Torvalds [Sat, 13 Mar 2021 20:36:53 +0000 (12:36 -0800)]
Merge tag 'staging-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver fixes from Greg KH:
"Here are some small staging driver fixes for reported problems. They
include:
- wfx header file cleanup patch reverted as it could cause problems
- comedi driver endian fixes
- buffer overflow problems for staging wifi drivers
- build dependency issue for rtl8192e driver
All have been in linux-next for a while with no reported problems"
* tag 'staging-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (23 commits)
Revert "staging: wfx: remove unused included header files"
staging: rtl8188eu: prevent ->ssid overflow in rtw_wx_set_scan()
staging: rtl8188eu: fix potential memory corruption in rtw_check_beacon_data()
staging: rtl8192u: fix ->ssid overflow in r8192_wx_set_scan()
staging: comedi: pcl726: Use 16-bit 0 for interrupt data
staging: comedi: ni_65xx: Use 16-bit 0 for interrupt data
staging: comedi: ni_6527: Use 16-bit 0 for interrupt data
staging: comedi: comedi_parport: Use 16-bit 0 for interrupt data
staging: comedi: amplc_pc236_common: Use 16-bit 0 for interrupt data
staging: comedi: pcl818: Fix endian problem for AI command data
staging: comedi: pcl711: Fix endian problem for AI command data
staging: comedi: me4000: Fix endian problem for AI command data
staging: comedi: dmm32at: Fix endian problem for AI command data
staging: comedi: das800: Fix endian problem for AI command data
staging: comedi: das6402: Fix endian problem for AI command data
staging: comedi: adv_pci1710: Fix endian problem for AI command data
staging: comedi: addi_apci_1500: Fix endian problem for command sample
staging: comedi: addi_apci_1032: Fix endian problem for COS sample
staging: ks7010: prevent buffer overflow in ks_wlan_set_scan()
staging: rtl8712: Fix possible buffer overflow in r8712_sitesurvey_cmd
...
Linus Torvalds [Sat, 13 Mar 2021 20:34:29 +0000 (12:34 -0800)]
Merge tag 'tty-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are some small tty and serial driver fixes to resolve some
reported problems:
- led tty trigger fixes based on review and were acked by the led
maintainer
- revert a max310x serial driver patch as it was causing problems
- revert a pty change as it was also causing problems
All of these have been in linux-next for a while with no reported
problems"
* tag 'tty-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
Revert "drivers:tty:pty: Fix a race causing data loss on close"
Revert "serial: max310x: rework RX interrupt handling"
leds: trigger/tty: Use led_set_brightness_sync() from workqueue
leds: trigger: Fix error path to not unlock the unlocked mutex
Linus Torvalds [Sat, 13 Mar 2021 20:32:57 +0000 (12:32 -0800)]
Merge tag 'usb-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are a small number of USB fixes for 5.12-rc3 to resolve a bunch
of reported issues:
- usbip fixups for issues found by syzbot
- xhci driver fixes and quirk additions
- gadget driver fixes
- dwc3 QCOM driver fix
- usb-serial new ids and fixes
- usblp fix for a long-time issue
- cdc-acm quirk addition
- other tiny fixes for reported problems
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (25 commits)
xhci: Fix repeated xhci wake after suspend due to uncleared internal wake state
usb: xhci: Fix ASMedia ASM1042A and ASM3242 DMA addressing
xhci: Improve detection of device initiated wake signal.
usb: xhci: do not perform Soft Retry for some xHCI hosts
usbip: fix vudc usbip_sockfd_store races leading to gpf
usbip: fix vhci_hcd attach_store() races leading to gpf
usbip: fix stub_dev usbip_sockfd_store() races leading to gpf
usbip: fix vudc to check for stream socket
usbip: fix vhci_hcd to check for stream socket
usbip: fix stub_dev to check for stream socket
usb: dwc3: qcom: Add missing DWC3 OF node refcount decrement
USB: usblp: fix a hang in poll() if disconnected
USB: gadget: udc: s3c2410_udc: fix return value check in s3c2410_udc_probe()
usb: renesas_usbhs: Clear PIPECFG for re-enabling pipe with other EPNUM
usb: dwc3: qcom: Honor wakeup enabled/disabled state
usb: gadget: f_uac1: stop playback on function disable
usb: gadget: f_uac2: always increase endpoint max_packet_size by one audio slot
USB: gadget: u_ether: Fix a configfs return code
usb: dwc3: qcom: add ACPI device id for sc8180x
Goodix Fingerprint device is not a modem
...
Linus Torvalds [Sat, 13 Mar 2021 20:26:22 +0000 (12:26 -0800)]
Merge tag 'erofs-for-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fix from Gao Xiang:
"Fix an urgent regression introduced by commit baa2c7c97153 ("block:
set .bi_max_vecs as actual allocated vector number"), which could
cause unexpected hung since linux 5.12-rc1.
Resolve it by avoiding using bio->bi_max_vecs completely"
* tag 'erofs-for-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: fix bio->bi_max_vecs behavior change
Linus Torvalds [Sat, 13 Mar 2021 20:18:59 +0000 (12:18 -0800)]
Merge tag 'kbuild-fixes-v5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- avoid 'make image_name' invoking syncconfig
- fix a couple of bugs in scripts/dummy-tools
- fix LLD_VENDOR and locale issues in scripts/ld-version.sh
- rebuild GCC plugins when the compiler is upgraded
- allow LTO to be enabled with KASAN_HW_TAGS
- allow LTO to be enabled without LLVM=1
* tag 'kbuild-fixes-v5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: fix ld-version.sh to not be affected by locale
kbuild: remove meaningless parameter to $(call if_changed_rule,dtc)
kbuild: remove LLVM=1 test from HAS_LTO_CLANG
kbuild: remove unneeded -O option to dtc
kbuild: dummy-tools: adjust to scripts/cc-version.sh
kbuild: Allow LTO to be selected with KASAN_HW_TAGS
kbuild: dummy-tools: support MPROFILE_KERNEL checks for ppc
kbuild: rebuild GCC plugins when the compiler is upgraded
kbuild: Fix ld-version.sh script if LLD was built with LLD_VENDOR
kbuild: dummy-tools: fix inverted tests for gcc
kbuild: add image_name to no-sync-config-targets
Minchan Kim [Sat, 13 Mar 2021 05:08:41 +0000 (21:08 -0800)]
zram: fix broken page writeback
commit 0d8359620d9b ("zram: support page writeback") introduced two
problems. It overwrites writeback_store's return value as kstrtol's
return value, which makes return value zero so user could see zero as
return value of write syscall even though it wrote data successfully.
It also breaks index value in the loop in that it doesn't increase the
index any longer. It means it can write only first starting block index
so user couldn't write all idle pages in the zram so lose memory saving
chance.
This patch fixes those issues.
Link: https://lkml.kernel.org/r/20210312173949.2197662-2-minchan@kernel.org Fixes: 0d8359620d9b("zram: support page writeback") Signed-off-by: Minchan Kim <minchan@kernel.org> Reported-by: Amos Bianchi <amosbianchi@google.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: John Dias <joaodias@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Minchan Kim [Sat, 13 Mar 2021 05:08:38 +0000 (21:08 -0800)]
zram: fix return value on writeback_store
writeback_store's return value is overwritten by submit_bio_wait's return
value. Thus, writeback_store will return zero since there was no IO
error. In the end, write syscall from userspace will see the zero as
return value, which could make the process stall to keep trying the write
until it will succeed.
Link: https://lkml.kernel.org/r/20210312173949.2197662-1-minchan@kernel.org Fixes: 3b82a051c101("drivers/block/zram/zram_drv.c: fix error return codes not being returned in writeback_store") Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: John Dias <joaodias@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhou Guanghui [Sat, 13 Mar 2021 05:08:33 +0000 (21:08 -0800)]
mm/memcg: set memcg when splitting page
As described in the split_page() comment, for the non-compound high order
page, the sub-pages must be freed individually. If the memcg of the first
page is valid, the tail pages cannot be uncharged when be freed.
For example, when alloc_pages_exact is used to allocate 1MB continuous
physical memory, 2MB is charged(kmemcg is enabled and __GFP_ACCOUNT is
set). When make_alloc_exact free the unused 1MB and free_pages_exact free
the applied 1MB, actually, only 4KB(one page) is uncharged.
Therefore, the memcg of the tail page needs to be set when splitting a
page.
Michel:
There are at least two explicit users of __GFP_ACCOUNT with
alloc_exact_pages added recently. See 7efe8ef274024 ("KVM: arm64:
Allocate stage-2 pgd pages with GFP_KERNEL_ACCOUNT") and c419621873713
("KVM: s390: Add memcg accounting to KVM allocations"), so this is not
just a theoretical issue.
Link: https://lkml.kernel.org/r/20210304074053.65527-3-zhouguanghui1@huawei.com Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Rui Xiang <rui.xiang@huawei.com> Cc: Tianhong Ding <dingtianhong@huawei.com> Cc: Weilong Chen <chenweilong@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhou Guanghui [Sat, 13 Mar 2021 05:08:30 +0000 (21:08 -0800)]
mm/memcg: rename mem_cgroup_split_huge_fixup to split_page_memcg and add nr_pages argument
Rename mem_cgroup_split_huge_fixup to split_page_memcg and explicitly pass
in page number argument.
In this way, the interface name is more common and can be used by
potential users. In addition, the complete info(memcg and flag) of the
memcg needs to be set to the tail pages.
Link: https://lkml.kernel.org/r/20210304074053.65527-2-zhouguanghui1@huawei.com Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Tianhong Ding <dingtianhong@huawei.com> Cc: Weilong Chen <chenweilong@huawei.com> Cc: Rui Xiang <rui.xiang@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergei Trofimovich [Sat, 13 Mar 2021 05:08:23 +0000 (21:08 -0800)]
ia64: fix ia64_syscall_get_set_arguments() for break-based syscalls
In https://bugs.gentoo.org/769614 Dmitry noticed that
`ptrace(PTRACE_GET_SYSCALL_INFO)` does not work for syscalls called via
glibc's syscall() wrapper.
ia64 has two ways to call syscalls from userspace: via `break` and via
`eps` instructions.
The difference is in stack layout:
1. `eps` creates simple stack frame: no locals, in{0..7} == out{0..8}
2. `break` uses userspace stack frame: may be locals (glibc provides
one), in{0..7} == out{0..8}.
Both work fine in syscall handling cde itself.
But `ptrace(PTRACE_GET_SYSCALL_INFO)` uses unwind mechanism to
re-extract syscall arguments but it does not account for locals.
The change always skips locals registers. It should not change `eps`
path as kernel's handler already enforces locals=0 and fixes `break`.
Tested on v5.10 on rx3600 machine (ia64 9040 CPU).
Link: https://lkml.kernel.org/r/20210221002554.333076-1-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Sat, 13 Mar 2021 05:08:17 +0000 (21:08 -0800)]
mm/userfaultfd: fix memory corruption due to writeprotect
Userfaultfd self-test fails occasionally, indicating a memory corruption.
Analyzing this problem indicates that there is a real bug since mmap_lock
is only taken for read in mwriteprotect_range() and defers flushes, and
since there is insufficient consideration of concurrent deferred TLB
flushes in wp_page_copy(). Although the PTE is flushed from the TLBs in
wp_page_copy(), this flush takes place after the copy has already been
performed, and therefore changes of the page are possible between the time
of the copy and the time in which the PTE is flushed.
To make matters worse, memory-unprotection using userfaultfd also poses a
problem. Although memory unprotection is logically a promotion of PTE
permissions, and therefore should not require a TLB flush, the current
userrfaultfd code might actually cause a demotion of the architectural PTE
permission: when userfaultfd_writeprotect() unprotects memory region, it
unintentionally *clears* the RW-bit if it was already set. Note that this
unprotecting a PTE that is not write-protected is a valid use-case: the
userfaultfd monitor might ask to unprotect a region that holds both
write-protected and write-unprotected PTEs.
The scenario that happens in selftests/vm/userfaultfd is as follows:
This race exists since commit 292924b26024 ("userfaultfd: wp: apply
_PAGE_UFFD_WP bit"). Yet, as Yu Zhao pointed, these races became apparent
since commit 09854ba94c6a ("mm: do_wp_page() simplification") which made
wp_page_copy() more likely to take place, specifically if page_count(page)
> 1.
To resolve the aforementioned races, check whether there are pending
flushes on uffd-write-protected VMAs, and if there are, perform a flush
before doing the COW.
Further optimizations will follow to avoid during uffd-write-unprotect
unnecassary PTE write-protection and TLB flushes.
Link: https://lkml.kernel.org/r/20210304095423.3825684-1-namit@vmware.com Fixes: 09854ba94c6a ("mm: do_wp_page() simplification") Signed-off-by: Nadav Amit <namit@vmware.com> Suggested-by: Yu Zhao <yuzhao@google.com> Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Peter Xu <peterx@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> [5.9+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Konovalov [Sat, 13 Mar 2021 05:08:13 +0000 (21:08 -0800)]
kasan: fix KASAN_STACK dependency for HW_TAGS
There's a runtime failure when running HW_TAGS-enabled kernel built with
GCC on hardware that doesn't support MTE. GCC-built kernels always have
CONFIG_KASAN_STACK enabled, even though stack instrumentation isn't
supported by HW_TAGS. Having that config enabled causes KASAN to issue
MTE-only instructions to unpoison kernel stacks, which causes the failure.
Fix the issue by disallowing CONFIG_KASAN_STACK when HW_TAGS is used.
(The commit that introduced CONFIG_KASAN_HW_TAGS specified proper
dependency for CONFIG_KASAN_STACK_ENABLE but not for CONFIG_KASAN_STACK.)
Andrey Konovalov [Sat, 13 Mar 2021 05:08:10 +0000 (21:08 -0800)]
kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC
Currently, kasan_free_nondeferred_pages()->kasan_free_pages() is called
after debug_pagealloc_unmap_pages(). This causes a crash when
debug_pagealloc is enabled, as HW_TAGS KASAN can't set tags on an
unmapped page.
This patch puts kasan_free_nondeferred_pages() before
debug_pagealloc_unmap_pages() and arch_free_page(), which can also make
the page unavailable.
Link: https://lkml.kernel.org/r/24cd7db274090f0e5bc3adcdc7399243668e3171.1614987311.git.andreyknvl@google.com Fixes: 94ab5b61ee16 ("kasan, arm64: enable CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Suren Baghdasaryan [Sat, 13 Mar 2021 05:08:06 +0000 (21:08 -0800)]
mm/madvise: replace ptrace attach requirement for process_madvise
process_madvise currently requires ptrace attach capability.
PTRACE_MODE_ATTACH gives one process complete control over another
process. It effectively removes the security boundary between the two
processes (in one direction). Granting ptrace attach capability even to a
system process is considered dangerous since it creates an attack surface.
This severely limits the usage of this API.
The operations process_madvise can perform do not affect the correctness
of the operation of the target process; they only affect where the data is
physically located (and therefore, how fast it can be accessed). What we
want is the ability for one process to influence another process in order
to optimize performance across the entire system while leaving the
security boundary intact.
Replace PTRACE_MODE_ATTACH with a combination of PTRACE_MODE_READ and
CAP_SYS_NICE. PTRACE_MODE_READ to prevent leaking ASLR metadata and
CAP_SYS_NICE for influencing process performance.
Link: https://lkml.kernel.org/r/20210303185807.2160264-1-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Jann Horn <jannh@google.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tim Murray <timmurray@google.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <stable@vger.kernel.org> [5.10+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matthew Wilcox (Oracle) [Sat, 13 Mar 2021 05:08:03 +0000 (21:08 -0800)]
include/linux/sched/mm.h: use rcu_dereference in in_vfork()
Fix a sparse warning by using rcu_dereference(). Technically this is a
bug and a sufficiently aggressive compiler could reload the `real_parent'
pointer outside the protection of the rcu lock (and access freed memory),
but I think it's pretty unlikely to happen.
Link: https://lkml.kernel.org/r/20210221194207.1351703-1-willy@infradead.org Fixes: b18dc5f291c0 ("mm, oom: skip vforked tasks from being selected") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marco Elver [Sat, 13 Mar 2021 05:08:00 +0000 (21:08 -0800)]
kfence: fix reports if constant function prefixes exist
Some architectures prefix all functions with a constant string ('.' on
ppc64). Add ARCH_FUNC_PREFIX, which may optionally be defined in
<asm/kfence.h>, so that get_stack_skipnr() can work properly.
Marco Elver [Sat, 13 Mar 2021 05:07:53 +0000 (21:07 -0800)]
kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations
cache_alloc_debugcheck_after() performs checks on an object, including
adjusting the returned pointer. None of this should apply to KFENCE
objects. While for non-bulk allocations, the checks are skipped when we
allocate via KFENCE, for bulk allocations cache_alloc_debugcheck_after()
is called via cache_alloc_debugcheck_after_bulk().
Fix it by skipping cache_alloc_debugcheck_after() for KFENCE objects.
Link: https://lkml.kernel.org/r/20210304205256.2162309-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Separating compiler-clang.h from compiler-gcc.h inadventently dropped the
definitions of the three HAVE_BUILTIN_BSWAP macros, which requires falling
back to the open-coded version and hoping that the compiler detects it.
Since all versions of clang support the __builtin_bswap interfaces, add
back the flags and have the headers pick these up automatically.
This results in a 4% improvement of compilation speed for arm defconfig.
Note: it might also be worth revisiting which architectures set
CONFIG_ARCH_USE_BUILTIN_BSWAP for one compiler or the other, today this is
set on six architectures (arm32, csky, mips, powerpc, s390, x86), while
another ten architectures define custom helpers (alpha, arc, ia64, m68k,
mips, nios2, parisc, sh, sparc, xtensa), and the rest (arm64, h8300,
hexagon, microblaze, nds32, openrisc, riscv) just get the unoptimized
version and rely on the compiler to detect it.
A long time ago, the compiler builtins were architecture specific, but
nowadays, all compilers that are able to build the kernel have correct
implementations of them, though some may not be as optimized as the inline
asm versions.
The patch that dropped the optimization landed in v4.19, so as discussed
it would be fairly safe to backport this revert to stable kernels to the
4.19/5.4/5.10 stable kernels, but there is a remaining risk for
regressions, and it has no known side-effects besides compile speed.
Link: https://lkml.kernel.org/r/20210226161151.2629097-1-arnd@kernel.org Link: https://lore.kernel.org/lkml/20210225164513.3667778-1-arnd@kernel.org/ Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Miguel Ojeda <ojeda@kernel.org> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Guo Ren <guoren@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Sami Tolvanen <samitolvanen@google.com> Cc: Marco Elver <elver@google.com> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Sat, 13 Mar 2021 05:07:44 +0000 (21:07 -0800)]
MAINTAINERS: exclude uapi directories in API/ABI section
Commit 7b4693e644cb ("MAINTAINERS: add uapi directories to API/ABI
section") added include/uapi/ and arch/*/include/uapi/ so that patches
modifying them CC linux-api. However that was already done in the past
and resulted in too much noise and thus later removed, as explained in b14fd334ff3d ("MAINTAINERS: trim the file triggers for ABI/API")
To prevent another round of addition and removal in the future, change the
entries to X: (explicit exclusion) for documentation purposes, although
they are not subdirectories of broader included directories, as there is
apparently no defined way to add plain comments in subsystem sections.
Link: https://lkml.kernel.org/r/20210301100255.25229-1-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Acked-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lior Ribak [Sat, 13 Mar 2021 05:07:41 +0000 (21:07 -0800)]
binfmt_misc: fix possible deadlock in bm_register_write
There is a deadlock in bm_register_write:
First, in the begining of the function, a lock is taken on the binfmt_misc
root inode with inode_lock(d_inode(root)).
Then, if the user used the MISC_FMT_OPEN_FILE flag, the function will call
open_exec on the user-provided interpreter.
open_exec will call a path lookup, and if the path lookup process includes
the root of binfmt_misc, it will try to take a shared lock on its inode
again, but it is already locked, and the code will get stuck in a deadlock
To reproduce the bug:
$ echo ":iiiii:E::ii::/proc/sys/fs/binfmt_misc/bla:F" > /proc/sys/fs/binfmt_misc/register
backtrace of where the lock occurs (#5):
0 schedule () at ./arch/x86/include/asm/current.h:15
1 0xffffffff81b51237 in rwsem_down_read_slowpath (sem=0xffff888003b202e0, count=<optimized out>, state=state@entry=2) at kernel/locking/rwsem.c:992
2 0xffffffff81b5150a in __down_read_common (state=2, sem=<optimized out>) at kernel/locking/rwsem.c:1213
3 __down_read (sem=<optimized out>) at kernel/locking/rwsem.c:1222
4 down_read (sem=<optimized out>) at kernel/locking/rwsem.c:1355
5 0xffffffff811ee22a in inode_lock_shared (inode=<optimized out>) at ./include/linux/fs.h:783
6 open_last_lookups (op=0xffffc9000022fe34, file=0xffff888004098600, nd=0xffffc9000022fd10) at fs/namei.c:3177
7 path_openat (nd=nd@entry=0xffffc9000022fd10, op=op@entry=0xffffc9000022fe34, flags=flags@entry=65) at fs/namei.c:3366
8 0xffffffff811efe1c in do_filp_open (dfd=<optimized out>, pathname=pathname@entry=0xffff8880031b9000, op=op@entry=0xffffc9000022fe34) at fs/namei.c:3396
9 0xffffffff811e493f in do_open_execat (fd=fd@entry=-100, name=name@entry=0xffff8880031b9000, flags=<optimized out>, flags@entry=0) at fs/exec.c:913
10 0xffffffff811e4a92 in open_exec (name=<optimized out>) at fs/exec.c:948
11 0xffffffff8124aa84 in bm_register_write (file=<optimized out>, buffer=<optimized out>, count=19, ppos=<optimized out>) at fs/binfmt_misc.c:682
12 0xffffffff811decd2 in vfs_write (file=file@entry=0xffff888004098500, buf=buf@entry=0xa758d0 ":iiiii:E::ii::i:CF
", count=count@entry=19, pos=pos@entry=0xffffc9000022ff10) at fs/read_write.c:603
13 0xffffffff811defda in ksys_write (fd=<optimized out>, buf=0xa758d0 ":iiiii:E::ii::i:CF
", count=19) at fs/read_write.c:658
14 0xffffffff81b49813 in do_syscall_64 (nr=<optimized out>, regs=0xffffc9000022ff58) at arch/x86/entry/common.c:46
15 0xffffffff81c0007c in entry_SYSCALL_64 () at arch/x86/entry/entry_64.S:120
To solve the issue, the open_exec call is moved to before the write
lock is taken by bm_register_write
Link: https://lkml.kernel.org/r/20210228224414.95962-1-liorribak@gmail.com Fixes: 948b701a607f1 ("binfmt_misc: add persistent opened binary handler for containers") Signed-off-by: Lior Ribak <liorribak@gmail.com> Acked-by: Helge Deller <deller@gmx.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
OGAWA Hirofumi [Sat, 13 Mar 2021 05:07:37 +0000 (21:07 -0800)]
mm/highmem.c: fix zero_user_segments() with start > end
zero_user_segments() is used from __block_write_begin_int(), for example
like the following
zero_user_segments(page, 4096, 1024, 512, 918)
But new the zero_user_segments() implementation for for HIGHMEM +
TRANSPARENT_HUGEPAGE doesn't handle "start > end" case correctly, and hits
BUG_ON(). (we can fix __block_write_begin_int() instead though, it is the
old and multiple usage)
Also it calls kmap_atomic() unnecessarily while start == end == 0.
Link: https://lkml.kernel.org/r/87v9ab60r4.fsf@mail.parknet.co.jp Fixes: 0060ef3b4e6d ("mm: support THPs in zero_user_segments") Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Matthew Wilcox <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / users / jedix / linux-maple.git / log