Commit Graph

916787 Commits

Author SHA1 Message Date
Masahiro Yamada
93fdddfefc kbuild: add this-makefile as a shorthand for $(lastword $(MAKEFILE_LIST))
Make it clearer, and self-documenting.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
827365ffda gcc-plugins: remove always-false $(if ...) in Makefile
This is the remnant of commit c17d6179ad ("gcc-plugins: remove unused
GCC_PLUGIN_SUBDIR").

The conditional $(if $(findstring /,$(p)),...) is always false because
none of plugins contains '/' in the file name.

Clean up the code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
2020-05-26 00:03:16 +09:00
Valdis Kl ē tnieks
9f64fbdb77 bpfilter: document build requirements for bpfilter_umh
It's not intuitively obvious that bpfilter_umh is a statically linked binary.
Mention the toolchain requirement in the Kconfig help, so people
have an easier time figuring out what's needed.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
6ce16f2bc8 scripts/checkstack.pl: fix arm sp regex
if objdump has below entries;
c01ed608 <X>:
c01ed614:       e24ddff7        sub     sp, sp, #120    ; 0x78

c01f0d50 <Y>:
c01f0d50:       e24dd094        sub     sp, sp, #140    ; 0x8c

scripts fails to read stack usage.
so making regex $re for ARM similar to aarch64

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
3311eeebae scripts/checkstack.pl: add arm push handling for stack usage
To count stack usage of push {*, fp, ip, lr, pc} instruction in ARM,
if FRAME POINTER is enabled.
e.g. c01f0d48: e92ddff0 push {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}

c01f0d50 <Y>:
c01f0d44:       e1a0c00d        mov     ip, sp
c01f0d48:       e92ddff0        push    {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}
c01f0d4c:       e24cb004        sub     fp, ip, #4
c01f0d50:       e24dd094        sub     sp, sp, #448    ; 0x1C0

$ cat dump | scripts/checkstack.pl arm
0xc01f0d50 Y []:                                        448

added subroutine frame work for this.
After change:
0xc01f0d500 Y []:                                       492

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
572220aad5 scripts/checkstack.pl: Add argument to print stacks greather than value.
Add arguments support to print stacks which are greater than
argument value only.

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
677f1410e0 scripts/checkstack.pl: don't display $dre as different entity
currently script prints stack usage for functions
in two ways:($re and $dre)

dre breaks sorting mechanism.
0xffffa00011f26f88 sunxi_mux_clk_setup.isra.0 [vmlinux]:Dynamic (0x140)
..
0xffffa00011f27210 sunxi_divs_clk_setup [vmlinux]:      Dynamic (0x1d0)

so we can print it in decimal only.

Also address before function name is changed to function
start address rather than stack consumption address.
Because in next patch, arm has two ways to use stack
which can be clubbed and printed in one function only.

All symbols whose stack by adding(re and dre) is greater than
100, will be printed.

0xffffa00011f2720c0 sunxi_divs_clk_setup [vmlinux]:     464
...
0xffffa00011f26f840 sunxi_mux_clk_setup.isra.0 [vmlinux]:320

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Gustavo A. R. Silva
859c817501 modpost,fixdep: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Siddharth Gupta
5967577231 scripts: headers_install: Exit with error on config leak
Misuse of CONFIG_* in UAPI headers should result in an error. These config
options can be set in userspace by the user application which includes
these headers to control the APIs and structures being used in a kernel
which supports multiple targets.

Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
0663c68c4d kbuild: remove {CLEAN,MRPROPER,DISTCLEAN}_DIRS
Merge {CLEAN,MRPROPER,DISTCLEAN}_DIRS into {CLEAN,MRPROPER,DISTCLEAN}_FILES
because the difference is just the -r option passed to the 'rm' command.

Do likewise as commit 1634f2bfdb ("kbuild: remove clean-dirs syntax").

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:15 +09:00
Masahiro Yamada
610134b750 kbuild: remove misleading stale FIXME comment
This comment was added by commit ("kbuild: Restore build nr, improve
vmlinux link") [1].

It was talking about if_changed_rule at that time. Now, it is unclear
what to fix.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=ea52ca1b3e3882b499cc6c043f384958b88b62ff
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:15 +09:00
Masahiro Yamada
3044dd0528 kbuild: invoke syncconfig if autoconf.h is missing
If include/generated/autoconf.h is accidentally lost somehow,
there is no clear way to fix it. Make it self-healing.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:15 +09:00
Masahiro Yamada
88a8e278ff samples: watchdog: use 'userprogs' syntax
Kbuild now supports the 'userprogs' syntax to compile userspace
programs for the same architecture as the kernel.

Add the entry to samples/Makefile to put this into the build bot
coverage.

I also added the CONFIG option guarded by 'depends on CC_CAN_LINK'
because $(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00
Masahiro Yamada
b98ccc7150 samples: timers: use 'userprogs' syntax
Kbuild now supports the 'userprogs' syntax to compile userspace
programs for the same architecture as the kernel.

Add the entry to samples/Makefile to put this into the build bot
coverage.

I also added the CONFIG option guarded by 'depends on CC_CAN_LINK'
because $(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00
Masahiro Yamada
87ffbba9a9 samples: auxdisplay: use 'userprogs' syntax
Kbuild now supports the 'userprogs' syntax to compile userspace
programs for the same architecture as the kernel.

Add the entry to samples/Makefile to put this into the build bot
coverage.

I also added the CONFIG option guarded by 'depends on CC_CAN_LINK'
because $(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00
Masahiro Yamada
c4c10996b1 samples: mei: build sample program for target architecture
This userspace program includes UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample program should be built for
the target as well. Kbuild now supports 'userprogs' for that.

I also guarded the CONFIG option by 'depends on CC_CAN_LINK' because
$(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00
Masahiro Yamada
60fb0b1239 samples: pidfd: build sample program for target architecture
This userspace program includes UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample program should be built for
the target as well. Kbuild now supports 'userprogs' for that.

I also guarded the CONFIG option by 'depends on CC_CAN_LINK' because
$(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00
Masahiro Yamada
28949b84b2 samples: vfs: build sample programs for target architecture
These userspace programs include UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample programs should be built for
the target as well. Kbuild now supports 'userprogs' for that.

I also guarded the CONFIG option by 'depends on CC_CAN_LINK' because
$(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00
Masahiro Yamada
37249f5945 samples: connector: build sample program for target architecture
This userspace program includes UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample program should be built for
the target as well. Kbuild now supports 'userprogs' for that.

$(CC) can always compile cn_text.o since it is the kenrel-space code,
but building ucon requires libc.

I guarded it by:

  always-$(CONFIG_CC_CAN_LINK) := $(userprogs)

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
82d00a9392 samples: hidraw: build sample program for target architecture
This userspace program includes UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample program should be built for
the target as well. Kbuild now supports 'userprogs' for that.

I also guarded the CONFIG option by 'depends on CC_CAN_LINK' because
$(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
87ecdf4fc9 samples: uhid: build sample program for target architecture
This userspace program includes UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample program should be built for
the target as well. Kbuild now supports 'userprogs' for that.

Add the entry to samples/Makefile to put this into the build bot
coverage.

I also added the CONFIG option guarded by 'depends on CC_CAN_LINK'
because $(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Sam Ravnborg
8a45fe7053 samples: uhid: fix warnings in uhid-example
Fix warnings seen when building for 32-bit architecture.

Use "%xd" for arguments of type size_t to fix the warnings.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
e079a08c60 kbuild: doc: document the new syntax 'userprogs'
Kbuild now supports the syntax 'userprogs' to compile userspace
programs for the same architecture as the kernel.

Insert the section '5 Userspace Program support' to explain it.

I copy-pasted '4 Host Program support' and fixed it up.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
f59e766877 samples: seccomp: build sample programs for target architecture
These userspace programs include UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample programs should be built for
the target as well. Kbuild now supports 'userprogs' for that.

I also guarded the CONFIG option by 'depends on CC_CAN_LINK' because
$(CC) may not provide libc.

The 'ifndef CROSS_COMPILE' is no longer needed.

BTW, the -m31 for s390 is left-over code. Commit 5a79859ae0 ("s390:
remove 31 bit support") killed it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
8a2cc0505c bpfilter: use 'userprogs' syntax to build bpfilter_umh
The user mode helper should be compiled for the same architecture as
the kernel.

This Makefile reused the 'hostprogs' syntax by overriding HOSTCC with CC.
Use the new syntax 'userprogs' to fix the Makefile mess.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
7f3a59db27 kbuild: add infrastructure to build userspace programs
Kbuild supports the infrastructure to build host programs, but there
was no support to build userspace programs for the target architecture
(i.e. the same architecture as the kernel).

Sam Ravnborg worked on this in 2014 (https://lkml.org/lkml/2014/7/13/154),
but it was not merged. One problem at that time was, there was no good way
to know whether $(CC) can link standalone programs. In fact, pre-built
kernel.org toolchains [1] are often used for building the kernel, but they
do not provide libc.

Now, we can handle this cleanly because the compiler capability is
evaluated at the Kconfig time. If $(CC) cannot link standalone programs,
the relevant options are hidden by 'depends on CC_CAN_LINK'.

The implementation just mimics scripts/Makefile.host

The userspace programs are compiled with the same flags as the host
programs. In addition, it uses -m32 or -m64 if it is found in
$(KBUILD_CFLAGS).

This new syntax has two usecases.

- Sample programs

  Several userspace programs under samples/ include UAPI headers
  installed in usr/include. Most of them were previously built for
  the host architecture just to use the 'hostprogs' syntax.

  However, 'make headers' always works for the target architecture.
  This caused the arch mismatch in cross-compiling. To fix this
  distortion, sample code should be built for the target architecture.

- Bpfilter

  net/bpfilter/Makefile compiles bpfilter_umh as the user mode helper,
  and embeds it into the kernel. Currently, it overrides HOSTCC with
  CC to use the 'hostprogs' syntax. This hack should go away.

[1]: https://mirrors.edge.kernel.org/pub/tools/crosstool/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
b1183b6dca bpfilter: check if $(CC) can link static libc in Kconfig
On Fedora, linking static glibc requires the glibc-static RPM package,
which is not part of the glibc-devel package.

CONFIG_CC_CAN_LINK does not check the capability of static linking,
so you can enable CONFIG_BPFILTER_UMH, then fail to build:

    HOSTLD  net/bpfilter/bpfilter_umh
  /usr/bin/ld: cannot find -lc
  collect2: error: ld returned 1 exit status

Add CONFIG_CC_CAN_LINK_STATIC, and make CONFIG_BPFILTER_UMH depend
on it.

Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
9371f86ecb bpfilter: match bit size of bpfilter_umh to that of the kernel
bpfilter_umh is built for the default machine bit of the compiler,
which may not match to the bit size of the kernel.

This happens in the scenario below:

You can use biarch GCC that defaults to 64-bit for building the 32-bit
kernel. In this case, Kbuild passes -m32 to teach the compiler to
produce 32-bit kernel space objects. However, it is missing when
building bpfilter_umh. It is built as a 64-bit ELF, and then embedded
into the 32-bit kernel.

The 32-bit kernel and 64-bit umh is a bad combination.

In theory, we can have 32-bit umh running on 64-bit kernel, but we do
not have a good reason to support such a usecase.

The best is to match the bit size between them.

Pass -m32 or -m64 to the umh build command if it is found in
$(KBUILD_CFLAGS). Evaluate CC_CAN_LINK against the kernel bit-size.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
59721d4eb7 kbuild: warn if always, hostprogs-y, or hostprogs-m is used
always, hostprogs-y, and hostprogs-m are deprecated.

There is no user in upstream code, but I will keep them for external
modules. I want to remove them entirely someday. Prompt downstream
users for the migration.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-17 18:51:28 +09:00
Masahiro Yamada
78046fabe6 kbuild: determine the output format of DTC by the target suffix
cmd_dtc takes the additional parameter $(2) to select the target
format, dtb or yaml. This makes things complicated when it is used
with cmd_and_fixdep and if_changed_rule. I actually stumbled on this.
See commit 3d4b223868 ("kbuild: fix DT binding schema rule again to
avoid needless rebuilds").

Extract the suffix part of the target instead of passing the parameter.
Fortunately, this works for both $(obj)/%.dtb and $(obj)/%.dt.yaml .

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
1ca0c2f612 kbuild: remove unused AS assignment
$(AS) is not used anywhere in the kernel build, hence commit
aa824e0c96 ("kbuild: remove AS variable") killed it.

Remove the left-over code in arch/{arm,arm64}/Makefile.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Will Deacon <will@kernel.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
ea21e90414 kbuild: remove '/' target
This notice has been here for a while. Remove it entirely now.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
85e4a889d3 Revert "objtool: Skip samples subdirectory"
This reverts commit 8728497895.

samples/ contains only sub-directories.

Because OBJECT_FILES_NON_STANDARD does not work recursively,
this line has no effect.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
9a95015466 kbuild: use CONFIG_CC_VERSION_TEXT to construct LINUX_COMPILER macro
scripts/mkcompile_h runs $(CC) just for getting the version string.
Reuse CONFIG_CC_VERSION_TEXT for optimization.

For GCC, this slightly changes the version string. I do not think it
is a big deal as we do not have the defined format for LINUX_COMPILER.
In fact, the recent commit 4dcc9a8844 ("kbuild: mkcompile_h:
Include $LD version in /proc/version") added the linker version.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
30a7729771 kbuild: use -MMD instead of -MD to exclude system headers from dependency
This omits system headers from the generated header dependency.

System headers are not updated unless you upgrade the compiler. Nor do
they contain CONFIG options, so fixdep does not need to parse them.

Having said that, the effect of this optimization will be quite small
because the kernel code generally does not include system headers
except <stdarg.h>. Host programs include a lot of system headers,
but there are not so many in the kernel tree.

At first, keeping system headers in .*.cmd files might be useful to
detect the compiler update, but there is no guarantee that <stdarg.h>
is included from every file. So, I implemented a more reliable way in
the previous commit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
8b59cd81dc kbuild: ensure full rebuild when the compiler is updated
Commit 21c54b7747 ("kconfig: show compiler version text in the top
comment") added the environment variable, CC_VERSION_TEXT in the comment
of the top Kconfig file. It can detect the compiler update, and invoke
the syncconfig because all environment variables referenced in Kconfig
files are recorded in include/config/auto.conf.cmd

This commit makes it a CONFIG option in order to ensure the full rebuild
when the compiler is updated.

This works like follows:

include/config/kconfig.h contains "CONFIG_CC_VERSION_TEXT" in the comment
block.

The top Makefile specifies "-include $(srctree)/include/linux/kconfig.h"
to guarantee it is included from all kernel source files.

fixdep parses every source file and all headers included from it,
searching for words prefixed with "CONFIG_". Then, fixdep finds
CONFIG_CC_VERSION_TEXT in include/config/kconfig.h and adds
include/config/cc/version/text.h into every .*.cmd file.

When the compiler is updated, syncconfig is invoked because init/Kconfig
contains the reference to the environment variable CC_VERTION_TEXT.
CONFIG_CC_VERSION_TEXT is updated to the new version string, and
include/config/cc/version/text.h is touched.

In the next rebuild, Make will rebuild every files since the timestamp
of include/config/cc/version/text.h is newer than that of target.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
e33ae3ed33 kbuild: use $(CC_VERSION_TEXT) to evaluate CC_IS_GCC and CC_IS_CLANG
The result of '$(CC) --version | head -n 1' has already been computed
by the top Makefile, and stored in the environment variable,
CC_VERSION_TEXT.

'echo' is cheaper than the two commands $(CC) and 'head' although this
optimization is not noticeable level.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
081b4b54ff unicore32: do not evaluate compiler's library path when cleaning
Since commit a83e4ca26a ("kbuild: remove cc-option switch from
-Wframe-larger-than="), 'make ARCH=unicore32 clean' emits error
messages as follows:

  $ make ARCH=unicore32 clean
  gcc: error: missing argument to '-Wframe-larger-than='
  gcc: error: missing argument to '-Wframe-larger-than='

We do not care compiler flags when cleaning.

Use the '=' operator for lazy expansion because we do not use
GNU_LIBC_A or GNU_LIBGCC_A when cleaning.

Fixes: a83e4ca26a ("kbuild: remove cc-option switch from -Wframe-larger-than=")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-05-12 13:28:33 +09:00
Masahiro Yamada
dc960bfeed h8300: suppress error messages for 'make clean'
'make ARCH=h8300 clean' emits error messages as follows:

  $ make ARCH=h8300 clean
  gcc: error: missing argument to '-Wframe-larger-than='
  gcc: error: unrecognized command line option '-mint32'

You can suppress the second one by setting the correct CROSS_COMPILE=,
but we should not require any compiler for cleaning.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:32 +09:00
Masahiro Yamada
6632fa8fca hexagon: suppress error message for 'make clean'
'make ARCH=hexagon clean' emits an error message as follows:

  $ make ARCH=hexagon clean
  gcc: error: unrecognized command line option '-G0'

You can suppress it by setting the correct CROSS_COMPILE=,
but we should not require any compiler for cleaning.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Brian Cain <bcain@codeaurora.org>
2020-05-12 13:28:32 +09:00
Masahiro Yamada
7e49afc032 um: do not evaluate compiler's library path when cleaning
Since commit a83e4ca26a ("kbuild: remove cc-option switch from
-Wframe-larger-than="), 'make ARCH=um clean' emits an error message
as follows:

  $ make ARCH=um clean
  gcc: error: missing argument to '-Wframe-larger-than='

We do not care compiler flags when cleaning.

Use the '=' operator for lazy expansion because we do not use
LDFLAGS_pcap.o or LDFLAGS_vde.o when cleaning.

While I was here, I removed the redundant -r option because it
already exists in the recipe.

Fixes: a83e4ca26a ("kbuild: remove cc-option switch from -Wframe-larger-than=")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com> [build]
2020-05-12 13:28:32 +09:00
Linus Torvalds
2ef96a5bb1 Linux 5.7-rc5 2020-05-10 15:16:58 -07:00
Linus Torvalds
c14cab2688 A set of fixes for x86:
- Ensure that direct mapping alias is always flushed when changing page
    attributes. The optimization for small ranges failed to do so when
    the virtual address was in the vmalloc or module space.
 
  - Unbreak the trace event registration for syscalls without arguments
    caused by the refactoring of the SYSCALL_DEFINE0() macro.
 
  - Move the printk in the TSC deadline timer code to a place where it is
    guaranteed to only be called once during boot and cannot be rearmed by
    clearing warn_once after boot. If it's invoked post boot then lockdep
    rightfully complains about a potential deadlock as the calling context
    is different.
 
  - A series of fixes for objtool and the ORC unwinder addressing variety
    of small issues:
 
      Stack offset tracking for indirect CFAs in objtool ignored subsequent
      pushs and pops
 
      Repair the unwind hints in the register clearing entry ASM code
 
      Make the unwinding in the low level exit to usermode code stop after
      switching to the trampoline stack. The unwind hint is not longer valid
      and the ORC unwinder emits a warning as it can't find the registers
      anymore.
 
      Fix the unwind hints in switch_to_asm() and rewind_stack_do_exit()
      which caused objtool to generate bogus ORC data.
 
      Prevent unwinder warnings when dumping the stack of a non-current
      task as there is no way to be sure about the validity because the
      dumped stack can be a moving target.
 
      Make the ORC unwinder behave the same way as the frame pointer
      unwinder when dumping an inactive tasks stack and do not skip the
      first frame.
 
      Prevent ORC unwinding before ORC data has been initialized
 
      Immediately terminate unwinding when a unknown ORC entry type is
      found.
 
      Prevent premature stop of the unwinder caused by IRET frames.
 
      Fix another infinite loop in objtool caused by a negative offset which
      was not catched.
 
      Address a few build warnings in the ORC unwinder and add missing
      static/ro_after_init annotations
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6363QTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoRJHD/4hWjzJLsUZ9xq2NrzhevoeJtxj+wVM
 66x9NM3mlFQ30BN4Aye4EnNEhR0iIvNPWWdfEmaJYfPHPwnUjjcOa426HYxP/WXA
 DWd5F20wGaaPOJ65LJpy/+pfcxAeQynt4I2cDEWHAplswfOWV/Hv8mSeKAKuq400
 lCWaTMkWcO/toexSNn8PVyWi9rHlm+76E1bHkVwuoekGBGt1VloKGlK6OPyElzL2
 w9VtrjSLlYQ0MdfCJKQeg44XQPMbf4hZRfc88x9SwDWB01q7aSvb0pWNl9AJKNXA
 7fFu5T4F4PABPgRM7eJ5yNk0De9jM1y+6eCp66f9UXoNOeSr7Boz9Xc4xWqAraIi
 9Dtx3WliO9CAxwUiD+Cj2iJO5o83AdRK/xhCth2VRnYMS6imfSidEqTC+LhEtkzw
 Yplu7sbrWQDa5JTh8vk60clDvbkU+pfdxJisY+KClRguWfQfR6MJNuQnE0NHr7cH
 H4VXFFHEE6tDdJneQ9RxA4iF20RTgSlJGK0YlsH6QsxPsRgoHVkGUao8fQhrNvRc
 MIdpm9YasWStjJ7ZXbDeStmnLFN3DCj1RC8wmvJ4i/R1sPnBvPvRUt4Lm988a951
 Vyr23VIcVrE7zykiqQZVH7bvIv6ULORqTJbIOF1rO/aIut4W8z0ojoVXC0Z7CiwF
 S5SGj+hlWciIew==
 =0rCi
 -----END PGP SIGNATURE-----

Merge tag 'x86-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for x86:

   - Ensure that direct mapping alias is always flushed when changing
     page attributes. The optimization for small ranges failed to do so
     when the virtual address was in the vmalloc or module space.

   - Unbreak the trace event registration for syscalls without arguments
     caused by the refactoring of the SYSCALL_DEFINE0() macro.

   - Move the printk in the TSC deadline timer code to a place where it
     is guaranteed to only be called once during boot and cannot be
     rearmed by clearing warn_once after boot. If it's invoked post boot
     then lockdep rightfully complains about a potential deadlock as the
     calling context is different.

   - A series of fixes for objtool and the ORC unwinder addressing
     variety of small issues:

       - Stack offset tracking for indirect CFAs in objtool ignored
         subsequent pushs and pops

       - Repair the unwind hints in the register clearing entry ASM code

       - Make the unwinding in the low level exit to usermode code stop
         after switching to the trampoline stack. The unwind hint is no
         longer valid and the ORC unwinder emits a warning as it can't
         find the registers anymore.

       - Fix unwind hints in switch_to_asm() and rewind_stack_do_exit()
         which caused objtool to generate bogus ORC data.

       - Prevent unwinder warnings when dumping the stack of a
         non-current task as there is no way to be sure about the
         validity because the dumped stack can be a moving target.

       - Make the ORC unwinder behave the same way as the frame pointer
         unwinder when dumping an inactive tasks stack and do not skip
         the first frame.

       - Prevent ORC unwinding before ORC data has been initialized

       - Immediately terminate unwinding when a unknown ORC entry type
         is found.

       - Prevent premature stop of the unwinder caused by IRET frames.

       - Fix another infinite loop in objtool caused by a negative
         offset which was not catched.

       - Address a few build warnings in the ORC unwinder and add
         missing static/ro_after_init annotations"

* tag 'x86-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/unwind/orc: Move ORC sorting variables under !CONFIG_MODULES
  x86/apic: Move TSC deadline timer debug printk
  ftrace/x86: Fix trace event registration for syscalls without arguments
  x86/mm/cpa: Flush direct map alias during cpa
  objtool: Fix infinite loop in for_offset_range()
  x86/unwind/orc: Fix premature unwind stoppage due to IRET frames
  x86/unwind/orc: Fix error path for bad ORC entry type
  x86/unwind/orc: Prevent unwinding before ORC initialization
  x86/unwind/orc: Don't skip the first frame for inactive tasks
  x86/unwind: Prevent false warnings for non-current tasks
  x86/unwind/orc: Convert global variables to static
  x86/entry/64: Fix unwind hints in rewind_stack_do_exit()
  x86/entry/64: Fix unwind hints in __switch_to_asm()
  x86/entry/64: Fix unwind hints in kernel exit path
  x86/entry/64: Fix unwind hints in register clearing code
  objtool: Fix stack offset tracking for indirect CFAs
2020-05-10 11:59:53 -07:00
Linus Torvalds
8b00083219 A single fix for objtool to prevent an infinite loop in the jump table
search which can be triggered when building the kernel with
 -ffunction-sections.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl635X8THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYod4AEACumK3x6NTRw7o889GU+Kzj/LfpJZOr
 QoKjZgo4AzeONa/5sKoBeNhGiHkuAOhhwG/yq9QrTMTw3b6kFPnQ8Vel590JM/uj
 j/qjgbpR5v2v0ULMbONEHBN/3dRETyFomAe88hg6WM7ZuNCXPd+rbya9XxD7LdQo
 K04y+vdPACJIf1hyb91sOWfyAWDHzwencNQ0qq0CMf72JpKFcRXCqor7vvH5zNH0
 2PmTbKasOlyrgb9HQNLi6mNNoM47bc9lg8D76eDBl/Wl3yqYVwAawk4vqgwjxc0P
 MetoybQsWegi2dzmhjk61MIF8h6vw/NM6xuyiXSW7dHCN1GXzWGojuSVfzv0AEj2
 0/xbRToSRWuPAvURGqiZ8GhBgG2ybHz+sDQyh/Cg4Jj2NulOLxy0lBngh5o/Dczh
 mLpqcJUd6I76bUSk+c0vehUqOEj0yAZm5Olo7gTkyoHlFSG0b2nShC1Km4TBM04A
 h5RTp/lBp++u1h4+w2EwyP8F6+chcpsyUQG1yEpz+GYoHsjYkA1gfx1rtD7uNKUI
 NwzVsuUEUt3UL4PPnjMMPYbOZb4R3vUjGFhgG5Se3D+2mNHkrvh+HA3WvUb5CUuW
 MSQ0e0K7Su3+M0/H+PQDKDPS/a0h3HtpZwaZt4gPkxnXNc5P7+c4Vyo28nttwF2O
 Ad08s6mVY8sDtA==
 =0+2v
 -----END PGP SIGNATURE-----

Merge tag 'objtool-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool fix from Thomas Gleixner:
 "A single fix for objtool to prevent an infinite loop in the
  jump table search which can be triggered when building the
  kernel with '-ffunction-sections'"

* tag 'objtool-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix infinite loop in find_jump_table()
2020-05-10 11:42:14 -07:00
Linus Torvalds
bd2049f871 A single fix for the fallout of the recent futex uacess rework.
With those changes GCC9 fails to analyze arch_futex_atomic_op_inuser()
 correctly and emits a 'maybe unitialized' warning. While we usually ignore
 compiler stupidity the conditional store is pointless anyway because the
 correct case has to store. For the fault case the extra store does no harm.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl635IgTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoTQkEAChNFCVLyCNihKNDar4h0LhuChYSVow
 CRpnLFKTrxWpUemHYgOQM8FBFRjvVK3o3yhmp7qyWc1LnM4iYuGleP+FhfL5F1mk
 t0ANUMFAZOomy4348XXeVR/bq7RFpKrD68tsl0u3nC+NzykN4kCt3n8qN0CendbH
 +j9ILi2eNEbSIarC4gH228UuN0YIY5nC9ftW9oHJ+c/Z23X9RXstXhiH1TB9w99E
 97G96WOdWjA+z7KzMF1REi/goJGxeZh0GQdz4iuR6vBNd4iR2V9hT3DqklUnSZPp
 +XGvaWaUH7yVa0etUdCtlBwmZ7Xq3h/N381khq9m6NfXdS8aZ7OavWyf+3urx7xz
 6GtCIlo0QnIyqx5oe1/06zxQNgNAf0JAKIi5IDLFsr8SwfoWoG1Z6RrAYugyZurm
 9RganJhVGrTXApi/9NUafhqHv7y9OE5UodRLpnKdnjei+/sE51xaIgx7Tr59Ao8n
 G3sMZkI/8GV9cQnKrg7qcN7kiJfyofoslnOigwm3hJaTMAn0fK9+Bx5YvJgVlyf2
 SmE3saw3408/hhqkVWCW5GL8J+JEh/WDi6FCZ3Fu+L1UHalzqDGKAlhfmVxxDNmt
 tDbP4AUHbucmcWl98Ms0iKtfSwz1H0kTfkaHS0cvphIfH593S4FDJEiywiKsab7v
 8nPUV2Bi6vZHxw==
 =Va5K
 -----END PGP SIGNATURE-----

Merge tag 'locking-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fix from Thomas Gleixner:
 "A single fix for the fallout of the recent futex uacess rework.

  With those changes GCC9 fails to analyze arch_futex_atomic_op_inuser()
  correctly and emits a 'maybe unitialized' warning. While we usually
  ignore compiler stupidity the conditional store is pointless anyway
  because the correct case has to store. For the fault case the extra
  store does no harm"

* tag 'locking-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM: futex: Address build warning
2020-05-10 11:39:31 -07:00
Linus Torvalds
27d2dcb1b9 IOMMU Fixes for Linux v5.7-rc4
Including:
 
 	- The race condition fixes for the AMD IOMMU driver. This are 5
 	  patches fixing two race conditions around
 	  increase_address_space(). The first race condition was around
 	  the non-atomic update of the domain page-table root pointer
 	  and the variable containing the page-table depth (called
 	  mode). This is fixed now be merging page-table root and mode
 	  into one 64-bit field which is read/written atomically.
 
 	  The second race condition was around updating the page-table
 	  root pointer and making it public before the hardware caches
 	  were flushed. This could cause addresses to be mapped and
 	  returned to drivers which are not reachable by IOMMU hardware
 	  yet, causing IO page-faults. This is fixed too by adding the
 	  necessary flushes before a new page-table root is published.
 
 	  Related to the race condition fixes these patches also add a
 	  missing domain_flush_complete() barrier to update_domain() and
 	  a fix to bail out of the loop which tries to increase the
 	  address space when the call to increase_address_space() fails.
 
 	  Qian was able to trigger the race conditions under high load
 	  and memory pressure within a few days of testing. He confirmed
 	  that he has seen no issues anymore with the fixes included
 	  here.
 
 	- Fix for a list-handling bug in the VirtIO IOMMU driver.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEr9jSbILcajRFYWYyK/BELZcBGuMFAl638MYACgkQK/BELZcB
 GuOQxQ/5AYorgKuGkqVbob69YWZuSAEG08dlzDw4C8CDnPKXEPd0L4gJGLP7BpEh
 bPJo9QJtXW7zG6Hhk8sWk9/iONsThngoudaQrodJwaQRdCDGaDZlvBaezG2Vx4xb
 A2OrcM9lvQSODdgyf3x0O1cX7vkQ4J6nJR1Z8Fw4EufjH6TS9DR0tf8ZWHtIpHa6
 Josu3M+qhUXPsn7KK5o7GtNib7sI4whLldYaASGsuaFGzod3CgA0cgmL2HfD+DWP
 k1EIEZTCaOq0BamtpyXbSA6o0AxwKERr/KONi1pL0xN4r0yCjsxEQ6+Rw4caqvgA
 zrfv3kk4a+wFAxOe0hUEtKk8Oy587LPJvIX4FnjG8hRnBrEaQC9vy4eMj05utPid
 PpsNQ35P+SyrxTlIp7ybIVhUvKbxih8SSpRsjx16vX+r/h4SRvWHzjpHVq/4+gIT
 TeZGw1g7xCIyjzn5HqLs/nMG/Ly9QHQaWia8slJJgbzI/deUXAVTy6PmMrqHB+zv
 e0PelKsq5lEQBrFX+r/Sg5hBViKaMykXKbXXg3KIolzlutJc2Rrzh4EEKpP/ug2/
 upTXf+NvMobNxb3QLqn3IJApIirEGYQqI7lwjiUwTC5xb3EfYLUuRa5i4fbOAZIv
 krsVM4sNX1S32TblTMzDDOEEggPG1wPhVF5B+1emOolYHek3ShI=
 =gqwr
 -----END PGP SIGNATURE-----

Merge tag 'iommu-fixes-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:

 - Race condition fixes for the AMD IOMMU driver.

   These are five patches fixing two race conditions around
   increase_address_space(). The first race condition was around the
   non-atomic update of the domain page-table root pointer and the
   variable containing the page-table depth (called mode). This is fixed
   now be merging page-table root and mode into one 64-bit field which
   is read/written atomically.

   The second race condition was around updating the page-table root
   pointer and making it public before the hardware caches were flushed.
   This could cause addresses to be mapped and returned to drivers which
   are not reachable by IOMMU hardware yet, causing IO page-faults. This
   is fixed too by adding the necessary flushes before a new page-table
   root is published.

   Related to the race condition fixes these patches also add a missing
   domain_flush_complete() barrier to update_domain() and a fix to bail
   out of the loop which tries to increase the address space when the
   call to increase_address_space() fails.

   Qian was able to trigger the race conditions under high load and
   memory pressure within a few days of testing. He confirmed that he
   has seen no issues anymore with the fixes included here.

 - Fix for a list-handling bug in the VirtIO IOMMU driver.

* tag 'iommu-fixes-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/virtio: Reverse arguments to list_add
  iommu/amd: Do not flush Device Table in iommu_map_page()
  iommu/amd: Update Device Table in increase_address_space()
  iommu/amd: Call domain_flush_complete() in update_domain()
  iommu/amd: Do not loop forever when trying to increase address space
  iommu/amd: Fix race in increase_address_space()/fetch_pte()
2020-05-10 11:26:23 -07:00
Linus Torvalds
0a85ed6e7f block-5.7-2020-05-09
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl63WVAQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpkXWD/9qJgqQpPkigCCwwPHZ+phthw6gHeAgBxPH
 Cw6P9QB4QCdacZjQA6QH3zdxaDsCCitQRioWPgxngs1326TKYNzBi7U3eTEwiK12
 cnRybLnkzei4yzYVUSJk637oOoQh3CiJLvYcJBppGFi7crpbvlQv68M2hu05vhwL
 R/91H62X/5UaUlc1cJV63OBk8euWzF6XNbCQQrR4ayDvz+BsV5Fs72vYa1gx7qIt
 as/67oTT6y4U4pd74nT4OGkxDIXbXfn2eTbh5sMNc4ilBkqMyNbf8aOHdWqXZIBd
 18RKpNl6h/fiDMJ0jsGliReONLjfRBcJla68Kn1AFONMcyxcXidjptOwLOt2fYWf
 YMguCVMhfgxVBslzLWoQ9AWSiNVh36ycORWlCOrnRaOaQCb9OaLZ2fwibfZ0JsMd
 0259Z5vA7MIUoobCc5akXOYHbpByA9FSYkKudgTYLpdjkn05kxQyA12GgJjW3sVw
 ZRjoUuDuZDDUct6JcLWdrlONT8st05g+qf6PCoD+Jac8HtbpqHfKJJUtYecUat75
 4hGKhuvTzpuVY0wNHo3sgqKfsejQODTN6UhejNI11Zs/nx6O0ze/qoDuWZHncnKl
 158le+K5rNS8SUNbDBTMWp3OX4SJm/Gsf30fOWkkt6z1iaEfKc5sCxBHvSOeBEvH
 M9pzy56Vtw==
 =73nU
 -----END PGP SIGNATURE-----

Merge tag 'block-5.7-2020-05-09' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - a small series fixing a use-after-free of bdi name (Christoph,Yufen)

 - NVMe fix for a regression with the smaller CQ update (Alexey)

 - NVMe fix for a hang at namespace scanning error recovery (Sagi)

 - fix race with blk-iocost iocg->abs_vdebt updates (Tejun)

* tag 'block-5.7-2020-05-09' of git://git.kernel.dk/linux-block:
  nvme: fix possible hang when ns scanning fails during error recovery
  nvme-pci: fix "slimmer CQ head update"
  bdi: add a ->dev_name field to struct backing_dev_info
  bdi: use bdi_dev_name() to get device name
  bdi: move bdi_dev_name out of line
  vboxsf: don't use the source name in the bdi name
  iocost: protect iocg->abs_vdebt with iocg->waitq.lock
2020-05-10 11:16:07 -07:00
Linus Torvalds
e99332e7b4 gcc-10: mark more functions __init to avoid section mismatch warnings
It seems that for whatever reason, gcc-10 ends up not inlining a couple
of functions that used to be inlined before.  Even if they only have one
single callsite - it looks like gcc may have decided that the code was
unlikely, and not worth inlining.

The code generation difference is harmless, but caused a few new section
mismatch errors, since the (now no longer inlined) function wasn't in
the __init section, but called other init functions:

   Section mismatch in reference from the function kexec_free_initrd() to the function .init.text:free_initrd_mem()
   Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memremap()
   Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memunmap()

So add the appropriate __init annotation to make modpost not complain.
In both cases there were trivially just a single callsite from another
__init function.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 17:50:03 -07:00
Linus Torvalds
2e28f3b13a RISC-V Fixes for 5.7-rc5
This contains a smattering of fixes and cleanups that I'd like to target for
 5.7:
 
 * Dead code removal.
 * Exporting riscv_cpuid_to_hartid_mask for modules.
 * Per-CPU tracking of ISA features.
 * Setting max_pfn correctly when probing memory.
 * Adding a note to the VDSO so glibc can check the kernel's version without a
   uname().
 * A fix to force the bootloader to initialize the boot spin tables, which still
   get used as a fallback when SBI-0.1 is enabled.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAl61prsTHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRAuExnzX7sYia2UD/44ILoaQySVnLZ+ZzXaMXn3WwGHe8bS
 NVPQJB21ejkfbM8cDR5A8+w45FBrHquIRwhHnVkl5JU2AtvcdWh3tztmFx6Ejsu9
 FFBzcbHcXnYthkm1xLVPQASY0Pl6VOPdx47Mip9gvoLK79VetjQWNzUpFk4CBJdw
 nObgYgxE9twCQ7JOcK0VnPL9IpJ6E/lCcIyCi11NL9xRWtUyWk4hcmAFj/+tUegm
 DroT7QzKKxFS24eLaRkJgQGwAJ1jb0/b0ztl04U8NTOqVjgFXkGTC1Kuzd06Ch2U
 U34CYRL+A2sXwWnnNsIyjD7Epdalc/xx+JMEuD8dhnr0YK8WilvvG53gGwCwFgVc
 wpFhvsIuINYTw253Rv0q1oeRcDmMCKmV7bhOKSX4x0V1iGM1ognl/6zkCY4J0dQC
 7BCoeAGlpBTNbidatZ6jl5e32jes50ZRjhf3LxXe3mgrBd+diKXyOyLT01SVwqv/
 A1Sur/KquwoqT4RSx2Cel8JswPhfErhB0otL3CYoao8V7rxYGTKWKXg5SFAgwDHZ
 rib1UpYmyh2tjmoXb99ctlBpRHsYcVzXOZS9tG7B2ue7YhEwiZdV3249uwitAQgm
 NmGCH7tDe/nu5DLBoFyTjBJ64pZyn3YmE58M/uCmbXyMRVSGp2TXK83u3mfiw+gh
 kKNSRHJDAAl7Fg==
 =bGU8
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:
 "A smattering of fixes and cleanups:

   - Dead code removal.

   - Exporting riscv_cpuid_to_hartid_mask for modules.

   - Per-CPU tracking of ISA features.

   - Setting max_pfn correctly when probing memory.

   - Adding a note to the VDSO so glibc can check the kernel's version
     without a uname().

   - A fix to force the bootloader to initialize the boot spin tables,
     which still get used as a fallback when SBI-0.1 is enabled"

* tag 'riscv-for-linus-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  RISC-V: Remove unused code from STRICT_KERNEL_RWX
  riscv: force __cpu_up_ variables to put in data section
  riscv: add Linux note to vdso
  riscv: set max_pfn to the PFN of the last page
  RISC-V: Remove N-extension related defines
  RISC-V: Add bitmap reprensenting ISA features common across CPUs
  RISC-V: Export riscv_cpuid_to_hartid_mask() API
2020-05-09 16:24:16 -07:00
Linus Torvalds
1a263ae60b gcc-10: avoid shadowing standard library 'free()' in crypto
gcc-10 has started warning about conflicting types for a few new
built-in functions, particularly 'free()'.

This results in warnings like:

   crypto/xts.c:325:13: warning: conflicting types for built-in function ‘free’; expected ‘void(void *)’ [-Wbuiltin-declaration-mismatch]

because the crypto layer had its local freeing functions called
'free()'.

Gcc-10 is in the wrong here, since that function is marked 'static', and
thus there is no chance of confusion with any standard library function
namespace.

But the simplest thing to do is to just use a different name here, and
avoid this gcc mis-feature.

[ Side note: gcc knowing about 'free()' is in itself not the
  mis-feature: the semantics of 'free()' are special enough that a
  compiler can validly do special things when seeing it.

  So the mis-feature here is that gcc thinks that 'free()' is some
  restricted name, and you can't shadow it as a local static function.

  Making the special 'free()' semantics be a function attribute rather
  than tied to the name would be the much better model ]

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 15:58:04 -07:00