Merge tag 'urgent/nolibc.2023.10.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull nolibc fixes from Paul McKenney:

- tools/nolibc: i386: Fix a stack misalign bug on _st

Merge tag 'urgent/nolibc.2023.10.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull nolibc fixes from Paul McKenney:

- tools/nolibc: i386: Fix a stack misalign bug on _start

- MAINTAINERS: nolibc: update tree location

- tools/nolibc: mark start_c as weak to avoid linker errors

* tag 'urgent/nolibc.2023.10.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
tools/nolibc: mark start_c as weak
MAINTAINERS: nolibc: update tree location
tools/nolibc: i386: Fix a stack misalign bug on _start

show more ...

tools/nolibc: mark start_c as weak

Otherwise the different instances of _start_c from each compilation unit
will lead to linker errors:

/usr/bin/ld: /tmp/ccSNvRqs.o: in function `_start_c':
nolibc-

tools/nolibc: mark start_c as weak

Otherwise the different instances of _start_c from each compilation unit
will lead to linker errors:

/usr/bin/ld: /tmp/ccSNvRqs.o: in function `_start_c':
nolibc-test-foo.c:(.text.nolibc_memset+0x9): multiple definition of `_start_c'; /tmp/ccG25101.o:nolibc-test.c:(.text+0x1ea3): first defined here

Fixes: 17336755150b ("tools/nolibc: add new crt.h with _start_c")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/20231012-nolibc-start_c-multiple-v1-1-fbfc73e0283f@weissschuh.net/
Link: https://lore.kernel.org/lkml/20231012-nolibc-linkage-test-v1-1-315e682768b4@weissschuh.net/
Acked-by: Willy Tarreau <w@1wt.eu>

show more ...

Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'linux-kselftest-nolibc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull nolibc updates from Shuah Khan:
"Nolibc:
- improved portability by removing

Merge tag 'linux-kselftest-nolibc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull nolibc updates from Shuah Khan:
"Nolibc:
- improved portability by removing build errors with -ENOSYS
- added syscall6() on MIPS to support pselect6() and mmap()
- added setvbuf(), rmdir(), pipe(), pipe2()
- add support for ppc/ppc64
- environ is no longer optional
- fixed frame pointer issues at -O0
- dropped sys_stat() in favor of sys_statx()
- centralized _start_c() to remove lots of asm code
- switched size_t to __SIZE_TYPE__

Selftests:
- improved status reporting (success/warning/failure counts, path to
log file)
- various code cleanups (indent, unused variables, ...)
- more consistent test numbering
- enabled compiler warnings
- dropped unreliable chmod_net test
- improved reliability (create /dev/zero & /tmp, rely less on /proc)
- new tests (brk/sbrk/mmap/munmap)
- improved compatibility with musl
- new run-nolibc-test target to build and run natively
- new run-libc-test target to build and run against native libc
- made the cmdline parser more reliable against boolean arguments
- dropped dependency on memfd for vfprintf() test
- nolibc-test is no longer stripped
- added support for extending ARCH via XARCH

Other:
- add Thomas as co-maintainer"

* tag 'linux-kselftest-nolibc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (103 commits)
tools/nolibc: avoid undesired casts in the __sysret() macro
tools/nolibc: keep brk(), sbrk(), mmap() away from __sysret()
tools/nolibc: silence ppc64 compile warnings
selftests/nolibc: libc-test: use HOSTCC instead of CC
tools/nolibc: stackprotector.h: make __stack_chk_init static
selftests/nolibc: allow report with existing test log
selftests/nolibc: add test support for ppc64
selftests/nolibc: add test support for ppc64le
selftests/nolibc: add test support for ppc
selftests/nolibc: add XARCH and ARCH mapping support
tools/nolibc: add support for powerpc64
tools/nolibc: add support for powerpc
MAINTAINERS: nolibc: add myself as co-maintainer
selftests/nolibc: enable compiler warnings
selftests/nolibc: don't strip nolibc-test
selftests/nolibc: prevent out of bounds access in expect_vfprintf
selftests/nolibc: use correct return type for read() and write()
selftests/nolibc: avoid sign-compare warnings
selftests/nolibc: avoid unused parameter warnings
selftests/nolibc: make functions static if possible
...

show more ...

tools/nolibc: stackprotector.h: make __stack_chk_init static

This allows to generate smaller text/data/dec size.

As the _start_c() function added by crt.h, __stack_chk_init() is called
from _start_

tools/nolibc: stackprotector.h: make __stack_chk_init static

This allows to generate smaller text/data/dec size.

As the _start_c() function added by crt.h, __stack_chk_init() is called
from _start_c() instead of the assembly _start. So, it is able to mark
it with static now.

Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

show more ...

tools/nolibc: crt.h: initialize stack protector

As suggested by Thomas, It is able to move the stackprotector
initialization from the assembly _start to the beginning of the new
_start_c(). Let's ca

tools/nolibc: crt.h: initialize stack protector

As suggested by Thomas, It is able to move the stackprotector
initialization from the assembly _start to the beginning of the new
_start_c(). Let's call __stack_chk_init() in _start_c() as a
preparation.

Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/a00284a6-54b1-498c-92aa-44997fa78403@t-8ch.de/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

show more ...

tools/nolibc: add new crt.h with _start_c

As the environ and _auxv support added for nolibc, the assembly _start
function becomes more and more complex and therefore makes the porting
of nolibc to n

tools/nolibc: add new crt.h with _start_c

As the environ and _auxv support added for nolibc, the assembly _start
function becomes more and more complex and therefore makes the porting
of nolibc to new architectures harder and harder.

To simplify portability, this C version of _start_c() is added to do
most of the assembly start operations in C, which reduces the complexity
a lot and will eventually simplify the porting of nolibc to the new
architectures.

The new _start_c() only requires a stack pointer argument, it will find
argc, argv, envp/environ and _auxv for us, and then call main(),
finally, it exit() with main's return status. With this new _start_c(),
the future new architectures only require to add very few assembly
instructions.

As suggested by Thomas, users may use a different signature of main
(e.g. void main(void)), a _nolibc_main alias is added for main to
silence the warning about potential conflicting types.

As suggested by Willy, the code is carefully polished for both smaller
size and better readability with local variables and the right types.

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230715095729.GC24086@1wt.eu/
Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/90fdd255-32f4-4caf-90ff-06456b53dac3@t-8ch.de/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

show more ...