36554 Commits

Author SHA1 Message Date
Zhangjin Wu
418c846821 selftests/nolibc: libc-test: use HOSTCC instead of CC
libc-test is mainly added to compare the behavior of nolibc to the
system libc, it is meaningless and error-prone with cross compiling.

Let's use HOSTCC instead of CC to avoid wrongly use cross compiler when
CROSS_COMPILE is passed or customized.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Fixes: cfb672f94f6e ("selftests/nolibc: add run-libc-test target")
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:18:50 +02:00
Zhangjin Wu
dcb677c3d3 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>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
ce1bb82b1c selftests/nolibc: allow report with existing test log
After the tests finish, it is valuable to report and summarize with
existing test log.

This avoid rerun or run the tests again when not necessary.

Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
faeb4e09fe selftests/nolibc: add test support for ppc64
Kernel uses ARCH=powerpc for both 32-bit and 64-bit PowerPC, here adds a
ppc64 variant for big endian 64-bit PowerPC, users can pass XARCH=ppc64
to test it.

The powernv machine of qemu-system-ppc64 is used with
powernv_be_defconfig.

As the document [1] shows:

  PowerNV (as Non-Virtualized) is the “bare metal” platform using the
  OPAL firmware. It runs Linux on IBM and OpenPOWER systems and it can be
  used as an hypervisor OS, running KVM guests, or simply as a host OS.

Notes,

- differs from little endian 64-bit PowerPC, vmlinux is used instead of
  zImage, because big endian zImage [2] only boot on qemu with x-vof=on
  (added from qemu v7.0) and a fixup patch [3] for qemu v7.0.51:

- since the VSX support may be disabled in kernel side, to avoid
  "illegal instruction" errors due to missing VSX kernel support, let's
  simply let compiler not generate vector/scalar (VSX) instructions via
  the '-mno-vsx' option.

- as 'man gcc' shows, '-mmultiple' is used to generate code that uses
  the load multiple word instructions and the store multiple word
  instructions. Those instructions do not work when the processor is in
  little-endian mode (except PPC740/PPC750), so, we only enable it
  for big endian powerpc.

- for big endian ppc64, as the help message from arch/powerpc/Kconfig
  shows, the V2 ABI is standard for 64-bit little-endian, but for
  big-endian it is less well tested by kernel and toolchain, so, use
  elfv1 as-is, no need to explicitly ask toolchain to use elfv2 here.

[1]: https://qemu.readthedocs.io/en/latest/system/ppc/powernv.html
[2]: https://github.com/linuxppc/issues/issues/402
[3]: https://lore.kernel.org/qemu-devel/20220504065536.3534488-1-aik@ozlabs.ru/

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230722121019.GD17311@1wt.eu/
Link: https://lore.kernel.org/lkml/20230719043353.GC5331@1wt.eu/
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
8a5040cb3f selftests/nolibc: add test support for ppc64le
Kernel uses ARCH=powerpc for both 32-bit and 64-bit PowerPC, here adds a
ppc64le variant for little endian 64-bit PowerPC, users can pass
XARCH=ppc64le to test it.

The powernv machine of qemu-system-ppc64le is used for there is just a
working powernv_defconfig.

As the document [1] shows:

  PowerNV (as Non-Virtualized) is the “bare metal” platform using the
  OPAL firmware. It runs Linux on IBM and OpenPOWER systems and it can be
  used as an hypervisor OS, running KVM guests, or simply as a host OS.

Notes,

- since the VSX support may be disabled in kernel side, to avoid
  "illegal instruction" errors due to missing VSX kernel support, let's
  simply let compiler not generate vector/scalar (VSX) instructions via
  the '-mno-vsx' option.

- little endian ppc64 prefers elfv2 to elfv1 if the toolchain (e.g. gcc
  13.1.0) supports it, let's align with kernel, otherwise, our elfv1
  binary will not run on kernel with elfv2 ABI.

[1]: https://qemu.readthedocs.io/en/latest/system/ppc/powernv.html

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230722120747.GC17311@1wt.eu/
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
587e984591 selftests/nolibc: add test support for ppc
Kernel uses ARCH=powerpc for both 32-bit and 64-bit PowerPC, here adds a
ppc variant for 32-bit PowerPC and uses it as the default variant of
powerpc architecture.

Users can pass XARCH=ppc (or ARCH=powerpc) to test 32-bit PowerPC.

The default qemu-system-ppc g3beige machine [1] is used to run 32-bit
powerpc kernel with pmac32_defconfig. The missing PMACZILOG serial tty
and console are enabled in another patch [2].

Note,

- zImage doesn't boot due to "qemu-system-ppc: Some ROM regions are
  overlapping" error, so, vmlinux is used instead.

- since the VSX support may be disabled in kernel side, to avoid
  "illegal instruction" errors due to missing VSX kernel support, let's
  simply let compiler not generate vector/scalar (VSX) instructions via
  the '-mno-vsx' option.

- as 'man gcc' shows, '-mmultiple' is used to generate code that uses
  the load multiple word instructions and the store multiple word
  instructions. Those instructions do not work when the processor is in
  little-endian mode (except PPC740/PPC750), so, we only enable it
  for big endian powerpc.

[1]: https://qemu.readthedocs.io/en/latest/system/ppc/powermac.html
[2]: https://lore.kernel.org/lkml/bb7b5f9958b3e3a20f6573ff7ce7c5dc566e7e32.1690982937.git.tanyuan@tinylab.org/

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/ZL9leVOI25S2+0+g@1wt.eu/
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
c6c3734fb6 selftests/nolibc: add XARCH and ARCH mapping support
Most of the CPU architectures have different variants, but kernel
usually only accepts parts of them via the ARCH variable, the others
should be customized via kernel config files.

To simplify testing, a new XARCH variable is added to extend the
kernel's ARCH with a few variants of the same architecture, and it is
used to customize variant specific variables, at last XARCH is converted
to the kernel's ARCH:

  e.g. make run XARCH=<one of the supported variants>
                | \
                |  `-> variant specific variables:
                |      IMAGE, DEFCONFIG, QEMU_ARCH, QEMU_ARGS, CFLAGS ...
                \
                 `---> kernel's ARCH

XARCH and ARCH are carefully mapped to allow users to pass architecture
variants via XARCH or pass architecture via ARCH from cmdline.

PowerPC is the first user and also a very good reference architecture of
this mapping, it has variants with different combinations of
32-bit/64-bit and bit endian/little endian.

To use this mapping, the other architectures can refer to PowerPC, If
the target architecture only has one variant, XARCH is simply an alias
of ARCH, no additional mapping required.

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230702171715.GD16233@1wt.eu/
Link: https://lore.kernel.org/lkml/20230730061801.GA7690@1wt.eu/
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
e45ce88e65 tools/nolibc: add support for powerpc64
This follows the 64-bit PowerPC ABI [1], refers to the slides: "A new
ABI for little-endian PowerPC64 Design & Implementation" [2] and the
musl code in arch/powerpc64/crt_arch.h.

First, stdu and clrrdi are used instead of stwu and clrrwi for
powerpc64.

Second, the stack frame size is increased to 32 bytes for powerpc64, 32
bytes is the minimal stack frame size supported described in [2].

Besides, the TOC pointer (GOT pointer) must be saved to r2.

This works on both little endian and big endian 64-bit PowerPC.

[1]: https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.pdf
[2]: https://www.llvm.org/devmtg/2014-04/PDFs/Talks/Euro-LLVM-2014-Weigand.pdf

Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
0cb0675ec3 tools/nolibc: add support for powerpc
Both syscall declarations and _start code definition are added for
powerpc to nolibc.

Like mips, powerpc uses a register (exactly, the summary overflow bit)
to record the error occurred, and uses another register to return the
value [1]. So, the return value of every syscall declaration must be
normalized to match the __sysret() helper, return -value when there is
an error, otheriwse, return value directly.

Glibc and musl use different methods to check the summary overflow bit,
glibc (sysdeps/unix/sysv/linux/powerpc/sysdep.h) saves the cr register
to r0 at first, and then check the summary overflow bit in cr0:

    mfcr r0
    r0 & (1 << 28) ? -r3 : r3

    -->

    10003c14:       7c 00 00 26     mfcr    r0
    10003c18:       74 09 10 00     andis.  r9,r0,4096
    10003c1c:       41 82 00 08     beq     0x10003c24
    10003c20:       7c 63 00 d0     neg     r3,r3

Musl (arch/powerpc/syscall_arch.h) directly checks the summary overflow
bit with the 'bns' instruction, it is smaller:

    /* no summary overflow bit means no error, return value directly */
    bns+ 1f
    /* otherwise, return negated value */
    neg r3, r3
    1:

    -->

    10000418:       40 a3 00 08     bns     0x10000420
    1000041c:       7c 63 00 d0     neg     r3,r3

Like musl, Linux (arch/powerpc/include/asm/vdso/gettimeofday.h) uses the
same method for do_syscall_2() too.

Here applies the second method to get smaller size.

[1]: https://man7.org/linux/man-pages/man2/syscall.2.html

Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
45f65f8d04 selftests/nolibc: enable compiler warnings
It will help the developers to avoid cruft and detect some bugs.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
711edef8f7 selftests/nolibc: don't strip nolibc-test
Binary size is not important for nolibc-test and some debugging
information is nice to have, so don't strip the binary during linking.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
9c5e490093 selftests/nolibc: prevent out of bounds access in expect_vfprintf
If read() fails and returns -1 (or returns garbage for some other
reason) buf would be accessed out of bounds.
Only use the return value of read() after it has been validated.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
37266a9ec7 selftests/nolibc: use correct return type for read() and write()
Avoid truncating values before comparing them.

As printf in nolibc doesn't support ssize_t add casts to int for
printing.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
711f91fdec selftests/nolibc: avoid sign-compare warnings
These warnings will be enabled later so avoid triggering them.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
c8d078153f selftests/nolibc: avoid unused parameter warnings
This warning will be enabled later so avoid triggering it.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
17e66f235e selftests/nolibc: make functions static if possible
This allows the compiler to generate warnings if they go unused.

Functions that are supposed to be used as breakpoints should not be
static, so un-statify those if necessary.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
10874f20ee selftests/nolibc: mark test helpers as potentially unused
When warning about unused functions these would be reported by we want
to keep them for future use.

Suggested-by: Zhangjin Wu <falcon@tinylab.org>
Link: https://lore.kernel.org/lkml/20230731064826.16584-1-falcon@tinylab.org/
Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230731224929.GA18296@1wt.eu/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
79df81aaea selftests/nolibc: drop unused variables
These got copied around as new testcases where created.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Willy Tarreau
ca283457b3 selftests/nolibc: avoid warnings during intptr tests
Recent fix ceb528feb7c8 ("selftests/nolibc: avoid gaps in test numbers")
had the annoying side effect of always returning skipped tests, which
are normally supposed to happen only when certain features are missing
to run the test (missing kernel options, toolchain not supporting
stack-protector etc). As such there are now always warnings. Let's
modify the test to not use the condition and instead use a ternary
expression to check the result.

Fixes: ceb528feb7c8 ("selftests/nolibc: avoid gaps in test numbers")
Cc: Thomas WeiÃ<9F>schuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:57 +02:00
Thomas Weißschuh
202a0bd12f tools/nolibc: stdint: use __SIZE_TYPE__ for size_t
Otherwise both gcc and clang may generate warnings about type
mismatches:

sysroot/mips/include/string.h:12:14: warning: mismatch in argument 1 type of built-in function 'malloc'; expected 'unsigned int' [-Wbuiltin-declaration-mismatch]
   12 | static void *malloc(size_t len);
      |              ^~~~~~

The compiler provides __SIZE_TYPE__ as the type that corresponds to size_t
(typically "long unsigned int" or "unsigned int"). It was verified to be
available at least since gcc-3.4 and clang-3.8, so from now on we'll use
this definition for size_t.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/20230805161929.GA15284@1wt.eu/
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
04694658ad tools/nolibc: sys: avoid implicit sign cast
getauxval() returns an unsigned long but the overall type of the ternary
operator needs to be signed.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
809145f842 tools/nolibc: setvbuf: avoid unused parameter warnings
This warning will be enabled later so avoid triggering it.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
6407750225 tools/nolibc: fix return type of getpagesize()
It's documented as returning int which is also implemented by glibc and
musl, so adopt that return type.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
f2f5eaefa1 tools/nolibc: drop unused variables
Nobody needs it, get rid of it.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Yuan Tan
5c01259b12 selftests/nolibc: add testcase for pipe
Add a test case of pipe that sends and receives message in a single
process.

Suggested-by: Thomas Weißschuh <thomas@t-8ch.de>
Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/all/c5de2d13-3752-4e1b-90d9-f58cca99c702@t-8ch.de/
Signed-off-by: Yuan Tan <tanyuan@tinylab.org>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
[wt: fixed the "len" type to size_t to address a sign-compare warning
 with upcoming patches]
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Yuan Tan
3ec38af6ee tools/nolibc: add pipe() and pipe2() support
According to manual page [1], posix spec [2] and source code like
arch/mips/kernel/syscall.c, for historic reasons, the sys_pipe() syscall
on some architectures has an unusual calling convention.  It returns
results in two registers which means there is no need for it to do
verify the validity of a userspace pointer argument.  Historically that
used to be expensive in Linux.  These days the performance advantage is
negligible.

Nolibc doesn't support the unusual calling convention above, luckily
Linux provides a generic sys_pipe2() with an additional flags argument
from 2.6.27. If flags is 0, then pipe2() is the same as pipe(). So here
we use sys_pipe2() to implement the pipe().

pipe2() is also provided to allow users to use flags argument on demand.

[1]: https://man7.org/linux/man-pages/man2/pipe.2.html
[2]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/pipe.html

Suggested-by: Zhangjin Wu <falcon@tinylab.org>
Link: https://lore.kernel.org/all/20230729100401.GA4577@1wt.eu/
Signed-off-by: Yuan Tan <tanyuan@tinylab.org>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Zhangjin Wu
e7d0129df6 selftests/nolibc: mmap_munmap_good: fix up return value
The other tests use 1 as failure, mmap_munmap_good uses -1 as failure,
let's fix up this.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Thomas Weißschuh
447e56023f selftests/nolibc: avoid buffer underrun in space printing
If the test description is longer than the status alignment the
parameter 'n' to putcharn() would lead to a signed underflow that then
gets converted to a very large unsigned value.
This in turn leads out-of-bound writes in memset() crashing the
application.

The failure case of EXPECT_PTRER() used in "mmap_bad" exhibits this
exact behavior.

Fixes: 29f5540be392 ("selftests/nolibc: add EXPECT_PTREQ, EXPECT_PTRNE and EXPECT_PTRER")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 05:17:07 +02:00
Ryan Roberts
4893c22eb2 tools/nolibc/stdio: add setvbuf() to set buffering mode
Add a minimal implementation of setvbuf(), which error checks the mode
argument (as required by spec) and returns. Since nolibc never buffers
output, nothing needs to be done.

The kselftest framework recently added a call to setvbuf(). As a result,
any tests that use the kselftest framework and nolibc cause a compiler
error due to missing function. This provides an urgent fix for the
problem which is preventing arm64 testing on linux-next.

Example:

clang --target=aarch64-linux-gnu -fintegrated-as
-Werror=unknown-warning-option -Werror=ignored-optimization-argument
-Werror=option-ignored -Werror=unused-command-line-argument
--target=aarch64-linux-gnu -fintegrated-as
-fno-asynchronous-unwind-tables -fno-ident -s -Os -nostdlib \
-include ../../../../include/nolibc/nolibc.h -I../..\
-static -ffreestanding -Wall za-fork.c
build/kselftest/arm64/fp/za-fork-asm.o
-o build/kselftest/arm64/fp/za-fork
In file included from <built-in>:1:
In file included from ./../../../../include/nolibc/nolibc.h:97:
In file included from ./../../../../include/nolibc/arch.h:25:
./../../../../include/nolibc/arch-aarch64.h:178:35: warning: unknown
attribute 'optimize' ignored [-Wunknown-attributes]
void __attribute__((weak,noreturn,optimize("omit-frame-pointer")))
__no_stack_protector _start(void)
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from za-fork.c:12:
../../kselftest.h:123:2: error: call to undeclared function 'setvbuf';
ISO C99 and later do not support implicit function declarations
[-Wimplicit-function-declaration]
        setvbuf(stdout, NULL, _IOLBF, 0);
        ^
../../kselftest.h:123:24: error: use of undeclared identifier '_IOLBF'
        setvbuf(stdout, NULL, _IOLBF, 0);
                              ^
1 warning and 2 errors generated.

Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Link: https://lore.kernel.org/linux-kselftest/CA+G9fYus3Z8r2cg3zLv8uH8MRrzLFVWdnor02SNr=rCz+_WGVg@mail.gmail.com/
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
850fad7de8 selftests/nolibc: allow test -include /path/to/nolibc.h
As the head comment of nolibc-test.c shows, it can be built in 3 ways:

    $(CC) -nostdlib -include /path/to/nolibc.h => NOLIBC already defined
    $(CC) -nostdlib -I/path/to/nolibc/sysroot  => _NOLIBC_* guards are present
    $(CC) with default libc                    => NOLIBC* never defined

Only last two of them are tested currently, let's allow test the first one too.

This may help to find issues about using nolibc.h to build programs. it
derives from this change:

    commit 3a8039e289a3 ("tools/nolibc: Fix build of stdio.h due to header ordering")

Usage:

    // test with sysroot by default
    $ make run-user

    // test without sysroot, using nolibc.h directly
    $ make run-user NOLIBC_SYSROOT=0

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
b81434073b selftests/nolibc: allow run nolibc-test locally
It is able to run nolibc-test directly without qemu-user when the target
machine is the same as the host machine.

Sometimes, the result running locally may help a lot when the qemu-user
package is too old.

When the target machine differs from the host machine, it is also able
to run nolibc-test directly with qemu-user-static + binfmt_misc.

Link: https://lore.kernel.org/lkml/ZKutZwIOfy5MqedG@1wt.eu/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
48967b73f8 selftests/nolibc: add testcases for startup code
The startup code is critical to get the right argc, argv, envp/environ
and _auxv, let's add a startup test group and the corresponding
testcases.

The "environ" test case is also moved from the stdlib test group to this
new startup test group and it is renamed to "environ_envp".

Since argv0 has been used by many other test cases, let's add testcases
to gurantee it too.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
fd3a9efde8 selftests/nolibc: add EXPECT_PTRGE, EXPECT_PTRGT, EXPECT_PTRLE, EXPECT_PTRLT
4 new pointer compare macros are added, they are similar to the integer
compare macros.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
c48d8af2fa tools/nolibc: s390: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
eea70cdac6 tools/nolibc: riscv: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
61bd4621c0 tools/nolibc: loongarch: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
431b806b9b tools/nolibc: mips: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Also clean up the instructions in delayed slots.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
539287d751 tools/nolibc: x86_64: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
2ab446336b tools/nolibc: i386: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
ded8af47c2 tools/nolibc: aarch64: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
61f9880721 tools/nolibc: arm: shrink _start with _start_c
move most of the _start operations to _start_c(), include the
stackprotector initialization.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
06f2a62c81 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>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
d7f16723d3 tools/nolibc: stackprotector.h: add empty __stack_chk_init for !_NOLIBC_STACKPROTECTOR
Let's define an empty __stack_chk_init for the !_NOLIBC_STACKPROTECTOR
branch.

This allows to remove #ifdef around every call of __stack_chk_init().

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
1733675515 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>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
af93807eae tools/nolibc: remove the old sys_stat support
The statx manpage [1] shows that it has been supported from Linux 4.11
and glibc 2.28, the Linux support can be checked for all of the
architectures with this command:

    $ git grep -r statx v4.11 arch/ include/uapi/asm-generic/unistd.h \
      | grep -E "aarch64|arm|mips|s390|x86|:include/uapi"

Besides riscv and loongarch, all of the nolibc supported architectures
have added sys_statx from Linux v4.11. riscv is mainlined to v4.15,
loongarch is mainlined to v5.19, both of them use the generic unistd.h,
so, they have added sys_statx from their first mainline versions.

The current oldest stable branch is v4.14, only reserving sys_statx
still preserves compatibility with all of the supported stable branches,
So, let's remove the old arch related and dependent sys_stat support
completely.

This is friendly to the future new architecture porting.

[1]: https://man7.org/linux/man-pages/man2/statx.2.html

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
bff60150f7 tools/nolibc: fix up startup failures for -O0 under gcc < 11.1.0
As gcc doc [1] shows:

  Most optimizations are completely disabled at -O0 or if an -O level is
  not set on the command line, even if individual optimization flags are
  specified.

Test result [2] shows, gcc>=11.1.0 deviates from the above description,
but before gcc 11.1.0, "-O0" still forcely uses frame pointer in the
_start function even if the individual optimize("omit-frame-pointer")
flag is specified.

The frame pointer related operations will change the stack pointer (e.g.
In x86_64, an extra "push %rbp" will be inserted at the beginning of
_start) and make it differs from the one we expected, as a result, break
the whole startup function.

To fix up this issue, as suggested by Thomas, the individual "Os" and
"omit-frame-pointer" optimize flags are used together on _start function
to disable frame pointer completely even if the -O0 is set on the
command line.

[1]: https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html
[2]: https://lore.kernel.org/lkml/20230714094723.140603-1-falcon@tinylab.org/

Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/34b21ba5-7b59-4b3b-9ed6-ef9a3a5e06f7@t-8ch.de/
Fixes: 7f8548589661 ("tools/nolibc: make compiler and assembler agree on the section around _start")
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Zhangjin Wu
2023349835 tools/nolibc: arch-*.h: add missing space after ','
Fix up such errors reported by scripts/checkpatch.pl:

    ERROR: space required after that ',' (ctx:VxV)
    #148: FILE: tools/include/nolibc/arch-aarch64.h:148:
    +void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
                             ^

    ERROR: space required after that ',' (ctx:VxV)
    #148: FILE: tools/include/nolibc/arch-aarch64.h:148:
    +void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
                                      ^

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Thomas Weißschuh
ceb528feb7 selftests/nolibc: avoid gaps in test numbers
As the test numbers are based on line numbers gaps without testcases are
to be avoided.
Instead use the already existing test condition logic to implement
conditional execution.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Thomas Weißschuh
b184a261e5 selftests/nolibc: simplify status printing
pad_spc() is only ever used to print the status message of testcases.
The line size is always constant, the return value is never used and the
format string is never used as such.

Remove all the unneeded logic and simplify the API and its users.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00
Thomas Weißschuh
3097783ecf selftests/nolibc: make evaluation of test conditions
If "cond" is a multi-token statement the behavior of the preprocessor
will lead to the negation "!" to be only applied to the first token.
Although currently no test uses such multi-token conditions but it can
happen at any time.

Put braces around "cond" to ensure the negation works as expected.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2023-08-23 04:40:22 +02:00