kernel/git/stable/linux.git/tools/include/nolibc, branch master

tools/nolibc: add support for Alpha

2026-08-02T07:30:55+00:00

A straightforward new architecture. Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Tested-by: Michael Cree Link: https://patch.msgid.link/20260722-nolibc-alpha-v2-1-4970e48eb7bf@weissschuh.net

tools/nolibc/powerpc: mark ctr and xer as clobbered by system call

2026-07-30T10:44:07+00:00

The system call can clobber the ctr and xer registers. Make sure the compiler takes this into account. The missing clobbers only seem to be an issue with newer compilers. Fixes: 0cb0675ec37e ("tools/nolibc: add support for powerpc") Signed-off-by: Thomas Weißschuh Link: https://patch.msgid.link/20260727-nolibc-powerpc-clobber-v1-1-e0911cc99ce1@linutronix.de Signed-off-by: Thomas Weißschuh

tools/nolibc: remove dead __ARCH_WANT_SYS_OLD_SELECT

2026-07-26T19:51:33+00:00

The macro lost its last user when select() was reimplemented on top of pselect6 for every architecture; sys/select.h no longer looks at it, and nothing else in the tree does either. See commit 668e43737279 ("tools/nolibc/select: drop non-pselect based implementations"). The comment that goes with it is stale for the same reason, as neither architecture can end up calling old_select any more. Drop both from arch-x86.h and arch-arm.h. Cc: Alviro Iskandar Setiawan Signed-off-by: Ammar Faizi Signed-off-by: Thomas Weißschuh

tools/nolibc: mark arg1 operand in __nolibc_syscall0() as write-only

2026-07-03T18:00:09+00:00

__nolibc_syscall0() does not set the arg1 variable before passing it to the asm block. This uninitialized variable read is undefined behavior. Clang can miscompile this. Mark the asm operand as write-only to fix this. Fixes: 8e1930296f92 ("tools/nolibc: Add support for SPARC") Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Link: https://patch.msgid.link/20260703-nolibc-sparc-asm-v1-1-c7fe73e2e777@weissschuh.net

tools/nolibc: unistd: Add readlink()

2026-07-03T06:07:59+00:00

Add readlink(). This is needed to test getcwd(). Signed-off-by: Daniel Palmer Acked-by: Willy Tarreau Link: https://patch.msgid.link/20260702085101.3304547-3-daniel@thingy.jp Signed-off-by: Thomas Weißschuh

tools/nolibc: unistd: Add getcwd()

2026-07-03T06:07:59+00:00

Add getcwd() for getting the current working directory. The behaviour matches what musl is doing except for one important difference: If the passed buf is NULL musl (and glibc) uses a big buffer on the stack and that is then strdup()'d and returned. According to the man page for getcwd() this is a glibc extension and I don't think we need it in nolibc. Signed-off-by: Daniel Palmer Acked-by: Willy Tarreau Link: https://patch.msgid.link/20260702085101.3304547-2-daniel@thingy.jp Signed-off-by: Thomas Weißschuh

tools/nolibc: cast default values of program_invocation_name

2026-05-26T19:06:12+00:00

With -Wwrite-strings the plain assignment triggers a warning as a 'const char *' is assigned to a 'char *', removing the const qualifier. Casting the const away is fine, as there is no valid modification that can be done to an empty string anyways. Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Link: https://patch.msgid.link/20260525-nolibc-write-strings-v2-1-ab5cc16c7b23@weissschuh.net

tools/nolibc: add ftruncate()

2026-05-24T21:58:04+00:00

On architectures with 32-bit longs, call the compat syscall __NR_ftruncate64. As off_t is 64-bit it must be split into 2 registers. Unlike llseek() which passes the high and low parts in explicitly named arguments, the order here is endian independent. Some architectures (arm, mips, ppc) require this pair of registers to be aligned to an even register, so add custom _sys_ftruncate64() wrappers for those. A test case for ftruncate is added which validates negative length or invalid fd return the appropriate error, and checks the length is correct on success. Co-developed-by: Jordan Richards Signed-off-by: Jordan Richards Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Reviewed-by: Daniel Palmer Link: https://patch.msgid.link/20260521-nolibc-ftruncate-v1-3-5384a83b2402@weissschuh.net

tools/nolibc: add a helper to split a 64-bit argument into 32-bit halves

2026-05-24T21:57:59+00:00

On 32-bit architectures some system calls require a single 64-bit argument to be passed as two 32-bit halves. Add a helper to easily split such arguments. This works on little and bit endian. Signed-off-by: Daniel Palmer Acked-by: Willy Tarreau Link: https://patch.msgid.link/20260521-nolibc-ftruncate-v1-2-5384a83b2402@weissschuh.net Signed-off-by: Thomas Weißschuh

tools/nolibc: stackprotector: Avoid stalling program startup if crng is not init yet

2026-05-24T21:52:58+00:00

We are using the getrandom syscall to get a random seed for the stack protector canary but we are calling it with no flags which means it'll block until there is some real randomness to return. This means that if the crng is not ready yet program startup will block and if you are unlucky that could be for a long time and look like the program has crashed. Even if the call to getrandom does not yield any random data, we will still initialize the canary. Fixes: 7188d4637e95 ("tools/nolibc: add support for stack protector") Signed-off-by: Daniel Palmer Acked-by: Willy Tarreau Link: https://patch.msgid.link/20260522090726.726985-1-daniel@thingy.jp Signed-off-by: Thomas Weißschuh