The arm64 ABI selftests fail to compile due to missing include paths
for kernel headers, causing errors like incomplete type struct sock_filter
and implicit BPF macro declarations.

Add $(KHDR_INCLUDES) and -I$(top_srcdir)/tools/include to CFLAGS
to resolve the header search path. Also remove the hardcoded __NR_write
macro and include <asm/unistd.h> to obtain the correct syscall number.

Fixes: 21e37da12071 ("kselftest/arm64: Add testcase for SECCOMP_RET_TRACE orig_x0 bypass")
Fixes: 2fcbc4adf997 ("kselftest/arm64: Add seccomp ptrace x0 bypass test")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/r/202608021842.jp6IBrFi-lkp@intel.com/
Suggested-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>

Add a selftest that verifies the kernel re-evaluates a seccomp filter
with the correct (ptrace-modified) first argument after
a SECCOMP_RET_TRACE stop. On arm64, syscall_get_arguments() reads
the first argument from orig_x0, which may be stale if the tracer modified
regs->regs[0] but orig_x0 was not synced.  This can cause the filter to
see an old argument and incorrectly allow a syscall that it should
have rejected.

The child installs a filter that:
 - TRACEs write() when fd == 2
 - returns ERRNO(EPERM) when fd == 1

The parent catches the SECCOMP event, changes x0 (fd) from 2 to 1,
and resumes the child.

If the seccomp re-evaluation sees the stale orig_x0 (fd=2) the filter
returns TRACE again and the kernel (with recheck_after_trace=true)
allows the syscall to proceed – write succeeds and the child exits 0.
If the seccomp re-evaluation sees the new value (fd=1) the filter
returns ERRNO(EPERM), write fails and the child exits non-zero.
The test passes only when the write fails (child exit != 0).

Before the fix:
	# ./seccomp_ret_trace_x0_bypass
	TAP version 13
	1..1
	not ok 1 write succeeded, orig_x0 bypass likely
	# Totals: pass:0 fail:1 xfail:0 xpass:0 skip:0 error:0

After the fix:
	# ./seccomp_ret_trace_x0_bypass
	TAP version 13
	1..1
	ok 1 seccomp correctly denied modified syscall
	# Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0

Cc: Kees Cook <kees@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/all/20260717182758.17111-1-will@kernel.org/
Link: https://lore.kernel.org/all/20260716120640.6590-1-will@kernel.org/
Link: https://lore.kernel.org/all/202607152004.DEA95D63@keescook/
Suggested-by: Kees Cook <kees@kernel.org>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>

As Kees suggested, add a test that verifies that seccomp observes the
correct first argument after a ptracer modifies x0 at a syscall-enter-stop
on arm64.

The first syscall argument and the return value share register x0.
The original value is saved in orig_x0 on entry and used by
syscall_get_arguments(), but ptrace changes to x0 were not
automatically reflected there.  This test checks the kernel re-syncs
orig_x0 after a ptrace stop so that seccomp sees the modified
argument.

A seccomp filter allows write(2,...) and kills the task for any other
fd.  The tracer changes fd from 2 to 1 at entry.  If orig_x0 remains
stale, the child exits normally (bypass, test fails).  If orig_x0 is
correctly updated, the child is killed by SIGSYS (test passes).

Before the fix:
	 ./seccomp_ptrace_x0_bypass
	TAP version 13
	1..1
	not ok 1 seccomp_ptrace_x0_bypass
	# Totals: pass:0 fail:1 xfail:0 xpass:0 skip:0 error:0

After the fix:
	# ./seccomp_ptrace_x0_bypass
	TAP version 13
	1..1
	[   19.475951] audit: type=1326 audit(1784254846.284:2): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=227 comm="seccomp_ptrace_" exe="/mnt/seccomp0
	[   19.477852] audit: type=1701 audit(1784254846.284:3): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=227 comm="seccomp_ptrace_" exe="/mnt/seccomp1
	ok 1 seccomp_ptrace_x0_bypass
	# Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0

Cc: Kees Cook <kees@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/all/20260716120640.6590-1-will@kernel.org/
Link: https://lore.kernel.org/all/202607152004.DEA95D63@keescook/
Suggested-by: Kees Cook <kees@kernel.org>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>

Add coverage of the new hwcaps to the test program, encodings cross checked
against LLVM 22.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

The function executes a CBEQ instruction which is valid if the CPU
supports the CMPBR extension. The CBEQ branches to skip the following
UDF instruction, and no SIGILL is generated. Otherwise, it will
generate a SIGILL.

Signed-off-by: Yifan Wu <wuyifan50@huawei.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

The FEAT_SVE2p1 is indicated by ID_AA64ZFR0_EL1.SVEver. However,
the BFADD requires the FEAT_SVE_B16B16, which is indicated by
ID_AA64ZFR0_EL1.B16B16. This could cause the test to incorrectly
fail on a CPU that supports FEAT_SVE2.1 but not FEAT_SVE_B16B16.

LD1Q Gather load quadwords which is decoded from SVE encodings and
implied by FEAT_SVE2p1.

Fixes: c5195b027d29 ("kselftest/arm64: Add SVE 2.1 to hwcap test")
Signed-off-by: Yifan Wu <wuyifan50@huawei.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

Add tests for FEAT_LS64. Issue related instructions if feature
presents, no SIGILL should be received. When such instructions
operate on Device memory or non-cacheable memory, we may received
a SIGBUS during the test (w/o FEAT_LS64WB). Just ignore it since
we only tested whether the instruction itself can be issued as
expected on platforms declaring the support of such features.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Will Deacon <will@kernel.org>

The my_syscall*() macros are internal implementation details of nolibc.
Nolibc also provides the regular syscall(2), which is also a macro
and directly expands to the correct my_syscall().

Use syscall() instead.

As a side-effect this fixes some return value checks, as my_syscall()
returns the raw value as set by the kernel and does not set errno.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

This follow-up patch completes centralization of kselftest.h and
ksefltest_harness.h includes in remaining seltests files, replacing all
relative paths with a non-relative paths using shared -I include path in
lib.mk

Tested with gcc-13.3 and clang-18.1, and cross-compiled successfully on
riscv, arm64, x86_64 and powerpc arch.

[reddybalavignesh9979@gmail.com: add selftests include path for kselftest.h]
  Link: https://lkml.kernel.org/r/20251017090201.317521-1-reddybalavignesh9979@gmail.com
Link: https://lkml.kernel.org/r/20251016104409.68985-1-reddybalavignesh9979@gmail.com
Signed-off-by: Bala-Vignesh-Reddy <reddybalavignesh9979@gmail.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/lkml/20250820143954.33d95635e504e94df01930d0@linux-foundation.org/
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Günther Noack <gnoack@google.com>
Cc: Jakub Kacinski <kuba@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mickael Salaun <mic@digikod.net>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Simon Horman <horms@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Pull nolibc updates from Thomas Weißschuh:
 "Only small bugfixes and cleanups"

* tag 'nolibc-20250928-for-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/nolibc/linux-nolibc:
  tools/nolibc: add stdbool.h to nolibc includes
  tools/nolibc: make time_t robust if __kernel_old_time_t is missing in host headers
  selftests/nolibc: remove outdated comment about construct order
  selftests/nolibc: fix EXPECT_NZ macro
  tools/nolibc: drop wait4() support
  kselftest/arm64: tpidr2: Switch to waitpid() over wait4()
  tools/nolibc: fold llseek fallback into lseek()
  tools/nolibc: remove __nolibc_enosys() fallback from fork functions
  tools/nolibc: remove __nolibc_enosys() fallback from dup2()
  tools/nolibc: remove __nolibc_enosys() fallback from *at() functions
  tools/nolibc: remove __nolibc_enosys() fallback from time64-related functions
  tools/nolibc: use tabs instead of spaces for indentation
  tools/nolibc: avoid error in dup2() if old fd equals new fd
  selftests/nolibc: always compile the kernel with GCC
  selftests/nolibc: don't pass CC to toplevel Makefile
  selftests/nolibc: deduplicate invocations of toplevel Makefile
  selftests/nolibc: be more specific about variables affecting nolibc-test
  tools/nolibc: fix error return value of clock_nanosleep()