linux-stable/tools/testing/selftests/x86
Jun Miao a051b2e56f selftests/x86: Fix error: variably modified 'altstack_data' at file scope
A glibc 2.34 feature adds support for variable MINSIGSTKSZ and SIGSTKSZ.
When _DYNAMIC_STACK_SIZE_SOURCE or _GNU_SOURCE are defined, MINSIGSTKSZ
and SIGSTKSZ are no longer constant on Linux. glibc 2.34 flags code paths
assuming MINSIGSTKSZ or SIGSTKSZ are constant. Fix these error in x86 test.

Feature description and build error:

NEWS for version 2.34
=====================
Major new features:
 * Add _SC_MINSIGSTKSZ and _SC_SIGSTKSZ.  When _DYNAMIC_STACK_SIZE_SOURCE
   or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ are no longer
   constant on Linux.  MINSIGSTKSZ is redefined to sysconf(_SC_MINSIGSTKSZ)
   and SIGSTKSZ is redefined to sysconf (_SC_SIGSTKSZ).  This supports
   dynamic sized register sets for modern architectural features like
   Arm SVE.
=====================

If _SC_SIGSTKSZ_SOURCE or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ
are redefined as:

/* Default stack size for a signal handler: sysconf (SC_SIGSTKSZ).  */
 # undef SIGSTKSZ
 # define SIGSTKSZ sysconf (_SC_SIGSTKSZ)

/* Minimum stack size for a signal handler: SIGSTKSZ.  */
 # undef MINSIGSTKSZ
 # define MINSIGSTKSZ SIGSTKSZ

Compilation will fail if the source assumes constant MINSIGSTKSZ or
SIGSTKSZ.

Build error with the GNU C Library 2.34:
DEBUG:	| sigreturn.c:150:13: error: variably modified 'altstack_data' at file scope
| sigreturn.c:150:13: error: variably modified 'altstack_data' at file scope
DEBUG:	|   150 | static char altstack_data[SIGSTKSZ];
|   150 | static char altstack_data[SIGSTKSZ];
DEBUG:	|       |             ^~~~~~~~~~~~~

DEBUG:  | single_step_syscall.c:60:22: error: variably modified 'altstack_data' at file scope
DEBUG:  |   60 | static unsigned char altstack_data[SIGSTKSZ];
DEBUG:  |      |                      ^~~~~~~~~~~~~

Fixed commit log to improve formatting and clarity:
Shuah Khan <skhan@linuxfoundation.org>

Link: https://sourceware.org/pipermail/libc-alpha/2021-January/121996.html
Link: https://sourceware.org/pipermail/libc-alpha/2021-August/129718.html
Suggested-by: Jianwei Hu <jianwei.hu@windriver.com>
Signed-off-by: Jun Miao <jun.miao@windriver.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-08-25 16:54:39 -06:00
..
.gitignore selftests/x86/pkeys: move selftests to arch-neutral directory 2020-06-04 19:06:26 -07:00
check_cc.sh treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257 2019-06-05 17:30:27 +02:00
check_initial_reg_state.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
corrupt_xstate_header.c selftests/x86: Test signal frame XSTATE header corruption handling 2021-06-09 14:46:30 +02:00
entry_from_vm86.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257 2019-06-05 17:30:27 +02:00
fsgsbase.c selftests/x86/fsgsbase: Fix GS == 1, 2, and 3 tests 2020-11-24 13:46:16 +01:00
fsgsbase_restore.c x86/ptrace: Fix 32-bit PTRACE_SETREGS vs fsbase and gsbase 2020-07-01 15:27:20 +02:00
helpers.h selftests/x86: Use __builtin_ia32_read/writeeflags 2021-01-12 12:31:28 +01:00
ioperm.c selftests/x86/ioperm: Extend testing so the shared bitmap is exercised 2019-11-16 11:24:04 +01:00
iopl.c selftests/x86/iopl: Extend test to cover IOPL emulation 2019-11-16 11:24:06 +01:00
ldt_gdt.c selftests/x86/ldt_gdt: remove unneeded semicolon 2021-02-08 16:32:52 -07:00
Makefile selftests/x86: Test signal frame XSTATE header corruption handling 2021-06-09 14:46:30 +02:00
mov_ss_trap.c selftests/x86: Fix error: variably modified 'altstack_data' at file scope 2021-08-25 16:54:39 -06:00
ptrace_syscall.c selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault 2020-03-20 11:28:47 +01:00
raw_syscall_helper_32.S selftests/x86: Add missing .note.GNU-stack sections 2020-11-24 13:55:39 +01:00
sigaltstack.c selftest/x86/signal: Include test cases for validating sigaltstack 2021-05-19 12:45:07 +02:00
sigreturn.c selftests/x86: Fix error: variably modified 'altstack_data' at file scope 2021-08-25 16:54:39 -06:00
single_step_syscall.c selftests/x86: Fix error: variably modified 'altstack_data' at file scope 2021-08-25 16:54:39 -06:00
syscall_arg_fault.c selftests/x86: Fix error: variably modified 'altstack_data' at file scope 2021-08-25 16:54:39 -06:00
syscall_nt.c x86/entry, selftests: Further improve user entry sanity checks 2020-07-04 19:47:25 +02:00
syscall_numbering.c selftests/x86/syscall: Add tests under ptrace to syscall_numbering_64 2021-05-20 15:19:48 +02:00
sysret_rip.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
sysret_ss_attrs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
test_FCMOV.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test_FCOMI.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test_FISTTP.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
test_mremap_vdso.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
test_syscall_vdso.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
test_vsyscall.c selftests/x86/test_vsyscall: Improve the process_vm_readv() test 2020-09-03 18:36:55 -07:00
thunks.S selftests/x86: Add missing .note.GNU-stack sections 2020-11-24 13:55:39 +01:00
thunks_32.S selftests/x86: Add a missing .note.GNU-stack section to thunks_32.S 2021-03-18 11:05:14 +01:00
trivial_32bit_program.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257 2019-06-05 17:30:27 +02:00
trivial_64bit_program.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 257 2019-06-05 17:30:27 +02:00
trivial_program.c selftests/x86: Detect -no-pie availability 2018-05-30 15:21:51 -06:00
unwind_vdso.c selftests/x86: Consolidate and fix get/set_eflags() helpers 2020-07-01 10:00:27 +02:00
vdso_restorer.c selftests/x86/vdso: Fix no-vDSO segfaults 2020-03-20 11:20:04 +01:00