kernel/linux.git/tools/testing/selftests/vDSO, branch v5.10.257

powerpc/vdso: Flag VDSO64 entry points as functions

2024-12-14T18:47:57+00:00

[ Upstream commit 0161bd38c24312853ed5ae9a425a1c41c4ac674a ] On powerpc64 as shown below by readelf, vDSO functions symbols have type NOTYPE. $ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg ELF Header: Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 Class: ELF64 Data: 2's complement, big endian Version: 1 (current) OS/ABI: UNIX - System V ABI Version: 0 Type: DYN (Shared object file) Machine: PowerPC64 Version: 0x1 ... Symbol table '.dynsym' contains 12 entries: Num: Value Size Type Bind Vis Ndx Name ... 1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 ... 4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 Symbol table '.symtab' contains 56 entries: Num: Value Size Type Bind Vis Ndx Name ... 45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu 47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64") was applied to have selftests also look for NOTYPE symbols, but the correct fix should be to flag VDSO entry points as functions. The original commit that brought VDSO support into powerpc/64 has the following explanation: Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps can't be expected to link against them directly, the vDSO's are both seen as if they were linked at 0 and the symbols just contain offsets to the various functions. This is done on purpose to avoid a relocation step (ppc64 functions normally have descriptors with abs addresses in them). When glibc uses those functions, it's expected to use it's own trampolines that know how to reach them. The descriptors it's talking about are the OPD function descriptors used on ABI v1 (big endian). But it would be more correct for a text symbol to have type function, even if there's no function descriptor for it. glibc has a special case already for handling the VDSO symbols which creates a fake opd pointing at the kernel symbol. So changing the VDSO symbol type to function shouldn't affect that. For ABI v2, there is no function descriptors and VDSO functions can safely have function type. So lets flag VDSO entry points as functions and revert the selftest change. Link: https://github.com/mpe/linux-fullhistory/commit/5f2dd691b62da9d9cc54b938f8b29c22c93cb805 Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64") Signed-off-by: Christophe Leroy Reviewed-By: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin

selftests: vDSO: fix vDSO symbols lookup for powerpc64

2024-10-17T13:08:17+00:00

[ Upstream commit ba83b3239e657469709d15dcea5f9b65bf9dbf34 ] On powerpc64, following tests fail locating vDSO functions: ~ # ./vdso_test_abi TAP version 13 1..16 # [vDSO kselftest] VDSO_VERSION: LINUX_2.6.15 # Couldn't find __kernel_gettimeofday ok 1 # SKIP __kernel_gettimeofday # clock_id: CLOCK_REALTIME # Couldn't find __kernel_clock_gettime ok 2 # SKIP __kernel_clock_gettime CLOCK_REALTIME # Couldn't find __kernel_clock_getres ok 3 # SKIP __kernel_clock_getres CLOCK_REALTIME ... # Couldn't find __kernel_time ok 16 # SKIP __kernel_time # Totals: pass:0 fail:0 xfail:0 xpass:0 skip:16 error:0 ~ # ./vdso_test_getrandom __kernel_getrandom is missing! ~ # ./vdso_test_gettimeofday Could not find __kernel_gettimeofday ~ # ./vdso_test_getcpu Could not find __kernel_getcpu On powerpc64, as shown below by readelf, vDSO functions symbols have type NOTYPE, so also accept that type when looking for symbols. $ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg ELF Header: Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 Class: ELF64 Data: 2's complement, big endian Version: 1 (current) OS/ABI: UNIX - System V ABI Version: 0 Type: DYN (Shared object file) Machine: PowerPC64 Version: 0x1 ... Symbol table '.dynsym' contains 12 entries: Num: Value Size Type Bind Vis Ndx Name 0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND 1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 2: 00000000000005f0 36 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 3: 0000000000000578 68 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 6: 0000000000000614 172 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 7: 00000000000006f0 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 8: 000000000000047c 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 9: 0000000000000454 12 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 10: 00000000000004d0 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 11: 00000000000005bc 52 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 Symbol table '.symtab' contains 56 entries: Num: Value Size Type Bind Vis Ndx Name ... 45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu 47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres 48: 00000000000005f0 36 NOTYPE GLOBAL DEFAULT 8 __kernel_get_tbfreq 49: 000000000000047c 84 NOTYPE GLOBAL DEFAULT 8 __kernel_gettimeofday 50: 0000000000000614 172 NOTYPE GLOBAL DEFAULT 8 __kernel_sync_dicache 51: 00000000000006f0 84 NOTYPE GLOBAL DEFAULT 8 __kernel_getrandom 52: 0000000000000454 12 NOTYPE GLOBAL DEFAULT 8 __kernel_sigtram[...] 53: 0000000000000578 68 NOTYPE GLOBAL DEFAULT 8 __kernel_time 54: 00000000000004d0 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_g[...] 55: 00000000000005bc 52 NOTYPE GLOBAL DEFAULT 8 __kernel_get_sys[...] Fixes: 98eedc3a9dbf ("Document the vDSO and add a reference parser") Signed-off-by: Christophe Leroy Acked-by: Shuah Khan Signed-off-by: Jason A. Donenfeld Signed-off-by: Sasha Levin

selftests/vDSO: fix clang build errors and warnings

2024-07-27T08:40:21+00:00

[ Upstream commit 73810cd45b99c6c418e1c6a487b52c1e74edb20d ] When building with clang, via: make LLVM=1 -C tools/testing/selftests ...there are several warnings, and an error. This fixes all of those and allows these tests to run and pass. 1. Fix linker error (undefined reference to memcpy) by providing a local version of memcpy. 2. clang complains about using this form: if (g = h & 0xf0000000) ...so factor out the assignment into a separate step. 3. The code is passing a signed const char* to elf_hash(), which expects a const unsigned char *. There are several callers, so fix this at the source by allowing the function to accept a signed argument, and then converting to unsigned operations, once inside the function. 4. clang doesn't have __attribute__((externally_visible)) and generates a warning to that effect. Fortunately, gcc 12 and gcc 13 do not seem to require that attribute in order to build, run and pass tests here, so remove it. Reviewed-by: Carlos Llamas Reviewed-by: Edward Liaw Reviewed-by: Muhammad Usama Anjum Tested-by: Muhammad Usama Anjum Signed-off-by: John Hubbard Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests: vdso: Add a selftest for vDSO getcpu()

2020-05-22T17:05:07+00:00

Provide a very basic selftest for getcpu() which similarly to our existing test for gettimeofday() looks up the function in the vDSO and prints the results it gets if the function exists and succeeds. Signed-off-by: Mark Brown Signed-off-by: Shuah Khan

selftests: vdso: Use a header file to prototype parse_vdso API

2020-05-22T17:04:10+00:00

Both vdso_test_gettimeofday and vdso_standalone_test_x86 use the library in parse_vdso.c but each separately declares the API it offers which is not ideal. Create a header file with prototypes of the functions and use it in both the library and the tests to ensure that the same prototypes are used throughout. Signed-off-by: Mark Brown Signed-off-by: Shuah Khan

selftests: vdso: Rename vdso_test to vdso_test_gettimeofday

2020-05-22T15:49:49+00:00

Currently the vDSO kselftests have a test called vdso_test which tests the vDSO implementation of gettimeofday(). In preparation for adding tests for other vDSO functionality rename this test to reflect what's going on. Signed-off-by: Mark Brown Signed-off-by: Shuah Khan

.gitignore: add SPDX License Identifier

2020-03-25T10:50:48+00:00

Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada Signed-off-by: Greg Kroah-Hartman

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 180

2019-05-30T18:29:20+00:00

Based on 1 normalized pattern(s): subject to the gnu general public license version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Steve Winslow Reviewed-by: Richard Fontana Reviewed-by: Armijn Hemel Reviewed-by: Allison Randal Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528170026.343113277@linutronix.de Signed-off-by: Greg Kroah-Hartman

selftests: vDSO - fix to return KSFT_SKIP when test couldn't be run

2018-07-11T16:14:26+00:00

Fix to return KSFT_SKIP when test couldn't be run because AT_SYSINFO_EHDR isn't found and gettimeofday isn't defined. Signed-off-by: Shuah Khan (Samsung OSG)

selftests: vDSO - fix to exclude x86 test on non-x86 platforms

2018-07-11T16:14:14+00:00

Fix to exclude vdso_standalone_test_x86 test from building on non-x86 platforms. In addition, fix it to use TEST_GEN_PROGS which is the right variable to use for generated programs. TEST_PROGS is for shell scripts. Signed-off-by: Shuah Khan (Samsung OSG)