Re: [PATCH v3 23/23] x86/vdso/selftest: Add a test for unmapping vDSO

[Shuah Khan]

On 6/11/21 12:02 PM, Dmitry Safonov wrote:
> Output for landing on x86:
> > [root@localhost ~]# ./test_munmap_vdso_64
> > 	AT_SYSINFO_EHDR is 0x7fffead9f000
> > [NOTE]	unmapping vDSO: [0x7fffead9f000, 0x7fffeada0000]
> > [NOTE]	vDSO partial move failed, will try with bigger size
> > [NOTE]	unmapping vDSO: [0x7fffead9f000, 0x7fffeada1000]
> > [OK]
> > [root@localhost ~]# ./test_munmap_vdso_32
> > 	AT_SYSINFO_EHDR is 0xf7eef000
> > [NOTE]	unmapping vDSO: [0xf7eef000, 0xf7ef0000]
> > [NOTE]	vDSO partial move failed, will try with bigger size
> > [NOTE]	unmapping vDSO: [0xf7eef000, 0xf7ef1000]
> > [OK]
>
> The test also can check force_sigsegv(SIGSEGV) in do_fast_syscall_32():
> > [root@localhost ~]# ./test_munmap_vdso_32 sysenter
> > [NOTE]	Using sysenter after munmap
> > 	AT_SYSINFO_EHDR is 0xf7efe000
> > [NOTE]	unmapping vDSO: [0xf7efe000, 0xf7eff000]
> > [NOTE]	vDSO partial move failed, will try with bigger size
> > [NOTE]	unmapping vDSO: [0xf7efe000, 0xf7f00000]
> > [OK]	32-bit process gets segfault on fast syscall with unmapped vDSO
>
> Cc: Shuah Khan <shuah@xxxxxxxxxx>
> Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
> ---
>   tools/testing/selftests/x86/.gitignore        |   1 +
>   tools/testing/selftests/x86/Makefile          |  11 +-
>   .../testing/selftests/x86/test_munmap_vdso.c  | 151 ++++++++++++++++++
>   3 files changed, 158 insertions(+), 5 deletions(-)
>   create mode 100644 tools/testing/selftests/x86/test_munmap_vdso.c

I can take this through kselftest tree for 5.14 - are there any
dependencies on x86 tree, I should be aware of?

thanks,
-- Shuah