* Gavin Shan:
> diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
> index a54d4d05a058..acb1bf1f06b3 100644
> --- a/tools/testing/selftests/kvm/rseq_test.c
> +++ b/tools/testing/selftests/kvm/rseq_test.c
> @@ -9,6 +9,7 @@
> #include <string.h>
> #include <signal.h>
> #include <syscall.h>
> +#include <dlfcn.h>
> #include <sys/ioctl.h>
> #include <sys/sysinfo.h>
> #include <asm/barrier.h>
I'm surprised that there isn't a Makefile update to link with -ldl
(still required for glibc 2.33 and earlier).
> @@ -36,6 +37,8 @@ static __thread volatile struct rseq __rseq = {
> */
> #define NR_TASK_MIGRATIONS 100000
>
> +static bool __rseq_ownership;
> +static volatile struct rseq *__rseq_info;
> static pthread_t migration_thread;
> static cpu_set_t possible_mask;
> static int min_cpu, max_cpu;
> @@ -49,11 +52,33 @@ static void guest_code(void)
> GUEST_SYNC(0);
> }
>
> +static void sys_rseq_ownership(void)
> +{
> + long *offset;
> + unsigned int *size, *flags;
> +
> + offset = dlsym(RTLD_NEXT, "__rseq_offset");
> + size = dlsym(RTLD_NEXT, "__rseq_size");
> + flags = dlsym(RTLD_NEXT, "__rseq_flags");
> +
> + if (offset && size && *size && flags) {
> + __rseq_ownership = false;
> + __rseq_info = (struct rseq *)((uintptr_t)__builtin_thread_pointer() +
> + *offset);
__builtin_thread_pointer doesn't work on all architectures/GCC versions.
Is this a problem for selftests?
Thanks,
Florian
