Re: [PATCH 4/5] selftests/liveupdate: Add stress-sessions kexec test

[Pratyush Yadav <pratyush@kernel.org>]

On Tue, Apr 14 2026, Pasha Tatashin wrote:

> Add a new test that creates 2000 LUO sessions before a kexec
> reboot and verifies their presence after the reboot. This ensures
> that the linked-block serialization mechanism works correctly for
> a large number of sessions.
>
> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> ---
> diff --git a/tools/testing/selftests/liveupdate/luo_test_utils.c b/tools/testing/selftests/liveupdate/luo_test_utils.c
> index 3c8721c505df..37c330b9bb36 100644
> --- a/tools/testing/selftests/liveupdate/luo_test_utils.c
> +++ b/tools/testing/selftests/liveupdate/luo_test_utils.c
> @@ -20,6 +20,7 @@
>  #include <sys/stat.h>
>  #include <errno.h>
>  #include <stdarg.h>
> +#include <sys/resource.h>
>  
>  #include "luo_test_utils.h"
>  
> @@ -28,6 +29,30 @@ int luo_open_device(void)
>  	return open(LUO_DEVICE, O_RDWR);
>  }
>  
> +void luo_ensure_nofile_limit(long min_limit)

Since you are adding this to luo_test_utils anyway, I think you should
do it in patch 3 and use it there too.

LGTM otherwise.

> +{
> +	struct rlimit hl;
> +
> +	if (getrlimit(RLIMIT_NOFILE, &hl) < 0)
> +		ksft_exit_fail_msg("getrlimit failed: %s\n", strerror(errno));
> +
> +	if (hl.rlim_cur >= min_limit)
> +		return;
> +
> +	hl.rlim_cur = min_limit;
> +	if (hl.rlim_cur > hl.rlim_max)
> +		hl.rlim_max = hl.rlim_cur;
> +
> +	if (setrlimit(RLIMIT_NOFILE, &hl) < 0) {
> +		if (errno == EPERM) {
> +			ksft_exit_skip("Insufficient privileges to set RLIMIT_NOFILE to %ld\n",
> +				       hl.rlim_cur);
> +		}
> +		ksft_exit_fail_msg("setrlimit to %ld failed: %s\n",
> +				   hl.rlim_cur, strerror(errno));
> +	}
> +}
> +
>  int luo_create_session(int luo_fd, const char *name)
>  {
>  	struct liveupdate_ioctl_create_session arg = { .size = sizeof(arg) };

-- 
Regards,
Pratyush Yadav