From: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Subject: userfaultfd: report actual registered features in fdinfo fdinfo for userfault file descriptor reports UFFD_API_FEATURES. Up until recently, the UFFD_API_FEATURES was defined as 0, therefore corresponding field in fdinfo always contained zero. Now, with introduction of several additional features, UFFD_API_FEATURES is not longer 0 and it seems better to report actual features requested for the userfaultfd object described by the fdinfo. First, the applications that were using userfault will still see zero at the features field in fdinfo. Next, reporting actual features rather than available features, gives clear indication of what userfault features are used by an application. Link: http://lkml.kernel.org/r/1491140181-22121-1-git-send-email-rppt@xxxxxxxxxxxxxxxxxx Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Reviewed-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/userfaultfd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN fs/userfaultfd.c~userfaultfd-report-actual-registered-features-in-fdinfo fs/userfaultfd.c --- a/fs/userfaultfd.c~userfaultfd-report-actual-registered-features-in-fdinfo +++ a/fs/userfaultfd.c @@ -1756,7 +1756,7 @@ static void userfaultfd_show_fdinfo(stru * protocols: aa:... bb:... */ seq_printf(m, "pending:\t%lu\ntotal:\t%lu\nAPI:\t%Lx:%x:%Lx\n", - pending, total, UFFD_API, UFFD_API_FEATURES, + pending, total, UFFD_API, ctx->features, UFFD_API_IOCTLS|UFFD_API_RANGE_IOCTLS); } #endif _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
