Author: cem Date: Fri Oct 30 19:02:59 2020 New Revision: 367182 URL: https://svnweb.freebsd.org/changeset/base/367182
Log: linux(4): Quiesce warning about madvise(..., -1) This API misuse is intended to produce an error value to detect certain bogus stub implementations of MADV_WIPEONFORK. We don't need to log a warning about it. Example: https://boringssl.googlesource.com/boringssl/+/ad5582985cc6b89d0e7caf0d9cc7e301de61cf66%5E%21/ Reviewed by: emaste, trasz Differential Revision: https://reviews.freebsd.org/D27017 Modified: head/sys/compat/linux/linux_mmap.c Modified: head/sys/compat/linux/linux_mmap.c ============================================================================== --- head/sys/compat/linux/linux_mmap.c Fri Oct 30 19:00:42 2020 (r367181) +++ head/sys/compat/linux/linux_mmap.c Fri Oct 30 19:02:59 2020 (r367182) @@ -394,6 +394,16 @@ linux_madvise_common(struct thread *td, uintptr_t addr case LINUX_MADV_SOFT_OFFLINE: linux_msg(curthread, "unsupported madvise MADV_SOFT_OFFLINE"); return (EINVAL); + case -1: + /* + * -1 is sometimes used as a dummy value to detect simplistic + * madvise(2) stub implementations. This safeguard is used by + * BoringSSL, for example, before assuming MADV_WIPEONFORK is + * safe to use. Don't produce an "unsupported" error message + * for this special dummy value, which is unlikely to be used + * by any new advisory behavior feature. + */ + return (EINVAL); default: linux_msg(curthread, "unsupported madvise behav %d", behav); return (EINVAL); _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
