lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 2 Apr 2015 18:05:10 -0700 (PDT) From: Hugh Dickins <hughd@...gle.com> To: David Rientjes <rientjes@...gle.com> cc: Andrew Morton <akpm@...ux-foundation.org>, Hugh Dickins <hughd@...gle.com>, Jonathan Corbet <corbet@....net>, Davide Libenzi <davidel@...ilserver.org>, Luiz Capitulino <lcapitulino@...hat.com>, Shuah Khan <shuahkh@....samsung.com>, Andrea Arcangeli <aarcange@...hat.com>, Joern Engel <joern@...fs.org>, Jianguo Wu <wujianguo@...wei.com>, Eric B Munson <emunson@...mai.com>, linux-mm@...ck.org, linux-kernel@...r.kernel.org, linux-api@...r.kernel.org, linux-doc@...r.kernel.org Subject: Re: [patch -mm] mm, doc: cleanup and clarify munmap behavior for hugetlb memory fix On Thu, 2 Apr 2015, David Rientjes wrote: > Don't only specify munmap(2) behavior with respect the hugetlb memory, all > other syscalls get naturally aligned to the native page size of the > processor. Rather, pick out munmap(2) as a specific example. > > Signed-off-by: David Rientjes <rientjes@...gle.com> Thanks, yes, good wording: it is best to be a bit vague here, since each msyscall takes the approach most convenient for it. Acked-by: Hugh Dickins <hughd@...gle.com> > --- > Documentation/vm/hugetlbpage.txt | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/vm/hugetlbpage.txt > index 1270fb1..030977f 100644 > --- a/Documentation/vm/hugetlbpage.txt > +++ b/Documentation/vm/hugetlbpage.txt > @@ -313,8 +313,11 @@ into /proc/sys/vm/hugetlb_shm_group. It is possible for same or different > applications to use any combination of mmaps and shm* calls, though the mount of > filesystem will be required for using mmap calls without MAP_HUGETLB. > > -When using munmap(2) to unmap hugetlb memory, the length specified must be > -hugepage aligned, otherwise it will fail with errno set to EINVAL. > +Syscalls that operate on memory backed by hugetlb pages only have their lengths > +aligned to the native page size of the processor; they will normally fail with > +errno set to EINVAL or exclude hugetlb pages that extend beyond the length if > +not hugepage aligned. For example, munmap(2) will fail if memory is backed by > +a hugetlb page and the length is smaller than the hugepage size. > > > Examples -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists