• Jason Baron's avatar
    coredump: add VM_NODUMP, MADV_NODUMP, MADV_CLEAR_NODUMP · accb61fe
    Jason Baron authored
    Since we no longer need the VM_ALWAYSDUMP flag, let's use the freed bit
    for 'VM_NODUMP' flag.  The idea is is to add a new madvise() flag:
    MADV_DONTDUMP, which can be set by applications to specifically request
    memory regions which should not dump core.
    
    The specific application I have in mind is qemu: we can add a flag there
    that wouldn't dump all of guest memory when qemu dumps core.  This flag
    might also be useful for security sensitive apps that want to absolutely
    make sure that parts of memory are not dumped.  To clear the flag use:
    MADV_DODUMP.
    
    [akpm@linux-foundation.org: s/MADV_NODUMP/MADV_DONTDUMP/, s/MADV_CLEAR_NODUMP/MADV_DODUMP/, per Roland]
    [akpm@linux-foundation.org: fix up the architectures which broke]
    Signed-off-by: default avatarJason Baron <jbaron@redhat.com>
    Acked-by: default avatarRoland McGrath <roland@hack.frob.com>
    Cc: Chris Metcalf <cmetcalf@tilera.com>
    Cc: Avi Kivity <avi@redhat.com>
    Cc: Ralf Baechle <ralf@linux-mips.org>
    Cc: Richard Henderson <rth@twiddle.net>
    Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
    Cc: Matt Turner <mattst88@gmail.com>
    Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
    Cc: Helge Deller <deller@gmx.de>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    accb61fe
madvise.c 11.7 KB