From d1e6994abcd12c7f54aa73ff848fb6215c783898 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Wed, 13 Sep 2017 16:20:35 +0200 Subject: [PATCH] dump: do not dump non-existent guest memory It does not really make sense to dump memory that is not there. Moreover, that fixes a segmentation fault when calling dump-guest-memory with no filter for a machine with no memory defined. New behaviour is: (qemu) dump-guest-memory /dev/null dump: no guest memory to dump (qemu) dump-guest-memory /dev/null 0 4096 dump: no guest memory to dump Signed-off-by: Cornelia Huck Tested-by: Laurent Vivier Reviewed-by: Laurent Vivier Reviewed-by: Greg Kurz Reviewed-by: Peter Xu Message-Id: <20170913142036.2469-4-lvivier@redhat.com> Signed-off-by: Laurent Vivier Signed-off-by: Dr. David Alan Gilbert --- dump.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/dump.c b/dump.c index a79773d0f7..d2093e141b 100644 --- a/dump.c +++ b/dump.c @@ -1536,6 +1536,12 @@ static void dump_init(DumpState *s, int fd, bool has_format, fprintf(stderr, "DUMP: total memory to dump: %lu\n", s->total_size); #endif + /* it does not make sense to dump non-existent memory */ + if (!s->total_size) { + error_setg(errp, "dump: no guest memory to dump"); + goto cleanup; + } + s->start = get_start_block(s); if (s->start == -1) { error_setg(errp, QERR_INVALID_PARAMETER, "begin");