Function displaying console buffer always assumes its content lenght equal to console buffer size. This is not true and sometimes it sends garbage to the screen. This patch fixes this issue. Additionally, remove references to unused conringc variable. Signed-off-by: Daniel Kiper <daniel.kiper(a)oracle.com&gt; diff -Npru crash-6.1.4.orig/xen_hyper_command.c crash-6.1.4/xen_hyper_command.c --- crash-6.1.4.orig/xen_hyper_command.c 2013-02-14 21:38:54.000000000 +0100 +++ crash-6.1.4/xen_hyper_command.c 2013-03-14 15:03:58.045075917 +0100 @@ -585,11 +585,10 @@ xen_hyper_cmd_log(void) void xen_hyper_dump_log(void) { - uint conringc, conringp; - uint warp, start, len, idx, i; + uint conringp, warp, len, idx, i; ulong conring; char *buf; - char last; + char last = 0; uint32_t conring_size; if (get_symbol_type("conring", NULL, NULL) == TYPE_CODE_ARRAY) @@ -597,7 +596,6 @@ xen_hyper_dump_log(void) else get_symbol_data("conring", sizeof(ulong), &conring); - get_symbol_data("conringc", sizeof(uint), &conringc); get_symbol_data("conringp", sizeof(uint), &conringp); if (symbol_exists("conring_size")) @@ -605,21 +603,19 @@ xen_hyper_dump_log(void) else conring_size = XEN_HYPER_CONRING_SIZE; - warp = FALSE; if (conringp >= conring_size) { - if ((start = conringp & (conring_size - 1))) { - warp = TRUE; - } + idx = conringp & (conring_size - 1); + len = conring_size; + warp = TRUE; } else { - start = 0; + idx = 0; + len = conringp; + warp = FALSE; } buf = GETBUF(conring_size); readmem(conring, KVADDR, buf, conring_size, "conring contents", FAULT_ON_ERROR); - idx = start; - len = conring_size; - last = 0; wrap_around: for (i = idx; i < len; i++) {