diff --git a/tests/hd-geo-test.c b/tests/hd-geo-test.c
new file mode 100644
index 0000000..cc447a2
--- /dev/null
+++ b/tests/hd-geo-test.c
@@ -0,0 +1,403 @@
+/*
+ * Hard disk geometry test cases.
+ *
+ * Copyright (c) 2012 Red Hat Inc.
+ *
+ * Authors:
+ *  Markus Armbruster <armbru@redhat.com>,
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+/*
+ * Covers only IDE and tests only CMOS contents.  Better than nothing.
+ * Improvements welcome.
+ */
+
+#include <glib.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "qemu-common.h"
+#include "libqtest.h"
+
+static const char test_image[] = "/tmp/qtest.XXXXXX";
+
+static char *create_test_img(int secs)
+{
+    char *template = strdup("/tmp/qtest.XXXXXX");
+    int fd, ret;
+
+    fd = mkstemp(template);
+    g_assert(fd >= 0);
+    ret = ftruncate(fd, (off_t)secs * 512);
+    g_assert(ret == 0);
+    close(fd);
+    return template;
+}
+
+typedef struct {
+    int cyls, heads, secs, trans;
+} CHST;
+
+typedef enum {
+    mbr_blank, mbr_lba, mbr_chs,
+    mbr_last
+} MBRcontents;
+
+typedef enum {
+    /* order is relevant */
+    backend_small, backend_large, backend_empty,
+    backend_last
+} Backend;
+
+static const int img_secs[backend_last] = {
+    [backend_small] = 61440,
+    [backend_large] = 8388608,
+    [backend_empty] = -1,
+};
+
+static const CHST hd_chst[backend_last][mbr_last] = {
+    [backend_small] = {
+        [mbr_blank] = { 60, 16, 63, 0 },
+        [mbr_lba]   = { 60, 16, 63, 2 },
+        [mbr_chs]   = { 60, 16, 63, 0 }
+    },
+    [backend_large] = {
+        [mbr_blank] = { 8322, 16, 63, 1 },
+        [mbr_lba]   = { 8322, 16, 63, 1 },
+        [mbr_chs]   = { 8322, 16, 63, 0 }
+    },
+};
+
+static const char *img_file_name[backend_last];
+
+static const CHST *cur_ide[4];
+
+static bool is_hd(const CHST *expected_chst)
+{
+    return expected_chst && expected_chst->cyls;
+}
+
+static void test_cmos_byte(int reg, int expected)
+{
+    enum { cmos_base = 0x70 };
+    int actual;
+
+    outb(cmos_base + 0, reg);
+    actual = inb(cmos_base + 1);
+    g_assert(actual == expected);
+}
+
+static void test_cmos_bytes(int reg0, int n, uint8_t expected[])
+{
+    int i;
+
+    for (i = 0; i < 9; i++) {
+        test_cmos_byte(reg0 + i, expected[i]);
+    }
+}
+
+static void test_cmos_disk_data(void)
+{
+    test_cmos_byte(0x12,
+                   (is_hd(cur_ide[0]) ? 0xf0 : 0) |
+                   (is_hd(cur_ide[1]) ? 0x0f : 0));
+}
+
+static void test_cmos_drive_cyl(int reg0, const CHST *expected_chst)
+{
+    if (is_hd(expected_chst)) {
+        int c = expected_chst->cyls;
+        int h = expected_chst->heads;
+        int s = expected_chst->secs;
+        uint8_t expected_bytes[9] = {
+            c & 0xff, c >> 8, h, 0xff, 0xff, 0xc0 | ((h > 8) << 3),
+            c & 0xff, c >> 8, s
+        };
+        test_cmos_bytes(reg0, 9, expected_bytes);
+    } else {
+        int i;
+
+        for (i = 0; i < 9; i++) {
+            test_cmos_byte(reg0 + i, 0);
+        }
+    }
+}
+
+static void test_cmos_drive1(void)
+{
+    test_cmos_byte(0x19, is_hd(cur_ide[0]) ? 47 : 0);
+    test_cmos_drive_cyl(0x1b, cur_ide[0]);
+}
+
+static void test_cmos_drive2(void)
+{
+    test_cmos_byte(0x1a, is_hd(cur_ide[1]) ? 47 : 0);
+    test_cmos_drive_cyl(0x24, cur_ide[1]);
+}
+
+static void test_cmos_disktransflag(void)
+{
+    int val, i;
+
+    val = 0;
+    for (i = 0; i < ARRAY_SIZE(cur_ide); i++) {
+        if (is_hd(cur_ide[i])) {
+            val |= cur_ide[i]->trans << (2 * i);
+        }
+    }
+    test_cmos_byte(0x39, val);
+}
+
+static void test_cmos(void)
+{
+    test_cmos_disk_data();
+    test_cmos_drive1();
+    test_cmos_drive2();
+    test_cmos_disktransflag();
+}
+
+static int append_arg(int argc, char *argv[], int argv_sz, char *arg)
+{
+    g_assert(argc + 1 < argv_sz);
+    argv[argc++] = arg;
+    argv[argc] = NULL;
+    return argc;
+}
+
+static int setup_common(char *argv[], int argv_sz)
+{
+    memset(cur_ide, 0, sizeof(cur_ide));
+    return append_arg(0, argv, argv_sz,
+                      g_strdup("-nodefaults -display none"));
+}
+
+static void setup_mbr(int img_idx, MBRcontents mbr)
+{
+    static const uint8_t part_lba[16] = {
+        /* chs 0,1,1 (lba 63) to chs 0,127,63 (8001 sectors) */
+        0x80, 1, 1, 0, 6, 127, 63, 0, 63, 0, 0, 0, 0x41, 0x1F, 0, 0,
+    };
+    static const uint8_t part_chs[16] = {
+        /* chs 0,1,1 (lba 63) to chs 7,15,63 (8001 sectors) */
+        0x80, 1, 1, 0, 6,  15, 63, 7, 63, 0, 0, 0, 0x41, 0x1F, 0, 0,
+    };
+    uint8_t buf[512];
+    int fd, ret;
+
+    memset(buf, 0, sizeof(buf));
+
+    if (mbr != mbr_blank) {
+        buf[0x1fe] = 0x55;
+        buf[0x1ff] = 0xAA;
+        memcpy(buf + 0x1BE, mbr == mbr_lba ? part_lba : part_chs, 16);
+    }
+
+    fd = open(img_file_name[img_idx], O_WRONLY);
+    g_assert(fd >= 0);
+    ret = write(fd, buf, sizeof(buf));
+    g_assert(ret == sizeof(buf));
+    close(fd);
+}
+
+static int setup_ide(int argc, char *argv[], int argv_sz,
+                     int ide_idx, const char *dev, int img_idx,
+                     MBRcontents mbr, const char *opts)
+{
+    char *s1, *s2, *s3;
+
+    s1 = g_strdup_printf("-drive id=drive%d,if=%s",
+                         ide_idx, dev ? "none" : "ide");
+    s2 = dev ? g_strdup("") : g_strdup_printf(",index=%d", ide_idx);
+
+    if (img_secs[img_idx] >= 0) {
+        setup_mbr(img_idx, mbr);
+        s3 = g_strdup_printf(",file=%s", img_file_name[img_idx]);
+    } else {
+        s3 = g_strdup(",media=cdrom");
+    }
+    argc = append_arg(argc, argv, argv_sz,
+                      g_strdup_printf("%s%s%s%s", s1, s2, s3, opts));
+    g_free(s1);
+    g_free(s2);
+    g_free(s3);
+
+    if (dev) {
+        argc = append_arg(argc, argv, argv_sz,
+                          g_strdup_printf("-device %s,drive=drive%d,"
+                                          "bus=ide.%d,unit=%d",
+                                          dev, ide_idx,
+                                          ide_idx / 2, ide_idx % 2));
+    }
+    return argc;
+}
+
+/*
+ * Test case: no IDE devices
+ */
+static void test_ide_none(void)
+{
+    char *argv[256];
+
+    setup_common(argv, ARRAY_SIZE(argv));
+    qtest_start(g_strjoinv(" ", argv));
+    test_cmos();
+    qtest_quit(global_qtest);
+}
+
+static void test_ide_mbr(bool use_device, MBRcontents mbr)
+{
+    char *argv[256];
+    int argc;
+    Backend i;
+    const char *dev;
+
+    argc = setup_common(argv, ARRAY_SIZE(argv));
+    for (i = 0; i < backend_last; i++) {
+        cur_ide[i] = &hd_chst[i][mbr];
+        dev = use_device ? (is_hd(cur_ide[i]) ? "ide-hd" : "ide-cd") : NULL;
+        argc = setup_ide(argc, argv, ARRAY_SIZE(argv), i, dev, i, mbr, "");
+    }
+    qtest_start(g_strjoinv(" ", argv));
+    test_cmos();
+    qtest_quit(global_qtest);
+}
+
+/*
+ * Test case: IDE devices (if=ide) with blank MBRs
+ */
+static void test_ide_drive_mbr_blank(void)
+{
+    test_ide_mbr(false, mbr_blank);
+}
+
+/*
+ * Test case: IDE devices (if=ide) with MBRs indicating LBA is in use
+ */
+static void test_ide_drive_mbr_lba(void)
+{
+    test_ide_mbr(false, mbr_lba);
+}
+
+/*
+ * Test case: IDE devices (if=ide) with MBRs indicating CHS is in use
+ */
+static void test_ide_drive_mbr_chs(void)
+{
+    test_ide_mbr(false, mbr_chs);
+}
+
+/*
+ * Test case: IDE devices (if=none) with blank MBRs
+ */
+static void test_ide_device_mbr_blank(void)
+{
+    test_ide_mbr(true, mbr_blank);
+}
+
+/*
+ * Test case: IDE devices (if=none) with MBRs indicating LBA is in use
+ */
+static void test_ide_device_mbr_lba(void)
+{
+    test_ide_mbr(true, mbr_lba);
+}
+
+/*
+ * Test case: IDE devices (if=none) with MBRs indicating CHS is in use
+ */
+static void test_ide_device_mbr_chs(void)
+{
+    test_ide_mbr(true, mbr_chs);
+}
+
+static void test_ide_drive_user(const char *dev, bool trans)
+{
+    char *argv[256], *opts;
+    int argc;
+    int secs = img_secs[backend_small];
+    const CHST expected_chst = { secs / (4 * 32) , 4, 32, trans };
+
+    argc = setup_common(argv, ARRAY_SIZE(argv));
+    opts = g_strdup_printf(",cyls=%d,heads=%d,secs=%d%s",
+                           expected_chst.cyls, expected_chst.heads,
+                           expected_chst.secs,
+                           trans ? ",trans=lba" : "");
+    cur_ide[0] = &expected_chst;
+    argc = setup_ide(argc, argv, ARRAY_SIZE(argv),
+                     0, dev, backend_small, mbr_chs, opts);
+    g_free(opts);
+    qtest_start(g_strjoinv(" ", argv));
+    test_cmos();
+    qtest_quit(global_qtest);
+}
+
+/*
+ * Test case: IDE device (if=ide) with explicit CHS
+ */
+static void test_ide_drive_user_chs(void)
+{
+    test_ide_drive_user(NULL, false);
+}
+
+/*
+ * Test case: IDE device (if=ide) with explicit CHS and translation
+ */
+static void test_ide_drive_user_chst(void)
+{
+    test_ide_drive_user(NULL, true);
+}
+
+/*
+ * Test case: IDE device (if=none) with explicit CHS
+ */
+static void test_ide_device_user_chs(void)
+{
+    test_ide_drive_user("ide-hd", false);
+}
+
+/*
+ * Test case: IDE device (if=none) with explicit CHS and translation
+ */
+static void test_ide_device_user_chst(void)
+{
+    test_ide_drive_user("ide-hd", true);
+}
+
+int main(int argc, char **argv)
+{
+    Backend i;
+    int ret;
+
+    g_test_init(&argc, &argv, NULL);
+
+    for (i = 0; i < backend_last; i++) {
+        if (img_secs[i] >= 0) {
+            img_file_name[i] = create_test_img(img_secs[i]);
+        } else {
+            img_file_name[i] = NULL;
+        }
+    }
+
+    qtest_add_func("hd-geo/ide/none", test_ide_none);
+    qtest_add_func("hd-geo/ide/drive/mbr/blank", test_ide_drive_mbr_blank);
+    qtest_add_func("hd-geo/ide/drive/mbr/lba", test_ide_drive_mbr_lba);
+    qtest_add_func("hd-geo/ide/drive/mbr/chs", test_ide_drive_mbr_chs);
+    qtest_add_func("hd-geo/ide/drive/user/chs", test_ide_drive_user_chs);
+    qtest_add_func("hd-geo/ide/drive/user/chst", test_ide_drive_user_chst);
+    qtest_add_func("hd-geo/ide/device/mbr/blank", test_ide_device_mbr_blank);
+    qtest_add_func("hd-geo/ide/device/mbr/lba", test_ide_device_mbr_lba);
+    qtest_add_func("hd-geo/ide/device/mbr/chs", test_ide_device_mbr_chs);
+    qtest_add_func("hd-geo/ide/device/user/chs", test_ide_device_user_chs);
+    qtest_add_func("hd-geo/ide/device/user/chst", test_ide_device_user_chst);
+
+    ret = g_test_run();
+
+    for (i = 0; i < backend_last; i++) {
+        unlink(img_file_name[i]);
+    }
+
+    return ret;
+}