Commit 3b3df3e5 authored by Laszlo Ersek's avatar Laszlo Ersek Committed by Michael S. Tsirkin
Browse files

fw_cfg: fix the life cycle and the name of "qemu_extra_params_fw" 



Commit 19bcc4bc ("fw_cfg: Make qemu_extra_params_fw locally",
2019-01-04) changed the storage duration of the "qemu_extra_params_fw"
array from static to automatic. This broke the interface contract on the
fw_cfg_add_file() function, which is documented as follows, in
"include/hw/nvram/fw_cfg.h":

> [...] The data referenced by the starting pointer is only linked, NOT
> copied, into the data structure of the fw_cfg device. [...]

As a result, when guest firmware fetches the "etc/boot-menu-wait" fw_cfg
file, it now sees garbage. Fix the regression by changing the storage
duration to allocated. (The call is reached at most once, on the realize
path of the board-specific fw_cfg sysbus device.)

While at it, clean up the name and the assignment of the object as well.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Fixes: 19bcc4bc
Signed-off-by: default avatarLaszlo Ersek <lersek@redhat.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: default avatarLi Qiang <liq3ea@gmail.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Reviewed-by: default avatarPhilippe Mathieu-Daudé <philmd@redhat.com>
parent 24cf5413

hw/nvram/fw_cfg.c

+5 −4
Original line number Diff line number Diff line
@@ -118,7 +118,6 @@ static void fw_cfg_bootsplash(FWCfgState *s) 
{

    const char *boot_splash_filename = NULL;

    const char *boot_splash_time = NULL;

    uint8_t qemu_extra_params_fw[2];

    char *filename, *file_data;

    gsize file_size;

    int file_type;
@@ -132,6 +131,8 @@ static void fw_cfg_bootsplash(FWCfgState *s) 
    /* insert splash time if user configurated */

    if (boot_splash_time) {

        int64_t bst_val = qemu_opt_get_number(opts, "splash-time", -1);

        uint16_t bst_le16;



        /* validate the input */

        if (bst_val < 0 || bst_val > 0xffff) {

            error_report("splash-time is invalid,"
@@ -139,9 +140,9 @@ static void fw_cfg_bootsplash(FWCfgState *s) 
            exit(1);

        }

        /* use little endian format */

        qemu_extra_params_fw[0] = (uint8_t)(bst_val & 0xff);

        qemu_extra_params_fw[1] = (uint8_t)((bst_val >> 8) & 0xff);

        fw_cfg_add_file(s, "etc/boot-menu-wait", qemu_extra_params_fw, 2);

        bst_le16 = cpu_to_le16(bst_val);

        fw_cfg_add_file(s, "etc/boot-menu-wait",

                        g_memdup(&bst_le16, sizeof bst_le16), sizeof bst_le16);

    }



    /* insert splash file if user configurated */