Podés especificarle cuántas palabras de qué tamaño te despliega. Como no lo estás especificando te está desplegando una palabra de tamaño "word" (4 bytes)-
Fijate en la ayuda del comando x (escribí "help x" y apretá enter en la consola de gdb).
Saludos,
julio
(qemu-gdb)help x
Examine memory: x/FMT ADDRESS.
ADDRESS is an expression for the memory address to examine.
FMT is a repeat count followed by a format letter and a size letter.
Format letters are o(octal), x(hex), d(decimal), u(unsigned decimal),
t(binary), f(float), a(address), i(instruction), c(char) and s(string).
Size letters are b(byte), h(halfword), w(word), g(giant, 8 bytes).
The specified number of objects of the specified size are printed
according to the format.
Defaults for format and size letters are those previously used.
Default count is 1. Default address is following last thing printed
with this command or "print".