Eric W. Biederman schrieb:
> Well reading through the relevant code would probably help, it
> lists fairly clearly which subset of the kernel format I support.
> Basically It must be at least protocol version 2.0 and it must
> be a bzImage (not a zImage), and it must have all of the appropriate
> magic numbers. ISO linux and grub support older revisions of
> the linux boot protocol.
Hmm. Let's see.
$ od -t x1z -w8 -Ax hello.bin
000000 eb fe 00 00 00 00 00 00 >........<
000008 00 00 00 00 00 00 00 00 >........<
*
0001f0 00 01 00 00 00 00 00 00 >........<
0001f8 00 00 00 00 00 00 55 aa >......U.<
000200 eb 55 48 64 72 53 04 02 >.UHdrS..<
000208 00 00 00 00 00 10 30 00 >......0.<
000210 00 01 00 00 00 00 00 00 >........<
000218 00 00 00 00 00 00 00 00 >........<
*
000228 00 00 00 00 ff ff ff ff >........<
000230 48 65 6c 6c 6f 4b 65 72 >HelloKer<
000238 6e 65 6c 20 31 2e 30 00 >nel 1.0.<
000240 48 65 6c 6c 6f 2c 20 77 >Hello, w<
000248 6f 72 6c 64 2c 20 30 78 >orld, 0x<
000250 78 78 78 78 21 0d 0a 8c >xxxx!...<
000258 c8 8e d8 8e c0 b1 04 88 >........<
000260 e3 30 ff d3 e3 d2 eb 81 >.0......<
000268 c3 30 30 88 3e 50 00 88 >.00.>P..<
000270 1e 51 00 88 c3 30 ff d3 >.Q...0..<
000278 e3 d2 eb 81 c3 30 30 88 >.....00.<
000280 3e 52 00 88 1e 53 00 b4 >>R...S..<
000288 03 b7 00 cd 10 b8 01 13 >........<
000290 bb 17 00 b9 17 00 bd 40 >.......@<
000298 00 cd 10 fb eb fe 00 00 >........<
0002a0 00 00 00 00 00 00 00 00 >........<
*
000400
> int bzImage_probe(const char *buf, off_t len)
> {
> struct x86_linux_header header;
> if (len < sizeof(header)) {
> return -1;
> }
Length of my image is 1K, When looking over that struct, it looks like
that struct is 32K long. Hmm? Looks strange to me. Must bzImages be at
least 32K long?
> memcpy(&header, buf, sizeof(header));
> if (memcmp(header.header_magic, "HdrS", 4) != 0) {
> if (probe_debug) {
> fprintf(stderr, "Not a bzImage\n");
> }
> return -1;
> }
header_magic is offset 0x202 (if the comments in x86-linux.h are
correct), and there is a "HdrS". So okay.
> if (header.boot_sector_magic != 0xAA55) {
> if (probe_debug) {
> fprintf(stderr, "No x86 boot sector present\n");
> }
> /* No x86 boot sector present */
> return -1;
> }
boot_sector_magic is 0x1FE, which is okay as well (at least on little
endian machines).
> if (header.protocol_version < 0x0200) {
> if (probe_debug) {
> fprintf(stderr, "Must be at least protocol version
> 2.00\n");
> }
> /* Must be at least protocol version 2.00 */
> return -1;
> }
protocol_version is 0x0204. Ok as well.
> if ((header.loadflags & 1) == 0) {
> if (probe_debug) {
> fprintf(stderr, "zImage not a bzImage\n");
> }
> /* Not a bzImage */
> return -1;
> }
loadflags = 0x01, so (loadflags & 1) != 0. Okay as well..
> /* I've got a bzImage */
Hmm. The only thing that is not okay is that my kernel is too small. Is
that limitation of 32K documented somewhere...?
Okay, I'll try to blow up my kernel a bit (with zeroes) and check if it
helps.
Michael
_______________________________________________
fastboot mailing list
[email protected]
https://lists.osdl.org/mailman/listinfo/fastboot
