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[x86 setup] edd.c: make sure MBR signatures actually get reported

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When filling in the MBR signature array, the setup code failed to advance
boot_params.edd_mbr_sig_buf_entries, which resulted in the valid data
being ignored.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
H. Peter Anvin 2007-08-14 17:36:00 -07:00
parent c1a6e2b082
commit 9a5f35d4ed
1 changed files with 11 additions and 13 deletions
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24
arch/i386/boot/edd.c
View file

@ -37,11 +37,10 @@ static int read_mbr(u8 devno, void *buf)
return -(u8)ax; /* 0 or -1 */
}
static u32 read_mbr_sig(u8 devno, struct edd_info *ei)
static u32 read_mbr_sig(u8 devno, struct edd_info *ei, u32 *mbrsig)
{
int sector_size;
char *mbrbuf_ptr, *mbrbuf_end;
u32 mbrsig;
u32 buf_base, mbr_base;
extern char _end[];
@ -57,15 +56,15 @@ static u32 read_mbr_sig(u8 devno, struct edd_info *ei)
/* Make sure we actually have space on the heap... */
if (!(boot_params.hdr.loadflags & CAN_USE_HEAP))
return 0;
return -1;
if (mbrbuf_end > (char *)(size_t)boot_params.hdr.heap_end_ptr)
return 0;
return -1;
if (read_mbr(devno, mbrbuf_ptr))
return 0;
return -1;
mbrsig = *(u32 *)&mbrbuf_ptr[EDD_MBR_SIG_OFFSET];
return mbrsig;
*mbrsig = *(u32 *)&mbrbuf_ptr[EDD_MBR_SIG_OFFSET];
return 0;
}
static int get_edd_info(u8 devno, struct edd_info *ei)
@ -132,6 +131,7 @@ void query_edd(void)
int do_edd = 1;
int devno;
struct edd_info ei, *edp;
u32 *mbrptr;
if (cmdline_find_option("edd", eddarg, sizeof eddarg) > 0) {
if (!strcmp(eddarg, "skipmbr") || !strcmp(eddarg, "skip"))
@ -140,7 +140,8 @@ void query_edd(void)
do_edd = 0;
}
edp = (struct edd_info *)boot_params.eddbuf;
edp = boot_params.eddbuf;
mbrptr = boot_params.edd_mbr_sig_buffer;
if (!do_edd)
return;
@ -158,11 +159,8 @@ void query_edd(void)
boot_params.eddbuf_entries++;
}
if (do_mbr) {
u32 mbr_sig;
mbr_sig = read_mbr_sig(devno, &ei);
boot_params.edd_mbr_sig_buffer[devno-0x80] = mbr_sig;
}
if (do_mbr && !read_mbr_sig(devno, &ei, mbrptr++))
boot_params.edd_mbr_sig_buf_entries = devno-0x80+1;
}
}