On Tue, 2007-03-06 at 14:20 +0100, Ingo Molnar wrote: > * Rusty Russell <[EMAIL PROTECTED]> wrote: > > > +/* The boot Global Descriptor Table: after boot we allocate a per-cpu copy > > */ > > .align L1_CACHE_BYTES > > ENTRY(boot_gdt_table) > > - .fill GDT_ENTRY_BOOT_CS,8,0 > > - .quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */ > > - .quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */ > > - > > -/* > > - * The Global Descriptor Table contains 28 quadwords, per-CPU. > > - */ > > - .align L1_CACHE_BYTES > > -ENTRY(cpu_gdt_table) > > .quad 0x0000000000000000 /* NULL descriptor */ > > .quad 0x0000000000000000 /* 0x0b reserved */ > > - .quad 0x0000000000000000 /* 0x13 reserved */ > > - .quad 0x0000000000000000 /* 0x1b reserved */ > > + .quad 0x00cf9a000000ffff /* boot: 4GB code at 0x00000000 */ > > + .quad 0x00cf92000000ffff /* boot: 4GB data at 0x00000000 */ > > .quad 0x0000000000000000 /* 0x20 unused */ > > .quad 0x0000000000000000 /* 0x28 unused */ > > .quad 0x0000000000000000 /* 0x33 TLS entry 1 */ > > actually, the reason for the small boot GDT was that some systems > wouldnt even boot with a larger GDT. (there was some BIOS interaction, > forgot what it was - iirc it was mach-visws and also some other older > box)
Thanks for the explanation: I did wonder! I left the descriptor truncated to just the first few entries, so I'm *pretty sure* it won't matter: the layout is identical. I'd really like to try it and see, though; Andre? Rusty. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
