Re: Bisected regression (Was Re: current -git fails to boot on nehalem-ex)

[Jens Axboe <jens.axboe@oracle.com>]

On Thu, Dec 10 2009, Yinghai Lu wrote:
> Jens Axboe wrote:
> > On Thu, Dec 10 2009, Jens Axboe wrote:
> >>>>> [    0.000000] Kernel panic - not syncing: Overlapping early reservations 12-f011 MP-table mpc to 0-fff BIOS data page
> >>>> mptable mpc is [12 - f011]
> >>>>
> >>>> what a BIOS !
> >>>>
> >>>> can you check if it works with 2.6.32 + "acpi=off"?
> >> I'll try that.
> > 
> > Yes, 2.6.32 boots fine with acpi=off passed.
> > 
> >>> please check if this one could workaround it.
> >>>
> >>> diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
> >>> index d17d482..f60acec 100644
> >>> --- a/arch/x86/kernel/e820.c
> >>> +++ b/arch/x86/kernel/e820.c
> >>> @@ -732,7 +732,7 @@ struct early_res {
> >>>  	char overlap_ok;
> >>>  };
> >>>  static struct early_res early_res[MAX_EARLY_RES] __initdata = {
> >>> -	{ 0, PAGE_SIZE, "BIOS data page" },	/* BIOS data page */
> >>> +	{ 0, PAGE_SIZE, "BIOS data page", 1 },	/* BIOS data page */
> >>>  	{}
> >>>  };
> >> And then this. Results in 10-15min.
> > 
> > Doesn't work, it just complains about a different overlap:
> > 
> > [    0.000000] Kernel panic - not syncing: Overlapping early
> > reservations 12-f011 MP-table mpc to 6000-7fff TRAMPOLINE
> > [    0.000000] 
> > [    0.000000] Pid: 0, comm: swapper Not tainted 2.6.32 #51
> > [    0.000000] Call Trace:
> > [    0.000000]  [<ffffffff813c709b>] panic+0xa0/0x16a
> > [    0.000000]  [<ffffffff8167d280>] ?
> > reserve_early_overlap_ok+0x2e/0x39
> > [    0.000000]  [<ffffffff8167d24a>] ?
> > drop_overlaps_that_are_ok+0x117/0x11f
> > [    0.000000]  [<ffffffff8167d133>] drop_overlaps_that_are_ok+0x0/0x11f
> > [    0.000000]  [<ffffffff8167d2c6>] reserve_early+0x3b/0x3d
> > [    0.000000]  [<ffffffff81683248>] smp_scan_config+0xe7/0x10e
> > [    0.000000]  [<ffffffff816832a9>] default_find_smp_config+0x3a/0x60
> > [    0.000000]  [<ffffffff8167b0be>] setup_arch+0x6ae/0xa88
> > [    0.000000]  [<ffffffff816789ff>] start_kernel+0x82/0x412
> > [    0.000000]  [<ffffffff81678289>] x86_64_start_reservations+0x99/0xb9
> > [    0.000000]  [<ffffffff81678389>] x86_64_start_kernel+0xe0/0xf2
> > 
> > 
> 
> that is funny. we may need to use find early for our TRAMPOLINE...?
> 
> otherwise your mptable is corrupted....

Roland, are you filing a report for this?

I can test other patches if you have good ideas, otherwise I suggest we
revert the commit.

-- 
Jens Axboe