Re: Linux 2.6.27-rc5: System boot regression caused by commit a2bd7274b47124d2fc4dfdb8c0591f545ba749dd

Linus Torvalds
2008-08-31T17:44:15Z

On Sun, 31 Aug 2008, Rafael J. Wysocki wrote:
>
> Works, dmesg is at:
> http://www.sisk.pl/kernel/debug/mainline/2.6.27-rc5/2.6.27-rc5-test.log

That BAR is indeed "locked". Now that we try to reallocate it, you get
this in the log:

pci 0000:00:00.0: BAR 3: error updating (0x40000004 != 0xe0000004)
pci 0000:00:00.0: BAR 3: error updating (high 0x000001 != 0x000000)

ie now the code _tried_ to update the BAR to point to 0x1_4000_0000
instead, but the hardware refused, and it is still at 0x0_e000_0000.

So Yinghai's patch "worked", but it worked by doing nothing.

See my earlier guess about locked read-only resources a few emails back.
IOW, I'm not at all surprised. I really do suspect that that BAR is some
very special "this is the HT->PCIE region" BAR.

Linus