Messages in this thread | | | Date | Mon, 26 Apr 2004 15:08:07 +0200 | From | Pavel Machek <> | Subject | Re: Bug#234976: kernel-source-2.6.4: Software Suspend doesn't work |
| |
Hi! On Mon 26-04-04 19:48:34, Herbert Xu wrote: > > Yes, but as I wrote, only on one of the machines in question. > > OK, I've finally found out why agpgart locks up the machine upon > resuming from swsusp/pmdisk. > > The reason is that the gatt table is remapped with ioremap_nocache, > which on i386 machines capable of PSE will result in 4M pages being > split. > > When swsusp/pmdisk copies the pages back, the top page table is > written before the entries that it points to are filled in. > Depending on whether the second-level table lies before or after > the 4M-page in question, this will result in a page fault. > > A simple solution is to copy the pages in reverse. This way the > top page table is filled in last which should resolve this particular > issue. The following patch does exactly that and fixes the problem > for me.
Thanks a lot for figuring this out!
But... I do not like the fix. It does depend on memory layout on very subtle way.
What about switching to temporary, PSE-enabled pagetables in nosave area for suspend? Copying pagetables soon after boot should do the trick.
Pavel
-- 64 bytes from 195.113.31.123: icmp_seq=28 ttl=51 time=448769.1 ms
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |