Jerome Glisse wrote: > On Sat, 2009-04-18 at 21:06 +0200, Thomas Hellström wrote: > >> Jerome Glisse wrote: >> >>> Hi Thomas >>> >>> I am getting massive error on x86_64, things like : >>> BUG: Bad page map in process gnome-session pte:1f1d1d1d01000000 >>> pmd:321a6067 >>> keep filling the log until very bad things happen. >>> Do you have any idea what might cause that in ttm ? >>> My assumption is that ttm vm code is guilty their. >>> Note that on x86 exact same code seem to run fine. >>> All this with 2.6.29 final. >>> >>> Cheers, >>> Jerome Glisse >>> >>> >>> >> Hi, Jerome! >> >> The TTM code may well be guilty here. I haven't tested x86-64 for a >> while, but I can probably give it a try on openChrome next week. >> >> /Thomas >> > > Okay so i really narrowed it down to asking for WC memory, so my guess > is that either my CPU (AMD Athlon(tm) Dual Core Processor 4450e) have > PAT issue either TTM PAT/WC code is wrong somehow. I haven't time yet > to go deeper with this but i think it worked on an Intel Core2 CPU > with x86-64. Also it seems other people doesn't have the issue with > WC on x86-64. > > PS: Sorry for all the noise, the bug didn't always showed up quickly so > i had false feeling. I am yet unsure it's fully fixed but so far all my > test case which triggered it seems to work fine. > > Cheers, > Jerome > >
Jerome, I think I missed what the fix was? Anyway, for PAT-aware kernels the drm git TTM code is always assuming PAT is enabled and working. For production kernels, the function pgprot_ttm_x86_wc should be replaced by an exported version of x86 pgprot_writecombine. FWIW x86-64 seems to work fine here on a 2.6.27 kernel Athlon-64 single-core on openChrome. /Thomas ------------------------------------------------------------------------------ Stay on top of everything new and different, both inside and around Java (TM) technology - register by April 22, and save $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. 300 plus technical and hands-on sessions. Register today. Use priority code J9JMT32. http://p.sf.net/sfu/p -- _______________________________________________ Dri-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dri-devel
