On 5/30/07, Akemi Yagi <amyagi at gmail.com> wrote: > On 5/30/07, Feizhou <feizhou at graffiti.net> wrote: > > Dan Halbert wrote: > > > Feizhou wrote: > > > I searched for the commit id in the Redhat bugzilla, and found it for > > > RHEL5: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=238709. That > > > bug says the fix has been backported and is in RHEL5 kernel > > > 2.6.18-18.el5. But I don't see anything about backporting to RHEL4. > > > > I see. So forget RAM >= 4GB on Centos 4 on AMD AM2. Hmmph. > > Well, not really. There seems to be a test kernel (2.6.9-42.EL) with > this bug fix at: > > http://people.redhat.com/coldwell/kernel/bugs/223238/ > > Therefore, upstream may be working on backporting for RHEL4 > (hopefully). Note also that the official patched version for CentOS 5 > will not be available for a while either. The 2.6.18-18.el5 kernel > might be for RHEL 5.1. > > Because the patch is available now, another option is to rebuild the > kernel by applying it. Certainly not for everyone but if the fix is > needed right now, this is the olny option. > > Akemi The patch file for this bug did not work on the CentOS source file as such. I have recreated it for CentOS 5.0 x86_64 (see below) and was able to rebuild kernels. It you ever decided to do the same, here's the modified patch, pci-gart.c : --- 2.6-git.orig/arch/x86_64/kernel/pci-gart.c +++ 2.6-git/arch/x86_64/kernel/pci-gart.c @@ -523,6 +523,10 @@ gatt = (void *)__get_free_pages(GFP_KERNEL, get_order(gatt_size)); if (!gatt) panic("Cannot allocate GATT table"); + if (change_page_attr_addr((unsigned long)gatt, gatt_size >> PAGE_SHIFT, PAGE_KERNEL_NOCACHE)) + panic("Could not set GART PTEs to uncacheable pages"); + global_flush_tlb(); + memset(gatt, 0, gatt_size); agp_gatt_table = gatt; ================================ Then edit the kernel-2.6.spec file as follows: Add this at line ~935 or so Patch40000: pci_new.patch Add this at line ~1908 or so %patch40000 -p1 Good luck, Akemi