From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.6) Gecko/20050302 Firefox/1.0.1 Fedora/1.0.1-1.3.2 Description of problem: CF8/CFC cycles may get intermingled creating a race condition. It is possible to have two CF8 writes before a CFC access, customer has seen a particular case when acpi_os_write_pci_configuration() is calling pci_conf1_write() which is protected by pci_config_lock, while a driver (tg3 in this case) is calling pci_conf1_write_config_dword() which is not protected. Version-Release number of selected component (if applicable): kernel-2.4.21-32 How reproducible: Sometimes Steps to Reproduce: 1. Load tg3 driver on EM64T. 2. 3. Actual Results: FSB trace showed several places where the system has CF8/CFC cycles which are getting intermingled. Expected Results: PCI access should be protected. Additional info: Attaching patch provided by the customer, they have verified that the patch fixes the problem.
Created attachment 116037 [details] Patch to synchronize access to PCI config space
Patch looks pretty sane to me, and fairly close to the x86 version. Not sure why they added NULL checks of *value for the pci_*_read_config_byte and pci_*_read_config_word but not to the pci_*_read_config_dword versions, but other than that, it looks fine...
Please add PM and QE acks to add this fix into U7. Thanks.
A fix for this problem has just been committed to the RHEL3 U7 patch pool this evening (in kernel version 2.4.21-37.6.EL).
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2006-0144.html