Red Hat Bugzilla – Bug 139465
em64t/ia32e kernel panic: 'interrupt handler - not syncing' during heavy network I/O
Last modified: 2007-11-30 17:07:05 EST
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040510 Description of problem: I have a dual processor EM64T/ia32e based system. Only one processor is installed and hyperthreading is off. The system also has an Adaptec ANA620xx/ANA69011A four-port NIC that uses the starfire driver. I'm using a floodping test to generate heavy I/O between the loopbacked ports of the starfire card. During this test the system will lock up hard with a kernel panic in less than 5 minutes. Kernel panic: map_single : could not allocate software IO TLB (106 bytes) In interrupt handler - not syncing A reboot of the system is necessary. So far I've only been able to generate this error 3 of 8 tries. Perhaps this is a timing problem? This happens in either SMP or UP mode using the x86_64 kernel (2.4.21-20.EL). It seems the starfire card can do 64-bit DMA. Version-Release number of selected component (if applicable): RedHat Enterprise Linux 3 Workstaion (Update 3) How reproducible: Sometimes Steps to Reproduce: 1.install 4-port NIC 2.initialise each interface 3.generate heavy network load Actual Results: Kernel panic: map_single : could not allocate software IO TLB (106 bytes) In interrupt handler - not syncing Expected Results: Packets should continue to be transmitted/received, the kernel should not panic, and the machine should not lock up. Additional info: I can provide any dmesg or log files upon request.
No need for further info, you ran out of swoitlb entries. The default is 1024 pages or 4MB. If you add "swiotlb=2048" on the boot command line in /boot/grub/grub.conf you will double the number of the size of the iotlb to 8MB. I have tested that architecture up to 64MB or "swiotlb-16384". Let us know how that works out. Thanks, Larry Woodman
A fix for this problem has just been committed to the RHEL3 U5 patch pool this evening (in kernel version 2.4.21-27.5.EL).
passing the "swiotlb=2048" boot parameter fixed the problem for me. Thanks.
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-2005-294.html