The latest house cleaning of the Linux kernel is looking to drop support for IBM Cell Blade servers for those platforms from the better part of two decades ago with Cell BE processors that also had worked their way into some supercomputers at the time.
The Cell Broadband Engine Architecture was interesting back in the day for powering the PlayStation 3 and then going on to be found within various Cell Blade servers including the likes of the Roadrunner supercomputer. But there are no major users of Cell Blades left that are running upstream Linux kernels and even the Linux kernel developers involved are no longer hanging onto the hardware or beginning to run into the hardware failing. Thus with the upstream kernel developers/maintainers losing the ability to test new patches/kernel on the hardware, it looks like support for the Cell Blades will be retired.
Michael Ellerman sent out the set of 25 patches that would remove support for IBM Cell Blades from the mainline kernel. Ellerman commented:
“IBM Cell Blades used the Cell processor and the “blade” server form factor. They were sold as models QS20, QS21 & QS22 from roughly 2006 to 2012. They were used in a few supercomputers (eg. Roadrunner) that have since been dismantled, and were not that widely used otherwise.
Until recently I still had a working QS22, which meant I was able to keep the platform support working, but unfortunately that machine has now died.
I’m not aware of any users. If there is a user that wants to keep the upstream support working, we can look at bringing some of the code back as appropriate.
…
Remove the top-level config symbol PPC_IBM_CELL_BLADE, and then the dependent symbols PPC_CELL_NATIVE, PPC_CELL_COMMON, CBE_RAS, PPC_IBM_CELL_RESETBUTTON, PPC_IBM_CELL_POWERBUTTON, CBE_THERM, and AXON_MSI. Then remove the associated C files and headers, and trim unused header content (some is shared with PS3).Note that PPC_CELL_COMMON sounds like it would build code shared with PS3, but it does not. It’s a relic from when code was shared between the Blade support and QPACE support.”
So with this patch series the support for IBM Cell Blade servers would be removed. Clearing out that old platform support is some 6k lines lightening of the kernel.
