Aditya Gupta
Linux Developer, Linux Technology Center (LTC), IBM
Delhi, India
Actions
I am a Developer at IBM, working with the Linux Technology Center team.
My job and my interests lie in the system bringup area (including the emulation, firmware and the kernel) and any random technical thing which interests me.
Have given a small talk earlier at a Kernel Meetup, on a similar topic about enabling GDB stack unwinding in crash-tool.
Area of Expertise
Emulating Firmware-Assisted Crash Dumps with QEMU
Firmware Assisted Dump (aka Fadump) is a reliable alternative dump mechanism to kdump.
In case of a crash, fadump does a memory preserving boot, and all devices are reset, as in a fresh reboot, unlike kdump where the devices can remain in bad state.
Then the second kernel/crashkernel is booted with hints from the firmware (in device tree, in case of PowerPC) to tell it's a fadump boot.
It's more reliable, as it resets all devices, and depends on the firmware to boot the next kernel, unlike on the just-crashed kernel in case of kdump.
The talk is focused on emulating the hardware/firmware side of fadump, in case of both PowerVM and PowerNV (Virtualised and Bare-metal).
The only basic hardware/firmware support needed to have fadump in an architecture, is to have an option for "Memory Preserving Boot", which QEMU does have.
The implementation replicates the hardware (and firmware's also in case of PowerVM) responsibilities in QEMU, including preserving memory regions requested by the first kernel CPU registers, HPTE, and custom memory regions like kernel commandline.
This talk will benefit architectures looking for a more reliable alternative to kdump.
Please note that Sessionize is not responsible for the accuracy or validity of the data provided by speakers. If you suspect this profile to be fake or spam, please let us know.
Jump to top