On Wed, Feb 06, 2008 at 02:25:55PM -0500, Neil Horman wrote: > Hey all- > A hang on kdump was reported to me awhile back, only when systems died > via nmi watchdog panic. The hang wouldn't always be in the same place, but it > would usually be somewhere down in purgatory. In looking at the code, it > occured to me that since, during an nmi interrupt, we won't be able to handle > additional interrupts, that we won't be able to halt the other processors on a > system like we try to do in machine_crash_shutdown. As such, it appears that > leaving the other cpus running exposes us to the risk that another processor > will encounter an error and halt the system while we are trying to boot the > kdump kernel, and that can result in a hang. I wrote the attached patch to end > the nmi interrupt prior to calling crash_kexec from within die_nmi, and testing > here has proven successfull. > Hi Neil, Why wouldn't I be able to stop other cpus if I am inside an NMI handler? I just need to send an NMI IPI to other cpus and they should be able to receive and handle it? Thanks Vivek
