Assert INIT just after panic, before all other cpus have frozen Expected results: continue kdump invoked by panic, or restart kdump from INIT Actual results: might be hang, crashdump not retrieved Proposed Fix: This patch masks INIT first in panic path to take the initiative on kdump, and reuse atomic value kdump_in_progress to make sure there is only one initiator of kdump. All INITs asserted later should be used only for freezing all other cpus. This mask will be removed soon by rfi in relocate_kernel.S, before jump into kdump kernel, after all cpus are frozen and no-op INIT handler is registered. So if INIT was in the interval while it is masked, it will pend on the system and will received just after the rfi, and handled by the no-op handler. If there was a MCA event while psr.mc is 1, in theory the event will pend on the system and will received just after the rfi same as above. MCA handler is unregistered here at the time, so received MCA will not reach to OS_MCA and will result in warmboot by SAL. Note that codes in this masked interval are relatively simpler than that in MCA/INIT handler which also executed with the mask. So it can be said that probability of error in this interval is supposed not so higher than that in MCA/INIT handler. Signed-off-by: Hidetoshi Seto Cc: Vivek Goyal Cc: Haren Myneni Cc: kexec@lists.infradead.org Acked-by: Fenghua Yu Signed-off-by: Tony Luck õp “›¿