Zou, Nanhai wrote: >>> But this will rely on machine crash on CPU 0? >> We do not rely on machine crash on CPU 0 any more. If the >> crashing CPU is not cpu 0 and the cpu 0 not being returned to >> the slave loop, this case is handled by our PROM now. >> >> However, if somebody tries to boot up a production kernel using '-le' >> option _after_ the kexec'ed kernel is up running, the third kernel >> would not boot unless we boot up the second kernel with cpu 0. I >> posted a question on "if running 'kexec -le' on a kexec'ed kdump >> kernel is legal" earlier and Vivek responded saying the scenario >> is not guranteed to work. So, i think we are fine here. > > Ok, so with this patch and the PROM fix, on a SN system, > 1. Kdump -> 2nd kernel works. > 2. Kdump -> 2nd kernel -> Kexec to third kernel will not work. > 3. Kexec -> 2nd Kernel -> Kexec -> 3rd kernel works? > 4. Kexec -> 2nd Kernel -> Kdump -> 3rd kernel works? > > I think if scenario 1, 3 and 4 works it will be ok. Scenario 2 is not so useful I guess. Hi Nanhai, Where do we stand as to this patch's concern? Did you include this yet? As to Scenario 3 and 4, 'kexec -l' failed on "Inivalid memory segment" on SN Altix systems, and i have not had time to dig into it. This patch is pretty much doing what you suggested "calling ia64_jump_to_sal" to send the cpus to slave loop. We can include cpu 0 also by calling fix_b0_for)bsp() to set up b0 for cpu 0 in ia64_mca_init(), if so desired. What do you think? Regards, - jay [root@pogo1 boot]# /home/jlan/kexec-noio -l /boot/vmlinuz-2.6.18-kdump --noio - -initrd=/boot/initrd-2.6.18-kdump --append="root=/dev/sdb6 irqpoll ro console=t tySG0" Done with process_options kernel: 0x2000000000328010 kernel_size: 3502601 memory_range: crashk, idx=5, start=3018000000, end=3028000000 memory_range: Boot, idx=7, start=307a280010, end=307a280061 memory_range: MemoryMap, idx=9, start=307a3f0010, end=307a3f0611 build_mem_shdrs: ei_class=2, e_shnum=46, e_shoff=54506776 build_mem_shdrs: sizeof(e_shdr)=72, e_shdr=0x6000000000014120 ready to load. type=0, build_mem_shdrs: ei_class=2, e_shnum=46, e_shoff=54506776 build_mem_shdrs: sizeof(e_shdr)=72, e_shdr=0x6000000000014f30 elf_exec_load Invalid memory segment 0x4000000 - 0x4997fff Segmentation fault [root@pogo1 boot]# > - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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