> -----Original Message----- > From: Jay Lan [mailto:jlan@xxxxxxx] > Sent: 2006年11月11日 3:23 > To: Zou, Nanhai > Cc: fastboot; Linux-IA64; Jack Steiner; Luck, Tony > Subject: Re: [PATCH]send slave cpus to SAL slave loop on crash (IA64) > > 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? During kdump_cpu_freeze, putting everybody except cpu0 to rendez state looks like a hack... However fix_b0_for_bsp is another hack.... Since I think the first one looks less hacky, I will include your patch in my kdump patch. Thanks Zou Nan hai > > 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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