This patch dies on boot for me, using sn2_defconfig. It is dies on the kernel/cpu.c line:
mutex_lock(&cpu_hotplug.lock); This is in cpu_hotplug_begin(), called from _cpu_up(), called from cpu_up(). I haven't finished verifying this yet, but it looks like the initialization of the mutex cpu_hotplug.lock in cpu_hotplug_init() only happens if CONFIG_HOTPLUG_CPU is enabled, but the use of that mutex in the above mutex_lock() call happens on all configs. In the sn2_defconfig I'm using, as well as in several other ia64, mips and powerpc configs, CONFIG_HOTPLUG_CPU is, at present anyway, disabled. For the record, the kernel death messages are: === Unable to handle kernel NULL pointer dereference (address 0000000000000000) swapper[1]: Oops 8804682956800 [1] Modules linked in: Pid: 1, CPU 0, comm: swapper psr : 00001010085a2010 ifs : 800000000000038b ip : [<a00000010081e080>] Not tainted ip is at __mutex_lock_slowpath+0x280/0x660 unat: 0000000000000000 pfs : 000000000000038b rsc : 0000000000000003 rnat: 1fcc5c7d8b12a4b4 bsps: 000000000001003e pr : 0000000000001041 ldrs: 0000000000000000 ccv : 0000000000000000 fpsr: 0009804c8a70433f csd : 0000000000000000 ssd : 0000000000000000 b0 : a00000010081e040 b6 : e0000030025bee60 b7 : a0000001005315c0 f6 : 1003e1111111111111111 f7 : 1003e20c49ba5e353f7cf f8 : 1003e00000000000000c8 f9 : 10006c7fffffffd73ea5c f10 : 100019ffffffff8a77fd5 f11 : 1003e0000000000000000 r1 : a000000101064760 r2 : a00000010118ef80 r3 : e00000b020377b20 r8 : e00000b020377d00 r9 : 0000000000004000 r10 : e00000b020370b58 r11 : e00000b020370000 r12 : e00000b020377cf0 r13 : e00000b020370000 r14 : 0000000000000001 r15 : e00000b020377d18 r16 : e00000b020377768 r17 : 00000000dead4ead r18 : a000000100d01380 r19 : a000000100e68300 r20 : 0000000000004000 r21 : 0000000000000010 r22 : 0000000000000000 r23 : 0000000000000000 r24 : 0000000000004000 r25 : ffffffffffffffff r26 : e00000b020377d10 r27 : 0000000000000000 r28 : e00000b020377d00 r29 : e00000b020377d08 r30 : a00000010118efa0 r31 : a00000010118ef98 Call Trace: [<a000000100013a60>] show_stack+0x40/0xa0 sp=e00000b0203778c0 bsp=e00000b020370f80 [<a000000100014360>] show_regs+0x840/0x880 sp=e00000b020377a90 bsp=e00000b020370f28 [<a000000100036460>] die+0x220/0x300 sp=e00000b020377a90 bsp=e00000b020370ee0 [<a000000100059cd0>] ia64_do_page_fault+0x910/0xa80 sp=e00000b020377a90 bsp=e00000b020370e90 [<a00000010000b120>] ia64_leave_kernel+0x0/0x280 sp=e00000b020377b20 bsp=e00000b020370e90 [<a00000010081e080>] __mutex_lock_slowpath+0x280/0x660 sp=e00000b020377cf0 bsp=e00000b020370e38 [<a00000010081e4a0>] mutex_lock+0x40/0x60 sp=e00000b020377d20 bsp=e00000b020370e18 [<a000000100a2c7e0>] cpu_up+0x220/0x6a0 sp=e00000b020377d20 bsp=e00000b020370dd0 [<a000000100a044d0>] kernel_init+0x250/0x7e0 sp=e00000b020377d30 bsp=e00000b020370d88 [<a000000100011fd0>] kernel_thread_helper+0xd0/0x100 sp=e00000b020377e30 bsp=e00000b020370d60 [<a000000100008dc0>] start_kernel_thread+0x20/0x40 sp=e00000b020377e30 bsp=e00000b020370d60 Kernel panic - not syncing: Attempted to kill init! -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson <[EMAIL PROTECTED]> 1.925.600.0401 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/