* Ingo Molnar <mingo@kernel.org> wrote:

> 
> * Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:
> 
> > Hello, Ingo,
> > 
> > The changes in this series include:
> > 
> > 1.	Update RCU documentation.  These were posted to LKML at
> > 	https://lkml.org/lkml/2014/7/7/650.
> > 
> > 2.	Miscellaneous fixes.  These were posted to LKML at
> > 	https://lkml.org/lkml/2014/7/7/678.
> > 
> > 3.	Maintainership changes.  These were posted to LKML at
> > 	https://lkml.org/lkml/2014/7/7/713, with a couple of
> > 	additional at https://lkml.org/lkml/2014/7/3/812 and
> > 	https://lkml.org/lkml/2014/6/2/585.
> > 
> > 4.	Torture-test updates.  These were posted to LKML at
> > 	https://lkml.org/lkml/2014/7/7/816.
> > 
> > 5.	Callback-offloading changes.  These were posted to LKML at
> > 	https://lkml.org/lkml/2014/7/7/1007.
> > 
> > All of these have been exposed to -next testing.

JFYI, the attached x86 (rand!-) config crashes on early bootup:

[    0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2
[    0.000000] ------------[ cut here ]------------
[    0.000000] WARNING: CPU: 0 PID: 0 at arch/x86/kernel/cpu/common.c:1439 warn_pre_alternatives+0x1e/0x20()
[    0.000000] You're using static_cpu_has before alternatives have run!
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.16.0-rc5+ #236363
[    0.000000] Hardware name: System manufacturer System Product Name/A8N-E, BIOS ASUS A8N-E ACPI BIOS Revision 1008 08/22/2005
[    0.000000]  0000000000000000 ffffffff82787c60 ffffffff81ff4ec0 ffffffff82787ca8
[    0.000000]  ffffffff82787c98 ffffffff810651ac ffffffff81011531 ffffffff82787e48
[    0.000000]  0000000000000000 0000000000000000 ffffffff827cf880 ffffffff82787cf8
[    0.000000] Call Trace:
[    0.000000]  [<ffffffff81ff4ec0>] dump_stack+0x4d/0x66
[    0.000000]  [<ffffffff810651ac>] warn_slowpath_common+0x7a/0x93
[    0.000000]  [<ffffffff81011531>] ? warn_pre_alternatives+0x1e/0x20
[    0.000000]  [<ffffffff81065239>] warn_slowpath_fmt+0x4c/0x4e
[    0.000000]  [<ffffffff82005817>] ? irq_return+0x7/0x7
[    0.000000]  [<ffffffff81011531>] warn_pre_alternatives+0x1e/0x20
[    0.000000]  [<ffffffff81033d31>] __do_page_fault+0xc3/0x43f
[    0.000000]  [<ffffffff81005347>] ? print_context_stack+0x6a/0xb6
[    0.000000]  [<ffffffff810045f1>] ? dump_trace+0x27d/0x294
[    0.000000]  [<ffffffff815b185b>] ? number.isra.1+0x127/0x22c
[    0.000000]  [<ffffffff8109abe2>] ? print_time.part.5+0x58/0x5c
[    0.000000]  [<ffffffff81086a9a>] ? sched_clock_cpu+0x11/0xb9
[    0.000000]  [<ffffffff810340ef>] do_page_fault+0x1e/0x54
[    0.000000]  [<ffffffff82005817>] ? irq_return+0x7/0x7
[    0.000000]  [<ffffffff82006872>] page_fault+0x22/0x30
[    0.000000]  [<ffffffff815b65fa>] ? __bitmap_or+0x15/0x28
[    0.000000]  [<ffffffff82c876f0>] rcu_init_one+0x4c0/0x55d
[    0.000000]  [<ffffffff82c87b00>] rcu_init+0x270/0x2da
[    0.000000]  [<ffffffff82c6ec82>] start_kernel+0x24f/0x4d2
[    0.000000]  [<ffffffff82c6e841>] ? set_init_arg+0x53/0x53
[    0.000000]  [<ffffffff82c6e453>] x86_64_start_reservations+0x2a/0x2c
[    0.000000]  [<ffffffff82c6e546>] x86_64_start_kernel+0xf1/0xf4
[    0.000000] ---[ end trace 4650963e41188009 ]---
[    0.000000] BUG: unable to handle kernel NULL pointer dereference at           (null)
[    0.000000] IP: [<ffffffff815b65fa>] __bitmap_or+0x15/0x28
[    0.000000] PGD 0 
[    0.000000] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W     3.16.0-rc5+ #236363
[    0.000000] Hardware name: System manufacturer System Product Name/A8N-E, BIOS ASUS A8N-E ACPI BIOS Revision 1008 08/22/2005
[    0.000000] task: ffffffff827a3480 ti: ffffffff82784000 task.ti: ffffffff82784000
[    0.000000] RIP: 0010:[<ffffffff815b65fa>]  [<ffffffff815b65fa>] __bitmap_or+0x15/0x28
[    0.000000] RSP: 0000:ffffffff82787ef8  EFLAGS: 00010002
[    0.000000] RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000000000001
[    0.000000] RDX: 0000000000000000 RSI: ffff880000019800 RDI: ffff880000019800
[    0.000000] RBP: ffffffff82787ef8 R08: 0000000000000000 R09: 0000000000000000
[    0.000000] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff827cf880
[    0.000000] R13: 0000000000000002 R14: ffffffff827cf880 R15: 00000000001cd000
[    0.000000] FS:  0000000000000000(0000) GS:ffff88003f800000(0000) knlGS:0000000000000000
[    0.000000] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    0.000000] CR2: 0000000000000000 CR3: 000000000279e000 CR4: 00000000000006b0
[    0.000000] Stack:
[    0.000000]  ffffffff82787f50 ffffffff82c876f0 ffffffff83b7e7a0 0000000000000001
[    0.000000]  0000000000000082 0000000200000000 00000000ffffffff ffffffff82d37920
[    0.000000]  ffff88003ffbba40 ffffffff82d3e890 0000000000000000 ffffffff82787f80
[    0.000000] Call Trace:
[    0.000000]  [<ffffffff82c876f0>] rcu_init_one+0x4c0/0x55d
[    0.000000]  [<ffffffff82c87b00>] rcu_init+0x270/0x2da
[    0.000000]  [<ffffffff82c6ec82>] start_kernel+0x24f/0x4d2
[    0.000000]  [<ffffffff82c6e841>] ? set_init_arg+0x53/0x53
[    0.000000]  [<ffffffff82c6e453>] x86_64_start_reservations+0x2a/0x2c
[    0.000000]  [<ffffffff82c6e546>] x86_64_start_kernel+0xf1/0xf4
[    0.000000] Code: 4c 89 04 c7 4d 09 c1 48 ff c0 eb e8 31 c0 4d 85 c9 0f 95 c0 5d c3 55 48 63 c9 31 c0 48 83 c1 3f 48 89 e5 48 c1 e9 06 39 c1 7e 11 <4c> 8b 04 c2 4c 0b 04 c6 4c 89 04 c7 48 ff c0 eb eb 5d c3 55 48 
[    0.000000] RIP  [<ffffffff815b65fa>] __bitmap_or+0x15/0x28
[    0.000000]  RSP <ffffffff82787ef8>
[    0.000000] CR2: 0000000000000000
[    0.000000] ---[ end trace 4650963e4118800a ]---
[    0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
[    0.000000] Rebooting in 1 seconds..Press any key to enter the menu

Excluding the new RCU bits from tip:master makes it boot.

Any idea what's wrong?

Thanks,

	Ingo