On Tue, Jul 10, 2012 at 10:58:35AM +0800, [email protected] wrote:
> Hi Jason,
>
> This HEAD commit in kgdb-next makes kgdb boot time tests freeze.
> The kernel is tested inside kvm with the attached config.
>
> 3751d3e85cf693e10e2c47c03c8caa65e171099b is the first bad commit
> commit 3751d3e85cf693e10e2c47c03c8caa65e171099b
> Author: Jason Wessel <[email protected]>
> Date: Fri Mar 23 09:35:05 2012 -0500
>
> x86,kgdb: Fix DEBUG_RODATA limitation using text_poke()
Jason, now that commit is merged into Linus' tree and showing up in
various other development trees that base on v3.6-rc1.
kernel boots reliably freeze on:
[ 4.527958] Write protecting the kernel read-only data: 10240k
[ 4.529326] debug: unmapping init memory ffff880001522000..ffff880001600000
[ 4.530566] debug: unmapping init memory ffff880001829000..ffff880001a00000
[ 4.549375] KGDB: BP remove failed: ffffffff81035be9
The freeze will disappear if removing CONFIG_KGDB*. It will change
into this oops if reverting the commit (either doing it on v3.6-rc1,
or by checking out 3751d3e85c~1):
[ 3.027423] kgdbts: ERROR PUT: end of test buffer on 'do_fork_test' line 2 expected T0* got $W01#b8
[ 3.029281] ------------[ cut here ]------------
[ 3.030154] WARNING: at /c/wfg/linux/drivers/misc/kgdbts.c:813 run_simple_test+0x24f/0x277()
[ 3.031624] Pid: 117, comm: reboot Not tainted 3.6.0-rc1-bisect-00198-gb1b7253 #47
[ 3.033271] Call Trace:
[ 3.033694] [<ffffffff813f1a11>] ? run_simple_test+0x24f/0x277
[ 3.034881] [<ffffffff810353f6>] warn_slowpath_common+0x5d/0x74
[ 3.036026] [<ffffffff810354bb>] warn_slowpath_null+0x15/0x1a
[ 3.037285] [<ffffffff813f1a11>] run_simple_test+0x24f/0x277
[ 3.038436] [<ffffffff813f142c>] kgdbts_put_char+0x18/0x1a
[ 3.039463] [<ffffffff81085f88>] gdbstub_exit+0xc6/0xe2
[ 3.040568] [<ffffffff81084cef>] dbg_notify_reboot+0x2a/0x2e
[ 3.041632] [<ffffffff81052568>] notifier_call_chain+0x32/0x5c
[ 3.042760] [<ffffffff810527ff>] __blocking_notifier_call_chain+0x47/0x60
[ 3.044054] [<ffffffff81052827>] blocking_notifier_call_chain+0xf/0x11
[ 3.045390] [<ffffffff810449ae>] kernel_restart_prepare+0x18/0x38
[ 3.046511] [<ffffffff81044a07>] kernel_restart+0xf/0x4b
[ 3.047540] [<ffffffff81044c2f>] sys_reboot+0x129/0x15e
[ 3.048732] [<ffffffff81072f0f>] ? trace_hardirqs_off+0xd/0xf
[ 3.049784] [<ffffffff8105c556>] ? local_clock+0x65/0x8b
[ 3.050786] [<ffffffff8106f8b2>] ? lock_release_holdtime+0x9e/0xa3
[ 3.051964] [<ffffffff81344974>] ? do_raw_spin_unlock+0xa7/0xb0
[ 3.053177] [<ffffffff8155fda5>] ? sysret_check+0x22/0x5d
[ 3.054124] [<ffffffff81072dfc>] ? trace_hardirqs_on_caller+0x125/0x181
[ 3.055388] [<ffffffff81332e8e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 3.056667] [<ffffffff8155fd79>] system_call_fastpath+0x16/0x1b
Attached is the full dmesg for the above oops and config.
Thanks,
Fengguang